HSPA4 regulated glioma progression via activation of AKT signaling pathway.

Glioma is still an incurable disease with high invasiveness. Heat shock 70 kDa protein 4 (HSPA4) is a member of the HSP110 family, and is associated with the development and progression of various cancers. In the current study, we assessed the expression of HSPA4 in clinical samples, and found that HSPA4 was up-regulated in glioma tissues and correlated with tumor recurrence and grade. Survival analyses demonstrated that glioma patients with high HSPA4 expression had lower overall survival and disease-free survival times. In vitro knockdown of HSPA4 inhibited glioma cell proliferation, mediated cell cycle arrest at G2 phase and apoptosis, and reduced the migration ability. In vivo, the growth of HSPA4-knockdown xenografts was markedly suppressed compared to the tumors formed by HSPA4-positive control cells. Additionally, Gene set enrichment analyses disclosed that HSPA4 was associated with the PI3K/Akt signaling pathway. The regulatory effect of the AKT activator SC79 on cell proliferation and apoptosis was suppressed by HSPA4 knockdown, indicating that HSPA4 is capable of promoting glioma development. In summary, these data showed that HSPA4 is likely to play a pivotal role in the progression of glioma, and consequently may be a promising therapeutic target for glioma therapy.