Objective In this research ,the effects of exogenous C 2-ceramide on the induction of apop-tosis of mesothelioma cells in vitro and related important proteins are investigated .Mtehods Mesothelioma cells were treated with various doses of C 2-ceramide for different duration .Cell viability were analyzed by cell count-ing kit-8 assay.Morphological changes of apoptosis of mesothelioma cells were observed by Diff Quik staining . Apoptosis of mesothelioma cells was also detected by Caspase -3 assay and lactate dehydrogenase(LDH)assay. Related important proteins involved in the signal transduction of apoptosis were detected by western blot .Results In vitro,C2-ceramide demonstrated a dose -and time-dependent inhibition of cell proliferation .Apoptotic bodies were observed by Diff Quik staining .The antiproliferative effect of 80 μm C2-ceramide was paralleled with an increase in Caspase -3 activity.LDH assay showed that C2-ceramide at a concentration of 80μm signifi-cantly promoted cells death .After treated by C2-ceramide,the expressions of Bax and the phosphorylated JNK in mesothelioma cells were increased , however , the expression of phosphorylated ERK 1/2 kinase was decreased . Conclusion Our results indicate that C 2-ceramide induced apoptosis of malignant mesothelioma cells in vitro . This anti-tumor affect is achieved by adjusting related important proteins .

Objective To study the functions and mechanisms of glutamine 1 (GLS1) in intrahepatic cholangiocarcinoma (ICC) cell to 5-fluorouraeil (5-FU) chemosensitivity.Methods The expression and relation between GLS1 and major vault protein (MVP) in cholangiocarcinoma were analyzed by bioinformatics database.Western blot and immunohistochemistry were used to detect the expression of GLS1 and MVP in 42 ICC tissues,and the correlation between GLS1 and MVP was studied by statistics.The regulation of GLS1 in ICC cell were evaluated by siRNA interference and pcDNA overexpression,and then tested the interference and overexpression efficiency of GLS1 by Western blotting.The chemosensitivity to 5-Fu was tested by cell counting kit-8 (CCK-8).Results The expression of GLS1 and MVP in ICC tissues was significantly up-regulated (tGLSI =3.963;tMVP =3.131,P ＜ 0.05),and the expression of GLS1 was positively correlated with MVP(r2 =0.351 7,P ＜ 0.05).Knockdown of GLS1 in QBC939 cells enhanced chemosensitivity of QBC939 cells to 5-Fu and notably downregulated MVP expression,while enforced expression of GLS1 in RBE cells promoted MVP expression and reduce cell sensitivity to 5-fluorouracil chemosensitivity.Conclusions GLS1 regulates the chemosensitivity of ICC cells to 5-Fu,and its mechanism may relates to the regulation of MVP.