Antitumor Effects of β-Elemene Through Inducing Autophagy-Mediated Apoptosis in Ewing Sarcoma Family Tumor Cells

Ewing sarcoma family tumors (ESFTs) are a group of aggressive tumors mainly affecting children and young people. A compound derived from Curcuma wenyujin plant or lemon grass, beta-elemene, has exhibited antitumor effects to ESFT cells, the mechanism of which remains to be clarified further. Autophagy is involved in the antitumor effects of various drugs, whereas the role of autophagy in the antitumor effects of beta-elemene persists controversial. Herein we found that beta-elemene treatment inhibited the viability of ESFT cells in a dosedependent manner. The increase of LC3-II level and the decrease of p62 level were observed in beta-elemenetreated cells, as well as the increase of autolysosomes, which indicated the promotion of autophagic flux. Sequentially the autophagy inhibition using 3-MA treatment or ATG5 depletion significantly reversed the viability repression and apoptosis induction by beta-elemene treatment. In addition, autophagy was found to be important in the toxic effects induced by the combination treatment of beta-elemene and IGF1R inhibition in ESFT cells. Our data suggested an essential role of autophagy in beta-elemene-induced apoptosis in ESFT cells, which is anticipated to provide novel insights to the development of ESFT treatments.

Automated summary

This study revealed the antitumor effects of beta-elemene derived from Curcuma wenyujin plant or lemon grass on Ewing sarcoma family tumors (ESFTs). It was found that autophagy plays an important role in the beta-elemene-induced apoptosis in ESFT cells. This research provides novel insights for the development of ESFT treatments.