Depression of oncogenecity by dephosphorylating and degrading BCR-ABL

作者：Gao, Miao; Huang, Zheng-Lan; Tao, Kun; Xiao, Qing; Wang, Xin; Cao, Wei-Xi; Xu, Min; Hu, Jing; Feng, Wen-Li^*

来源：Oncotarget, 2017, 8(2): 3304-3314.

DOI：10.18632/oncotarget.13754

• chronic myeloid leukemia
• BCR-ABL
• Y177
• protein tyrosine phosphatase
• ornithine decarboxylase

Aberrant phosphorylation and overexpression of BCR-ABL fusion protein are responsible for the main pathogenesis in chronic myeloid leukemia (CML). Phosphorylated BCR-ABL Y177 recruits GRB2 adaptor and triggers leukemic RAS-MAPK and PI3K-AKT signals. In this study, we engineered a SPOA system to dephosphorylate and degrade BCR-ABL by targeting BCR-ABL Y177. We tested its effect on BCR-ABL phosphorylation and expression, as well as cell proliferation and apoptosis in CML cells. We found that SPOA remarkably dephosphorylated BCR-ABL Y177, prevented GRB2 recruitment, and uncoupled RAS-MAPK and PI3K-AKT signals. Meanwhile, SPOA degraded BCR-ABL oncoprotein in ubiquitin-independent manner and depressed the signal transduction of STAT5 and CRKL by BCR-ABL. Furthermore, SPOA inhibited proliferation and induced apoptosis in CML cells and depressed the oncogenecity of K562 cells in mice. These results provide evidence that dephosphorylating and degrading oncogenic BCR-ABL offer an alternative CML therapy.

• 出版日期2017-1-10
• 单位重庆医科大学