The Changes Of Expression And Clinical Significance Of LINC00978 In Colorectal Cancer

Background and objective:Long-chain non-coding RNAs(long noncoding RNA,lnc RNA)are widely involved in multiple processes of colorectal cancer development and progression.LINC00978 has been shown to be abnormally elevated in a variety of human tumors and plays a role in promoting cancer,but its mechanism of action in colorectal cancer has not been reported.The aim of this study was to detect the expression level of LINC00978 in tissues,serum of colorectal cancer patients,analyze the correlation between the expression level and clinical data and study its relationship in colorectal cancer cells.Finally,we aim to provide new biomarkers and ideas for the diagnosis and treatment of colorectal cancer.Materials and methods:1.Real-time quantitative PCR(qRT-PCR)was used to detect the expression level of LINC00978 in tumor tissues and serum of colorectal cancer patients.The correlation between the expression level of LINC00978 and clinical pathological data(such as gender,age,tumor size,degree of differentiation,degree of infiltration,Lymph node metastasis and TNM staging,etc)was analyzed to explore and evaluate its potential value as a new biomarker for colorectal cancer.2.Colorectal cancer cells SW480 and HCT-8 were transfected with shRNA and overexpression plasmid.The cell proliferation was detected by growth curve and colony formation assay.Apoptosis was detected by flow cytometry.QRT-PCR and western blot were used to detect the changes of cell proliferation-related genes and protein expression.3.Transwell migration and invasion assays were used to detect changes in cell migration and invasion.We use qRT-PCR and Western blot to observe the changes of cell epithelial-mesenchymal transition(EMT)-related genes and protein expression,analyze the activation changesd of the related signaling pathways.Result:1.The results of qRT-PCR showed that the expression of LINC00978 was significantly higher in the tumor tissues and serum and colorectal cancer cells of colorectal cancer patients than in the normal control group.Correlation analysis showed that the expression level of LINC00978 in colorectal cancer was significantly correlated with tumor size,differentiation and lymph node metastasis in cancer patients(P<0.05).2.After the interferenc of sh RNA in colorectal cancer cells SW480 and HCT-8,the expression level of LINC00978 was significantly decreased,the cell cycle was inhibited and apoptosis was induced obviously.Also the cell proliferation ability was significantly reduced.While overexpression of LINC00978 can promote cell cycle progression,inhibit apoptosis,and enhance the cell proliferation.3.After LINC00978 knockdown,the migration and invasion ability of colorectal cancer cells was significantly weaker than the control group.The results of qRT-PCR and Western blot showed that the TGF-?/SMAD-related signaling pathway was inhibited in colorectal cancer cells after knockdown of LINC00978.And the results of overexpression group was reversed,which suggesting that the epithelial-mesenchymal transition of colorectal cancer cells was inhibited.Conclusions:LINC00978 is highly expressed in tumor tissues and serum of colorectal cancer patients,and the expression level is significantly correlated with tumor size,differentiation degree and lymph node metastasis in patients with colorectal cancer(P<0.05).LINC00978 can promote cell apoptosis and epithelial-mesenchymal transition(EMT)of colorectal cancer cells through TGF-?/SMAD signaling pathway,thereby acting as a proto-oncogene in the development of colorectal cancer.Combined with the above factors,LINC00978 is expected to become a new biological molecular marker for the diagnosis and treatment of colorectal cancer.