Figure 1. Chronic exposure to AS promotes the proliferation of HT-29 cell lines. (A and B) HT-29 cells were exposed to 0 or 15 nM AS for 0, 30, and 60 passages. In the MTT assay, AS increased the HT-29 cell proliferation, especially in AS (60).*P < 0.05; **P < 0.01. (C–E) Similarly, cell cycle analysis suggested that chronic AS treatment accelerated cell re-entering into the S phase.*P < 0.05. (F–I) In soft agar culture, chronic AS exposure increased the soft agar colony formation of the HT-29 cells, especially in AS (60) cell.*P < 0.05; **P < 0.01. (J–M) Chronic AS exposure increases the plate colony formation rate of the HT-29 cells, especially in AS (60) cell. *P < 0.05;**P < 0.01.