miR-101 sensitizes K562 cell line to imatinib through Jak2 downregulation and inhibition of NF- κB target genes

In this report, we proposed that miRNA-101 targets Jak2 mRNA and regulates its expression and induces K562 leukemia cell apoptosis. Here, we transduced the K562 cell line with a miR-101-overexpressing vector and evaluated the Jak2 mRNA level. Our results showed that miR-101 overexpression in Bcr–Abl+ cells reduced the Jak2 mRNA level. Moreover, imatinib treatment and miR-101 upregulation led to miR-23a overexpression, which has putative binding site(s) on 3′-untranslated regions (3′-UTRs) of STAT5, CCND1, and Bcl-2 genes. Our results also indicated that miR-101 overexpression inhibited cell proliferation indicated by the MTT assay and promoted apoptosis detected via flow cytometry. Importantly, mRNA expression of NF-kappa B-regulated anti-apoptotic (Bcl-2, Bcl-xl, MCL-1, XIAP, and survivin) and proliferative (c-Myc and CCND1) genes was decreased. These findings suggest that miR-101 ac ts as a tumor suppressor by downregulating Jak2 expression and sensitizing K562 cells to imatinib. Therefore, restoration of miR-101 may be a therapeutic approach for CML treatment.
Source: Tumor Biology - Category: Cancer & Oncology Source Type: research