Activation Of The Clock Gene TIMELESS By H3k27 Acetylation Promotes Colorectal Cancer Progress By Binding To Myosin-9

Colorectal cancer(CRC)is a common tumor characterized by its high mortality rate.However,the underlying molecular mechanisms that drive CRC tumorigenesis are unclear.Clock genes have important roles in tumor development.TIMELESS is a clock gene,which encodes the Timeless protein.Timeless was reported to be up-regulated in various types of cancer and to be involved in cancer development,progression,and poor patient survival.In the present study,the expression of the clock gene Timeless,was upregulated in CRC tissues compared with corresponding normal tissues as assessed by immunohistochemistry.Timeless expression was closely associated with the TNM stages and poor overall survival of CRC patients.It suggested that timeless protein may have important roles in the development of colorectal cancer.Functional studies demonstrated that Timeless promoted CRC cell proliferation,invasion,and EMT in vitro.Studies in vivo also suggested that Timeless could promote the proliferation and metastasis of CRC cell.In conclusion,Timeless could promote CRC cell proliferation,invasion,and EMT in vitro and in vivo.Given that Timeless participates in molecular regulation pathways by binding to proteins,we performed immunoprecipitation and mass spectrometry analysis experiments.The results suggested that Timeless could bind to Myosin-9 and affect Myosin-9 protein stability.Mechanistic investigations showed that Timeless activated the β-catenin signal pathway by binding to Myosin-9,which binds to β-catenin to induce its nuclear translocation.The upregulation of Timeless was attributed to acetyltransferase(P300)/CREB-binding protein(CBP)-mediated H3k27 acetylation of the promoter region of Timeless proving by Chromatin immunoprecipitation(Ch IP).Our results show that Timeless regulates tumorigenesis of CRC by binding and regulating Myosin-9 suggesting Timeless might be a potential prognostic biomarker and therapeutic target for CRC.