1. Nicotine increases the resistance of lung cancer cells to cisplatin through enhancing Bcl-2 stability
- Author
-
Takashi Nishioka, Mariyannis A, Dai W, Luo Ly, Chen C, Shen L, and He H
- Subjects
Cancer Research ,Nicotine ,Keap1 ,Lung Neoplasms ,cisplatin ,Antineoplastic Agents ,Apoptosis ,Biology ,03 medical and health sciences ,Mice ,0302 clinical medicine ,medicine ,Tumor Cells, Cultured ,Animals ,Humans ,Bcl-2 ,Cytotoxicity ,Protein kinase B ,Molecular Diagnostics ,030304 developmental biology ,Cisplatin ,0303 health sciences ,Cell growth ,Protein Stability ,Akt ,Ubiquitination ,chemoresistance ,KEAP1 ,3. Good health ,Up-Regulation ,Oncology ,Proto-Oncogene Proteins c-bcl-2 ,Drug Resistance, Neoplasm ,030220 oncology & carcinogenesis ,Cancer cell ,Immunology ,Cancer research ,Protein Processing, Post-Translational ,medicine.drug - Abstract
Background: Nicotine is able to activate mitogenic signalling pathways, which promote cell growth or survival as well as increase chemoresistance of cancer cells. However, the underlying mechanisms are not fully understood. Methods: In this study, we used immunoblotting and immunoprecipitation methods to test the ubiquitination and degradation of Bcl-2 affected by nicotine in lung cancer cells. Apoptotic assay was also used to measure the antagonising effect of nicotine on cisplatin-mediated cytotoxicity. Results: We demonstrated that the addition of nicotine greatly attenuated Bcl-2 ubiquitination and degradation, which further desensitised lung cancer cells to cisplatin-induced cytotoxicity. In this process, Bcl-2 was persistently phosphorylated in the cells cotreated with nicotine and cisplatin. Furthermore, Akt was proven to be responsible for sustained activation of Bcl-2 by nicotine, which further antagonised cisplatin-mediated apoptotic signalling. Conclusions: Our study suggested that nicotine activates its downstream signalling to interfere with the ubiquitination process and prevent Bcl-2 from being degraded in lung cancer cells, resulting in the increase of chemoresistance.
- Published
- 2013