Knockdown of Diaph1 expression inhibits migration and decreases the expression of MMP2 and MMP9 in human glioma cells.

As the most common primary central nervous system tumor, glioma is characterized by high levels of mortality and migration. Unclear boundary with normal brain tissue results in poor treatment. The mammalian diaphanous-related formin 1 (Diaph1) which belongs to formin-homology protein family, is a target of RhoA and involved in a number of actin-related biological processes, which abnormally expressed in pathological conditions in a number of tumors. Immunohistochemical analysis showed that Diaph1 was overexpressed in glioma tissues compared with normal human brain tissue. Diaph1 gene silencing RNA interference (RNAi) significantly inhibited the migratory activity of human glioma cell lines U87 and U251. Moreover, data obtained from qRT-PCR and Western-blot analysis showed that the mRNA and protein expression of matrix metalloproteinase2 and 9 (MMP2 and MMP9) was significantly suppressed in these Diaph1 knockdown cell lines, as well as gelatin zymography analysis revealed that the activity of MMP2 and MMP9 in conditioned medium was markedly decreased. In conclusion, our data demonstrate that Diaph1 is highly expressed in human glioma, plays a significant role in glioma cell migration, and can influence the expression and activity of MMP2 and MMP9 indirectly in human glioma cell lines U87 and U251. We provide a theoretical basis for further experimental studies and Diaph1 using on glioma therapy.