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.     

放射性心脏损伤动物模型相关实验研究进展

当利用放射线对胸部恶性肿瘤进行治疗时，位于纵隔的心脏会不可幸免受到照射，从而诱发放射性心脏损伤（radiation-induced heart disease, RIHD）。随着手术以及放化疗技术的提升，肿瘤患者生存时间得到延长，使得RIHD这一放疗远期并发症被越来越多的报道。因此，学者们对于RIHD的研究逐渐升温。目前国内外学者关于该疾病尚未形成统一的认识，临床上缺乏有效阻止其发生的方法。动物模型研究可为临床该疾病治疗及预防提供可靠证据，为此本文回顾分析近年来放射性心脏损伤动物模型实验研究情况，旨在为后续实验开展及临床应用提供参考。     

Determination of polycyclic aromatic hydrocarbons (PAHs) in cosmetic products by gas chromatography-tandem mass spectrometry

A gas chromatography coupled with tandem mass spectrometry (GC-MS/MS) method is developed to determine 18 representative polycyclic aromatic hydrocarbons (PAHs) in cosmetics, including Benzo[a]pyrene (BaP) and others. The method offers high sensitivity and selectivity under selected reaction monitoring (SRM) mode to satisfy the requirements of both quantitation and qualitation. The extraction solvent system used in this study is acetone/hexane 1:1 (v/v) and other purification procedure is unnecessary. The linearities of 18 PAHs are validated in different concentration in the range of 0.25–20 ng/mL individually with coefficient correlation (r) higher than 0.996. The recoveries for spiking 3 different concentrations are from 87.40% to 120.44% for 18 PAHs and the coefficient of variation (CV) are below 12.32%. Limit of quantification (LOQ) of 18 PAHs is in the range of 0.05–0.2 mg/kg. A matrix enhancement effect is observed and can be compensated with deuterated internal standard. The method has been successfully applied to 73 samples, over 40 of them are lipsticks. The results show none of the samples detect Benzo[a]pyrene (BaP) and Dibenzo[a,h]anthracene (DBA), both are classified as the most carcinogenic. 8 PAHs are detected and the average value between 0.08 and 0.27 mg/kg. This study offers a sensitive and simple method to analyze 18 representative PAHs successfully and can be applied to cosmetic products and raw materials.     

The prognostic role of tumour‐infiltrating lymphocytes in oral squamous cell carcinoma: A meta‐analysis

It has been suggested that tumour‐infiltrating lymphocytes (TILs) are associated with the progression of oral squamous cell carcinoma (OSCC). However, the prognostic value of TILs is inconclusive due to the heterogeneity of immune cells within the tumour microenvironment. In this meta‐analysis, we aimed to assess the prognostic value of TILs in OSCC. The PubMed, Cochrane, Embase, Scopus and Web of Science databases were searched up to April 20, 2019, and 33 studies were ultimately included in this meta‐analysis. Our pooled meta‐analysis showed that high infiltration of CD8⁺ TILs, CD45RO⁺ TILs and CD57⁺ TILs favoured better overall survival (OS). However, high infiltration of CD68⁺ macrophages and CD163⁺ macrophages was associated with poor prognosis in OSCC. These findings suggest that CD8⁺ TILs, CD45RO⁺ TILs, CD57⁺ TILs, CD68⁺ macrophages and CD163⁺ macrophages might serve as novel prognostic factors and therapeutic targets in OSCC.     

结直肠癌化疗患者营养状况及营养治疗研究进展

结直肠癌是常见的消化道肿瘤，其营养不良发生率高且严重。化疗是结直肠癌常见治疗方式之一，并与营养不良独立相关，化疗后患营养不良风险增大且营养不良进一步加重。同时，营养不良可导致患者化疗疗效差及预后不良，并增加化疗相关不良反应、影响患者生活质量及降低生存率等。营养治疗能够有效改善患者营养状况，在肿瘤综合治疗中有重要作用，且多学科团队合作是有效的营养干预模式。目前营养治疗主要包括营养咨询、口服营养补充剂、肠内营养和肠外营养等，相关指南和研究表明在营养治疗时应首选口服营养补充剂及肠内营养，仅在采用以上治疗后仍存在营养不足或无法进行肠内营养时行肠外营养。本文主要对结直肠癌患者营养状况与化疗之间关系、营养治疗的最新研究进展及相关指南进行综述，以期引起临床上对结直肠癌化疗患者营养治疗方面重视并提供参考。     

Research progress on accelerator-based stereotactic body radiotherapy

Stereotactic body radiotherapy (SBRT) has become an important radiotherapy technology. In recent years, with the continuous improvement of the mechanical properties of the linear accelerator (LINAC), LINAC-based SBRT is gradually emerging. In this article, the history, technological progress, radiation physics, clinical application of LINAC-based SBRT were elaborated, aiming to promote the development of LINAC-based SBRT.