CURCUMINE REDUCES THE GROWTH OF COLORECTAL LIVER IMPLANTS IN RATS

INTRODUCTION Some plant-based antioxidants, such as curcumin, have shown anti-tumour properties against breast carcinomas and gliomas. The aim of this piece of work is to assess the anti-tumour effect of curcumin on CC531 colorectal cancer cells, both in vitro and in vivo. MATERIAL AND METHODS On CC531 cultures, cell viability was analysed, as well as cell migration capacity (wound healing test), 24, 48 and 72 hours after treatment with curcumin (15, 20, 25 or 30 µM). Additionally, in WAG/RijHsd rats bearing CC531-induced liver implants, total and individual liver lobe tumour volume was quantified in untreated and curcumin-treated animals (200 mg/kg/day, oral). Furthermore, serum enzyme measurements (GOT, GPT, glucose, bilirubin, etc.) were carried out to assess possible effects on liver function. ANOVA and t tests were used to analyse the effects of curcumine treatment. RESULTS In vitro studies showed curcumin's greatest effects 48h after application, when all tested doses reduced cell proliferation by more than 30% (0.443±0.06 vs. 0.319±0.04, 0.302±0.06, 0.274±0.06 and 0.243±0.03, respectively; p < 0.0001). At 72 hours, the highest doses of curcumin (25 and 30 µM) reduced cell viability to less than 50%. Wound healing test also showed that curcumine also inhibits migration capacity. In vivo, curcumin reduced by 5.6 fold the tumour volume of liver implants (7.98±1.45 vs 1.41±1.33; p < 0.0001); however, the volume of healthy liver tissue was higher in untreated animals (10.91±1.01 vs 8.80±1.06; p > 0.01). CONCLUSIONS Curcumin has shown an anti-tumour effect against liver implants from colorectal cancer, both in vitro and in vivo, in this experimental model.