Research The Expression And Function Of The Long Chain Noncoding RNA RP11-783K16.13 In Gastric Adenocarcinoma

Purpose:Based on the previous results from the chip assay,we choose the abnormally expressed Lnc RNA RP11-783K16.13 for this study,to explore its expression level in gastric adenocarcinoma tissues and the relationship between its expression and the clinicopathological characteristics of patients with gastric adenocarcinoma(GA).We also studies the changes in the level of the expression of Lnc RNA RP11-783K16.13 on affecting the function of GA cells.Finally,predicting and verifying the target genes of Lnc RNA RP11-783K16.13.Methods:(1)Based on the previous results from the Lnc RNA microarray chip assay,we screened out a larger more than 2 fold changes in the expression levels and the no literature reported Lnc RNA: Lnc RNA RP11-783K16.13 for this study.Its expression levels in GA tissues and matched non-cancerous tissues were detected by real-time fluorescent quantitative PCR(q RT-PCR)technology,and the correlations between its expression level and clinical data were then analyzed.(2)To explore the down-reglution of the expression of Lnc RNA RP11-783K16.13 on the affecting of GA cells,first using si RNA interference technology to inhibit the expression of Lnc RNA RP11-783k16.13 in BGC-823 and SGC-7901 cells,then through a series of assays including the clone formation experiment for cell growth,CCK8 assay for cell proliferation,transwell for cell migration and invasion,and flow cytometry analysis for cell apoptosis.(3)Using bioinformatics technology to predict lnc RNA RP11-783K16.13 associated gene and downstream target genes,and q RT-PCR to analyze the correlation between the expression levels of lnc RNA RP11-783K16.13 and its associated gene(protein phosphatase 1 regulatory subunit 14 B,PPP1R14B).Results:(1)The previous results from the lnc RNA expression chip assay showed that Lnc RNA RP11-783k16.13 was over-expressed in GA tissues,compared with that in para-carcinoma,its average over-expressed fold was 5.23.The q RT-PCR verified results showed that ln RNA RP11-783K16.13 was over-expressed in 68 out of 100 GA tissues,compared with that in para-carcinoma tissuses(p<0.05),and over-expressed rate of Lnc RNA RP11-783K16.13 in GA tissues was 68%.Further analysis showed that its expression was related to clinical pathological data of TNM staging,lymph node metastasis,vascular invasion and the immunohistochemical marker thymidylate synthase(TS)(p<0.05),but not associated with the patient’s age,gender,the degree of differentiation,tumor size and tumor location(p>0.05).(2)The expression of Lnc RNA RP11-783K16.13 was also increased in 4 different GA cells(MGC-803,BGC-823,SGC-7901 and AGS cells),compared with that in normal gastric mucosa epithelial cell GES-1(p<0.05).Transfecting Lnc RNA RP11-783k16.13 si RNAs into BGC-823 and SGC-7901 cells and down-regulating the expression of Lnc RNA RP11-783K16.13 in these two GA cells,leading to decreased proliferation,growth,migration and invasion in GA cells(p<0.05),but no statistically significant affecting on apoptosis in SGC-7901 GA cells(p>0.05).(3)The expression of Lnc RNA RP11-783K16.13 associated gene PPP1R14 B was also over-expressed in GA tissues,compared with that in the para-carcinoma tissuses(p<0.05),and over-expression rate of PPP1R14 B was 59%,which was positively correlated with the expression of Lnc RNA RP11-783K16.13 with a correlation coefficient of R=0.813(p<0.01).Inhibiting the expression of Lnc RNA RP11-783K16.13 in BGC-823 and SGC-7901 cells by si RNAs,also leading to decreased PPP1R14 B expression in these two GA cells.The downstream target genes predicted results show that there are 21 m RNA may be lnc RNA RP11-783k16.13 target genes.Conclusions: Lnc RNA RP11-783K16.13 was over-expressed in both GA tissues and cell lines,which was related with TNM staging,lymph node metastasis,vascular invasion and the levels of tissue immunohistochemical marker TS.Inhibiting the expression of Lnc RNA RP11-783k16.13 in GA cells,leading to decreased the proliferation,migration,and invasion in GA cells.The functions of Lnc RNA RP11-783k16.13 in GA cells in GA cells may be related with its regulation of the expression of PPP1R14 B.The data of this study preliminarily showed that lnc RNA RP11-783K16.13 may be associated with GA development and progression,and could serve as a potential biomarker and treatment target for GA.