LINC00511 promotes gastric cancer cell growth by acting as a ceRNA

Figure 1 LINC00511 expression is upregulated and promotes gastric cancer cell growth. A: Quantitative real-time PCR, analysis was performed to detect the expression of LINC00511 in normal gastric cells and gastric cancer (GC) cells; B: Quantitative real-time PCR, analysis was conducted to examine the knockdown efficiency of si-LINC00511#1/2/3; C, D: CCK-8 and colony formation assays were used to measured cell proliferation after the knockdown of LINC00511 in GC cells; E: A cell apoptosis-related protein (Caspase 3) was assessed by WB assay. ^aP < 0.05, ^bP< 0.01.

Figure 2 MiR-124-3p is downregulated in gastric cancer and inhibits cell growth. A: The relative expression of miR-124-3p in normal gastric cells and gastric cancer (GC) cells was analyzed by quantitative real-time PCR; B: The overexpression efficiency of miR-124-3p mimics was measured with quantitative real-time PCR; C, D: The effect of miR-124-3p overexpression on cell proliferation in GC cells was investigated by CCK-8 and colony formation assays; E: WB assay was used to examine the protein levels of cleaved caspase-3 and total caspase-3. ^aP < 0.05, ^bP < 0.01.

Figure 3 MiR-124-3p can bind LINC00511. A: The potential binding site between miR-124-3p and LINC00511 was predicted by the starBase v2.0 software; B: Quantitative real-time PCR was used to assess the expression level of miR-124-3p after the knockdown of LINC00511; C, D: RIP and luciferase reporter assays were used to confirm the interaction between miR-124-3p and LINC00511; E: The RNA pull-down assay suggested the direct interaction of miR-124-3p and LINC00511. ^aP < 0.05, ^bP < 0.01.

Figure 4 PDK4 is a downstream target of miR-124-3p. A: The expression level of PDK4 in gastric cancer (GC) cells and normal gastric cells was determined by quantitative real-time PCR; B, C: Quantitative real-time PCR and WB assays were utilized to examine the expression level of PDK4 after miR-124-3p overexpression; D: The binding site of miR-124-3p and PDK4 was predicted with starBase v2.0; E: A luciferase reporter assay was used to verify that miR-124-3p could sponge PDK4; F: WB assay showed that LINC00511 silencing resulted in a reduction of PDK4 protein levels, which was partly rescued by miR-124-3p inhibition. ^aP < 0.05, ^bP < 0.01.

Figure 5 LINC00511 promotes gastric cancer cell growth by regulating PDK4 expression. A: Quantitative real-time PCR was employed to explore the mRNA levels of PDK4 in GC cells transfected with pcDNA3.1/PDK4; B, C: Cell proliferation ability was examined by CCK-8 and colony formation assays; D: WB assay was used to examine the protein level of cleaved caspase-3 and total caspase-3. ^aP < 0.05, ^bP < 0.01.