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BACKGROUND/AIMS: The role of DHRS3 in human cancer remains unclear. Our study explored the role of DHRS3 in gastric cancer (GC) and its clinicopathological significance and associated mechanisms. MATERIALS: Bisulfite-assisted genomic sequencing PCR and a Mass-Array system were used to evaluate and quantify the methylation levels of the promoter. The expression levels and biological function of DHRS3 was examined by both in vitro and in vivo assays. A two-way hierarchical cluster analysis was used to classify the methylation profiles, and the correlation between the methylation status of the DHRS3 promoter and the clinicopathological characteristics of GC were then assessed. RESULTS: The DHRS3 promoter was hypermethylated in GC samples, while the mRNA and protein levels of DHRS3 were significantly downregulated. Ectopic expression of DHRS3 in GC cells inhibited cell proliferation and migration in vitro, decreased tumor growth in vivo. DHRS3 methylation was correlated with histological type and poor differentiation of tumors. GC patients with high degrees of CpG 9.10 methylation had shorter survival times than those with lower methylation. CONCLUSION: DHRS3 was hypermethylated and downregulated in GC patients. Reduced expression of DHRS3 is implicated in gastric carcinogenesis, which suggests DHRS3 is a tumor suppressor.
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Objective To investigate the abnormal expression of microRNA (miRNA)-25 in the serum of gastric cancer patients and its clinical significance. Methods In Xijing Hospital of Digestive Diseases,Fourth Military Medical University,86 gastric cancer patients with operation and completed follow-up data,70 gastric adenoma patients and 80 healthy controls were selected as study objects.Total RNA was isolated from the serum. After the stable and sensitive miRNA-25 absolute quantity detection method established,the serum levels of miRNA-25 in gastric carcinoma patients,gastric adenoma patients and healthy controls were tested according to this method. The expression differences of miRNA-25 in the serum of patients with gastric cancer and gastric adenoma and healthy controls were analyzed with statistic analysis,and the correlation between miRNA-25 expression level and clinic pathological features of gastric cancer was also analyzed. Results The expression level of miRNA-25 in the serum of gastric cancer patients (135. 6 fmol/μg total RNA) was significantly higher than that of gastric adenoma patients (67. 7 fmol/μg total RNA) and healthy controls (62. 2 fmol/μg total RNA)(P＜0. 01). The receiver operating characterisstic curve of miRNA-25 indicated that serum miRNA-25 with good specificity and sensitivity in gastric cancer diagnosis (AUC=0. 827). The serum level of miRNA-25 in gastric cancer patients with lymph node metastasis [(148. 3±10. 2) fmol/μg total RNA] or clinicopathological stage Ⅲ /Ⅳ patients [(146. 7±9.5) fmol/μg total RNA] was significantly higher than that of gastric cancer patients without lymph node metastasis [(120. 3±10. 1)fmol/μg total RNA] or clinicopathological stage Ⅰ/Ⅱpatients [(119. 4±12. 2) fmol/μg total RNA] (P＜0.05). The correlation statistical analysis result indicated that there was no significant difference in survival period between serum miRNA-25 highly expressed and lowly expressed gastric cancer patients (P＞0. 05).Conclusion Serum miRNA-25 testing maybe helpful in diagnosis and prognosis of gastric cancer.
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Vaccination, especially mucosal vaccination, is considered to be effective in the management of Helicobacter pylori infections. However, most antigens alone cannot induce immune responses when administered mucosally and need to be co-administered with adjuvants or delivery systems. The current research on the mucosal adjuvant and delivery systems of vaccine against H. pylori, including advantages and disadvantages, mechanisms and applications is discussed in this review. Mutants of cholera toxin (CT) and the heat labile enterotoxin of Escherichia coli (LT), CpG oligodeoxynucleotides, biocompatible and biodegradable polymers, and live attenuated bacterial vectors may be promising adjuvant and delivery systems for H. pylori vaccine.
