Objective Hepatocellular carcinoma(HCC)is the third leading cause of cancer-associated death worldwide.As a first-line drug for advanced HCC treatment,lenvatinib faces a significant hurdle due to the development of bo...Objective Hepatocellular carcinoma(HCC)is the third leading cause of cancer-associated death worldwide.As a first-line drug for advanced HCC treatment,lenvatinib faces a significant hurdle due to the development of both intrinsic and acquired resistance among patients,and the underlying mechanism remains largely unknown.The present study aims to identify the pivotal gene responsible for lenvatinib resistance in HCC,explore the potential molecular mechanism,and propose combinatorial therapeutic targets for HCC management.Methods Cell viability and colony formation assays were conducted to evaluate the sensitivity of cells to lenvatinib and dicoumarol.RNA-Seq was used to determine the differences in transcriptome between parental cells and lenvatinib-resistant(LR)cells.The upregulated genes were analyzed by GO and KEGG analyses.Then,qPCR and Western blotting were employed to determine the relative gene expression levels.Afterwards,the intracellular reactive oxygen species(ROS)and apoptosis were detected by flow cytometry.Results PLC-LR and Hep3B-LR were established.There was a total of 116 significantly upregulated genes common to both LR cell lines.The GO and KEGG analyses indicated that these genes were involved in oxidoreductase and dehydrogenase activities,and reactive oxygen species pathways.Notably,NAD(P)H:quinone oxidoreductase 1(NQO1)was highly expressed in LR cells,and was involved in the lenvatinib resistance.The high expression of NQO1 decreased the production of ROS induced by lenvatinib,and subsequently suppressed the apoptosis.The combination of lenvatinib and NQO1 inhibitor,dicoumarol,reversed the resistance of LR cells.Conclusion The high NQO1 expression in HCC cells impedes the lenvatinib-induced apoptosis by regulating the ROS levels,thereby promoting lenvatinib resistance in HCC cells.展开更多
Introduction:Oncogenic aaivation of the K-ras gene occurs in >90%of pancreatic ductal carcinoma and plays a critical role in the pathogenesis of this malignancy.Increase of reactive oxygen species(ROS) has also bee...Introduction:Oncogenic aaivation of the K-ras gene occurs in >90%of pancreatic ductal carcinoma and plays a critical role in the pathogenesis of this malignancy.Increase of reactive oxygen species(ROS) has also been observed in a wide spectrum of cancers.This study aimed to investigate the mechanistic association between K-ras-induced transformation and increased ROS stress and its therapeutic implications in pancreatic cancer.Methods:ROS level,NADPH oxidase(NOX) aaivity and expression,and cell invasion were examined in human pancreatic dua epithelial E6E7 cells transfeaed with K-ras^(G12V) compared with parental E6E7 cells.The cytotoxic effea and antitumor effect of capsaicin,a NOX inhibitor,were also tested in vitro and in vivo.Results:K-ras transfeaion caused activation of the membrane-associated redox enzyme NOX and elevated ROS generation through the phosphatidylinositol 3'-kinase(PI3K) pathway.Importantly,capsaicin preferentially inhibited the enzyme aaivity of NOX and induced severe ROS accumulation in K-ras-transformed cells compared with parental E6E7 cells.Furthermore,capsaicin effeaively inhibited cell proliferation,prevented invasiveness of /(-ras-transformed pancreatic cancer cells,and caused minimum toxicity to parental E6E7 cells.In vivo,capsaicin exhibited antitumor aaivity against pancreatic cancer and showed oxidative damage to the xenograft tumor cells.Conclusions:K-ras oncogenic signaling causes increased ROS stress through NOX,and abnormal ROS stress can selectively kill tumor cells by using NOX inhibitors.Our study provides a basis for developing a novel therapeutic strategy to effectively kill K-ras-transformed cells through a redox-mediated mechanism.展开更多
基金supported by the Global Select Project(No.DJK-LX-2022001)of the Institute of Health and Medicine,Hefei Comprehensive National Science Center.
文摘Objective Hepatocellular carcinoma(HCC)is the third leading cause of cancer-associated death worldwide.As a first-line drug for advanced HCC treatment,lenvatinib faces a significant hurdle due to the development of both intrinsic and acquired resistance among patients,and the underlying mechanism remains largely unknown.The present study aims to identify the pivotal gene responsible for lenvatinib resistance in HCC,explore the potential molecular mechanism,and propose combinatorial therapeutic targets for HCC management.Methods Cell viability and colony formation assays were conducted to evaluate the sensitivity of cells to lenvatinib and dicoumarol.RNA-Seq was used to determine the differences in transcriptome between parental cells and lenvatinib-resistant(LR)cells.The upregulated genes were analyzed by GO and KEGG analyses.Then,qPCR and Western blotting were employed to determine the relative gene expression levels.Afterwards,the intracellular reactive oxygen species(ROS)and apoptosis were detected by flow cytometry.Results PLC-LR and Hep3B-LR were established.There was a total of 116 significantly upregulated genes common to both LR cell lines.The GO and KEGG analyses indicated that these genes were involved in oxidoreductase and dehydrogenase activities,and reactive oxygen species pathways.Notably,NAD(P)H:quinone oxidoreductase 1(NQO1)was highly expressed in LR cells,and was involved in the lenvatinib resistance.The high expression of NQO1 decreased the production of ROS induced by lenvatinib,and subsequently suppressed the apoptosis.The combination of lenvatinib and NQO1 inhibitor,dicoumarol,reversed the resistance of LR cells.Conclusion The high NQO1 expression in HCC cells impedes the lenvatinib-induced apoptosis by regulating the ROS levels,thereby promoting lenvatinib resistance in HCC cells.
基金supported by research grants from the National Natural Science Foundation of China(No.81101520)the National Basic Research Program of China(973 program)(No.2013CB910304 and 2012CB967004)
文摘Introduction:Oncogenic aaivation of the K-ras gene occurs in >90%of pancreatic ductal carcinoma and plays a critical role in the pathogenesis of this malignancy.Increase of reactive oxygen species(ROS) has also been observed in a wide spectrum of cancers.This study aimed to investigate the mechanistic association between K-ras-induced transformation and increased ROS stress and its therapeutic implications in pancreatic cancer.Methods:ROS level,NADPH oxidase(NOX) aaivity and expression,and cell invasion were examined in human pancreatic dua epithelial E6E7 cells transfeaed with K-ras^(G12V) compared with parental E6E7 cells.The cytotoxic effea and antitumor effect of capsaicin,a NOX inhibitor,were also tested in vitro and in vivo.Results:K-ras transfeaion caused activation of the membrane-associated redox enzyme NOX and elevated ROS generation through the phosphatidylinositol 3'-kinase(PI3K) pathway.Importantly,capsaicin preferentially inhibited the enzyme aaivity of NOX and induced severe ROS accumulation in K-ras-transformed cells compared with parental E6E7 cells.Furthermore,capsaicin effeaively inhibited cell proliferation,prevented invasiveness of /(-ras-transformed pancreatic cancer cells,and caused minimum toxicity to parental E6E7 cells.In vivo,capsaicin exhibited antitumor aaivity against pancreatic cancer and showed oxidative damage to the xenograft tumor cells.Conclusions:K-ras oncogenic signaling causes increased ROS stress through NOX,and abnormal ROS stress can selectively kill tumor cells by using NOX inhibitors.Our study provides a basis for developing a novel therapeutic strategy to effectively kill K-ras-transformed cells through a redox-mediated mechanism.