Effects of radiation therapy on tumor microenvironment: an updated review / 中华医学杂志(英文版)

Cancer is a major threat to human health and causes death worldwide. Research on the role of radiotherapy (RT) in the treatment of cancer is progressing; however, RT not only causes fatal DNA damage to tumor cells, but also affects the interactions between tumor cells and different components of the tumor microenvironment (TME), including immune cells, fibroblasts, macrophages, extracellular matrix, and some soluble products. Some cancer cells can survive radiation and have shown strong resistance to radiation through interaction with the TME. Currently, the complex relationships between the tumor cells and cellular components that play major roles in various TMEs are poorly understood. This review explores the relationship between RT and cell-cell communication in the TME from the perspective of immunity and hypoxia and aims to identify new RT biomarkers and treatment methods in lung cancer to improve the current status of unstable RT effect and provide a theoretical basis for further lung cancer RT sensitization research in the future.

Correlation between dietary approaches to stop hypertension pattern and central obesity affected by PM2.5 exposure / 环境与职业医学

Background There is a lack of evidence on whether exposure to PM2.5 and its constituents would affect the relationship between the dietary approaches to stop hypertension (DASH) and central obesity. Objective To investigate the effect of exposure to PM2.5 and its constituents on the correlation between the DASH dietary pattern and the prevalence of central obesity. Methods The data were obtained from the baseline survey of the "Xinjiang Multi-Ethnic Natural Population Cohort Construction and Health Follow-Up Study" in Urumqi. A DASH score was calculated according to intake frequency of 8 food groups, and summed from intake frequency of recommended food groups scored from 1 to 5 from low to high, and intake frequency of restricted food groups scored from 1 to 5 from high to low. A higher DASH score indicates better compliance with the DASH dietary pattern. We estimated exposure using satellite-derived PM2.5 and a chemical transport model (GEOS-Chem) for its constituents, including organic carbon (OC), black carbon (BC), sulfate (SO42−), nitrate (NO3−), ammonium (NH4+), and soil dust. Central obesity was defined by waist circumference: ≥90 cm for men or ≥85 cm for women according to Criteria of weight for adults (WS/T 428—2013). A logistic regression model was used to analyze the effects of the DASH dietary pattern as well as PM2.5 and its constituents on central obesity, and a stratified analysis was used to explore the effects of PM2.5 and its constituents on the association between the DASH dietary pattern and central obesity. Results The study included 9 565 urban residents, aged (62.30±9.42) years, with a central obesity prevalence rate of 60.75%. After adjusting for selected confounders, the DASH score Q5 group had a 17.5% lower risk of central obesity than the Q1 group (OR=0.825, 95%CI: 0.720-0.947). PM2.5 and its constituents OC, BC, SO42−, NH4+, and soil dust were positively associated with the prevalence of central obesity, but no association was observed between constituent NO3− exposure and central obesity. The stratified analysis revealed that the prevalence of central obesity was reduced in the DASH score Q5 group in participants exposed to low concentrations of PM2.5 and its constituents NO3−, NH4+, and soil dust, while the protective effect of the DASH pattern on central obesity disappeared in subjects exposed to high concentrations of PM2.5 and its constituents NO3−, NH4+, and soil dust. Conclusion Exposure to PM2.5 and its constituents NO3−, NH4+, and soil dust could attenuate the protective effect of the DASH pattern on central obesity.

Mechanism of inhibition of platelet activation by tanshinone type ⅡA though G protein signal pathway / 国际检验医学杂志

Objective To discuss the mechanism of inhibition of platelet activation by tanshinone type ⅡA(TanⅡA) through G protein signal pathway.Methods Methylthiazolyldiphenyl-tetrazolium bromide(MTT) test was used to determine the optimum effective concentration and optimal time of thrombin and TanⅡA on platelet.Northern blot and Western blot were used to detect the transcription and expression levels of G protein and related signal molecules,including protease activated receptors(PARs),P2Y1 and P2Y12 receptors,α2A-adrenergic receptor and thromboxane A2(TXA2) receptor,in control group,thrombin treated group and TanⅡA treated group,and the platelet aggregation rate was also detected.Results Platelet aggregation rate,and the transcription and expression levels of G protein and related molecules in thrombin treated group were higher than control group(P<0.05).The transcription and expression levels of G protein and related molecules in different concentrations of TanⅡA treated groups were lower than thrombin treated group(P<0.05).Conclusion TanⅡA could inhibit the activation of platelet by inhibiting the transcription and expression of G protein and the related molecules.