1. Irreversibility of arsenic trioxide induced PML/RARα fusion protein solubility changes
- Author
-
Li Ya Ma, Yasen Maimaitiyiming, Hua Naranmandura, Yi Ming Shao, Xiao Yang Lu, Na Bu, Qian Qian Wang, Yu Jiang, and Wei Zhong Chen
- Subjects
inorganic chemicals ,0301 basic medicine ,Acute promyelocytic leukemia ,Oncogene Proteins, Fusion ,Biophysics ,chemistry.chemical_element ,Antineoplastic Agents ,Apoptosis ,Protein degradation ,Biochemistry ,Biomaterials ,HeLa ,03 medical and health sciences ,Promyelocytic leukemia protein ,chemistry.chemical_compound ,Arsenic Trioxide ,Leukemia, Promyelocytic, Acute ,Cell Line, Tumor ,medicine ,Humans ,Solubility ,Arsenic trioxide ,Arsenic ,integumentary system ,030102 biochemistry & molecular biology ,biology ,Chemistry ,Metals and Alloys ,Cell Differentiation ,medicine.disease ,biology.organism_classification ,Fusion protein ,Molecular biology ,HEK293 Cells ,030104 developmental biology ,Chemistry (miscellaneous) ,biology.protein ,HeLa Cells - Abstract
Arsenic trioxide (As2O3) is one of the most effective drugs for the treatment of acute promyelocytic leukemia (APL), and induces the degradation of chimeric oncoprotein PML/RARα (P/R) and APL cell differentiation. Recent evidence has suggested that P/R fusion protein degradation by arsenic occurs through two steps, namely, rapid solubility change/shift of the P/R fusion protein following arsenic treatment (i.e., transfer of P/R protein from the soluble fraction to the insoluble pellet fraction), and subsequent degradation of these insoluble proteins. However, there is little information regarding the reversibility of arsenic induced P/R fusion protein solubility change as well as protein degradation in the insoluble fraction after removing arsenic. In this study, we used APL cell line NB4 or P/R and PML over-expressed 293T cells as well as HeLa cells to reveal the solubility change of P/R and PML by arsenic exposure, and further determined the fate of these insoluble proteins after the removal of arsenic. Here, for the first time, we found that arsenic induced P/R or PML protein solubility change is an irreversible process. Once arsenic induces a P/R or PML protein solubility change, these insoluble proteins could be degraded by the proteasomal pathway even without continuous arsenic treatment. However, PML and P/R proteins can be newly synthesized after the removal of arsenic, suggesting that great caution should be taken in the clinical therapy of APL patients before ending arsenic treatment.
- Published
- 2019