Trametinib Induces the Stabilization of a Dual GNAQ p.Gly48Leu- and FGFR4 p.Cys172Gly-Mutated Uveal Melanoma. The Role of Molecular Modelling in Personalized Oncology

Real-life use of trametinib after immunotherapy failure in BRAF wild-type advanced melanoma

BRAFV600 wild-type advanced melanomas quickly reach a therapeutic dead-end, after immunotherapy failure. Even if preclinical studies have suggested sensitivity to MEK inhibitors such as trametinib in NRAS, NF1 or GNA mutated melanoma, therapeutic options are limited for these patients. We present a retrospective monocentric study of 22 patients with advanced melanoma treated by trametinib after immunotherapy resistance. Melanomas harboured NRAS (20), NF1 (1) or GNA11 (1) mutations. For most of them (18), anti-PD1 was associated with trametinib. A disease-control was reported in 36% of patients (8/22), with six stable diseases and two partial responses according to Response Evaluation Criteria in Solid Tumors (RECIST) criteria. Median progression-free survival was 2 months (1-14) and median overall survival was 6.5 months (2-24). In patients with progressive disease (14/22), dissociated radiologic responses and clinical benefits such as pain reduction were seen in five patients. High blood level of lactate dehydrogenase (LDH) seemed associated with trametinib failure, without significance (P = 0.06). Adverse events (grade 1-3) occurred in 91% of patients during the first weeks of treatment, mainly papulo-pustular rashes (77%), leg oedemas (36%), asthenia (18%) and diarrhoea (14%). This real-life study showed that trametinib may benefit some metastatic melanoma that progressed after chemotherapy and immune checkpoint inhibitors. Objective disease control (partial response or stable disease) using RECIST criteria was observed in 36% of patients. Because of frequent side-effects which can alter the quality of life and the short response duration, this off-label option has to be discussed with the patient. Studies with combination therapy with trametinib to improve relapse-free survival and lower side-effects are ongoing.

GNAQ mutations drive port wine birthmark-associated Sturge-Weber syndrome: A review of pathobiology, therapies, and current models

Port-wine birthmarks (PWBs) are caused by somatic, mosaic mutations in the G protein guanine nucleotide binding protein alpha subunit q (GNAQ) and are characterized by the formation of dilated, dysfunctional blood vessels in the dermis, eyes, and/or brain. Cutaneous PWBs can be treated by current dermatologic therapy, like laser intervention, to lighten the lesions and diminish nodules that occur in the lesion. Involvement of the eyes and/or brain can result in serious complications and this variation is termed Sturge-Weber syndrome (SWS). Some of the biggest hurdles preventing development of new therapeutics are unanswered questions regarding disease biology and lack of models for drug screening. In this review, we discuss the current understanding of GNAQ signaling, the standard of care for patients, overlap with other GNAQ-associated or phenotypically similar diseases, as well as deficiencies in current in vivo and in vitro vascular malformation models.