METTL16 Inhibits the Malignant Progression of Epithelial Ovarian Cancer through the lncRNA MALAT1/β-Catenin Axis

Figure 4

Expression level of lncRNA MALAT1 is downregulated by METTL16 in EOC cells. (a) The downstream target of METTL16, lncRNA MALAT1, was selected from the common seven genes identified from the five GEO datasets indicated. (b) The mRNA expression level of lncRNA MALAT1 was observed by RT-qPCR in adjacent noncancerous tissues (n = 30) and EOC tissues (n = 30). (c) The correlation between lncRNA MALAT1 and METTL16 expression levels in 30 EOC tissues was observed by RT-qPCR. r = −0.43, by Spearman correlation analysis. (d) Expression level of lncRNA MALAT1 in SKOV3 and OVCAR3 cells detected by RT-qPCR. (e) Relative mRNA expression level of MALAT1 72 hr after SKOV3 and OVCAR3 cells were transfected with si-MALAT1 (si-MALAT1-1 or si-MALAT1-2). (f) EdU assay was conducted to assess the proliferation ability of SKOV3 and OVCAR3 cells subsequent to the downregulation of lncRNA MALAT1 expression using si-MALAT1 (si-MALAT1-1 or si-MALAT1-2). Furthermore, the proliferation ability of SKOV3 cells was evaluated using the EdU assay following the knockdown of METTL16 alone, as well as the combined knockdown of METTL16 and lncRNA MALAT1 (scale bar, 100 μm). (g) LncRNA MALAT1 expression level detected by RT-qPCR in SKOV3 and OVCAR3 cells with METTL16 stable knockdown by sh-METTL16-1. (h) RIP assay was performed in SKOV3 and OVCAR3 cells, followed by RT-qPCR to detect enrichment of lncRNA MALAT1. (i) RT-qPCR analysis of lncRNA MALAT1 in METTL16-transfected SKOV3 and OVCAR3 cells treated with actinomycin D (5 μg/mL) for 0, 2, 4, 6, or 8 hr. ns: , , , and . EdU, 5-ethynyl-2′-deoxyuridine; RIP, RNA immunoprecipitation.

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