Fig 2: Molecular function analysis of SGK2. (A). Molecular function analysis suggested that positive related genes of SGK2 were mainly enriched in receptor activity, ATP binding, DNA repair protein, transmembrane receptor activity and lipid binding. (B). Biological process analysis indicated SGK2 positive related genes were enriched in immune response, regulation of immune response, protein folding, signal complex formation and regulation of gene expression epigenetic. (C). Biological pathway analysis indicated SGK2 positive related genes were enriched in Mitotic M-M/G1 phases, G1/S Transition, Cell cycle mitotic, HIV infection, Cross-presentation of soluble exogenous antigens.

Fig 3: SGK2 regulates c-Myc/ß-catenin gene expression. (A). WB results showed the protein levels of ß-catenin and c-Myc were significantly decreased after down-regulating SGK2 expression in UMUC3 and J82 cells. (B). WB results showed the protein levels of ß-catenin and c-Myc were significantly increased after overexpressing SGK2 in T24 cell. (C). Immunoprecipitation (IP) assay indicated SGK2 could directly interact with ß-catenin protein in T24 cell. (D). MG132 (10 µM) abrogated shSGK2 induced inhibition of ß-catenin protein expression in UMUC3 cell. (E). A time-dependent decrease in ß-catenin protein expression in T24-vector and T24-oeSGK2 cell lines exposed to CHX (10 µg/mL). However, the decrease speed was marked slower in T24-oeSGK2 than T24-vector group. (F). The expression of c-Myc and CTNNB1 gene (encoding ß-catenin protein) were significantly associated with tumor stage of bladder cancer (P < 0.05). (G). c-Myc expression was significantly associated with overall survival (OS), recurrence-free survival (RFS) in bladder cancer patients (P < 0.05). Upper and middle indicated protein expression analysis and lower indicated gene expression analysis.

Fig 4: SGK2 promotes bladder cancer cells migration and invasion abilities in vitro. (A). Wound healing assays indicated cell migration was inhibited after knocking down SGK2 in UMUC3 and J82 cell lines (P < 0.05). Inversely, cell migration was significantly increased after overexpressing SGK2 in T24 cell line (P < 0.01). (B). Transwell assays indicated cell migration was inhibited after knocking down SGK2 in UMUC3 and J82 cell lines (P < 0.01). Inversely, cell migration was significantly increased after overexpressing SGK2 in T24 cell line (P < 0.05). (C). Transwell assays indicated cell invasion was inhibited after knocking down SGK2 in UMUC3 and J82 cell lines (P < 0.01). Inversely, cell invasion was significantly increased after overexpressing SGK2 in T24 cell line (P < 0.05). Data are representative of three independent experiments. * indicated P < 0.05. ** indicated P < 0.01.

Fig 5: SGK2 promotes bladder cancer cell growth and colony formation (CF) abilities in vitro. (A). MTT assays indicated cell growth was inhibited after knocking down SGK2 in UMUC3 and J82 cell lines (P < 0.05). (B). Cell growth was significantly increased after overexpressing SGK2 in T24 cell line using MTT assay (P < 0.05). (C). The colony formation (CF) assay indicated knocking down SGK2 significantly decreased CF ability in UMUC3 (P < 0.01) and J82 cells (P < 0.05). (D). CF ability was significantly increased after overexpressing SGK2 in T24 cell line (P < 0.05). Data are representative of three independent experiments. * indicated P < 0.05. ** indicated P < 0.01.