Objectives:Epigenetic changes,particularly N6-methyladenosine(m6A)modifications,play a pivotal role in cancer development.This study explored the role of ovarian tumor deubiquitinase 7B(OTUD7B)in esophageal squamous c...Objectives:Epigenetic changes,particularly N6-methyladenosine(m6A)modifications,play a pivotal role in cancer development.This study explored the role of ovarian tumor deubiquitinase 7B(OTUD7B)in esophageal squamous cell carcinoma(ESCC)in the context of m6A methylation and the hypoxia-inducible factor-1α(HIF-1α)pathway.Methods:The GSE179267 dataset was used to conduct differential gene expression analysis to identify key m6A-enriched genes.The Cancer Genome Atlas(TCGA),Cancer Cell Line Encyclopedia(CCLE),and Sequence-based RNA Adenosine Methylation Site Predictor(SRAMP)databases were used to evaluate the expression of OTUD7B in ESCC and its correlation with methyltransferase-like 14(METTL14)and HIF-1α.The m6A content in total RNA extracted from ESCC cells was assessed using a dot blot assay.Gene-specific m6A-PCR was used to quantify m6A modifications in OTUD7B mRNA.The functional role of OTUD7B was explored using clonogenic and Transwell assays.The effect of OTUD7B on HIF-1αubiquitination was detected using a co-immunoprecipitation assay.Results:OTUD7B was identified as a pivotal m6A-driven oncogene correlated with METTL14 and HIF-1α.METTL14 enhanced the mRNA stability and expression of OTUD7B through m6A methylation.OTUD7B overexpression counteracted the inhibitory effects of METTL14 knockdown on cell proliferation and invasion and stabilized HIF-1αby promoting deubiquitination.Conclusion:METTL14 plays a crucial role in the stabilization of OTUD7B through m6A methylation,thereby inhibiting the ubiquitin-proteasomal degradation of HIF-1αin ESCC.These findings highlight the potential of targeting the METTL14-OTUD7B axis as a therapeutic strategy for ESCC.展开更多
Background:Expression of mRNA is widely regulated by N6-methyladenosine(m6A).An increasing number of studies have shown that m6A methylation,facilitated by methyltransferase 3(METTL3),is crucial in the progression of ...Background:Expression of mRNA is widely regulated by N6-methyladenosine(m6A).An increasing number of studies have shown that m6A methylation,facilitated by methyltransferase 3(METTL3),is crucial in the progression of tumors.Previous reports have indicated the involvement of both METTL3 and c-Src kinase in the evolution of liver cancer.However,the potential connection between c-Src and the METTL3-mediated mechanism in liver cancer progression remains elusive.Methods:The correlation expression between c-Src and METTL3 between liver cancer patients and the control group was analyzed using the TCGA database,and was further demonstrated by Western blot and RT-qPCR.The functional roles of c-Src in METTL3-regulated liver cancer progression were investigated by cell proliferation assays and colony formation assays.The regulatory mechanism of METTL3 in c-Src expression was accessed by RNA-immunoprecipitation(RIP)-qPCR.Results:We demonstrated that c-Src kinase promoted liver cancer development,and the expression of SRC(encodes c-Src kinase)was positively correlated with METTL3 in liver cancer cases.We showed that SRC mRNA could be m6A-modified,and METTL3 regulated the transcription of SRC mRNA through interferon regulatory factor 1(IRF1).We revealed that IRF1,the expression of which was positively regulated byMETTL3,was a novel transcription factor of c-Src.Lastly,The pro-proliferative effect of METTL3 on hepatocellular carcinoma was mechanistically linked to IRF1/c-Src axis activation,as evidenced by our experimental data.Conclusion:Results suggested that the METTL3/IRF1/c-Src axis played potential oncogenic roles in liver cancer development and the axis may be a promising therapeutic target in the disease.展开更多
基金funded by the Doctoral Research Start-up Fund Project at Changzhi Medical College(grant number BS202118)Sichuan Science and Technology Program(grant number 2022YFS0631)Scientific and Technological Innovation Programs ofHigher Education Institutions in Shanxi(grant number 2021L348).
文摘Objectives:Epigenetic changes,particularly N6-methyladenosine(m6A)modifications,play a pivotal role in cancer development.This study explored the role of ovarian tumor deubiquitinase 7B(OTUD7B)in esophageal squamous cell carcinoma(ESCC)in the context of m6A methylation and the hypoxia-inducible factor-1α(HIF-1α)pathway.Methods:The GSE179267 dataset was used to conduct differential gene expression analysis to identify key m6A-enriched genes.The Cancer Genome Atlas(TCGA),Cancer Cell Line Encyclopedia(CCLE),and Sequence-based RNA Adenosine Methylation Site Predictor(SRAMP)databases were used to evaluate the expression of OTUD7B in ESCC and its correlation with methyltransferase-like 14(METTL14)and HIF-1α.The m6A content in total RNA extracted from ESCC cells was assessed using a dot blot assay.Gene-specific m6A-PCR was used to quantify m6A modifications in OTUD7B mRNA.The functional role of OTUD7B was explored using clonogenic and Transwell assays.The effect of OTUD7B on HIF-1αubiquitination was detected using a co-immunoprecipitation assay.Results:OTUD7B was identified as a pivotal m6A-driven oncogene correlated with METTL14 and HIF-1α.METTL14 enhanced the mRNA stability and expression of OTUD7B through m6A methylation.OTUD7B overexpression counteracted the inhibitory effects of METTL14 knockdown on cell proliferation and invasion and stabilized HIF-1αby promoting deubiquitination.Conclusion:METTL14 plays a crucial role in the stabilization of OTUD7B through m6A methylation,thereby inhibiting the ubiquitin-proteasomal degradation of HIF-1αin ESCC.These findings highlight the potential of targeting the METTL14-OTUD7B axis as a therapeutic strategy for ESCC.
基金supported by Natural Science Foundation of Hunan Province of China(project No.2022JJ40413)Outstanding Youth Project of Hunan Provincial Department of Education(project No.22B0814)+1 种基金Regional Consolidated Foundation ofHunan Province of China(project No.2023JJ50065)Natural Science Foundation of Hunan Province of China(project No.2023JJ50412).
文摘Background:Expression of mRNA is widely regulated by N6-methyladenosine(m6A).An increasing number of studies have shown that m6A methylation,facilitated by methyltransferase 3(METTL3),is crucial in the progression of tumors.Previous reports have indicated the involvement of both METTL3 and c-Src kinase in the evolution of liver cancer.However,the potential connection between c-Src and the METTL3-mediated mechanism in liver cancer progression remains elusive.Methods:The correlation expression between c-Src and METTL3 between liver cancer patients and the control group was analyzed using the TCGA database,and was further demonstrated by Western blot and RT-qPCR.The functional roles of c-Src in METTL3-regulated liver cancer progression were investigated by cell proliferation assays and colony formation assays.The regulatory mechanism of METTL3 in c-Src expression was accessed by RNA-immunoprecipitation(RIP)-qPCR.Results:We demonstrated that c-Src kinase promoted liver cancer development,and the expression of SRC(encodes c-Src kinase)was positively correlated with METTL3 in liver cancer cases.We showed that SRC mRNA could be m6A-modified,and METTL3 regulated the transcription of SRC mRNA through interferon regulatory factor 1(IRF1).We revealed that IRF1,the expression of which was positively regulated byMETTL3,was a novel transcription factor of c-Src.Lastly,The pro-proliferative effect of METTL3 on hepatocellular carcinoma was mechanistically linked to IRF1/c-Src axis activation,as evidenced by our experimental data.Conclusion:Results suggested that the METTL3/IRF1/c-Src axis played potential oncogenic roles in liver cancer development and the axis may be a promising therapeutic target in the disease.
