1. Immunomodulatory effects of BRAF and MEK inhibitors: Implications for Melanoma therapy
- Author
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Marc Schmitz, Dana Westphal, Marvin Kuske, Friedegund Meier, Rebekka Wehner, Christian Praetorius, and Stefan Beissert
- Subjects
Proto-Oncogene Proteins B-raf ,0301 basic medicine ,T-Lymphocytes ,medicine.medical_treatment ,Antineoplastic Agents ,Targeted therapy ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,In vivo ,medicine ,Animals ,Humans ,Immunologic Factors ,In patient ,Molecular Targeted Therapy ,Melanoma ,Protein Kinase Inhibitors ,Mitogen-Activated Protein Kinase Kinases ,Pharmacology ,Tumor microenvironment ,Immune effector ,business.industry ,Immunotherapy ,medicine.disease ,030104 developmental biology ,030220 oncology & carcinogenesis ,Cancer research ,Drug Therapy, Combination ,business - Abstract
Targeted therapy with BRAF inhibitors (BRAFi) and MEK inhibitors (MEKi) provides rapid disease control with high response rates in patients with BRAF-mutant metastatic melanoma. However, the majority of patients develop resistance to therapy during the course of therapy. Immune checkpoint inhibitors show a slower onset of action with lower response rates, with responders showing sustained response. The combination of BRAFi/MEKi and immune checkpoint inhibitors combines the hope for a fast, reliable and lasting response to therapy. Preclinical data supports this hypothesis. With the help of the PubMed database, a comprehensive search and analysis of preclinical and clinical studies on the combination of BRAFi/MEKi with immune checkpoint inhibitors was performed and yielded the following results: 1) In vivo, BRAFi and MEKi have no negative effects on immune cells; BRAFi and MEKi generate 2) an immune stimulating tumor microenvironment, 3) an increased infiltration of immune cells into the tumors, 4) a better recognition of melanoma cells by immune effector cells, and 5) a better functionality of the immune effector cells. In addition, in vivo experiments 6) demonstrated a superiority of the combination treatment compared to the individual strategies in both BRAF-mutant and BRAF wild-type melanomas. In summary, available data show that both BRAFi and MEKi have beneficial effects on the antitumor immunity and the tumor microenvironment as a whole, which is mediated by different mechanisms. Currently, clinical studies are underway to investigate combinations of BRAFi and MEKi with immune checkpoint inhibitors. The results of these studies are eagerly awaited.
- Published
- 2018