Simple Summary Uveal melanoma is a rare and aggressive disease. G alpha-proteins GNAQ and GNA11 are driver mutations that activate MAP kinase and YAP/TAZ pathways. BAP1 loss and monosomy of... Show moreSimple Summary Uveal melanoma is a rare and aggressive disease. G alpha-proteins GNAQ and GNA11 are driver mutations that activate MAP kinase and YAP/TAZ pathways. BAP1 loss and monosomy of chromosome 3 are present in patients with high risk of metastasis. MEK-inhibitors do not significantly block UM progression. Combinations of the MEK inhibitor trametinib and different classes of drugs targeting YAP/TAZ were used to overcome resistance. Combination of trametinib and cerivastatin were synergistic in vitro and in vivo in BAP1 mutated and chromosome 3 monosomic uveal melanoma cell lines. Background: Metastatic uveal melanoma (MUM) is a highly aggressive, therapy-resistant disease. Driver mutations in G alpha-proteins GNAQ and GNA11 activate MAP-kinase and YAP/TAZ pathways of oncogenic signalling. MAP-kinase and MEK-inhibitors do not significantly block MUM progression, likely due to persisting YAP/TAZ signalling. Statins inhibit YAP/TAZ activation by blocking the mevalonate pathway, geranyl-geranylation, and subcellular localisation of the Rho-GTPase. We investigated drugs that affect the YAP/TAZ pathway, valproic acid, verteporfin and statins, in combination with MEK-inhibitor trametinib. Methods: We established IC50 values of the individual drugs and monitored the effects of their combinations in terms of proliferation. We selected trametinib and cerivastatin for evaluation of cell cycle and apoptosis. Synergism was detected using isobologram and Chou-Talalay analyses. The most synergistic combination was tested in vivo. Results: Synergistic concentrations of trametinib and cerivastatin induced a massive arrest of proliferation and cell cycle and enhanced apoptosis, particularly in the monosomic, BAP1-mutated UPMM3 cell line. The combined treatment reduced ERK and AKT phosphorylation, increased the inactive, cytoplasmatic form of YAP and significantly impaired the growth of UM cells with monosomy of chromosome 3 in NSG mice. Conclusion: Statins can potentiate the efficacy of MEK inhibitors in the therapy of UM. Show less
Spagnolo, F.; Dalmasso, B.; Tanda, E.; Potrony, M.; Puig, S.; Doorn, R. van; ... ; Ghiorzo, P. 2021
Simple Summary In our study, we retrospectively collected data of patients with germline CDKN2A pathogenic variants who received targeted therapy for advanced melanoma across four European centers.... Show moreSimple Summary In our study, we retrospectively collected data of patients with germline CDKN2A pathogenic variants who received targeted therapy for advanced melanoma across four European centers. Since loss of CDKN2A function may intrinsically limit the activity of MAPK-directed targeted therapy, we decided to assess whether patients with germline CDKN2A pathogenic variants may achieve suboptimal results with BRAF and MEK inhibitors. To the best of our knowledge, this is the first study reporting on patients with BRAF-mutant advanced melanoma and a germline CDKN2A pathogenic variant who received treatment with BRAF with or without MEK inhibitors. Despite the limitations of our study, mostly due to the rare frequency of CDKN2A pathogenic variants, a challenge for the conduction of prospective trials with proper sample size, our results support treatment with targeted therapy in this subset of patients.Inherited pathogenic variants (PVs) in the CDKN2A tumor suppressor gene are among the strongest risk factors for cutaneous melanoma. Dysregulation of the p16/RB1 pathway may intrinsically limit the activity of MAPK-directed therapy due to the interplay between the two pathways. In our study, we assessed, for the first time, whether patients with germline CDKN2A PVs achieve suboptimal results with BRAF inhibitors (BRAFi)+/-MEK inhibitors (MEKi). We compared the response rate of nineteen CDKN2A PVs carriers who received first-line treatment with BRAFi+/-MEKi with an expected rate derived from phase III trials and "real-world" studies. We observed partial response in 16/19 patients (84%), and no complete responses. The overall response rate was higher than that expected from phase III trials (66%), although not statistically significant (p-value = 0.143; 95% CI = 0.60-0.97); the difference was statistically significant (p-value = 0.019; 95% CI = 0.62-0.97) in the comparison with real-world studies (57%). The clinical activity of BRAFi+/-MEKi in patients with germline CDKN2A PV was not inferior to that of clinical trials and real-world studies, which is of primary importance for clinical management and genetic counseling of this subgroup of patients. Show less
Gangemi, R.; Amaro, A.; Gino, A.; Barisione, G.; Fabbi, M.; Pfeffer, U.; ... ; Ferrini, S. 2014
