TFF2 and malignant colon neoplasm: Thus, sulindac sulfide was the most active sulindac derivative as observed in previous studies [33, 34] and the results suggest that the growth inhibitory effects of sulindac sulfide are correlated with downregulation of pro-oncogenic Sp proteins, and previous studies show that knockdown of one or more [35, 36] Sp proteins in colon cancer cells decreases cell cycle progression and induces apoptosis.