miR­101 regulates the cell proliferation and apoptosis in diffuse large B­cell lymphoma by targeting MEK1 via regulation of the ERK/MAPK signaling pathway.

MAPK kinase 1 (MEK1) is an upstream protein kinase of extracellular signal regulated kinase (ERK), which activates the ERK/MAPK (mitogen activated protein kinase) pathway. Importantly, bioinformatic analysis has shown that there is a target complementary binding site between miR­101 and MEK1. The present study aimed to ascertain whether or not miR­101 plays a role in regulating MEK1 expression, ERK/MAPK pathway activity, and the proliferation and apoptosis in a diffuse large B cell lymphoma (DLBCL) cell line. DLBCL tumor samples were collected from patients in our hospital, and lymphatic tissues with reactive lymphoid hyperplasia were selected as controls. The patients were divided into high and low expression groups, and then the survival rate of the two groups was compared using Kaplan­Meier method, as well the effect of miR­101 and MEK1 mRNA expression on survival and prognosis was analyzed. The expression of miR­101, MEK1 and p­MEK1 between normal lymphoblastic cell lines (HCC1954 BL and NCI­BL2009) and lymphoma cell lines (SU­DHL­4 and Farage) was compared. Lymphoma SU­DHL­4 and Farage cells were cultured in vitro, and then divided into the following groups: miR­NC group; miR­101 mimic group; siRNA­NC group; and siRNA­MEK1 group. The expression of miR­101, MEK1, p­MEK1, p­ERK1/2 and Bcl­2 was compared. Cell apoptosis was detected by flow cytometry, and cell proliferation was detected by EdU staining. The results showed that targeted regulation existed between miR­101 and MEK1, and the decreased expression of miR­101 was related to the pathogenesis and prognosis of DLBCL. Upregulation of miR­101 inhibited DLBCL cell proliferation and facilitated apoptosis by inhibiting the expression of MEK1.