THE ROLE OF TUMOR-ASSOCIATED MACROPHAGES ON MICROVESSEL DENSITY AFTER NEOADJUVANT CHEMOTHERAPY IN TONGUE CANCER

Preoperative neoadjuvant chemotherapy using cisplatin and 5-FU is generally given in oral and maxillofacial cancer. At tissue level both inflammation and fibrosis occur after chemotherapy. The cellular changes mimic those of a granulating wound, with activated macrophages and fibroblasts replacing the malignant cells as they are erradicated. Stromal cells, together with extracellular matrix components, provide the microenvironment that is pivotal for tumor cell growth, invasion, and metastatic progression. Vascular endothelial growth factor( VEGF), an important regulator of angiogenesis in cancer, induces mitogenesis of vascular endothelial cells, and vascular permeabilization and microvessel formation in a tumor are associated with tumor nutrition and oxygenation. Also, they are associated with chemotherapeutic drug delivery. Oxygen delivery to tumor appears to rely on a network of microvessels, On the other hand, the tumor microvessel is clearly an important factor in chemotherapeutic drug delivery to cancer cells, and the efficacy of drug delivery can be high in richly vascularized tumors. So, this study was conducted to evaluate the effect of neoadjuvant chemotherapy on microvessel density from 11 patients with tongue cancers. Our results showed that neoadjuvant chemotherapy was seemed to decrease VEGF expression in tumor cells, however, it did not significantly alter VEGF expression in tumor-associated macrophages. Also, Neoadjuvant chemotherapy had little effect on the microvessel density using CD34, and tumor-associated macrophage level using CD68. Thus, tumorassociated macrophages seem to be the key factor associated with the maintenance of microvessel density after neoadjuvant chemotherapy in tongue cancer.