miR-125a-5P regulated epidermal growth factor receptor signal pathway by targeting growth factor receptor-bound protein 10 in medulloblastoma

Objective To explore the regulation mechanism for miR-125a-5P in epidermal growth factor receptor(EGFR) signaling pathway in medulloblastoma. Methods The potential targets of miR-125a-5P in the EGFR signaling pathway were predicted by TargetScan and Sanger software, there were 3 groups: control group, non-sense group and miR-125a-5P group.Their relationship, between miR-125a-5P and cyclin-dependent kinase inhibitor 2B (CDKN2B), E2F transcription factor 3(E2F3), mitogen-activated protein kinase 14(MAPK14) and growth factor receptor-bound protein 10(GRB10), were tested by luciferase experiments.After miR-125a-5P oligonucleotide was transfected to D341 cells, miR-125a-5P level was detected by reverse transcription polymerase chain reaction.Then the thiazolyl blue tetrazolium bromide assay was used to draw the cell growth curves, and Transwell assay was used to detect cell migration ability.The expression levels of GRB10, EGFR, phosphatidylinositol 3-kinase(PI3K) and Ras were tested by Western blot method. Results The results of luciferase experimental results showed that GRB10 was the only target gene of miR-125a-5P.After miR-125a-5P being transfected, the D341 cell proliferation obviously declined markedly.Compared with control group [(38.16±7.47)%] and the non-sense group [(36.79±8.94)%], cell migration rate in the miR-125a-5P group was lowest [(13.59±4.41)%], and there was a significant difference among 3 groups(χ2=11.495, P<0.05); in the miR-125a-5P group, the expression level of EGFR increased 1.67 times, GRB10, PI3K and Ras levels were reduced to 23%, 61% and 42%. Conclusion miR-125a-5P can inhibit tumor growth by silenced GRB10 expression targeting EGFR downstream signaling pathways in medulloblastoma. Key words: Medulloblastoma; Proliferation; Metastasis; Micro RNA