ABSTRACT
UNLABELLED: Circulating microRNAs show aberrant expression in patients with cancer. The aim of this study was to investigate the prognostic value of circulating microRNA-21 (miR-21) in digestive system cancers. METHODS: All the eligible studies were searched by Medline and EMBASE. The hazard ratios (HRs) for overall survival (OS), which compared the expression levels of circulating miR-21 in patients with digestive cancer was extracted and estimated. Pooled HRs and 95% confidence intervals (CI) were calculated. Then a meta-analysis was performed to clarify the prognostic value of the miR-21. RESULTS: A total of seven studies involving 907 subjects were included. The results suggested that higher circulating miR-21 could predict worse OS outcome with the pooled HR of 2.19 (95% CI 1.01-4.75, P = 0.05) in digestive system cancers. Subgroup analysis by ethnicity indicated circulating miR-21 was associated with OS in patients with digestive cancer among Asians with the pooled HR of 2.90 (95% CI 1.30-6.45, P = 0.009). However, subgroup analysis by digestive system site revealed that there is no associated with OS in patients with colorectal cancer with the pooled HR of 1.34 (95% CI 0.45-4.00, P = 0.60). CONCLUSION: The present findings suggest that circulating miR-21 is associated with poor survival in patients with digestive cancer and could be a prognostic biomarker for those patients.
ABSTRACT
OBJECTIVE: To study the effect of the transfected Breast cancer metastasis suppressor 1 (BRMS1) gene on the migration of breast cancer cells and the possible mechanisms involved. METHODS: MDA-MB-231HM cells which have a high propensity of metastasize to lung was sieved from MDA-MB-231 and its derivative cells stable transfected with BRMS1 were used to study in vitro. Cell migratory ability was observed. The cellular cyclic adenylic acid (cAMP) concentration was tested by radioimmunoassay (RIA). The activity of adenylate cyclase (AC), phosphodiesterase (PDE) and protein kinase A (PKA) were measured by enzyme immunoassay (EIA) and (γ-(32)P) ATP incorporation. The effect of BRMS1 on connexins (Cx) expression was analyzed by by RT-PCR and Western blot. RESULTS: Overexpression of BRMS1 significantly inhibited cell migration in MDA-MB-231HM cells in vitro. However, BRMS1's effect on cell migration could be eliminated after pretreating with pertussis toxin (PTX). BRMS1 overexpression increased cellular cAMP and PKA activity by activating the activity of AC. Furthermore, BRMS1 overexpression up-regulated Cx26 expression, whereas Cx32, Cx43 expressions did not changed. CONCLUSION: The present study indicated G-protein-coupled cAMP signaling pathway was involved in BRMS1 related MDA-MB-231HM cells migration, and BRMS1 could change connexins (Cx) expression profiles through increasing expression of Cx26 in cells.
