[Inhibitory effects of Aspisol on growth of transplanted breast cancer in C3H mice].

Background & Objective: Cyclooxygenase (COX) plays an important role in tumorigenesis and development. Many inhibitors of COX could inhibit proliferation and induce apoptosis of cancer cells. This study was to observe the inhibitory effect of Aspisol on growth of transplanted breast cancer in C3H mice and the effects of Aspisol on tumor cell apoptosis and the expression of Caspase-3 and COX-2, and explore the mechanisms.

Methods: The suspension of breast cancer cells was injected subcutaneously into forelimb axillas of C3H mice to establish xenograft models. From the next day, the mice received intraperitoneal injection of different concentrations of Aspisol once a day for 28 days; the mice received injection of 5-fluorouracil (5-FU) were used as positive controls, and the mice received injection of normal saline (NS) were used as negative controls. The inhibition rate of tumor growth was calculated. Tumor cell apoptosis was detected by TUNEL assay. The expression of Caspase-3 and COX-2 was detected by immunohistochemistry.

Results: The inhibition rate of tumor growth was 38.9% in 175 mg/kg Aspisol group, 48.2% in 350 mg/kg Aspisol group, 47.0% in 700 mg/kg Aspisol group, and 60.4% in 10 mg/kg 5-FU group. Typical apoptotic morphologic changes were seen in the 4 groups. Caspase-3 expression was significantly higher and COX-2 expression was significantly lower in Aspisol groups than in NS group.

Conclusions: Aspisol may inhibit the growth of transplanted breast cancer in C3H mice, and induce tumor cell apoptosis. The mechanism may be correlated to down-regulation of COX-2 and up-regulation of Caspase-3.