Guggulsterone from Commiphora mukul potentiates anti-glioblastoma efficacy of temozolomide in vitro and in vivo via down-regulating EGFR/PI3K/Akt signaling and NF-κB activation

The present study will investigate whether guggulsterone potentiates the anti-glioblastoma efficacy of temozolomide by down-regulating EGFR/PI3K/Akt signaling and NF-κB activation. Materials and

The present study suggested that guggulsterone potentiated anti-glioblastoma efficacy of temozolomide through down-regulating EGFR/PI3K/Akt signaling pathway and NF-кB activation.

Cell viability and proliferation was determined by cell counting Kit-8 and colony formation assays. Cell apoptosis was evaluated by Annexin V/PI and hoechst 33342 staining assays. Molecular techniques such as western blotting and real-time quantitative PCR were used to demonstrate guggulsterone in vitro effect on EGFR/PI3K/Akt signaling and NF-κB activation. Finally, in vivo studies were performed in orthotopic mouse models of glioblastoma.

The results demonstrated that guggulsterone enhanced temozolomide-induced growth inhibition and apoptosis in human glioblastoma U251 and U87 cells. Furthermore, the synergistic anti-glioblastoma efficacy between guggulsterone and temozolomide was intimately associated with the inhibition of EGFR/PI3K/Akt signaling and NF-κB activation in U251 and U87 cells. Our in vivo results on orthotopic xenograft models similarly indicated that guggulsterone potentiated temozolomide-induced tumor growth inhibition through suppressing EGFR/PI3K/Akt signaling pathway and NF-кB activity. Conclusions: The present study suggested that guggulsterone potentiated anti-glioblastoma efficacy of temozolomide through down-regulating EGFR/PI3K/Akt signaling pathway and NF-кB activation.