TP53 and malignant colon neoplasm: As part of our ongoing efforts in developing spirooxindoles to activate p53 (Ribeiro et al., 2012, 2014, 2016b, 2017; Monteiro et al., 2014), we have recently developed a library of spiropyrazoline oxindoles that induce cell cycle arrest in HCT116 colon cancer cells by partially inhibiting the p53-MDM2 protein-protein interaction in live cells (Nunes et al., 2017).