[Role of angiogenesis in the growth and progression of tumors. Treatment with angiogenesis inhibitors: from promising results in experimental animal models to the reality of clinical use]. / Uloga angiogeneze u rastu i progresiji tumora. Terapija inhibitorima angiogeneze: od obecavajucih rezultata pokusnih zivotinjskih modela do realnosti klinicke primjene.

The development of new blood vessels (angiogenesis) is necessary to sustain the growth of primary tumor as well as a process of tumor metastasis. Cancer cells activate the quiescent vasculature to produce new blood vessels via an "angiogenic switch". Understanding of molecular mechanisms involved in that process is essential for the development of antiangiogenic drugs. Drugs that inhibit angiogenesis could offer a treatment that is complementary to traditional chemotherapy. Chemotherapy directly targets tumor cells, which are prone to develop acquired drug resistance due to genetic instability. Antiangiogenic therapy is directed against endothelial cells in tumor stroma, which are genetically stabile. First results from animal studies supported the theory that endothelial cells do not develop drug resistance and had excellent results in inducing tumor quiescence. However, recent clinical trials showed that antiangiogenic therapy has limitations but that it can improve conventional therapeutic modalities of disseminated disease.