A Representative images of MGC-803 cells cultured in serum-free medium for 7 days and stimulated by rIL-17B or PBS. B Statistical analysis of the spheroid number (diameter > 50 μm) according to figure subpart A (n = 6; ***p < 0.001). C–E Flow cytometric analysis of the expression of Lgr5, CD133, and CD90 in MGC-803 cells treated with different concentrations of rIL-17B (n = 3; ***p < 0.001). F, G qRT-PCR was performed to detect the expression of CK18 and MUC1 in MGC-803 cells treated with different concentrations of rIL-17B (n = 3; **p < 0.01; ***p < 0.001). H Representative images showing the general number and size of spheroids in MGC-803 cells infected with shIL-17RB or shControl lentiviral vectors and stimulated with different concentrations of rIL-17B for 7 days. I Statistical analysis of the number of spheroids (diameter > 50 μm) based on figure subpart H (n = 6; ***p < 0.001).