Objective: This study aimed to investigate the effects of Shiquan Dabu Tang (SDT) on growth and angiogenesis of subcutaneously implanted tumors, hepatic metastases, and incision-implanted tumors after surgical removal of primary colon tumor in mice.
Methods: Three experimental models were built after surgical removal of primary colon tumor and the mice were randomly divided into three groups: primary tumor resection (TR) group, primary tumor-preserved (TP) group and SDT group. After resection of the primary tumor and SDT treatment for 10 d, levels of vascular endothelial growth factor (VEGF), angiostatin (AS) and endostatin (ES) were examined by enzyme-linked immunosorbent assay (ELISA); microvascular density (MVD) and cell proliferation of metastasis were detected by streptavidin-peroxidase immunohistochemical staining; tumor cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick-end-labeling (TUNEL) assay.
Results: In the subcutaneously implanted tumor model, the average volume of metastases of the SDT group was significantly lower than that of the TR group (P<0.01); the incidence rate of metastases was 50%. In the hepatic metastases model, the average number of hepatic metastases nodules of the SDT group was significantly lower than that of the TR group (P<0.01); the incidence rate of metastases was 40%. In the incision-implanted tumor model, the average volume of metastases of the SDT group was significantly lower than that of the TR group; the incidence rate of metastases was 30%. MVD was significantly inhibited by SDT and Ki67 expression of the SDT group was significantly lower than that of the TR group (P<0.01). TUNEL apoptotic index of tumor of the SDT group was higher than that of the TR group (P<0.01). ELISA showed that the serum VEGF level was significantly decreased and the serum ES level was significantly increased in the SDT group compared with those in the TR group (P<0.01).
Conclusion: Resection of primary tumor in mice causes imbalance of VEGF, AS and ES, thus promoting angiogenesis and metastasis of tumors. SDT can inhibit growth, angiogenesis and cell proliferation of the metastatic tumor and promote cell apoptosis after surgical removal of the primary tumors.