Synergistic effect between cetuximab and curcumin on experimentally induced hamster buccal pouch carcinoma

The aim of the present study was directed to investigate the therapeutic efficacy of cetuximab and curcumin either in combination or alone as anticancer treatment mmodality on 7,12-dimethylbenz[a]anthracene (DMBA) induced hamster buccal pouch(s) (HBP(s)) carcinoma. Material and methods: Twenty-Five Syrian male hamsters, five weeks old, weighing 80-120g were divided into three group(s) (G(s)): A, B, and C. G-A (negative control): HBP mucosa of 5 animals were painted with liquid paraffin alone three times a week for 18 weeks. G-B: 20 right HBP animals were painted with 0.5% DMBA in paraffin oil 3 times a week for 18 weeks. Then animals were divided randomly into four sub-groups. G-B1 (DMBA treated group): 5 animals were left untreated for 6 weeks after DMBA painting. G-B2 (cetuximab treated group): 5 animals were injected intraperitoneally with cetuximab
1 mg/animal at 3 days intervals for 6 weeks following DMBA-treatment. G-B3 (curcumin treated group): Right HBP of 5 animals were directly injected with curcumin 80 mg/kg body weight every day for 6 weeks following DMBA-treatment. G-B4 (curcumin-cetuximab treated group): 5 animals were directly injected with curcumin followed by intraperitoneal injection of cetuximab for 6 weeks following a DMBA-treatment. The assessment was based on the gross observation, histological and immunohistochemical examination utilizing anti-apoptotic Bcl-2 antibody. Results: Gross observation revealed variation in reduction of the tumor size in the treated groups (G-B2, G-B3, and G-B4) compared to that observed in group G-B1. Histopathological findings revealed variations among the treated groups. Immunohistochemical results revealed that Bcl-2 expression has a variability in the area % throughout the groups used. Groups G-B1, G-B2, G-B3 and G-B4 were 70.7 %, 54.8 %, 42.7% and 24.5% respectively. Conclusion: The synergistic effect of both cetuximab and curcumin resulted in promising therapeutic effect in regression of DMBA induced HBP carcinoma.