Ebracteolatain A Inhibits Lung Cancer Growth via p21 and p27 Mediated Cell-Cycle Arrest

Abstract

Objective: Lung cancer is a refractory tumor with a poor five-year survival rate. Ebracteolatain A (EA), a key acetyl-phloroglucinol derived from the traditional Chinese herb Langdu, has been reported to have anti-tumor activity in human breast cancer. However, the therapeutic efficacy and underlying mechanism of lung cancer remain to be elucidated. In the present study, we intended to evaluate whether EA exhibits anti-lung cancer activity and elucidate the underlying mechanisms. Methods: ATPlite and clonogenic survival assays were used to assess the inhibiting effect of EA on two lung cancer cell lines in vitro. FACS was conducted to determine the cell-cycle profiling of lung cancer cells upon treatment with EA. Western blot was performed to detect the level of related proteins in EA-treated lung cancer cells. RNA silencing and other experiments were used to identify the molecular mechanism of EA-triggered cell-cycle arrest. Furthermore, a xenograft tumor model was constructed to evaluate the therapeutic effect and potential mechanism of EA in vivo in mice. Results: EA significantly inhibited the growth of lung cancer cells both in vitro and in vivo. Mechanistically, EA-induced G1 phase cell-cycle arrest is mediated by the accumulation of p21 and p27. Conclusion: Our findings revealed the anti-lung cancer effect of EA and the mechanisms, providing a solid scientific basis for EA as an attractive choice for lung cancer therapy.