Abstract 5892: miR-217 sensitizes chronic myelogenous leukemia cells to tyrosine kinase inhibitors by targeting pro-oncogenic anterior gradient 2

Abstract

Abstract BCR-ABL1 independent mechanisms had been indicated to mediate drug resistance to tyrosine kinase inhibitors (TKIs) in patients with chronic myelogenous leukemia (CML). In this study, we observed increased level of pro-oncogenic anterior gradient 2 (AGR2) in TKIs-resistant CML cells. Silencing of AGR2 in dasatinib-resistant K562 (K562DR) cells led to restored sensitivity to dasatinib both in vitro and in vivo. Exposure to dasatinib induced up-regulation of AGR2 in K562 cells, which indicated a probable treatment related drug resistance. We further investigated the potential interaction between microRNA (miRNA) and AGR2 in K562DR cells, and found that down-regulation of miR-217 was associated with over-expression of AGR2 in K562DR cells. Luciferase reporter assay identified that miR-217 negatively regulated expression of AGR2 through binding 3'-untranslated region (3'-UTR) of AGR2. Forced expression of miR-217 led to decreased expression of AGR2 as well as compromised TKIs-resistant potential of K562DR cells. Similarly, over-expression of miR-217 re-sensitized K562DR cells to dasatinib-treatment in a murine xenograft transplantation model. Taken together, TKIs-treatment induced drug-resistance is correlated with decrease of miR-217 and up-regulation of AGR2. miR-217/AGR2 interaction might be a potential therapeutic target in treating CML patients with TKIs-resistant. Citation Format: Bin Pan, Xiangmin Wang, Kailin Xu, Takayuki Ikezoe. miR-217 sensitizes chronic myelogenous leukemia cells to tyrosine kinase inhibitors by targeting pro-oncogenic anterior gradient 2 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5892.