Protective effect and mechanisms of Weining granule on N-methyl-N'-nitro-N- nitrosoguanidine-induced gastric cancer in rats.

OBJECTIVE: To investigate the protective effect and molecular mechanisms of Weining granule on N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced gastric cancer in rats. METHODS: A total of sixty healthy male wistar rats were randomly divided into five groups, including control group (CG), gastric cancer model group (MG), low-dose Weining granule treated group (LWT), medium-dose Weining granule treated group (MWT), and high-dose Weining granule treated group (HWT). Except the control group, the other groups were treated with MNNG to establish a rat model of gastric cancer. Low-dose Weining granule treated group, medium-dose Weining granule treated group, and high-dose Weining granule treated group were fed 9.0, 18.0 and 36.0 g/kg Weining granule, respectively. Histopathologic and molecular biologic technology were adopted to determine the protective effect of Weining granule on MNNG-induced gastric cancer in rats. The pathological changes of gastrointestinal tissue were observed. Meanwhile, the differential expression of proliferation, apoptosis and angiogenesis markers were determined, including proliferating cell nuclear antigen (PCNA), pokemon, cyclin D1, B-cell lymphoma-2 (Bcl-2), caspase-3, phosphatase and tensin homolog (PTEN) and vascular endothelial growth factor (VEGF). RESULTS: After the MNNG treated, the pathological changes of stomach tissue were improved noticeably, including the intestinal metaplasia and atypic hyperplasia. The experiment was completed in 58 rats (96.67%). As compared with gastric cancer model group, the general states of rats were improved significantly after treated with different dose Weining granule. Moreover, treatment with different doses of Weining granule could inhibit the protein and mRNA expression of PCNA, pokemon, cyclin D1, Bcl-2, and VEGF, while increase caspase-3 and PTEN (P < 0.01). CONCLUSION: Weining granule could improve gastric cancer by suppressing cell proliferation, promoting tumor cell apoptosis, and inhibiting angiogenesis.