Anticancer activity of ethyl acetate extract from Lethariella cladonioides in vitro and in vivo

Background: Lethariella cladonioides, also known as Red Snow Tea and Golden Silk Tea, mainly grows in Tibet, Sichuan and Yunnan of China. Its medicinal value has been gradually discovered. Objectives: This study mainly evaluated the anti-cancer effect of AMH-L extracted from L. cladonioides in vitro and in vivo and to explore its anticancer mechanism. Materials and Methods: MTT assay was used to determine the cytotoxicity of AMH-L to human cancer cells A-549 and HCT-116 in vitro. Sarcoma S-180 and human lung cancer NCL-H460 cells were implanted into Kunming mice and Balb/C nude mice, respectively, anti-cancer activity in vivo was assessed by recording body weight, organ coefficient and tumor inhibition rate. Flow cytometry and western blotting were used to preliminarily explore the anticancer mechanism. Results: AMH-L, the active component of Red Snow Tea, had strong anticancer activity against A-549 and HCT-116, and IC50was 26.17 +/- 3.54 and 16.21 +/- 0.83. When the dosage was 50, 100 and 150 mg/kg, the inhibition rates of S-180 in Kunming mice were 36.04%, 43.14%, and 50.45% in turn, respectively. At the end of the experiment, the dose was 150, and the relative proliferation inhibition rate of Balb/C nude mice NCI-H460 tumor was 50.36%. Cell cycle and apoptotic results showed that AMH-L could block A-549 at G2/M phase and promote apoptosis of HCT-116 by inducing poly (ADP-ribose) polymerase lysis. Conclusion: L. cladonioides extract AMH-L exhibits strong anticancer activity in vivo and in vitro and can be used as a potential anticancer drug for further study.