The Mechanism Of Long Non-coding RNA LINC00460 Regulating Proliferation And Apoptosis Of Colorectal Cancer Cells

Background:Long noncoding RNAs(lncRNA)have been shown to involve in human cancer biology but their mechanisms of action are mainly undocumented.Current evidence suggested that IncRNA play a critical role in the regulation of tumor cellular processes,such as proliferation,apoptosis,and metastasis.Methods:By utilizing publicly available IncRNAs expression profiling data and other publicly available lncRNAs expression profiling data,we screened out LINC00460,whose expression is significantly increased in colorectal cancer(CRC).The quantitative reverse transcriptase PCR(qRT-PCR)was used to analyse the expression of LINC00460 in 60 CRC tissues and correspond adjacent normal tissues and four CRC cell lines.Gain and loss of function approaches were used to investigate the biological role of LINC00460 both in vitro and in vivo.Bioinformatics analysis followed by qRT-PCR were performed to identify the putative targets of LINC00460,which were further verified by RNA immunoprecipitation(RIP),Chromatin immunoprecipitation(ChIP),Luciferase reporter assays,rescue experiments and western blotting assays.Results:In this study,we analyzed of TCGA RNA sequencing data and other publicly available microarray data.We found that a novel IncRNA,LINC00460,which expression was significantly up-regulated in CRC tissues compared to adjacent normal tissues.Furthermore,qRT-PCR results verified that LINC00460 is over-expressed in CRC tissues and cells.In vitro and in vivo assays of LINC00460 alterations revealed a complex integrated phenotype affecting cell growth and apoptosis.Mechanistically,LINC00460 repressed underlying target gene KLF2 transcription through binding to EZH2.LINC00460 also functioned as a molecular sponge for miR-1297,antagonizing its ability to repress CUL4A protein translation.Conclusions:LINC00460 is significantly up-regulated in CRC tissues compared with adjacent normal tissues,suggesting that the ectopic expression of LINC00460 was related to the tumorigenesis of CRC.Mechanistic investigations showed that LINC00460 could exhibit different regulatory mechanisms in nucleus and cytoplasm,thus regulating KLF2 and CUL4A expression and affecting cell proliferation and apoptosis in CRC.Taken together,our findings support a model in which the LINC00460/EZH2/KLF2 and LINC00460/miR-149-5P/CUL4A crosstalk serve as critical effectors in CRC tumorigenesis and progression,suggesting new therapeutic directions in colorectal cancer.