Solute carrier family 6 member 3 promotes the development of clear cell renal cell carcinoma by enhancing glycolysis and inhibiting ferroptosis.

OBJECTIVE: Clear-cell renal cell carcinoma (ccRCC) is the most prevalent type of renal cancer. Solute carrier family 6 member 3 (SLC6A3) is associated with ccRCC. This research aimed to investigate the function of SLC6A3 in promoting the metabolism and development of ccRCC tumor cells. MATERIAL AND METHODS: SLC6A3 expression levels in ccRCC cell lines were assessed through quantitative real-time polymerase chain reaction and Western blot (WB). A stable overexpression of SLC6A3 was achieved in the 786-O cell line, and stable knockdown was established in the OS-RC-2 cell line through lentiviral transfection. Cell biological behavior was evaluated through flow cytometry, terminal deoxynucleotidyl transferase media dUTP nick end labeling staining, Cell counting kit-8 assays, and Transwell assays. Extracellular acidification rate measurements, WB, and biochemical assays were performed to detect cellular glycolysis and ferroptosis following alterations in SLC6A3 expression. The effects of SLC6A3 overexpression or knockdown on ccRCC tumor were further verified in xenograft models using nude mice. RESULTS: SLC6A3 was elevated in various ccRCC cell lines. The 786-O cells exhibited a relatively low baseline SLC6A3 expression (P < 0.01), which prompted subsequent overexpression experiments, whereas OSRC-2 cells showed the highest baseline expression (P < 0.001), which led to subsequent knockdown studies. The overexpression of SLC6A3 in 786-O cells increased the glycolytic activity, decreased ferroptosis levels, and promoted viability and invasion of ccRCC cells. Conversely, knockdown of SLC6A3 in OS-RC-2 cells reduced glycolytic activity, increased ferroptosis levels, and inhibited viability and invasion of ccRCC cells. All results were statistically significant. These findings were corroborated by in vivo experiments. CONCLUSION: SLC6A3 is markedly overexpressed in ccRCC. It influences the promotion of tumor growth by enhancing glycolysis and suppressing ferroptosis. These insights highlight the potential of SLC6A3 for innovative therapeutic strategies in ccRCC management.