摘要
Objective The aim of this study was to investigate the methylation status of fragile histidine triad( FHIT) gene, human mutl homolog 1(hMLH1)gene,p16 gene,retinoic acid receptor beta( RAR-beta) gene,Reprimo gene and tissue inhibitor of metalloproteinase 3 ( Timp3) gene in gastric cancer and corresponding paracancerous tissues. Methods The methylation levels of FHIT,hMLH1,p16,RAR-beta,Reprimo and TIMP3 genes in 42 clinically resected gastric cancer specimens and 42 corresponding paracancerous tissues were detected by sodium bisulfite sequencing. Results The average methylation rates of the genes in gastric cancer and corresponding paracancerous tissues were:FHIT(1. 50% ,1. 36% ),hMLH1(4. 77% ,0. 48% ),p16(9. 63% ,10. 36% ), RAR-beta(4. 75% ,4. 17% ),Reprimo(9. 71% ,3. 76% )and TIMP3 genes(18. 34% ,14. 06% ). Compared with the paracancerous control group,the average methylation rate of Reprimo gene was only statistically different in gastric cancer patients(P=0. 00787). The difference in methylation rate of Reprimo gene promoter in gastric cancer patients with the degree of tissue differentiation was sta-tistically significant(P<0. 05). Conclusion There has methylation in the cytosine guanidine dinucleotide island of the Reprimo gene promoter region in gastric cancer. The high methylation rate of the Reprimo gene can be used as a potential biomarker for gastric cancer to detect the early stage of gastric cancer.
摘要
BACKGROUND: Reprimo (RPRM), a highly glycosylated protein, is a new downstream effector of p53-induced cell cycle arrest at the G2/M checkpoint, and a putative tumor suppressor gene frequently silenced via methylation of its promoter region in several malignances. The aim of this study was to characterize the epigenetic inactivation and its biological function in BC cell lines. METHODS: The correlation between RPRM methylation and loss of mRNA expression was assessed in six breast cancer cell lines by methylation specific PCR (MSP), 5'-Aza-2'-deoxycytidine treatment and RT-PCR assays. MDA-MB-231 cells were chosen to investigate the phenotypic effect of RPRM in cell proliferation, cell cycle, cell death, cell migration and invasion. RESULTS: In the cancer methylome system (CMS) (web-based system for visualizing and analyzing genome-wide methylation data of human cancers), the CpG island region of RPRM (1.1 kb) was hypermethylated in breast cancer compared to normal breast tissue; more interesting still was that ERa(+) tumors showed higher methylation intensity than ERa(-). Downregulation of RPRM mRNA by methylation was confirmed in MDA-MB-231 and BT-20 cell lines. In addition, overexpression of RPRM in MDA-MB-231 cells resulted in decreased rates of cell migration, wound healing and invasion in vitro. However, RPRM overexpression did not alter cell viability, phosphatidylserine (PS) translocation or G2/M cell cycle transition. CONCLUSION: Taken together, these data suggest that RPRM is involved in decreased cell migration and invasion in vitro, acting as a potential tumor suppressor gene in the MDA-MB-231 cell line.
Subject(s)
Female , Humans , Breast Neoplasms/pathology , Cell Cycle Proteins/physiology , Cell Movement/physiology , Cell Proliferation/physiology , Glycoproteins/physiology , Analysis of Variance , Blotting, Western , Breast Neoplasms/genetics , Cell Cycle , Cell Line, Tumor , Cell Survival , Cell Cycle Proteins/genetics , Cell Movement/genetics , Cell Proliferation/genetics , DNA Methylation , Epigenesis, Genetic , Gene Expression Regulation, Neoplastic , Glycoproteins/genetics , Neoplasm Invasiveness , Real-Time Polymerase Chain Reaction , Statistics, Nonparametric摘要
Objective To investigate the Reprimo and hMLH1 gene promoter methylation detection value in the diagnosis of early gastric cancer.Methods Chose patints in Shaanxi Provincial People’s Hospital from September 2013 to April 2014,50 cases of patients with chronic atrophicgastritis with intestinal metaplasia,50 cases of patients with gastricmucosal atypical hyperplasia,50 patients with gastric cancer,endoscopic gastric biopsy samples,and 30 cases of normal gastric mucosa biopsy tissues as control group.Analysis abnormal expression in Reprimo gene and hMLH1 genes promoter methylation,compared the differences.between groups of patients.Results The patients with gastric mucosatissues Reprimo and hMLH1 genes promoter methylation positive rate was significantly higher than that of normal group,the difference wasstatistically signifi-cant (P<0.05).Reprimo gene promoter methylation were:patients with chronic atrophic gastritis with intestinal metaplasia 28% (χ2 =10.18,P < 0.05).Patients with gastric mucosalatypical hyperplasia 56% (χ2 = 25.84,P < 0.05)and patients with gastric cancer 62% (χ2 = 30.36,P < 0.05).hMLH1 gene promoter methylation were:patients with chronic atrophic gastritis with intestinal metaplasia 20% (χ2 =4.39,P <0.05),patients with gastric mucosal atypical hyperplasia 44% (χ2 =15.13,P <0.05)and patients with gastric cancer 48% (χ2 = 17.41,P <0.05),high specificity of detection.Conclusion Reprimo and hMLH1 gene’s detect value in the diagnosis of early gastric cancer is very high,high specificity,it is an effec-tive way of diagnosis,treatment in clinical diagnosis of patients with broad prospects.