Extracellular vesicles transmitted miR-31-5p promotes sorafenib resistance by targeting MLH1 in renal cell carcinoma

Sorafenib provides survival benefits in patients with advanced renal cell carcinoma (RCC), but its use is hampered by acquired drug resistance. It is important to fully clarify the molecular mechanisms of sorafenib resistance, which can help to avoid, delay or reverse drug resistance. Extracellular vesicles (EVs) can mediate intercellular communication by delivering effector molecules between cells. Here, we studied whether EVs are involved in sorafenib resistance of RCC and its possible molecular mechanisms. Using differential centrifugation, EVs were isolated from established sorafenib-resistant RCC cells (786-0 and ACHN), and EVs derived from sorafenib-resistant cells were uptaken by sensitive parental RCC cells and thus promoted drug resistance. Elevated exogenous miR-31-5p within EVs effectively downregulated MutL homolog 1 (MLH1) expression and thus promoted sorafenib resistance in vitro. Mice experiments also confirmed that miR-31-5p could mediate drug sensitivity in vivo. In addition, low expression of MLH1 was observed in sorafenib-resistant RCC cells and upregulation of MLH1 expression restored the sensitivity of resistant cell lines to sorafenib. Finally, miR-31-5p level in circulating EVs of RCC patients with progressive disease (PD) during sorafenib therapy was higher when compared to that in the pretherapy status. In conclusion, EVs shuttled miR-31-5p can transfer resistance information from sorafenib-resistant cells to sensitive cells by directly targeting MLH1, and thus magnify the drug resistance information to the whole tumor. Furthermore, miR-31-5p and MLH1 could be promising predictive biomarkers and therapeutic targets to prevent sorafenib resistance.     

红景天苷通过TLR4调控DC提高T细胞对肺癌3LL细胞的杀伤力

目的：探讨红景天苷（salidroside，SAL）对树突状细胞（dendritic cell，DC）表型及细胞毒性T细胞（cytotoxic T lympho‐cyte，CTL）抗肿瘤能力的影响。方法：选用Lewis肺癌细胞株3LL、野生型C57BL/6和TLR4-/-C57BL/6小鼠，获取小鼠骨髓来源的DC前体细胞，经过培养分化成未成熟DC，收获第6天的DC，经磁珠分选后获得纯度较高的CD11c+DC。将细胞分成PBS组、SAL组和脂多糖（lipopolysaccharide，LPS）组，培养48 h后用流式细胞术检测SAL体外对DC表面分子、吞噬功能、TLR4通路和对T细胞杀伤能力的影响。结果：与 PBS 组比较，SAL组DC的表面分子CD80、CD86、MHC Ⅱ表达水平显著升高（均 P<0.05）、吞噬功能显著下降（P<0.05）、TLR4 表达水平显著升高（P<0.01）；与野生型组比较，TLR4-/-组DC经SAL或LPS处理后，其表面分子CD80、CD86、MHC Ⅱ的表达水平显著降低（均P<0.05）；与PBS组比较，SAL组刺激活化的CTL对肺癌3LL细胞的杀伤效应显著升高（P<0.05）。结论：SAL可以通过调控TLR4诱导DC成熟，从而提高T细胞的杀伤能力     

金水宝片联合依诺肝素对维持性血液透析患者血脂代谢的影响

目的：探究金水宝片联合依诺肝素对维持性血液透析患者血脂代谢的影响。方法：选取2018年12月至2019年3月马鞍山十七冶医院血液净化中心进行透析的患者154例作为研究对象，根据用药不同分为对照组和观察组,每组77例。对照组常规应用依诺肝素抗凝，观察组在对照组抗凝基础上加用金水宝片，各组均干预3个月，比较2组患者血脂变化及持续血液透析并发症发生情况。结果：治疗后，观察组患者三酰甘油、总胆固醇及低密度脂蛋白胆固醇水平下降，高密度脂蛋白胆固醇升高，与治疗前比较差异均有统计学意义（P<0.05），与对照组治疗后比较，差异有统计学意义（P<0.05）；观察组总并发症发生率明显低于对照组，2组比较差异有统计学意义（P<0.05）；2组患者维持性血液透析不良反应发生率均较低，组间比较差异无统计学意义（P>0.05）。结论：金水宝片联合依诺肝素有助于改善维持性血液透析患者血脂代谢水平，降低维持性血液透析相关并发症，值得临床推广应用。     

The Relationship between College Graduate’s Dual Self-Consciousness and Job Search Clarity: The Mediating Role of Perceived Stress

The aim of the study was to explore the relationship between college graduates’ dual self-consciousness, job search clarity and perceived stress, and reveal the mediating role of perceived stress between dual self-consciousness and job search clarity. In this study, 467 college graduates were investigated using the Dual Self-Consciousness Scale, Job Search Clarity Scale, and Perceived Stress Scale. After controlling for gender, age, and region, the results revealed that: (1) private self-consciousness has a significant positive predictive effect on job search clarity; (2) perceived stress has a significant negative predictive effect on job search clarity; (3) perceived stress plays partial mediation effects between private self-consciousness and job search clarity; (4) perceived stress plays complete mediation effects between public self-consciousness and job search clarity; (5) perceived stress has suppressing effects between public self-consciousness and job search clarity.