Sesquiterpene lactones of Moquiniastrum polymorphum subsp floccosum have antineoplastic effects in Walker-256 tumor-bearing rats

Background and aim: This study aimed to evaluate the in vivo antitumor actions and toxicity of the dichloromethane fraction (F1 B) of Moquiniastrum polymorphum subsp. floccosum (formerly Gochnatia polymorpha ssp. floccosa), composed of sesquiterpene lactones, against Walker-256 carcinosarcoma in rats. Methods: Male Wistar rats received 100 mg kg(-1) F1 B per day orally for 16 days after subcutaneous inoculation of Walker-256 cells in the pelvic limb. The tumor progression was monitored, and after treatment, tumor weight, oxidative stress, plasma biochemistry, inflammatory parameters, gene expression and histology of tumor and/or liver were evaluated. The toxicity of F1 B was analyzed through the relative weight of organs. Additionally, an LD50 test was performed in mice. Results: F1 B treatment significantly reduced tumor volume and weight. There was no difference in oxidative stress in tumor tissue after treatment. F1 B treatment modified hepatic glutathione and superoxide dismutase, and normalized plasma glucose, alkaline phosphatase, and amylase. F1 B did not affect the activity of myeloperoxidase and N-acetylglucosaminidase or the nitric oxide levels in tumor tissue. However, F1 B decreased the tumor necrosis factor (TNF)-alpha levels. Additionally, F1 B increased apoptosis in the tumor, mediated by up-regulation of the p53 and Box gene expression. No clinical signs of toxicity or death were observed in the rats treated with F1 B. The LD50 calculated for mice was 1209 mg kg(-1). Conclusions: F1 B, which is rich in sesquiterpene lactones, showed antitumor activity against Walker-256 carcinosarcoma. This effect may be, at least in part, related to the induction of apoptosis and inhibition of TNF-alpha signaling. (C) 2015 Published by Elsevier Ireland Ltd.