MicroRNA-301b-3p accelerates the growth of gastric cancer cells by targeting zinc finger and BTB domain containing 4

MicroRNAs (miRNAs) have been found to be aberrantly expressed and exert essential roles in the tumorigenesis and progression of gastric cancer (GC). miR-301b-3p has been recognized as a cancer-related miRNA in lung cancer, bladder cancer and hepatocellular carcinoma. However, the function of miR-301b-3p in GC progression and its underlying mechanism have not been studied yet. In this study, we found that miR-301b-3p expression was up-regulated in GC tissues compared to adjacent noncancerous tissues. Furthermore, the elevated levels of miR-301b-3p were detected in GC cell lines (SGC-7901, AGS, MKN-45 and MGC-803) as compared with GES-1 cells. Interestingly, GC tissues from patients with tumor size ≥ 5 cm and advanced tumor stages showed obvious higher levels of miR-301b-3p compared to matched controls. Functionally, miR-301b-3p knockdown prominently inhibited cell proliferation, and induced cell cycle arrest at G1 phase and apoptosis in MGC-803 cells. Meanwhile, ectopic expression of miR-301b-3p conversely regulated these biological behaviors of MKN-45 cells. Next, we found that miR-301b-3p knockdown increased, whereas miR-301b-3p overexpression reduced the expression of zinc finger and BTB domain containing 4 (ZBTB4) in GC cells. Accordingly, luciferase reporter assay identified ZBTB4 as a direct target of miR-301b-3p. ZBTB4 overexpression markedly restrained the growth of MGC-803 cells. More importantly, ZBTB4 silencing partially reversed miR-301b-3p knockdown-induced tumor suppressive effects on MGC-803 cells. In conclusion, we firstly revealed that miR-301-3p was highly expressed in GC and contributed to tumor progression via attenuating ZBTB4, which might provide a novel molecular-targeted strategy for GC treatment.     

汽车制造工人颈部职业性肌肉骨骼疾患及危险因素探讨

目的调查汽车制造工人职业性肌肉骨骼疾患(WMSDs)发病情况，探讨其颈部WMSDs的危险因素。方法采用整群抽样方法，选择广州市1家汽车整车及1家零部件生产企业共8356名作业人员为研究对象，采用《北欧肌肉骨骼疾患问卷(修改版)》(NMQ)调查WMSDs患病情况，多因素Logistic回归分析颈部WMSDs影响因素，并对危险因素接触情况进行调査分析。结果研究对象WMSDs年患病率为44.6%，其中颈部WMSDs患病率为25.4%(2126/8356)，以发动机生产及总装岗位作业工人的颈部WMSDs较高，年患病率分别为30.6%、26.3%。多因素Logistic回归分析结果显示，颈部WMSDs的主要危险因素包括年龄、工龄、以不舒服的姿势工作、每天从事同样的工作、涉及到寒冷凉风或气温变化、经常加班、腰背部经常重复同一动作、颈部前倾或后仰、颈部长时间保持同一姿势。调查发现，84.9%的研究对象每天从事同样的工作，总装岗位最高(89.0%)；83.5%的作业工人经常加班；81.6%的作业工人工作中颈部前倾或后仰，以发动机生产岗位最为突出(87.5%)。结论汽车制造作业人员WMSDs患病率较高，尤以颈部最为常见，其危险因素主要包括不良工作姿势及不合理的劳动组织，发动机生产及总装岗位是颈部WMSDs的重点风险岗位，应开展有效的工效学干预措施。