Silencing of phosphoglucose isomerase/autocrine motility factor decreases U87 human glioblastoma cell migration.

Phosphoglucose isomerase/autocrine motility factor (PGI/AMF) is secreted by tumors and influences tumor growth and metastasis. In order to investigate the effects of silencing PGI/AMF on the migration and the sphere forming abilities of human glioblastoma U87 cells, as well as on the side population cells (SPCs), PGI/AMF was silenced using siRNA. Western blot analysis and RT-qPCR were used to assess the expression of PGI/AMF, Akt and SRY (sex determining region Y)-box 2 (SOX2). Wound healing, migration and tumorsphere formation assays were performed to assess invasion and metastatic potential. The proportion of SPCs was determined using Hoechst 33342 dye and flow cytometric analysis. PGI/AMF silencing inhibited the wound healing capacity and migration ability of U87 cells by 52.6 and 80.4%, respectively, compared with the scrambled siRNA (both P<0.001). Silencing of PGI/AMF decreased the proportion of SPCs in the U87 cells by 80.9% (P<0.01). The silencing of PGI/AMF decreased the number and size of tumorspheres by 53.1 and 39.9%, respectively, compared with the scrambled siRNA (both P<0.01). The silencing of PGI/AMF decreased the levels of phosphorylated Akt (-71.9%, P<0.001) compared with the scrambled siRNA, as well as the levels of the stemness marker, SOX2 (-61.7%, P<0.01). Taken together, these findings suggest that PGI/AMF silencing decreases migration, tumorsphere formation as well as the proportion of SPCs in glioblastoma U87 cells. We suggest that the Akt pathway is involved, and our results provide a potential new target for the treatment of glioblastoma.