Effect Of Umbilical CD34～+ Cells Transfected With RI Gene For The Growth Of Tumor Cells

Ribonuclease inhibitor (RI) is an acidic cytoplasmic glycoprotein , and it can inhibit the activity of ribonuclease A(RNase A). RI also can inhibit Angiogenin (Ang) strongly. Ang is produced and secreted by tumor cells and normal cells, and it has a robust capacity to induce blood vessel formation in vivo and in vitro. Because RI can form the tight combination with Ang, so it can inhibit the activity of Ang.Many studies demonstrated that angiogensis, the growth of new vessculature, is an essential condition for the development of tumors and their metastatic dissemination. And exogenous restrictions on angiogenesis severely impair tumor growth and sometimes lead to a complete regression. Nowadays, many angiogenetic inhibitors have been found to inhibit angiogenesis in vivo and in vitro experiments. The findings of these specific endothelial inhibitors provide an important therapy method for tumors and other angiogenesis-depend diseases. But one shortage of these inhibitors is that only relatively high concentration can inhibit tumor growth effectively. But the complicated purification process limits their clinical application. Gene therapy can resolve this problem in certain degree. Hematopoietic cells are favorable target cells for gene therapy. Applying hematopoietic cells as carriers of the angiogenetic inhibitor can bring new hope for tumors and other angiogenesis-depend diseases.