The leucine-rich repeat(LRR)protein family is involved in a variety of fundamental metabolic and signaling processes in plants,including growth and defense responses.LRR proteins can be divided into two categories:tho...The leucine-rich repeat(LRR)protein family is involved in a variety of fundamental metabolic and signaling processes in plants,including growth and defense responses.LRR proteins can be divided into two categories:those containing LRR domains along with other structural elements,which are further subdivided into five groups,LRR receptor-like kinases,LRR receptor-like proteins,nucleotide-binding site LRR proteins,LRR-extensin proteins,and polygalacturonase-inhibiting proteins,and those containing only LRR domains.Functionally,various LRR proteins are primarily involved in plant development and responses to environmental stress.Notably,the LRR protein family plays a central role in signal transduction pathways related to stress adaptation.In this review,we classify and analyze the functions of LRR proteins in plants.While extensive research has been conducted on the roles of LRR proteins in disease resistance signaling,these proteins also play important roles in abiotic stress responses.This review highlights recent advances in understanding how LRR proteins mediate responses to biotic and abiotic stresses.Building upon these insights,further exploration of the roles of LRR proteins in abiotic stress resistance may aid efforts to develop rice varieties with enhanced stress and disease tolerance.展开更多
The nucleotide-binding domain,leucine-rich repeat,and pyrin domain-containing protein 3(NLRP3)inflammasome is a critical modulator in inflammatory disease.Activation and mutation of NLRP3 can cause severe inflammation...The nucleotide-binding domain,leucine-rich repeat,and pyrin domain-containing protein 3(NLRP3)inflammasome is a critical modulator in inflammatory disease.Activation and mutation of NLRP3 can cause severe inflammation in diseases such as chronic infantile neurologic cutaneous and articular syndrome,Muckle-Wells syndrome,and familial cold autoinflammatory syndrome 1.To date,a great effort has been made to decode the underlying mechanisms of NLRP3 activation.The priming and activation of NLRP3 drive the maturation and release of active interleukin(IL)-18 and IL-1βto cause inflammation and pyroptosis,which can significantly trigger many diseases including inflammatory diseases,immune disorders,metabolic diseases,and neurodegenerative diseases.The investigation of NLRP3 as a therapeutic target for disease treatment is a hot topic in both preclinical studies and clinical trials.Developing potent NLRP3 inhibitors and downstream IL-1 inhibitors attracts wide-spectrum attention in both research and pharmaceutical fields.In this minireview,we first updated the molecular mechanisms involved in NLRP3 inflammasome activation and the associated downstream signaling pathways.We then reviewed the molecular and cellular pathways of NLRP3 in many diseases,including obesity,diabetes,and other metabolic diseases.In addition,we briefly reviewed the roles of NLRP3 in cancer growth and relative immune checkpoint therapy.Finally,clinical trials with treatments targeting NLRP3 and its downstream signaling pathways were summarized.展开更多
BACKGROUND Colon cancer cell lines are widely used for research and for the screening of drugs that specifically target the stem cell compartment of colon cancers.It was reported that colon cancer carcinoma specimens ...BACKGROUND Colon cancer cell lines are widely used for research and for the screening of drugs that specifically target the stem cell compartment of colon cancers.It was reported that colon cancer carcinoma specimens contain a subset of leucine-rich repeatcontaining G protein-coupled receptor 5(LGR5)-expressing stem cells,these socalled“tumour-initiating”cells,reminiscent in their properties of the normal intestinal stem cells(ISCs),may explain the apparent heterogeneity of colon cancer cell lines.Also,colon cancer is initiated by aberrant Wnt signaling in ISCs known to express high levels of LGR5.Furthermore,in vivo reports demonstrate the clonal expansion of intestinal adenomas from a single LGR5-expressing cell.AIM To investigate whether colon cancer cell lines contain cancer stem cells and to characterize these putative cancer stem cells.METHODS A portable fluorescent reporter construct based on a conserved fragment of the LGR5 promoter was used to isolate the cell compartments expressing different levels of LGR5 in two widely used colon cancer cell lines(Caco-2 and LoVo).These cells were then characterized according to their proliferation capacity,gene expression signatures of ISC markers,and their tumorigenic properties in vivo and in vitro.RESULTS The data revealed that the LGR5 reporter can be used to identify and isolate a classical intestinal crypt stem cell-like population from the Caco-2,but not from the LoVo,cell lines,in which the cancer stem cell population is more akin to B lymphoma Moloney murine leukemia virus insertion region 1 homolog(+4 crypt)stem cells.This sub-population within Caco-2 cells exhibits an intestinal cancer stem cell gene expression signature and can both self-renew and generate differentiated LGR5 negative progeny.Our data also show that cells expressing high levels of LGR5/enhanced yellow fluorescent protein(EYFP)from this cell line exhibit tumorigenic-like properties in vivo and in vitro.In contrast,cell compartments of LoVo that are expressing high levels of LGR5/EYFP did not show these stem cell-like properties.Thus,cells that exhibit high levels of LGR5/EYFP expression represent the cancer stem cell compartment of Caco-2 colon cancer cells,but not LoVo cells.CONCLUSION Our findings highlight the presence of a spectrum of different ISC-like compartments in different colon cancer cell lines.Their existence is an important consideration for their screening applications and should be taken into account when interpreting drug screening data.We have generated a portable LGR5-reporter that serves as a valuable tool for the identification and isolation of different colon cancer stem cell populations in colon cancer lines.展开更多
BACKGROUND Cancer stem cells(CSCs)are a subpopulation of cancer cells with the potential of self-renewal and differentiation.CSCs play critical roles in tumorigenesis,recurrence,metastasis,radiation tolerance and chem...BACKGROUND Cancer stem cells(CSCs)are a subpopulation of cancer cells with the potential of self-renewal and differentiation.CSCs play critical roles in tumorigenesis,recurrence,metastasis,radiation tolerance and chemoresistance.AIM To assess the expression patterns and clinical potential of doublecortin-like kinase 1(DCLK1)and leucine-rich repeat-containing G-protein-coupled receptor 5(Lgr5),as prognostic CSC markers of colorectal cancer(CRC).METHODS The expression of DCLK1 and Lgr5 in CRC tissue sections from 92 patients was determined by immunohistochemistry.Each case was evaluated using a combined scoring method based on signal intensity staining(scored 0-3)and the proportion of positively stained cancer cells(scored 0-3).The final staining score was calculated as the intensity score multiplied by the proportion score.Low expression of DCLK1 and Lgr5 was defined as a score of 0-3;high expression of DCLK1 and Lgr5 was defined as a score of≥4.Specimens were categorized as either high or low expression,and the correlation between the expression of DCLK1 or Lgr5 and clinicopathological factors was investigated.RESULTS DCLK1 and Lgr5 expression levels were significantly positively correlated.CRC patients with high DCLK1,Lgr5 and DCLK1/Lgr5 expressions had poorer progression-free survival and overall survival.Moreover,high expression of DCLK1 was an independent prognostic factor for recurrence and overall survival in patients with CRC by multivariate analysis(P=0.026 and P=0.049,respectively).CONCLUSION DCLK1 may be a potential CSC marker for the recurrence and survival of CRC patients.展开更多
Aim： To investigate the role of CAG and GGN repeats as genetic background affecting androgen insensitivity syndrome （AIS） phenotype. Methods： We analyzed lengths of androgen receptor （AR）-CAG and GGN repeats in ...Aim： To investigate the role of CAG and GGN repeats as genetic background affecting androgen insensitivity syndrome （AIS） phenotype. Methods： We analyzed lengths of androgen receptor （AR）-CAG and GGN repeats in 69 AIS cases, along with 136 unrelated normal male individuals. The lengths of repeats were analyzed using polymerase chain reaction （PCR） amplification followed by allelic genotyping to determine allele length. Results： Our study revealed significantly shorter mean lengths of CAG repeats in patients （mean 18.25 repeats, range 14-26 repeats） in comparison to the controls （mean 22.57 repeats, range 12-39 repeats） （two-tailed P 〈 0.0001）. GGN repeats, however, did not differ significantly between patients （mean 21.48 repeats） and controls （mean 21.21 repeats） （two- tailed P = 0.474）. Among patients＇ groups, the mean number of CAG repeats in partial androgen insensitivity cases （mean 15.83 repeats） was significantly less than in complete androgen insensitivity cases （mean 19.46 repeats） （two- tailed P 〈 0.0001）. Conclusion： The findings suggest that shorter lengths of repeats in the AR gene might act as low penetrance genetic background in varying manifestation of androgen insensitivity.展开更多
Axonal growth inhibitors are released during traumatic injuries to the adult mammalian central nervous system, including after spinal cord injury. These molecules accumulate at the injury site and form a highly inhibi...Axonal growth inhibitors are released during traumatic injuries to the adult mammalian central nervous system, including after spinal cord injury. These molecules accumulate at the injury site and form a highly inhibitory environment for axonal regeneration. Among these inhibitory molecules, myelinassociated inhibitors, including neurite outgrowth inhibitor A, oligodendrocyte myelin glycoprotein, myelin-associated glycoprotein, chondroitin sulfate proteoglycans and repulsive guidance molecule A are of particular importance. Due to their inhibitory nature, they represent exciting molecular targets to study axonal inhibition and regeneration after central injuries. These molecules are mainly produced by neurons, oligodendrocytes, and astrocytes within the scar and in its immediate vicinity. They exert their effects by binding to specific receptors, localized in the membranes of neurons. Receptors for these inhibitory cues include Nogo receptor 1, leucine-rich repeat, and Ig domain containing 1 and p75 neurotrophin receptor/tumor necrosis factor receptor superfamily member 19(that form a receptor complex that binds all myelin-associated inhibitors), and also paired immunoglobulin-like receptor B. Chondroitin sulfate proteoglycans and repulsive guidance molecule A bind to Nogo receptor 1, Nogo receptor 3, receptor protein tyrosine phosphatase σ and leucocyte common antigen related phosphatase, and neogenin, respectively. Once activated, these receptors initiate downstream signaling pathways, the most common amongst them being the Rho A/ROCK signaling pathway. These signaling cascades result in actin depolymerization, neurite outgrowth inhibition, and failure to regenerate after spinal cord injury. Currently, there are no approved pharmacological treatments to overcome spinal cord injuries other than physical rehabilitation and management of the array of symptoms brought on by spinal cord injuries. However, several novel therapies aiming to modulate these inhibitory proteins and/or their receptors are under investigation in ongoing clinical trials. Investigation has also been demonstrating that combinatorial therapies of growth inhibitors with other therapies, such as growth factors or stem-cell therapies, produce stronger results and their potential application in the clinics opens new venues in spinal cord injury treatment.展开更多
This study aimed to investigate the correlations among androgen receptor （AR） CAG repeat polymorphism, sex hormones and penile length in healthy Chinese young adult men. Two hundred and fifty-three healthy men （age...This study aimed to investigate the correlations among androgen receptor （AR） CAG repeat polymorphism, sex hormones and penile length in healthy Chinese young adult men. Two hundred and fifty-three healthy men （aged 22.8 ± 3.1years） were enrolled. The individuals were grouped as CAG short （CAGs） if they harbored repeat length of 〈20 or as CAG long （CAGL） if their CAG repeat length was 〉20. Body height/weight, penile length and other parameters were examined and recorded by the specified physicians; CAG repeat polymorphism was determined by the polymerase chain reaction （PCR） method; and the serum levels of the sex hormones were detected by radioimmunoassay. Student＇s t-test or linear regression analysis was used to assess the associations among AR CAG repeat polymorphism, sex hormones and penile length. This investigation showed that the serum total testosterone （T） level was positively associated with the AR CAG repeat length （P = 0.01）; whereas, no significant correlation of T or AR CAG repeat polymorphism with the penile length was found （P = 0.593）. Interestingly, an inverse association was observed between serum prolactin （PRL） levels and penile length by linear regression analyses （β = -0.024, P = 0.039, 95% confidence interval （CI）： -0.047, 0）. Collectively, this study provides the first evidence that serum PRL, but not T or AR CAG repeat polymorphism, is correlated with penile length in the Han adult population from northwestern China.展开更多
Leucine-rich repeat kinase 1 （LRRK1） plays a critical role in regulating cytoskeletal organization, osteoclast activity, and bone resorption with little effect on bone formation parameters. Deficiency of Lrrkl in mi...Leucine-rich repeat kinase 1 （LRRK1） plays a critical role in regulating cytoskeletal organization, osteoclast activity, and bone resorption with little effect on bone formation parameters. Deficiency of Lrrkl in mice causes a severe osteopetrosis in the metaphysis of the long bones and vertebrae bones, which makes LRRK1 an attractive alternative drug target for the treatment of osteoporosis and other high-turnover bone diseases. This review recent advances on the functions of the Lrrkl-related family members, Lrrkl deficiency-induced skeletal phenotypes, LRRK1 structure-function, potential biological substrates and interacting proteins, and the mechanisms of LRRK1 action in osteoclasts.展开更多
Leucine-rich repeats and immunoglobulin-like domains 1 （LRIG1） is an anti-oncogene. LRIG1 is correlated with Bcl-2 in ependymomas. Decreased Bcl-2 and manganese superoxide dismutase expression can improve the chemos...Leucine-rich repeats and immunoglobulin-like domains 1 （LRIG1） is an anti-oncogene. LRIG1 is correlated with Bcl-2 in ependymomas. Decreased Bcl-2 and manganese superoxide dismutase expression can improve the chemosensitivity of glioma. In the present study, a tissue microarray of human brain astrocytomas was constructed. To investigate the relationship of LRIG1 with Bcl-2 and manganese superoxide dismutase, LRIG1, Bcl-2 and manganese superoxide dismutase expression in our tissue microarray was determined using immunohistochemistry. In addition, we constructed the LRIG1-U251 cell line, and its responses to doxorubicin and temozolomide were detected using the MTT assay. Results showed that LRIG1 expression was significantly negatively correlated with Bcl-2 and manganese superoxide dismutase expression in glioma. Also, proliferation of LRIG1-U251 cells exposed to doxorubicin or temozolomide was significantly inhibited, i.e. in the LRIG1-U251 cell line, the chemosensitivity to doxorubicin and temozolomide was increased. This indicates that increased LRIG1 expression produces a chemosensitivity in glioma.展开更多
The current study investigated correlations between the expression of leucine-rich repeats and immunoglobulin-like domain 1 （LRIG1） and antioxidant enzymes and related proteins, including manganese superoxide dismut...The current study investigated correlations between the expression of leucine-rich repeats and immunoglobulin-like domain 1 （LRIG1） and antioxidant enzymes and related proteins, including manganese superoxide dismutase, glutamate cysteine ligase catalytic or regulatory subunit, thioredoxin and thioredoxin reductase, in both human ependymoma and oligodendroglioma. Results revealed that the cytoplasmic expression of LRIG1 was associated with expression of glutamate cysteine ligase catalytic subunit in the human ependymoma, while the nuclear expression of LRIG1 was associated with expression of thioredoxin reductase. In human oligodendroglioma, the cytoplasmic expression of LRIG1 was associated with expression of the glutamate cysteine ligase catalytic subunit. Both the nuclear and perinuclear expressions of LRIG1 were associated with expression of glutamate cysteine ligase regulatory subunit. These results indicated that several antioxidant enzymes and related proteins contributed to LRIG1 expression, and that these may participate in the antioxidation of the cells.展开更多
BACKGROUND F-box and leucine-rich repeat 6(FBXL6)have reportedly been associated with several cancer types.However,the role and mechanisms of FBXL6 in gastric cancer(GC)require further elucidation.AIM To investigate t...BACKGROUND F-box and leucine-rich repeat 6(FBXL6)have reportedly been associated with several cancer types.However,the role and mechanisms of FBXL6 in gastric cancer(GC)require further elucidation.AIM To investigate the effect of FBXL6 in GC tissues and cells and the underlying mechanisms.METHODS TCGA and GEO database analysis was performed to evaluate the expression of FBXL6 in GC tissues and adjacent normal tissues.Reverse transcription-quantitative polymerase chain reaction,immunofluorescence,and western blotting were used to detect the expression of FBXL6 in GC tissue and cell lines.Cell clone formation,5-ethynyl-2’-deoxyuridine(EdU)assays,CCK-8,transwell migration assay,and wound healing assays were performed to evaluate the malignant biological behavior in GC cell lines after transfection with FBXL6-shRNA and the overexpression of FBXL6 plasmids.Furthermore,in vivo tumor assays were performed to prove whether FBXL6 promoted cell proliferation in vivo.RESULTS FBXL6 expression was upregulated more in tumor tissues than in adjacent normal tissues and positively associated with clinicopathological characteristics.The outcomes of CCK-8,clone formation,and Edu assays demonstrated that FBXL6 knockdown inhibited cell proliferation,whereas upregulation of FBXL6 promoted proliferation in GC cells.Additionally,the transwell migration assay revealed that FBXL6 knockdown suppressed migration and invasion,whereas the overex pression of FBXL6 showed the opposite results.Through the subcutaneous tumor implantation assay,it was evident that the knockdown of FBXL6 inhibited GC graft tumor growth in vivo.Western blotting showed that the effects of FBXL6 on the expression of the proteins associated with the epithelial-mesenchymal transition-associated proteins in GC cells.CONCLUSION Silencing of FBXL6 inactivated the EMT pathway to suppress GC malignancy in vitro.FBXL6 can potentially be used for the diagnosis and targeted therapy of patients with GC.展开更多
Leucine rich repeats (LRRs) are present in over 14,000 proteins that have been identified in viruses, bacteria, archaea, and eukaryotes. Two to sixty-two LRRs occur in tandem forming an overall arc shaped domain. Ther...Leucine rich repeats (LRRs) are present in over 14,000 proteins that have been identified in viruses, bacteria, archaea, and eukaryotes. Two to sixty-two LRRs occur in tandem forming an overall arc shaped domain. There are eight classes of LRRs. Plant specific LRRs (class: PS-LRR) had previously been recognized in only plant proteins. However, we find that PS-LRRs are also present in proteins from bacteria. We investigated the origin of bacterial PS-LRR domains. PSLRR proteins are widely distributed in most plants;they are found in only a few bacterial species. There are no PS-LRR proteins from archaea. Bacterial PS-LRRs in twenty proteins from eleven bacterial species (in the three phyla: Proteobacteria, Cyanobacteria, and Bacteroidetes) are significantly more similar to the PS-LRR class than to the other seven classes of LRR proteins. Not only amino acid sequences but also nucleotide sequences of the bacterial PS-LRR domains show highly significant similarity with those of many plant proteins. The program, EGID (Ensemble algorithm for Genomic Island Detection), predicts that Synechococcus sp. CYA_ 1022 came from another organism. Four bacterial PS-LRR proteins contain AhpC-TSA, IgA peptidase M64, the immunoglobulin domain, the Calx-b domain, and the He_PIG domain;these domains show no similarity with any eukaryotic (plant) proteins, in contrast to the similarities of their respective PS-LRRs. The present results indicate that horizontal gene transfer (HGT) of genes/gene fragments encoding PS-LRR domains occurred between bacteria and plants, and HGT among the eleven bacterial species, of the three phyla, as opposed to descent from a common ancestor. There is the possibility of the occurrence of one HGT event from plant to bacteria. A series of HGTs might then have occurred recently and rapidly among these eleven species of bacteria.展开更多
AIM： To investigate the mechanism underlying the loss of responsiveness to anti-vascular endothelial growth factor（VEGF） treatment after repeated injections for choroidal neovascularization, VEGF and VEGF receptor...AIM： To investigate the mechanism underlying the loss of responsiveness to anti-vascular endothelial growth factor（VEGF） treatment after repeated injections for choroidal neovascularization, VEGF and VEGF receptor（VEGFR） expressions were evaluated following repeated bevacizumab treatments in hypoxic human umbilical vein endothelial cells（HUVECs） in vitro.METHODS： HUVECs were incubated under hypoxic conditions in two media of different bevacizumab concentrations（1.0 or 2.5 mg/m L） for 17 h, and then in a new medium without bevacizumab for 7h. This procedure was repeated twice more. A culture with an identical volume of excipients served as the control. Cytotoxicity and cell proliferation were assessed using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide and Ki-67 assays, respectively. Levels of VEGF and VEGFR were assessed using enzyme-linked immunosorbent assay and Western blot respectively.RESULTS： Cytotoxic effects were not reported for either bevacizumab concentration. Cell proliferation was not reduced after anti-VEGF treatments. VEGF level after single treatment was significantly higher than that of the control and after repeated treatments. Phosphorylated VEGFR-2 expression increased significantly after singleand repeated bevacizumab treatments compared with the control. The 1.0 mg/m L bevacizumab induced significantly higher expressions of VEGFR-2 than the 2.5 mg/m L in single and repeated treatment groups.CONCLUSION： Bevacizumab treatment of HUVECs elevated VEGFR expression in both single and repeated treatments, indicating a mechanism for the reduced efficacy of anti-VEGF therapy in ocular neovascular disorders.展开更多
We investigated the influence of the cytosine-adenine (CA) dinucleotide repeat polymorphism in intron 6 of estrogen receptor β (ERβ) gene on rheumatoid arthritis (RA) risk. One hundred and ninety-three RA patients a...We investigated the influence of the cytosine-adenine (CA) dinucleotide repeat polymorphism in intron 6 of estrogen receptor β (ERβ) gene on rheumatoid arthritis (RA) risk. One hundred and ninety-three RA patients and 77 control subjects with osteoarthritis (OA) were recruited. The CA repeat polymorphism was assayed by a dye-terminator cycle sequencing analysis. No statistically significant difference in the mean number of CA repeats between the RA and OA patients was observed (RA: 21.47, OA: 21.23, P = 0.324). The alleles were categorized according to the number of repeats: short (S, ≦21) and long (L, ≧22), in which the genotypes SS, SL, and LL were observed. No significant differences were observed for the allele and genotype distributions of this polymorphism in both patient groups. The RA patients were classified according to RA severity: mild (least erosive disease) and severe (more erosive and mutilating disease). Again, no significant difference in genotype frequency between these groups was observed, even after stratifying by sex. The present study indicates that additional studies are needed to clarify the roles of this polymorphism, estrogen, and ER in the development of autoimmune diseases.展开更多
Androgen receptor （AR） gene has been extensively studied in diverse clinical conditions. In addition to the point mutations, trinucleotide repeat （CAG and GGN） length polymorphisms have been an additional subject ...Androgen receptor （AR） gene has been extensively studied in diverse clinical conditions. In addition to the point mutations, trinucleotide repeat （CAG and GGN） length polymorphisms have been an additional subject of interest and controversy among geneticists. The polymorphic variations in triplet repeats have been associated with a number of disorders, but at the same time contradictory findings have also been reported. Further, studies on the same disorder in different populations have generated different results. Therefore, combined analysis or review of the published studies has been of much value to extract information on the significance of variations in the gene in various clinical conditions. AR genetics has been reviewed extensively but until now review articles have focused on individual clinical categories such as androgen insensitivity, male infertility, prostate cancer, and so on. We have made the first effort to review most the aspects of AR genetics. The impact of androgens in various disorders and polymorphic variations in the AR gene is the main focus of this review. Additionally, the correlations observed in various studies have been discussed in the light of in vitro evidences available for the effect of AR gene variations on the action of androgens.展开更多
The HIV-1 LTR controls the expression of HIV-1 viral genes and thus is critical for viral propagation and pathology. Numerous host factors have been shown to participate in the regulation of the LTR promoter. Among th...The HIV-1 LTR controls the expression of HIV-1 viral genes and thus is critical for viral propagation and pathology. Numerous host factors have been shown to participate in the regulation of the LTR promoter. Among them is the thyroid hormone (T3) receptor (TR). TR has been shown to bind to the critical region of the promoter that contain the NFbB and Sp1 binding sites. Interestingly, earlier transient transfection studies in tissue culture cells have yielded contradicting conclusions on the role of TR in LTR regulation, likely due to the use of different cell types and/or lack of proper chromatin organization. Here, using the frog oocyte as a model system that allows replication-coupled chromatin assembly, mimicking that in somatic cells, we demonstrate that unliganded heterodimers of TR and RXR (9-cis retinoic acid receptor) repress LTR while the addition of T3 relieves the repression and further activates the promoter. More importantly, we show that chromatin and unliganded TR/RXR synergize to repress the promoter in a histone deacetylase-dependent manner.展开更多
AIM:To characterize the regeneration-associated stem cell-related phenotype of hepatocyte-derived growth factor receptor(HGFR)-expressing cells in active ulcerative colitis(UC).METHODS:On the whole 38 peripheral blood...AIM:To characterize the regeneration-associated stem cell-related phenotype of hepatocyte-derived growth factor receptor(HGFR)-expressing cells in active ulcerative colitis(UC).METHODS:On the whole 38 peripheral blood samples and 38 colonic biopsy samples from 18 patients with histologically proven active UC and 20 healthy control subjects were collected.After preparing tissue microarrays and blood smears HGFR,caudal type homeobox 2(CDX2),prominin-1(CD133) and Musashi-1conventional and double fluorescent immunolabelings were performed.Immunostained samples were digitalized using high-resolution Mirax Desk instrument,and analyzed with the Mirax TMA Module software.For semiquantitative counting of immunopositive lamina propria(LP) cells 5 fields of view were counted at magnification x 200 in each sample core,then mean ± SD were determined.In case of peripheral blood smears,30 fields of view with 100 μm diameter were evaluated in every sample and the number of immunopositive cells(mean ± SD) was determined.Using 337 nm UVA Laser MicroDissection system at least 5000 subepithelial cells from the lamina propria were collected.Gene expression analysis of HGFR,CDX2,CD133,leucine-rich repeat-containing G-protein coupled receptor 5(Lgr5),Musashi-1 and cytokeratin20(CK20) were performed in both laser-microdisscted samples and blood samples by using real time reverse transcription polymerase chain reaction(RT-PCR).RESULTS:By performing conventional and double fluorescent immunolabelings confirmed by RT-PCR,higher number of HGFR(blood:6.7 ± 1.22 vs 38.5 ±3.18;LP:2.25 ± 0.85 vs 9.22 ± 0.65;P < 0.05),CDX2(blood:0 vs 0.94 ± 0.64;LP:0.75 ± 0.55 vs 2.11± 0.75;P < 0.05),CD133(blood:1.1 ± 0.72 vs 8.3± 1.08;LP:11.1 ± 0.85 vs 26.28 ± 1.71;P < 0.05)and Musashi-1(blood and LP:0 vs scattered) positive cells were detected in blood and lamina propria of UC samples as compared to controls.HGFR/CDX2(blood:0 vs 1± 0.59;LP:0.8 ± 0.69 vs 2.06 ± 0.72,P < 0.05)and Musashi-1/CDX2(blood and LP:0 vs scattered) coexpressions were found in blood and lamina propria of UC samples.HGFR/CD133 and CD133/CDX2 coexpressions appeared only in UC lamina propria samples.CDX2,Lgr5 and Musashi-1 expressions in UC blood samples were not accompanied by CK20 mRNA expression.CONCLUSION:In active UC,a portion of circulating HGFR-expressing cells are committed to the epithelial lineage,and may participate in mucosal regeneration by undergoing mesenchymal-to-epithelial transition.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.32072048 and U2004204)National Key Research and Development Program of China(Grant No.2023YFF1001200)+2 种基金China Rice Research Institute Basal Research Fund(Grant No.CPSIBRF-CNRRI-202404)Academician Workstation of National Nanfan Research Institute(Sanya),Chinese Agricultural Academic Science(CAAS),(Grant Nos.YBXM2422 and YBXM2423)Agricultural Science and Technology Innovation Program of CAAS,China.
文摘The leucine-rich repeat(LRR)protein family is involved in a variety of fundamental metabolic and signaling processes in plants,including growth and defense responses.LRR proteins can be divided into two categories:those containing LRR domains along with other structural elements,which are further subdivided into five groups,LRR receptor-like kinases,LRR receptor-like proteins,nucleotide-binding site LRR proteins,LRR-extensin proteins,and polygalacturonase-inhibiting proteins,and those containing only LRR domains.Functionally,various LRR proteins are primarily involved in plant development and responses to environmental stress.Notably,the LRR protein family plays a central role in signal transduction pathways related to stress adaptation.In this review,we classify and analyze the functions of LRR proteins in plants.While extensive research has been conducted on the roles of LRR proteins in disease resistance signaling,these proteins also play important roles in abiotic stress responses.This review highlights recent advances in understanding how LRR proteins mediate responses to biotic and abiotic stresses.Building upon these insights,further exploration of the roles of LRR proteins in abiotic stress resistance may aid efforts to develop rice varieties with enhanced stress and disease tolerance.
文摘The nucleotide-binding domain,leucine-rich repeat,and pyrin domain-containing protein 3(NLRP3)inflammasome is a critical modulator in inflammatory disease.Activation and mutation of NLRP3 can cause severe inflammation in diseases such as chronic infantile neurologic cutaneous and articular syndrome,Muckle-Wells syndrome,and familial cold autoinflammatory syndrome 1.To date,a great effort has been made to decode the underlying mechanisms of NLRP3 activation.The priming and activation of NLRP3 drive the maturation and release of active interleukin(IL)-18 and IL-1βto cause inflammation and pyroptosis,which can significantly trigger many diseases including inflammatory diseases,immune disorders,metabolic diseases,and neurodegenerative diseases.The investigation of NLRP3 as a therapeutic target for disease treatment is a hot topic in both preclinical studies and clinical trials.Developing potent NLRP3 inhibitors and downstream IL-1 inhibitors attracts wide-spectrum attention in both research and pharmaceutical fields.In this minireview,we first updated the molecular mechanisms involved in NLRP3 inflammasome activation and the associated downstream signaling pathways.We then reviewed the molecular and cellular pathways of NLRP3 in many diseases,including obesity,diabetes,and other metabolic diseases.In addition,we briefly reviewed the roles of NLRP3 in cancer growth and relative immune checkpoint therapy.Finally,clinical trials with treatments targeting NLRP3 and its downstream signaling pathways were summarized.
基金We thank Professor McGuckin M(MMRI,Brisbane)for providing human colon cancer cell lines(Caco-2,LoVo,and SW480)Dr.Rolfe B(AIBN,Brisbane)for providing mouse NSC-34 cells.
文摘BACKGROUND Colon cancer cell lines are widely used for research and for the screening of drugs that specifically target the stem cell compartment of colon cancers.It was reported that colon cancer carcinoma specimens contain a subset of leucine-rich repeatcontaining G protein-coupled receptor 5(LGR5)-expressing stem cells,these socalled“tumour-initiating”cells,reminiscent in their properties of the normal intestinal stem cells(ISCs),may explain the apparent heterogeneity of colon cancer cell lines.Also,colon cancer is initiated by aberrant Wnt signaling in ISCs known to express high levels of LGR5.Furthermore,in vivo reports demonstrate the clonal expansion of intestinal adenomas from a single LGR5-expressing cell.AIM To investigate whether colon cancer cell lines contain cancer stem cells and to characterize these putative cancer stem cells.METHODS A portable fluorescent reporter construct based on a conserved fragment of the LGR5 promoter was used to isolate the cell compartments expressing different levels of LGR5 in two widely used colon cancer cell lines(Caco-2 and LoVo).These cells were then characterized according to their proliferation capacity,gene expression signatures of ISC markers,and their tumorigenic properties in vivo and in vitro.RESULTS The data revealed that the LGR5 reporter can be used to identify and isolate a classical intestinal crypt stem cell-like population from the Caco-2,but not from the LoVo,cell lines,in which the cancer stem cell population is more akin to B lymphoma Moloney murine leukemia virus insertion region 1 homolog(+4 crypt)stem cells.This sub-population within Caco-2 cells exhibits an intestinal cancer stem cell gene expression signature and can both self-renew and generate differentiated LGR5 negative progeny.Our data also show that cells expressing high levels of LGR5/enhanced yellow fluorescent protein(EYFP)from this cell line exhibit tumorigenic-like properties in vivo and in vitro.In contrast,cell compartments of LoVo that are expressing high levels of LGR5/EYFP did not show these stem cell-like properties.Thus,cells that exhibit high levels of LGR5/EYFP expression represent the cancer stem cell compartment of Caco-2 colon cancer cells,but not LoVo cells.CONCLUSION Our findings highlight the presence of a spectrum of different ISC-like compartments in different colon cancer cell lines.Their existence is an important consideration for their screening applications and should be taken into account when interpreting drug screening data.We have generated a portable LGR5-reporter that serves as a valuable tool for the identification and isolation of different colon cancer stem cell populations in colon cancer lines.
基金Supported by Sanming Project of Shenzhen,No.SZSM201612041Shenzhen Science and Technology Innovation Commission Project,No.GJHZ20180420180754917 and No.ZDSYS20190902092855097Postdoctoral Science Foundation of China,No.2018M633095.
文摘BACKGROUND Cancer stem cells(CSCs)are a subpopulation of cancer cells with the potential of self-renewal and differentiation.CSCs play critical roles in tumorigenesis,recurrence,metastasis,radiation tolerance and chemoresistance.AIM To assess the expression patterns and clinical potential of doublecortin-like kinase 1(DCLK1)and leucine-rich repeat-containing G-protein-coupled receptor 5(Lgr5),as prognostic CSC markers of colorectal cancer(CRC).METHODS The expression of DCLK1 and Lgr5 in CRC tissue sections from 92 patients was determined by immunohistochemistry.Each case was evaluated using a combined scoring method based on signal intensity staining(scored 0-3)and the proportion of positively stained cancer cells(scored 0-3).The final staining score was calculated as the intensity score multiplied by the proportion score.Low expression of DCLK1 and Lgr5 was defined as a score of 0-3;high expression of DCLK1 and Lgr5 was defined as a score of≥4.Specimens were categorized as either high or low expression,and the correlation between the expression of DCLK1 or Lgr5 and clinicopathological factors was investigated.RESULTS DCLK1 and Lgr5 expression levels were significantly positively correlated.CRC patients with high DCLK1,Lgr5 and DCLK1/Lgr5 expressions had poorer progression-free survival and overall survival.Moreover,high expression of DCLK1 was an independent prognostic factor for recurrence and overall survival in patients with CRC by multivariate analysis(P=0.026 and P=0.049,respectively).CONCLUSION DCLK1 may be a potential CSC marker for the recurrence and survival of CRC patients.
文摘Aim： To investigate the role of CAG and GGN repeats as genetic background affecting androgen insensitivity syndrome （AIS） phenotype. Methods： We analyzed lengths of androgen receptor （AR）-CAG and GGN repeats in 69 AIS cases, along with 136 unrelated normal male individuals. The lengths of repeats were analyzed using polymerase chain reaction （PCR） amplification followed by allelic genotyping to determine allele length. Results： Our study revealed significantly shorter mean lengths of CAG repeats in patients （mean 18.25 repeats, range 14-26 repeats） in comparison to the controls （mean 22.57 repeats, range 12-39 repeats） （two-tailed P 〈 0.0001）. GGN repeats, however, did not differ significantly between patients （mean 21.48 repeats） and controls （mean 21.21 repeats） （two- tailed P = 0.474）. Among patients＇ groups, the mean number of CAG repeats in partial androgen insensitivity cases （mean 15.83 repeats） was significantly less than in complete androgen insensitivity cases （mean 19.46 repeats） （two- tailed P 〈 0.0001）. Conclusion： The findings suggest that shorter lengths of repeats in the AR gene might act as low penetrance genetic background in varying manifestation of androgen insensitivity.
基金a Ph D fellowship by FCT-Fundacao para a Ciência Tecnologia (SFRH/BD/135868/2018)(to SSC)。
文摘Axonal growth inhibitors are released during traumatic injuries to the adult mammalian central nervous system, including after spinal cord injury. These molecules accumulate at the injury site and form a highly inhibitory environment for axonal regeneration. Among these inhibitory molecules, myelinassociated inhibitors, including neurite outgrowth inhibitor A, oligodendrocyte myelin glycoprotein, myelin-associated glycoprotein, chondroitin sulfate proteoglycans and repulsive guidance molecule A are of particular importance. Due to their inhibitory nature, they represent exciting molecular targets to study axonal inhibition and regeneration after central injuries. These molecules are mainly produced by neurons, oligodendrocytes, and astrocytes within the scar and in its immediate vicinity. They exert their effects by binding to specific receptors, localized in the membranes of neurons. Receptors for these inhibitory cues include Nogo receptor 1, leucine-rich repeat, and Ig domain containing 1 and p75 neurotrophin receptor/tumor necrosis factor receptor superfamily member 19(that form a receptor complex that binds all myelin-associated inhibitors), and also paired immunoglobulin-like receptor B. Chondroitin sulfate proteoglycans and repulsive guidance molecule A bind to Nogo receptor 1, Nogo receptor 3, receptor protein tyrosine phosphatase σ and leucocyte common antigen related phosphatase, and neogenin, respectively. Once activated, these receptors initiate downstream signaling pathways, the most common amongst them being the Rho A/ROCK signaling pathway. These signaling cascades result in actin depolymerization, neurite outgrowth inhibition, and failure to regenerate after spinal cord injury. Currently, there are no approved pharmacological treatments to overcome spinal cord injuries other than physical rehabilitation and management of the array of symptoms brought on by spinal cord injuries. However, several novel therapies aiming to modulate these inhibitory proteins and/or their receptors are under investigation in ongoing clinical trials. Investigation has also been demonstrating that combinatorial therapies of growth inhibitors with other therapies, such as growth factors or stem-cell therapies, produce stronger results and their potential application in the clinics opens new venues in spinal cord injury treatment.
文摘This study aimed to investigate the correlations among androgen receptor （AR） CAG repeat polymorphism, sex hormones and penile length in healthy Chinese young adult men. Two hundred and fifty-three healthy men （aged 22.8 ± 3.1years） were enrolled. The individuals were grouped as CAG short （CAGs） if they harbored repeat length of 〈20 or as CAG long （CAGL） if their CAG repeat length was 〉20. Body height/weight, penile length and other parameters were examined and recorded by the specified physicians; CAG repeat polymorphism was determined by the polymerase chain reaction （PCR） method; and the serum levels of the sex hormones were detected by radioimmunoassay. Student＇s t-test or linear regression analysis was used to assess the associations among AR CAG repeat polymorphism, sex hormones and penile length. This investigation showed that the serum total testosterone （T） level was positively associated with the AR CAG repeat length （P = 0.01）; whereas, no significant correlation of T or AR CAG repeat polymorphism with the penile length was found （P = 0.593）. Interestingly, an inverse association was observed between serum prolactin （PRL） levels and penile length by linear regression analyses （β = -0.024, P = 0.039, 95% confidence interval （CI）： -0.047, 0）. Collectively, this study provides the first evidence that serum PRL, but not T or AR CAG repeat polymorphism, is correlated with penile length in the Han adult population from northwestern China.
基金supported by National Institutes of Health grant AR066831-01ASBMR GAP grant to Weirong R Xingsupported by a senior research career scientist award from the Department of Veteran’s Affairs
文摘Leucine-rich repeat kinase 1 （LRRK1） plays a critical role in regulating cytoskeletal organization, osteoclast activity, and bone resorption with little effect on bone formation parameters. Deficiency of Lrrkl in mice causes a severe osteopetrosis in the metaphysis of the long bones and vertebrae bones, which makes LRRK1 an attractive alternative drug target for the treatment of osteoporosis and other high-turnover bone diseases. This review recent advances on the functions of the Lrrkl-related family members, Lrrkl deficiency-induced skeletal phenotypes, LRRK1 structure-function, potential biological substrates and interacting proteins, and the mechanisms of LRRK1 action in osteoclasts.
基金the National Natural Science Foundation of China, No. 30973072Independent Research Project of Wuhan University for Graduate Students, No. 201130202020001Fundamental Research Funds for the Central Universities
文摘Leucine-rich repeats and immunoglobulin-like domains 1 （LRIG1） is an anti-oncogene. LRIG1 is correlated with Bcl-2 in ependymomas. Decreased Bcl-2 and manganese superoxide dismutase expression can improve the chemosensitivity of glioma. In the present study, a tissue microarray of human brain astrocytomas was constructed. To investigate the relationship of LRIG1 with Bcl-2 and manganese superoxide dismutase, LRIG1, Bcl-2 and manganese superoxide dismutase expression in our tissue microarray was determined using immunohistochemistry. In addition, we constructed the LRIG1-U251 cell line, and its responses to doxorubicin and temozolomide were detected using the MTT assay. Results showed that LRIG1 expression was significantly negatively correlated with Bcl-2 and manganese superoxide dismutase expression in glioma. Also, proliferation of LRIG1-U251 cells exposed to doxorubicin or temozolomide was significantly inhibited, i.e. in the LRIG1-U251 cell line, the chemosensitivity to doxorubicin and temozolomide was increased. This indicates that increased LRIG1 expression produces a chemosensitivity in glioma.
基金the Swedish Institute, No. 00287/2006210the North Sweden Cancer Foundation, Specialized Research Fund for the Doctoral Program New Teacher of Higher Education by the Chinese Ministry of Education, No. 200804861039the National Natural Science Foundation of China, No. 30973073, 30973072
文摘The current study investigated correlations between the expression of leucine-rich repeats and immunoglobulin-like domain 1 （LRIG1） and antioxidant enzymes and related proteins, including manganese superoxide dismutase, glutamate cysteine ligase catalytic or regulatory subunit, thioredoxin and thioredoxin reductase, in both human ependymoma and oligodendroglioma. Results revealed that the cytoplasmic expression of LRIG1 was associated with expression of glutamate cysteine ligase catalytic subunit in the human ependymoma, while the nuclear expression of LRIG1 was associated with expression of thioredoxin reductase. In human oligodendroglioma, the cytoplasmic expression of LRIG1 was associated with expression of the glutamate cysteine ligase catalytic subunit. Both the nuclear and perinuclear expressions of LRIG1 were associated with expression of glutamate cysteine ligase regulatory subunit. These results indicated that several antioxidant enzymes and related proteins contributed to LRIG1 expression, and that these may participate in the antioxidation of the cells.
基金Supported by the Key Research and Development Program of Anhui Province,No.202104J07020029.
文摘BACKGROUND F-box and leucine-rich repeat 6(FBXL6)have reportedly been associated with several cancer types.However,the role and mechanisms of FBXL6 in gastric cancer(GC)require further elucidation.AIM To investigate the effect of FBXL6 in GC tissues and cells and the underlying mechanisms.METHODS TCGA and GEO database analysis was performed to evaluate the expression of FBXL6 in GC tissues and adjacent normal tissues.Reverse transcription-quantitative polymerase chain reaction,immunofluorescence,and western blotting were used to detect the expression of FBXL6 in GC tissue and cell lines.Cell clone formation,5-ethynyl-2’-deoxyuridine(EdU)assays,CCK-8,transwell migration assay,and wound healing assays were performed to evaluate the malignant biological behavior in GC cell lines after transfection with FBXL6-shRNA and the overexpression of FBXL6 plasmids.Furthermore,in vivo tumor assays were performed to prove whether FBXL6 promoted cell proliferation in vivo.RESULTS FBXL6 expression was upregulated more in tumor tissues than in adjacent normal tissues and positively associated with clinicopathological characteristics.The outcomes of CCK-8,clone formation,and Edu assays demonstrated that FBXL6 knockdown inhibited cell proliferation,whereas upregulation of FBXL6 promoted proliferation in GC cells.Additionally,the transwell migration assay revealed that FBXL6 knockdown suppressed migration and invasion,whereas the overex pression of FBXL6 showed the opposite results.Through the subcutaneous tumor implantation assay,it was evident that the knockdown of FBXL6 inhibited GC graft tumor growth in vivo.Western blotting showed that the effects of FBXL6 on the expression of the proteins associated with the epithelial-mesenchymal transition-associated proteins in GC cells.CONCLUSION Silencing of FBXL6 inactivated the EMT pathway to suppress GC malignancy in vitro.FBXL6 can potentially be used for the diagnosis and targeted therapy of patients with GC.
文摘Leucine rich repeats (LRRs) are present in over 14,000 proteins that have been identified in viruses, bacteria, archaea, and eukaryotes. Two to sixty-two LRRs occur in tandem forming an overall arc shaped domain. There are eight classes of LRRs. Plant specific LRRs (class: PS-LRR) had previously been recognized in only plant proteins. However, we find that PS-LRRs are also present in proteins from bacteria. We investigated the origin of bacterial PS-LRR domains. PSLRR proteins are widely distributed in most plants;they are found in only a few bacterial species. There are no PS-LRR proteins from archaea. Bacterial PS-LRRs in twenty proteins from eleven bacterial species (in the three phyla: Proteobacteria, Cyanobacteria, and Bacteroidetes) are significantly more similar to the PS-LRR class than to the other seven classes of LRR proteins. Not only amino acid sequences but also nucleotide sequences of the bacterial PS-LRR domains show highly significant similarity with those of many plant proteins. The program, EGID (Ensemble algorithm for Genomic Island Detection), predicts that Synechococcus sp. CYA_ 1022 came from another organism. Four bacterial PS-LRR proteins contain AhpC-TSA, IgA peptidase M64, the immunoglobulin domain, the Calx-b domain, and the He_PIG domain;these domains show no similarity with any eukaryotic (plant) proteins, in contrast to the similarities of their respective PS-LRRs. The present results indicate that horizontal gene transfer (HGT) of genes/gene fragments encoding PS-LRR domains occurred between bacteria and plants, and HGT among the eleven bacterial species, of the three phyla, as opposed to descent from a common ancestor. There is the possibility of the occurrence of one HGT event from plant to bacteria. A series of HGTs might then have occurred recently and rapidly among these eleven species of bacteria.
文摘AIM： To investigate the mechanism underlying the loss of responsiveness to anti-vascular endothelial growth factor（VEGF） treatment after repeated injections for choroidal neovascularization, VEGF and VEGF receptor（VEGFR） expressions were evaluated following repeated bevacizumab treatments in hypoxic human umbilical vein endothelial cells（HUVECs） in vitro.METHODS： HUVECs were incubated under hypoxic conditions in two media of different bevacizumab concentrations（1.0 or 2.5 mg/m L） for 17 h, and then in a new medium without bevacizumab for 7h. This procedure was repeated twice more. A culture with an identical volume of excipients served as the control. Cytotoxicity and cell proliferation were assessed using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide and Ki-67 assays, respectively. Levels of VEGF and VEGFR were assessed using enzyme-linked immunosorbent assay and Western blot respectively.RESULTS： Cytotoxic effects were not reported for either bevacizumab concentration. Cell proliferation was not reduced after anti-VEGF treatments. VEGF level after single treatment was significantly higher than that of the control and after repeated treatments. Phosphorylated VEGFR-2 expression increased significantly after singleand repeated bevacizumab treatments compared with the control. The 1.0 mg/m L bevacizumab induced significantly higher expressions of VEGFR-2 than the 2.5 mg/m L in single and repeated treatment groups.CONCLUSION： Bevacizumab treatment of HUVECs elevated VEGFR expression in both single and repeated treatments, indicating a mechanism for the reduced efficacy of anti-VEGF therapy in ocular neovascular disorders.
基金funded by a Grant-in-Aid for Scientific Research(C)from the Japan Society for the Promotion of Sciences and Health Labor Sciences Research Grant.
文摘We investigated the influence of the cytosine-adenine (CA) dinucleotide repeat polymorphism in intron 6 of estrogen receptor β (ERβ) gene on rheumatoid arthritis (RA) risk. One hundred and ninety-three RA patients and 77 control subjects with osteoarthritis (OA) were recruited. The CA repeat polymorphism was assayed by a dye-terminator cycle sequencing analysis. No statistically significant difference in the mean number of CA repeats between the RA and OA patients was observed (RA: 21.47, OA: 21.23, P = 0.324). The alleles were categorized according to the number of repeats: short (S, ≦21) and long (L, ≧22), in which the genotypes SS, SL, and LL were observed. No significant differences were observed for the allele and genotype distributions of this polymorphism in both patient groups. The RA patients were classified according to RA severity: mild (least erosive disease) and severe (more erosive and mutilating disease). Again, no significant difference in genotype frequency between these groups was observed, even after stratifying by sex. The present study indicates that additional studies are needed to clarify the roles of this polymorphism, estrogen, and ER in the development of autoimmune diseases.
文摘Androgen receptor （AR） gene has been extensively studied in diverse clinical conditions. In addition to the point mutations, trinucleotide repeat （CAG and GGN） length polymorphisms have been an additional subject of interest and controversy among geneticists. The polymorphic variations in triplet repeats have been associated with a number of disorders, but at the same time contradictory findings have also been reported. Further, studies on the same disorder in different populations have generated different results. Therefore, combined analysis or review of the published studies has been of much value to extract information on the significance of variations in the gene in various clinical conditions. AR genetics has been reviewed extensively but until now review articles have focused on individual clinical categories such as androgen insensitivity, male infertility, prostate cancer, and so on. We have made the first effort to review most the aspects of AR genetics. The impact of androgens in various disorders and polymorphic variations in the AR gene is the main focus of this review. Additionally, the correlations observed in various studies have been discussed in the light of in vitro evidences available for the effect of AR gene variations on the action of androgens.
文摘The HIV-1 LTR controls the expression of HIV-1 viral genes and thus is critical for viral propagation and pathology. Numerous host factors have been shown to participate in the regulation of the LTR promoter. Among them is the thyroid hormone (T3) receptor (TR). TR has been shown to bind to the critical region of the promoter that contain the NFbB and Sp1 binding sites. Interestingly, earlier transient transfection studies in tissue culture cells have yielded contradicting conclusions on the role of TR in LTR regulation, likely due to the use of different cell types and/or lack of proper chromatin organization. Here, using the frog oocyte as a model system that allows replication-coupled chromatin assembly, mimicking that in somatic cells, we demonstrate that unliganded heterodimers of TR and RXR (9-cis retinoic acid receptor) repress LTR while the addition of T3 relieves the repression and further activates the promoter. More importantly, we show that chromatin and unliganded TR/RXR synergize to repress the promoter in a histone deacetylase-dependent manner.
基金Cell Analysis Laboratory, 2nd Department of Internal Medicine, and the 1st Department of Pathology and Experimental Oncology, Semmelweis University for their technical support
文摘AIM:To characterize the regeneration-associated stem cell-related phenotype of hepatocyte-derived growth factor receptor(HGFR)-expressing cells in active ulcerative colitis(UC).METHODS:On the whole 38 peripheral blood samples and 38 colonic biopsy samples from 18 patients with histologically proven active UC and 20 healthy control subjects were collected.After preparing tissue microarrays and blood smears HGFR,caudal type homeobox 2(CDX2),prominin-1(CD133) and Musashi-1conventional and double fluorescent immunolabelings were performed.Immunostained samples were digitalized using high-resolution Mirax Desk instrument,and analyzed with the Mirax TMA Module software.For semiquantitative counting of immunopositive lamina propria(LP) cells 5 fields of view were counted at magnification x 200 in each sample core,then mean ± SD were determined.In case of peripheral blood smears,30 fields of view with 100 μm diameter were evaluated in every sample and the number of immunopositive cells(mean ± SD) was determined.Using 337 nm UVA Laser MicroDissection system at least 5000 subepithelial cells from the lamina propria were collected.Gene expression analysis of HGFR,CDX2,CD133,leucine-rich repeat-containing G-protein coupled receptor 5(Lgr5),Musashi-1 and cytokeratin20(CK20) were performed in both laser-microdisscted samples and blood samples by using real time reverse transcription polymerase chain reaction(RT-PCR).RESULTS:By performing conventional and double fluorescent immunolabelings confirmed by RT-PCR,higher number of HGFR(blood:6.7 ± 1.22 vs 38.5 ±3.18;LP:2.25 ± 0.85 vs 9.22 ± 0.65;P < 0.05),CDX2(blood:0 vs 0.94 ± 0.64;LP:0.75 ± 0.55 vs 2.11± 0.75;P < 0.05),CD133(blood:1.1 ± 0.72 vs 8.3± 1.08;LP:11.1 ± 0.85 vs 26.28 ± 1.71;P < 0.05)and Musashi-1(blood and LP:0 vs scattered) positive cells were detected in blood and lamina propria of UC samples as compared to controls.HGFR/CDX2(blood:0 vs 1± 0.59;LP:0.8 ± 0.69 vs 2.06 ± 0.72,P < 0.05)and Musashi-1/CDX2(blood and LP:0 vs scattered) coexpressions were found in blood and lamina propria of UC samples.HGFR/CD133 and CD133/CDX2 coexpressions appeared only in UC lamina propria samples.CDX2,Lgr5 and Musashi-1 expressions in UC blood samples were not accompanied by CK20 mRNA expression.CONCLUSION:In active UC,a portion of circulating HGFR-expressing cells are committed to the epithelial lineage,and may participate in mucosal regeneration by undergoing mesenchymal-to-epithelial transition.
