RESUMO
The incidence of cutaneous melanoma has risen at a rate significantly higher than that for other malignancies. This increase persists despite efforts to educate the public about the dangers of excess exposure to UV radiation from both the sun and tanning beds. Melanoma affects a relatively younger population and is notorious for its propensity to metastasize and for its poor response to current therapeutic regimens. These factors make prevention an integral component to the goal of decreasing melanoma-related mortality. Transformation of melanocytes into malignant melanoma involves the interplay between genetic factors, UV exposure, and the tumor microenvironment. The roles of UV radiation in the etiology of melanoma are mediated by both direct damage of DNA through formation of photoproducts and production of reactive oxygen species (ROS). Many of the promising antioxidant agents under development for the prevention of melanoma are derived from foodstuffs. B-Raf is a member of the Raf kinase family of serine/threonine-specific protein kinases that plays a role in regulating the MAP kinase/ERKs signaling pathway. About 50 % of melanomas harbor activating BRAF mutations. BRAF mutations are found in 59 % of the melanomas arising in skin with intermittent sun exposure, such as trunk and arms, as compared with only 23 % of the acral melanomas, 11 % of mucosal melanomas, and 0 % of uveal melanomas. Two new agents, ipilimumab and vemurafenib, have been shown to improve outcome of advanced melanoma as presented at the plenary session of the 2011 annual meeting of the American Society of Clinical Oncology. Vemurafenib is the first personalized compound which demonstrated an improvement in progression-free survival (PFS) and overall survival (OS) in metastatic melanoma harboring the BRAFV600 mutation and represents the first drug of a class that exerts its anti-proliferative activity through inhibition of a highly specific molecular target. GSK2118436 (dabrafenib), the second BRAF inhibitor, in phase I and II trial obtained similar results to vemurafenib. A phase III trial is now ongoing. Taken together, the early clinical development of vemurafenib and dabrafenib clearly confirms that BRAF inhibitors can halt or reverse disease in patients with melanomas carrying this mutation, improving survival times compared with historically standard treatments (chemotherapy and interleukin-2). The clinical development of other new BRAF inhibitors such as RAF265 and LGX818 is now ongoing. Combination strategies of BRAF inhibitors with ipilimumab, an anti-CTLA-4 antibody, and/or MEK inhibitors or metformin are now under investigation in clinical trials.
Assuntos
Antineoplásicos/uso terapêutico , Melanoma/prevenção & controle , Terapia de Alvo Molecular , Animais , Humanos , Melanoma/metabolismoRESUMO
After more than 30 years, landmark progress has been made in the treatment of cancer, and melanoma in particular, with the success of new molecules such as ipilimumab, vemurafenib and active specific immunization.After the first congress in December 2010, the second edition of "Melanoma Research: a bridge from Naples to the World" meeting, organized by Paolo A. Ascierto (INT, Naples, Italy), Francesco M. Marincola (NIH, Bethesda, USA), and Nicola Mozzillo (INT, Naples, Italy) took place in Naples, on 5-6 December 2011. We have identified four new topics of discussion: Innovative Approaches in Prevention, Diagnosis and Surgical Treatment, New Pathways and Targets in Melanoma: An Update about Immunotherapy, and Combination Strategies. This international congress gathered more than 30 international faculty members and was focused on recent advances in melanoma molecular biology, immunology and therapy, and created an interactive atmosphere which stimulated discussion of new approaches and strategies in the field of melanoma.