The effects of anti-angiogenic
therapies in guiding
tumor angioarchitecture prompted us to examine the modifications in the vascular network of the
oral squamous cell carcinoma (SCC) produced by the multitargeted
tyrosine kinase inhibitor sunitinib malate. Twelve Syrian hamsters had their right buccal pouches submitted to
tumor induction with dimethylbenzanthracene and
carbamide peroxide for 55 days. The animals were then divided into two groups of six animals each; group I was treated with
sunitinib malate and group II (control) was remained untreated. After 4 weeks, the hamsters had their vascular networks casted by Mercox® resin and analyzed by scanning electron microscopy. The qualitative study of the vascular network of the control
tumor-bearing pouches showed images of
intussusception and sprouting angiogenesis, flattened blood vessels, abrupt variations in their diameter, and a tortuous course. The samples treated with
sunitinib exhibited a qualitative reduction of the signs of vascular proliferation. In addition, these casts presented an attenuation of the morphological features observed in the untreated
tumor-bearing pouches. Quantitative analysis demonstrated that the pouches treated with
sunitinib did not show a decrease (P > 0.05) in the vascular diameter and intervessel distances when compared with the control group. The results of the present study suggest that
sunitinib may act on the vascular network of oral SCC, normalizing the blood vessels. However, further experiments should be performed in order to determine a judicious dose of this anti-angiogenic
therapy.