STC1 and gastric cancer: Serum STC-1 serves as a promising tumor marker in GC and ovarian cancer because its expression is higher in such patients than in patients with benign tumors,303,304 and STC-1 is a potentially useful blood marker for predicting tumor progression and invasion in patients with GC.305 STC-1 overexpression increases proliferation, migration, and colony formation in cancer cells.