Antitumor Activity of Royal Jelly and Its Cellular Mechanisms against Ehrlich Solid Tumor in Mice

OBJECTIVE: The present study was aimed at evaluating the antitumor effects of royal jelly (RJ) obtained from Apis mellifera compared with cyclophosphamide against the Ehrlich solid tumors (EST) in mice. METHODS: Tumor growth inhibition, body weight, the serum level of alpha-fetoprotein (AFP) and carcinoembryonic antigen tumor (CAE), liver and kidney enzymes, tumor lipid peroxidation (LPO), nitric oxide (NO), antioxidant enzymes (glutathione peroxidase (GPx), catalase enzyme (CAT), and superoxide dismutase enzyme activity (SOD)), tumor necrosis factor alpha level (TNF-α), and the apoptosis-regulatory genes expression were assessed in EST mice treated with RJ (200 and 400 mg/kg orally once a day for 2 weeks). RESULTS: The results showed that treatment of EST-suffering mice with RJ at the doses of 200 and 400 mg/kg causes significant reduction in tumor volume and inhibition rate, body weight, tumor markers (AFP and CEA), serum level of liver and kidney, LPO and NO, TNF-α level, as well as the expression level of Bcl-2 in comparison with the EST mice receiving the normal saline; whereas RJ at the doses of 200 and 400 mg/kg/day significantly increased (p < 0.05) the level of antioxidant enzymes of GPx, CAT, and SOD and the expression level of caspase-3 and Bax genes. CONCLUSION: The findings revealed that oral administration of royal jelly especially at the doses of 200 and 400 mg/kg exhibited promising antitumor effects against EST in mice through induction of apoptosis as well as its antioxidant and anti-inflammatory effects, which suggest it as a novel anticancer agent against tumor; however, additional surveys especially in clinical setting are necessary to approve these findings.