To investigate the effect of targeting Tie2 by gene therapy on colonic cancer growth and liver metastases.

pLenti-sTie2 was reconstituted to express extracellular soluble fragment of Tie2 in vivo.Ectopic transplant BALB/C mice model with colonic cancer and colonic cancer liver metastases were established using CT26 cell line.The recombinant vectors were injected through the tail vein.Then, tumor volume was measured and serum sTie2 of mice were detected at different time points, respectively.Two weeks later, mice were sacrificed to detect liver metastases and tumor tissues were collected to detect density of blood vessel and apoptosis of tumor cells.

The sTie2 was stably expressed in serum of mice after injection of pLenti-sTie2 and maintained at high level for above 3 weeks [from(1.38±0.19)to(1.52±0.12)g/L]. Compared with Lentivirus, ectopic tumor growth and the metastases formation in the group treated with pLenti-sTie2, was obviously decreased(P<0.05). Pathology detection and DNA ladder detection found that pLenti-sTie2 therapy could obviously inhibit tumor angiogenesis and promote tumor cell apoptosis.

The present study would provide experimental data for targeting Tie2 gene therapy of colonic cancer and liver metastases.