Vitamin E succinate decreases lung cancer tumor growth in mice

Abstract

Background. In vitro studies have shown that Vitamin E Succinate (VES) arrests lung cancer cellular proliferation; however, in vivo studies have not been performed. This study examined in vivo effects of VES on lung cancer. Methods. An in vitro dose-response curve of human A549 lung cancer tumors to VES was established. A549 tumors were established in the right submammary fat pads of athymic nude mice (C57/BL/6J-Hfh11nu). Seven days postinjection, mice were separated into VES and control groups. VES mice ( n = 12) underwent daily intraperitoneal (IP) injection of 0.1 Ml VES in polyethylene glycol and dimethysulfoxide (7% DMSO, 93% PEG); control mice ( n = 11) were injected with vehicle only. At 27 days, harvested tumors were measured and weighed. Lungs were stained for metastases using hematoxylin-eosin. Tumor volume and weights were compared using a two-sample t test. Tumor growth curves were compared using a mixed model analysis of variance. Results. In vitro studies demonstrated dose-dependent inhibition of A549 cell proliferation by VES (IC 50 18 μg/ml). Final tumor volumes and weights differed significantly between VES and control mice with volumes of 292.9 ± 31.4 mm 3 vs.192.6 ± 20.4 mm 3 ( P = 0.01) and weights of 255.7 ± 37.0 mg versus 168.6 ± 20.0 mg ( P = 0.05), respectively. Tumor growth curves differed significantly ( P < 0.001). Both groups of mice showed pulmonary metastases. Conclusions. Intraperitoneal VES was associated with decreased A549 tumor volume, weight, and growth; however, despite reduced tumor growth, pulmonary metastases were seen in VES-treated mice. Nonetheless, these results suggest that lung cancer patients may benefit from inclusion in eventual clinical studies using VES.