Therapeutic effect of Arthrocnemum machrostachyum methanolic extract on Ehrlich solid tumor in mice

Background: The anti-cancer effect of the halophyte Arthrocnemum indicum, a member of Arthrocnemum family of salt-tolerant plants, was evaluated against colorectal cancer cell, CaCo2. However, the anti-cancer effect of another halophyte Arthrocnemum machrostachyum was not investigated yet. Herein, the anticancer effect of A. machrostachyum methanolic extract (AME) was evaluated against Ehrlich solid tumor (EST) in mice and the potential mechanism of action was also studied.

Methods: Male Swiss albino mice (n = 28) were randomly divided into 4 groups (n = 7/group). Group 1 (negative control group); group 2 (EST) injected intramuscularly by 0.2 mL Ehrlich ascitic carcinoma (2 × 10⁶ cells); and groups 3 and 4 injected intratumorally with AME (180 and 360 mg/kg body weight, respectively) at D12 trice weekly for 2 weeks. Gene expression, protein expression, DNA damage, and TNFa level in tumors were determined by real-time PCR, western blot, comet assay, and Elisa, respectively.

Results: Treatment with AME induced anti-tumor effects against EST as indicated by 1) notable reduction in tumor size; 2) elevation in tissue necrosis and apoptosis, as confirmed histologically; 3) increased DNA fragmentation; 4) decreased expression of the apoptotic genes (p53, Bax and caspase 3), and increased expression of the anti-apoptotic marker Bcl2; 5) significantly upregulated cell cycle regulatory genes Cdc2 and connexin26, and; 6) decreased TNFa levels in tumor tissues. Interestingly, a high dose of AME exhibited a more potent anti-tumor effect against EST.

Conclusion: These findings indicate that AME has a potent antitumor effect against EST and could be used as an adjuvant to anticancer drugs to combat tumor, but after application of further confirmatory clinical trials.

Keywords: Apoptosis; Arthrocnemum machrostachyum; Ehrlich solid tumor; Inflammation.