TP53BP1 and neoplasm: Results showed efficient Ki67 and nuclear staining in tumor sections, while the number of Ki67 positive cells was substantially less in 4a treated tumors (Fig. 7A, B). Further, we observed that the expression of p53 binding protein 1 (53BP1), and proapoptotic protein, BID was significantly high following treatment with 4a in tumor tissues (25th day of treatment) as compared to untreated tumor tissue (Fig. 7C–F), further suggesting the activation of apoptosis in tumor cells in mice. Therefore, our results show that 4a treatment significantly inhibits tumor progression in mice.