| Background and objective:The incidence of gastric cancer ranks sixth among malignant tumors in the world,and its mortality ranks third,which is one of the main causes of death of cancer patients.Early gastric cancer usually lacks specific symptoms.At this stage,80%of patients in China are found to be in the advanced stage of gastric cancer.LncRNA is a powerful non-coding RNA that can regulate a variety of tumors,including gastric cancer.Recent studies have shown that LINC01342 is highly expressed in ovarian cancer and is related to the prognosis of patients with ovarian cancer.However,the expression and mechanism of LINC01342 in gastric cancer are not clear.The purpose of this study is to study the expression of LINC01342 in tissue and plasma of patients with gastric cancer and its correlation with GC,to explore the effect of LINC01342 on biological behavior of gastric cancer cells through cell experiments,and to explore the potential mechanism of LINC01342 in gastric carcinogenesis through follow-up experiment.It would be helpful for clinical diagnosis,treatment and follow-up research of gastric cancer.Methods1.LINC01342 was screened out by bioinformatics analysis.2.RT-qPCR was used to detect the expression of LINC01342 in 70 gastric cancer tissues and corresponding paracancerous tissues,and the correlation between the expression of LINC01342 and clinical data was analyzed.Survival curve was drawn to analyze the correlation between the expression of LINC01342 and overall survival.The expression of LINC01342 in plasma of 22 patients with gastric cancer and 22 healthy subjects collected in the same period was detected.ROC curve was drawn to evaluate the diagnostic value of LINC01342 in gastric cancer.3.RNA interference test was used to knock down LINC01342 and then detected the knockdown efficiency.It was used to study the effects of knocking down LINC01342 on the proliferation,migration,invasion and apoptosis of gastric cancer cells.4.RT-qPCR,Western blot and other methods were used to find and clarify the potential downstream mechanism of LINC01342.The effect of LINC01342 knocked down on EMT phenotype of gastric cancer cells was observed by cell morphology experiment.RT-qPCR and Western blot were used to verify the expression of EMT gene and protein during malignant transformation of gastric cancer.Results:1.RT-qPCR results showed that the expression level of LINC01342 in gastric cancer was significantly higher than that in adjacent tissues.The expression of LINC01342 was positively correlated with TNM stage,lymph node metastasis,tumor differentiation and adjacent tissue invasion in patients with gastric cancer.The survival curve showed that the overall survival of patients with high expression of LINC01342 was worse than that of patients with low expression of LINC01342.The area under the curve of ROC for screening gastric cancer with plasma LINC01342 was 0.715(95%CI:0.559～0.87),suggesting that LINC01342 has potential value in clinical diagnosis of gastric cancer.2.The results of RNA interference experiments showed that the knockdown efficiency of the designed LINC01342 oligonucleotides was satisfactory.LINC01342 Knocked down significantly inhibited the proliferation,migration and invasion of AGS and HGC-27,and increased the level of apoptosis.3.RT-qPCR results showed that LINC01342 knockdown significantly affected the TWISTregulated EMT process,such as decreased expression of TWIST,FN1,MMP9,N-cad and increased expression of E-cad,but there was no significant change on classical molecules such as SNAIL and SLUG.The Western blot experiment also supported the above results.4.Cell morphology experiments showed that LINC01342 knockdown in AGS and HGC-27 caused cell morphology change from spindle-like morphology to pebble-like morphology,suggesting that LINC01342 knockdown could weaken the EMT morphology of gastric cancer cells.5.The results of RT-qPCR and Western blot also showed that the expression of TWIST,FN1,MMP9 and N-cad increased while the expression of E-cad decreased in the group with high expression of LINC01342,suggesting that there is a correlation between the expression of LINC01342 in gastric cancer and the TWIST-regulated EMT process.Conclusion:The expression of LINC01342 in gastric cancer tissue and plasma is significantly increased,and the expression of LINC01342 is closely related to TNM stage,lymph node metastasis,tumor differentiation,adjacent tissue invasion and overall survival in patients with gastric cancer,LINC01342 may affect a variety of malignant phenotypes of gastric cancer through TWISTregulated EMT pathway,and finally promote the occurrence and development of gastric cancer... |
PDF Full Text Request