Association of LncRNA MEG3 polymorphisms with efficacy of neoadjuvant chemotherapy in breast cancer.

BACKGROUND: Breast cancer is the most common malignancy in women, and neoadjuvant chemotherapy has been recommended to the patients with locally advanced breast cancer as the initial treatments. Long non-coding RNA (lncRNA) MEG3, an identified tumor suppressor, has been implicated in the development of various cancers. However, there is no data to evaluate the effect of MEG3 polymorphisms on neoadjuvant treatment in the breast cancer. METHODS: Genotyping was performed using Nanodispenser Spectro CHIP chip spotting and Mass ARRAY Compact System. Univariate and multivariate logistic regression analyses were used to analyze the associations between the MEG3 polymorphisms and the pathological complete response (pCR). The disease-free survival (DFS) was estimated by the Kaplan-Meier method, and multivariate Cox proportional hazards models were used to calculate the hazard ratios (HRs) with a 95% confidential interval (CI). RESULTS: A total of 144 patients with available pretreatment blood species were enrolled in the SHPD002 clinic trial of neoadjuvant chemotherapy for breast cancer. MEG3 rs10132552 were significantly associated with good response (Adjusted OR = 2.79, 95% CI 1.096-7.103, p = 0.031) in dominant model. Median follow-up time was 20 months. In multiple regression analysis, rs10132552 TC + CC (adjusted HR = 0.127, 95% CI 0.22-0.728, p = 0.02) and rs941576 AG + GG (adjusted HR = 0.183, 95% CI 0.041-0.807, p = 0.025) were significantly associated with good DFS. MEG3 rs7158663 (OR = 0.377, 95% CI 0.155-0.917, p = 0.032) were associated with a low risk of hemoglobin decrease in dominant models. CONCLUSIONS: LncRNA MEG3 polymorphisms were associated with the chemotherapy response and toxicity of paclitaxel and cisplatin. The result indicates that MEG3 polymorphisms can be considered as the predictive and prognostic markers for the breast cancer patients. TRIAL REGISTRATION: Retrospectively registered (ClinicalTrials. Gov identifier: NCT02221999 ); date of registration: Aug 20th, 2014.

Long non-coding RNA MEG3 silencing weakens high glucose-induced mesangial cell injury by decreasing LIN28B expression by sponging and sequestering miR-23c.

BACKGROUND: Diabetic nephropathy (DN) is a common kidney disease in diabetic patients. Long non-coding RNA maternally expressed gene 3 (MEG3) and microRNA (miR)-23c are reported to be implicated in DN development. Nevertheless, it is unclear that the molecular mechanism between MEG3 and miR-23c in DN remains unclear. METHODS: Human mesangial cells (HMCs) were treated with high glucose (HG) to simulate the DN status in vitro. Expression of MEG3 and miR-23c was measured. Effects of MEG3 silencing on HG-stimulated HMC injury were determined. The relationship between MEG3 and miR-23c was verified by the dual-luciferase reporter and RNA immunoprecipitation assays. RESULTS: MEG3 was overexpressed in serums from DN patients and HG-stimulated HMCs. MEG3 knockdown weakened HG-stimulated HMC proliferation, extracellular matrix (ECM) accumulation, and inflammation. MEG3 regulated lin-28 homolog B (LIN28B) expression through adsorbing miR-23c. MiR-23c inhibitor reversed MEG3 knockdown-mediated effects on HG-stimulated HMC proliferation, ECM accumulation, and inflammation. LIN28B overexpression overturned miR-23c mimic-mediated effects on HG-stimulated HMC proliferation, ECM accumulation, and inflammation. CONCLUSION: MEG3 regulated HMC injury via regulation of the miR-23c/LIN28B axis in DN, which can help us better understand the mechanism of DN mediated by MEG3.