Due to their mechanical properties, ranging from flexible to hard materials, polyurethanes (PUs) have been widely used in many industrial and biomedical applications. PUs’ characteristics, along with their biocompatibility, make them successful biomaterials for short and medium-duration applications. The morphology of PUs includes two structural phases: hard and soft segments. Their high mechanical resistance featuresare determined by the hard segment, while the elastomeric behaviour is established by the soft segment. The most important biomedical applications of PUs include antibacterial surfaces and catheters, blood oxygenators, dialysis devices, stents, cardiac valves, vascular prostheses, bioadhesives/surgical dressings/pressure-sensitive adhesives, drug delivery systems, tissue engineering scaffolds and electrospinning, nerve generation, pacemaker lead insulation and coatings for breast implants. The diversity of polyurethane properties, due to the ease of bulk and surface modification, plays a vital role in their applications.

Abstract. Cutaneous malignant melanoma is an aggressive tumor characterized by early lymph node metastasis and bad prognosis. Although the spread of tumor cells in the regionalDespite the latest efforts concerning early detection, both the incidence and mortality caused by malignant melanoma of the skin, continue to grow. Malignant melanoma represents less that 10% of all cutaneous tumors, which is, however, responsible for most deaths caused by tumors of the skin. The natural evolution of malignant melanoma depends on its metastatic dissemination that is, in turn, influenced by multiple factors, particularly the thickness of the tumor, its localization and pathological subtype. Malignant melanomas of the skin are characterized, amongst other things, by early lymphatic dissemination in the regional lymph nodes and by lymph node metastases that significantly influence their staging, prognosis and clinical approach. As a matter of fact, the detection of micrometastases in the sentinel lymph node is of prognostic value and represents the most important predictive criterion for survival in patients with no clinical evidence of lymph node metastases. Moreover, the global survival of patients lacking lymph node metastases is over 85% in a 10-year follow-up and that of patients with positive lymph nodes is less than 45% (1). Once lymph node metastases become clinically obvious, 75-80% of patients already have other distant metastases. It is notable that 15% of the patients diagnosed with thin malignant melanoma (less than 1 mm) develop metastases. At the time being, there are no highly specific predictive indicators for metastases development in patients diagnosed with melanoma.

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A lot of data suggests endocrine gland-derived vascular endothelial growth factor (EG-VEGF) to be restricted to endocrine glands and to some endocrine-dependent organs. Many evidences show that EG-VEGF stimulates angiogenesis and cell proliferation, although it is not a member of the VEGF family. At the time, a lot of data regarding the role of this growth factor in normal development are available. However, controversial results have been published in the case of pathological conditions and particularly in malignant tumors. Thus, our present paper has been focused on the role of EG-VEGF in normal tissues and various malignant tumors and their angiogenic processes.

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