关键词: 食管鳞状细胞癌, miR-203a-3p, GATA6, 增殖, 侵袭

Abstract: Background and purpose: Bioinformatics analysis showed that GATA6 was a potential target gene for miR-203a-3p. This study aimed to determine whether miR-203a-3p could inhibit proliferation and invasion of esophageal squamous cell carcinoma (ESCC) cells by targeting GATA6. Methods: Transient transfection was performed with Lipofectamine ^TM RNAiMAX in cultured KYSE-70 and KYSE-180 cell lines. The expressions of miR-203a-3p and GATA6 were detected by real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR). GATA6 protein expression was detected by Western blot. The relative luciferase activity was further detected by dual-luciferase reporter assay after co-transfection with plasmid by FuGENE reagent. The expression levels of miR-203a-3p and GATA6 in esophageal malignant and dysplastic tissues were determined by RTFQ-PCR after microdissection of specimens. Results: The RTFQ-PCR and Western blot results showed that, compared with the control group, the expression levels of GATA6 mRNA and protein were significantly decreased in miR-203a-3p mimic transfection group, while significantly increased in the miR-203a-3p inhibitor transfection group (P<0.05). The expression levels of GATA6 and miR-203a-3p were inversely correlated. Compared with the control group, the cell proliferation viability in the KYSE-70 cell line was decreased in the miR-203a-3p mimic transfection group, while increased in the miR-203a-3p transfection group, which was statistically significant (P<0.05). Although it did not reach statistical significance in the KYSE-180 cell line, its trend was consistent with that of the KYSE-70 cell line. Compared with the control group, the relative number of invasive cell per field in the miR-203a-3p mimic transfection group decreased significantly (P<0.01), while increased in the miR-203a-3p inhibitor transfection group (P<0.05), which had significant statistical significance. Compared with miR-203a-3p scrambled + GATA6 wild type group and miR-203a-3p wild type +GATA6 mutant group, relative luciferase enzyme activity in miR-203a-3p wild type+GATA6 in wild type group significantly decreased (P<0.05). Compared with the dysplastic tissues, the miR-203a-3p expression in esophageal malignant tissues decreased in all the ESCC patients, while GATA6 expression level increased. Conclusion: miR-203a-3p could inhibit the proliferation and invasion ability of ESCC by targeting GATA6.

Key words: Esophageal squamous cell carcinoma, miR-203a-3p, GATA6, Proliferation, Invasion