STUDY ON THE INHIBITORY EFFECT OF INOSITOL HEXAPHOSPHATE ON THE GROWTH OF SUBCUTANEOUS TRANSPLANTED TUMOR OF HT-29 CELL IN NUDE MICE

Objective To investigate the inhibitory effect of inositol hexaphosphate on the growth of subcutaneous transplanted tumor of HT-29 cell in nude mice. Method Established models of subcutaneous transplantable HT-29 cell tumor in nude mice and the mice were divided randomly into four groups:control group,5-fluorouiaical(5-FU) group,low-dose IP6 group,high dose IP6 group,eight animals per each group,0.5 ml containing normal saline,5-FU 20 mg/kg bw,IP6 40 mg/kg bw and IP6 100mg/kg bw was administered i.p. respectively to above groups once daily. After continuous administration for 20d,the mice were killed. The anti-tumor effect in each group was observed and Specimens were detected by light microscopy and electron microscopy,Hoechst staining,TUNEL and immunohistochemical method. Results The tumor weights and volumes in control group,low-dose IP6 group,high-dose IP6 group and 5-FU group were 0.68±0.31,0.57±0.28,0.58±0.18,0.24±0.23g. and 0.71±0.35,0.58±0.21,0.59±0.20,0.34±0.27 cm3 respectively. Compared with the control group,the weight and volume of tumors in 5-FU group were decreased significantly (P0.05). The weight and volume of tumors in IP6 groups showed a reduction trend,but not significant statistically. Compared with the control group,P53 protein expression in low-dose and high-dose IP6 groups was significantly reduced (P0.05),but PCNA protein expression was not different significantly. TNUEL detection showed that apoptosis rate in IP6 groups were significantly higher than control group (P0.05). Conclusion IP6 could inhibit the growth of HT-29 cell implanted tumor mildly through inducing cell apoptosis and reducing expression of P53.