Enhancement of Aloe Polysaccharide on Inhibitory Effects of Cisplatin on Growth of Lung Adenocarcinoma in Nude Mice

OBJECTIVE To investigate the effects of Aloe polysaccharide (AP) combined with cisplatin(DDP) on the growth of transplanted lung adenocarcinoma in mice and the corresponding mechanism. METHODS The human lung adenocarcinoma mode was established with A549 cell in nude mice. Thirty five female Balb/c-nu mice with lung adenocarcinoma were randomly divided into seven groups: control group; low-dose DDP group (1.0 mg·kg^-1); high-dose DDP group (4 mg·kg^-1); low-dose AP group (10 mg·kg^-1); high-dose AP group(30 m mg·kg^-1); low-dose DDP plus low-dose AP group; low-dose DDP plus high-dose AP group. All the mice were sacrificed at 48 h after the last injection. Subcutaneous tumor was subjected to histological examination. Expressions of p53 and bcl-2 in tumor tissues were detected by immunohistochemistry. RESULTS In every treatment group, tumor growth was suppressed significantly. Compared with control group, intraperitoneal injection of other groups resulted in a significant inhibition of the growth of A549 cells in vivo (P<0.01). The anti-tumor effect of DDP plus AP was significantly enhanced compared with low-dose DDP group(P<0.05), the inhibitory rate was 49.34% and 82.61%, respectively. Compared with control group, expression of both p53 and bcl-2 significantly increased in high-dose AP group (P<0.05), and in DDP plus AP groups it was much more enhanced. High dose DDP group showed some adverse reaction, while other groups did not. CONCLUSION DDP combines with AP can significantly inhibit the growth of transplanted lung adenocarcinoma in mice in vivo, the mechanism is associated with the down-regulation of p53 and bcl-2.