Effects of BRAF Mutations and BRAF Inhibition on Immune Responses to Melanoma
Cet article passe en revue les travaux récents suggérant l'intérêt de combiner une immunothérapie avec des inhibiteurs de BRAF et MEK pour le traitement des patients atteints d'un mélanome présentant un gène BRAF muté
Malignant melanoma is associated with poor clinical prognosis; however, novel molecular and immune therapies are now improving patient outcomes. Almost 50% of melanomas harbor targetable activating mutations of BRAF that promote RAS–RAF–MEK–ERK pathway activation and melanoma proliferation. Recent evidence also indicates that melanomas bearing mutant BRAF may also have altered immune responses, suggesting additional avenues for treatment of this patient group. The small molecule inhibitors selective for mutant BRAF induce significant but short-lived clinical responses in a proportion of patients, but also lead to immune stimulatory bystander events, which then subside with the emergence of resistance to inhibition. Simultaneous BRAF and MEK inhibition, and especially combination of BRAF inhibitors with new immunotherapies such as checkpoint blockade antibodies, may further enhance immune activation, or counteract immunosuppressive signals. Preclinical evaluation and ongoing clinical trials should provide novel insights into the role of immunity in the therapy of BRAF-mutant melanoma.
http://mct.aacrjournals.org/content/early/2014/11/07/1535-7163.MCT-14-0290.abstract 2014