Objective: To investigate the inhibitory effect of bufalin on the proliferation of human colorectal cancer cell, HCT116, and its relationship with expression of insulin-like growth factor 2 (IGF-2) and type 1 receptor (IGF1R). Methods: HCT116 cells were cultured with bufalin and cell proliferation was measured by MTT assay. The inhibitory rate of cell proliferation and the half maximal inhibitory concentration (IC50) were calculated. Cell cycle was determined by use of flow cytometry. mRNA and protein expressions of IGF-2 and IGF1R were analyzed by real time polymerase chain reaction (PCR) and Western Blot, respectively. The distribution of IGF-2 and IGF1R in cells was also observed by immunocytochemical staining. Results: The IC50 of bufalin at 24, 36, 48, 60, and 72 hours were 0.79±0.10, 0.37±0.10, 0.25±0.03, 0.17±0.02, and 0.10±0.03 uM, respectively. We selected 0.3 uM and 48 hours as the concentration of bufalin and culture time in following experiments. When cultured with bufalin, the ratio of cells in G2 phase to cells in M phase was increased in a dose dependent manner, indicating a delay from G2 to M caused by bufalin. For IGF-2, the mRNA and protein expressions were increased when cells were cultured with bufalin; For IGF1R, the mRNA increased but protein decreased. Both IGF-2 and IGF1R were seen in cytoplasm. Conclusion: Bufalin can significantly inhibit the proliferation of HCT116 cells, its underlying mechanism may relate with the up-regulation of IGF-2 expression and down-regulation of IGF1R protein expression.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1077. doi:1538-7445.AM2012-1077

©2012 American Association for Cancer Research
2012