Résumé
Objective:To investigate the correlations between expression of long noncoding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), nuclear-enriched abundant transcript 1 (NEAT1) and their functions on exosome secretion, proliferation and invasion in hepatocellular carcinoma (HCC).Methods:We used small interfering RNA of MALAT1 (si-MALAT1) to knockdown MALAT1 in HuH-7. At the meanwhile, cells which were transfected with si-NC were used as the negative control group. Expression of NEAT1, cell proliferation and invasion function were detected these two groups. HuH-7 cells were transfected with lentivirus NEAT1 over expressing vector (lv-NEAT1) or negative control (lv-control). Expression of exosomes secretion related genes were analyzed between lv-NEAT1 and lv-control groups. Cells of lv-NEAT1 were knockdown MALAT1 expression using si-MALAT1, which could be si-MALAT1+ lv-NEAT1 group. exosomes secretion was detected in si-NC, si-MALAT1 and si-MALAT1+ lv-NEAT1 group. We treated cells (si-MALAT1 group) with exosomes from cells with lv-NEAT1 or lv-control to divide cells as si-MALAT1+ exosomes of lv-NEAT1 cells and si-MALAT1+ exosomes of lv-control groups. Cell proliferation and invasion of cells were detected in two groups.Results:Low expression of NEAT1 were found in MALAT1 knockdown cells compared with si-NC group [(0.72±0.02) vs. (0.98±0.01), P<0.05]. Cells with MALAT1 knockdown shown diminished proliferation [(0.66±0.03) vs. (0.98±0.04), P<0.05)] and invasion [(88.33±7.26) vs. (147.70±13.62), P<0.05)]. Compared with si-NC group, CD9 and CD63 expression were decreased in exosomes of si-MALAT1 group. Compared with si-MALAT1 group, CD9 and CD63 expression was increased in exosomes of si-MALAT1+ lv-NEAT1 group. Compared with si-MALAT1+ exosomes of lv-control group, proliferation [(0.97±0.03) vs. (0.74±0.05), P<0.05)] and invasion [ (132.70±7.36) vs. (98.33±6.01), P<0.05) ] were increased in si-MALAT1+ exosomes of lv-NEAT1 group. Exosomes related genes expression including HSPA8 (5.53±0.31), SLC3A2 (0.32±0.07) and SLC7A5 (0.77±0.45) were changed in lv-NEAT1 group compared with lv-control group [(0.98±0.15), P<0.05]. Conclusion:MALAT1 induced exosomes secretion by NEAT1 and exosomes related genes regulation. This regulation might be related with increased proliferation and invasion function in HCC cells with MALAT1 and NEAT1 abnormal expression.