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Simple Summary: Compassionate-use programs provide an opportunity to retrospectively evaluate the treatment patterns and clinical outcomes in a real-world setting to validate the results derived from controlled randomized clinical trials. The COMBI-d and COMBI-v studies established the superior efficacy of dabrafenib + trametinib (dab + tram) versus BRAF inhibitor monotherapy in patients with BRAF V600–mutant metastatic melanoma. In light of their five-year results demonstrating long-term benefit with first-line dab + tram, it is important to get a real-world perspective of the long-term treatment duration for dab + tram. DESCRIBE III was designed to retrospectively evaluate the impact of patient characteristics on the long-term outcomes of dab + tram in a real-world setting based on the duration of clinical benefit. Consistent with the findings from the pooled analysis of COMBI-d and COMBI-v, lower LDH level and <3 metastatic sites at baseline were associated with a longer duration of treatment benefit in a real-world setting. The dabrafenib plus trametinib (dab + tram) combination has demonstrated durable long-term efficacy in patients with BRAF V600–mutant metastatic melanoma. However, real-world data characterizing patients with long-term benefit are limited. DESCRIBE III was a global, observational, retrospective, chart review study in patients with unresectable or metastatic melanoma treated with dab monotherapy and/or dab + tram combination therapy as part of the Named Patient Program or Individual Patient Program. Overall, 509 patients were enrolled. Patients were categorized into three groups based on their observed treatment duration: long-term (on therapy ≥12 months), intermediate (on therapy ≥6 months and <12 months), and short-term (on therapy <6 months) duration of benefit. More patients in the short-term duration of benefit group had baseline characteristics associated with poor prognosis compared with the other two groups. Median lactate dehydrogenase (LDH) levels (368 U/L) at baseline were also higher in the short-term duration of benefit group. No new safety signals were identified. DESCRIBE III identified baseline characteristics associated with long-term benefit of dab + tram. Lower LDH level and <3 metastatic sites at baseline were associated with a longer duration of benefit, confirming that the findings from COMBI-d and COMBI-v are relevant to patients treated in a real-world setting. [ABSTRACT FROM AUTHOR]

Simple Summary: Reflex molecular testing is an emerging concept in oncology that, for a variety of cancers, was demonstrated to reduce the time to treatment initiation, thus potentially impacting survival outcomes. In advanced melanoma, BRAF mutation testing is critical in predicting treatment response with targeted therapy (i.e., BRAF/MEK inhibitors). Certain features were identified in melanomas that harbor BRAF mutations (e.g., primary lesions located on the trunk, diagnosed in patients <50, visibly pigmented tumors and, at times, with ulceration or specific dermatoscopic features). For select advanced melanoma patients, delays in determining mutational status present a significant barrier to the prompt initiation of treatment, which can adversely impact patient outcomes, especially in the metastatic setting due to a rapidly progressive disease. Treatment in these cases needs to start promptly by a medical oncologist. Ordering BRAF testing by preceding members of the treating team will allow medical oncologists to initiate treatment at the first visit. According to poor survival outcomes, we propose that patients with thick tumors (>4.0 mm) or >2 mm tumors with ulceration (i.e., stage ≥IIB) should potentially be considered for systemic therapy, thus justifying reflex BRAF testing. We overview current BRAF mutation testing recommendations and methods used in the United States, Canada, and Europe. Targeted therapy has been developed through an in-depth understanding of molecular pathways involved in the pathogenesis of melanoma. Approximately ~50% of patients with melanoma have tumors that harbor a mutation of the BRAF oncogene. Certain clinical features have been identified in BRAF-mutated melanomas (primary lesions located on the trunk, diagnosed in patients <50, visibly pigmented tumors and, at times, with ulceration or specific dermatoscopic features). While BRAF mutation testing is recommended for stage III–IV melanoma, guidelines differ in recommending mutation testing in stage II melanoma patients. To fully benefit from these treatment options and avoid delays in therapy initiation, advanced melanoma patients harboring a BRAF mutation must be identified accurately and quickly. To achieve this, clear definition and implementation of BRAF reflex testing criteria/methods in melanoma should be established so that patients with advanced melanoma can arrive to their first medical oncology appointment with a known biomarker status. Reflex testing has proven effective for a variety of cancers in selecting therapies and driving other medical decisions. We overview the pathophysiology, clinical presentation of BRAF-mutated melanoma, current guidelines, and present recommendations on BRAF mutation testing. We propose that reflex BRAF testing should be performed for every melanoma patient with stages ≥IIB. [ABSTRACT FROM AUTHOR]

Simple Summary: MEK-inhibitor monotherapy has activity in advanced NRASQ61R/K/L mutant melanoma but is associated with dose-limiting cutaneous toxicity. The combination of a BRAF- with a MEK-inhibitor at their full dose (as in BRAFV600E/K mutant melanoma) has low cutaneous toxicity. We hypothesized that a low dose of the BRAF-inhibitor dabrafenib can mitigate the skin toxicity associated with a full dose of the MEK-inhibitor trametinib in patients with advanced NRASQ61R/K/L mutant melanoma who progressed after treatment with immune checkpoint inhibitors. The results of this two-stage phase 2 trial show that addition of a low dose of dabrafenib effectively mitigates the skin toxicity associated with trametinib. This combination is, however, insufficiently active in patients with advanced NRASQ61R/K/L mutant melanoma. The combination of low-dose dabrafenib plus full-dose trametinib can be of further interest for the treatment of MEK-inhibitor-sensitive tumors. Background: MEK-inhibitor monotherapy has activity in advanced NRASQ61R/K/L mutant melanoma but is associated with dose-limiting cutaneous toxicity. The combination of a BRAF- with a MEK-inhibitor at their full dose (as in BRAFV600E/K mutant melanoma) has low cutaneous toxicity. It is unknown whether a low dose of BRAF-inhibitor can mitigate the skin toxicity associated with full-dose MEK-inhibitor treatment in patients with advanced NRASQ61R/K/L mutant melanoma. Methods: This two-stage phase 2 clinical trial investigated trametinib 2 mg once daily in patients with advanced NRASQ61R/K/L mutant melanoma who were pretreated with immune checkpoint inhibitors. In case of trametinib-related cutaneous toxicity, low-dose dabrafenib (50 mg twice daily) was added to prevent recurrent cutaneous toxicity (pre-amendment). Following an amendment, trametinib was combined upfront with low-dose dabrafenib (post-amendment). Objective response rate (ORR) served as the primary endpoint. Results: All 6 patients enrolled pre-amendment developed trametinib-related cutaneous toxicity, necessitating treatment interruption. Combining trametinib with low-dose dabrafenib prevented recurrent skin toxicity thereafter. Trametinib-related skin toxicity was effectively mitigated in all 10 patients post-amendment. In all 16 included patients, the ORR and disease control rate was 6.3% (1 partial response) and 50.0%, respectively. The trial was halted after the first stage. Conclusions: Combining full-dose trametinib with low-dose dabrafenib can mitigate MEK-inhibitor-related skin toxicity but was insufficiently active in this patient population. This combination can be of further interest for the treatment of MEK-inhibitor-sensitive tumors. [ABSTRACT FROM AUTHOR]

Simple Summary: Brain metastases are common in melanoma and are often associated with significant morbidity and mortality. Although many new treatments for melanoma have been approved in recent years, including immune checkpoint inhibitors and BRAF/MEK inhibitors, limited data are available for survival for patients with brain metastases treated with these novel therapies. The aim of this retrospective study was to evaluate current surgical, radiation, and systemic therapies over the past 10 years in melanoma patients with brain metastases. Our study noted increased overall survival in patients treated with craniotomy and CTLA-4 checkpoint inhibitors, while whole brain radiation was associated with poorer overall survival. Brain metastases commonly develop in melanoma and are associated with poor overall survival of about five to nine months. Fortunately, new therapies, including immune checkpoint inhibitors and BRAF/MEK inhibitors, have been developed. The aim of this study was to identify outcomes of different treatment strategies in patients with melanoma brain metastases in the era of checkpoint inhibitors. Patients with brain metastases secondary to melanoma were identified at a single institution. Univariate and multivariable analyses were performed to identify baseline and treatment factors, which correlated with progression-free and overall survival. A total of 209 patients with melanoma brain metastases were identified. The median overall survival of the cohort was 5.3 months. On multivariable analysis, the presence of non-cranial metastatic disease, poor performance status (ECOG 2–4), whole-brain radiation therapy, and older age at diagnosis of brain metastasis were associated with poorer overall survival. Craniotomy (HR 0.66, 95% CI 0.45–0.97) and treatment with a CTLA-4 checkpoint inhibitor (HR 0.55, 95% CI 0.32–0.94) were the only interventions associated with improved overall survival. Further studies with novel agents are needed to extend lifespan in patients with brain metastases in melanoma. [ABSTRACT FROM AUTHOR]

Simple Summary: Cyclin-dependent kinases 4 and 6 (CDK4/6) are key enzymes controlling the cell cycle. CDK4/6 inhibitors are being tested in multiple clinical trials for a range of cancers including melanoma, and a deeper understanding of how they interact with other therapies is vital for their clinical development. Beyond the cell cycle, CDK4/6 regulates cell metabolism, which is a critical factor determining response to standard-of-care mitogen-activated protein kinase (MAPK) pathway therapies in melanoma. Here, we show that CDK4/6 inhibitors increase glutamine and fatty acid-oxidation-dependent mitochondrial metabolism in melanoma cells, but they do not alter the metabolic response to MAPK inhibitors. These observations shed light on how CDK4/6 inhibitors impinge on the regulation of metabolism and how they interact with other therapies in the setting of melanoma. Cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors are being tested in numerous clinical trials and are currently employed successfully in the clinic for the treatment of breast cancers. Understanding their mechanism of action and interaction with other therapies is vital in their clinical development. CDK4/6 regulate the cell cycle via phosphorylation and inhibition of the tumour suppressor RB, and in addition can phosphorylate many cellular proteins and modulate numerous cellular functions including cell metabolism. Metabolic reprogramming is observed in melanoma following standard-of-care BRAF/MEK inhibition and is involved in both therapeutic response and resistance. In preclinical models, CDK4/6 inhibitors overcome BRAF/MEK inhibitor resistance, leading to sustained tumour regression; however, the metabolic response to this combination has not been explored. Here, we investigate how CDK4/6 inhibition reprograms metabolism and if this alters metabolic reprogramming observed upon BRAF/MEK inhibition. Although CDK4/6 inhibition has no substantial effect on the metabolic phenotype following BRAF/MEK targeted therapy in melanoma, CDK4/6 inhibition alone significantly enhances mitochondrial metabolism. The increase in mitochondrial metabolism in melanoma cells following CDK4/6 inhibition is fuelled in part by both glutamine metabolism and fatty acid oxidation pathways and is partially dependent on p53. Collectively, our findings identify new p53-dependent metabolic vulnerabilities that may be targeted to improve response to CDK4/6 inhibitors. [ABSTRACT FROM AUTHOR]

Purpose: To explore the genetic background of choroidal and ciliary body melanoma among children and young adults, with special focus on BAP1 germline variants in this age group., Methods: Patients under the age of 25 and with confirmed choroidal or ciliary body melanoma were included in this retrospective, multicenter observational study. Nuclear BAP1 immunopositivity was used to evaluate the presence of functional BAP1 in the tumor. Next-generation sequencing using Ion Torrent platform was used to determine pathogenic variants of BAP1, EIF1AX, SF3B1, GNAQ and GNA11 and chromosome 3 status in the tumor or in DNA extracted from blood or saliva. Survival was analyzed using Kaplan-Meier estimates., Results: The mean age at diagnosis was 17 years (range 5.0-24.8). A germline BAP1 pathogenic variant was identified in an 18-year-old patient, and a somatic variant, based mainly on immunohistochemistry, in 13 (42%) of 31 available specimens. One tumor had a somatic SF3B1 pathogenic variant. Disomy 3 and the absence of a BAP1 pathogenic variant in the tumor predicted the longest metastasis-free survival. Males showed longer metastasis-free survival than females (P = 0.018)., Conclusions: We did not find a stronger-than-average BAP1 germline predisposition for choroidal and ciliary body melanoma among children and young adults compared to adults. Males had a more favorable survival and disomy 3, and the absence of a BAP1 mutation in the tumor tissue predicted the most favorable metastasis-free survival. A BAP1 germline pathogenic variant was identified in one patient (1%), and a somatic variant based mainly on immunohistochemistry in 13 (42%).

Aims: To report long-term results of intracameral chemotherapy (ICC) for aqueous seeding (AS) in retinoblastoma., Methods: Retrospective study including 20 patients with primary (n=4) or secondary non-iatrogenic (n=16) AS treated with ICC according to a previously described technique between 2011 and 2020 with at least 1-year follow-up., Results: AS control was initially achieved in all cases with a mean 5 injections of melphalan (n=13) or topotecan (n=7). Three eyes had an isolated AS relapse at a mean interval of 8 months after the first ICC course, which regressed with a second course of intracameral melphalan. Concomitant interciliary process seed implantation was treated with additional brachytherapy if sectorial (n=3) or proton therapy if annular (n=1). Other therapies including systemic, intra-arterial chemotherapy and/or focal treatments were given in 15 eyes to treat concomitant tumour sites. Eye preservation was achieved in 85% of the eyes (n=17/20) at a mean event-free follow-up of 45 months for aqueous disease, and 40 months for any other intraocular tumour activity. Three cases were enucleated due to refractory non-aqueous disease. All patients are alive without metastasis (mean follow-up of 48 months after first ICC). ICC-related intraocular toxicity included iris atrophy (n=5), cataract (n=4), posterior synechiae (n=2) and iris heterochromia (n=1). No patient suffered irreversible vision loss. Useful to normal vision was found in 82% of the cases (n=14/17)., Conclusion: ICC appears to be safe and efficient for AS without irreversible vision-threatening adverse effects. More data are needed to determine any superiority in efficiency/toxicity of topotecan versus melphalan., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: The exact cellular types that form the human fovea remain a subject of debate, and few studies have been conducted on human macula to solve this question. The purpose of this study was to perform immunohistochemistry on fresh human samples to characterize the glial cells that form the human fovea., Methods: Immunohistochemistry was performed using antibodies against proteins expressed in astrocytes or in retinal Müller glial cells or both types of cells on six human macula obtained from eyes enucleated for peripheral intraocular tumors and on two postmortem eyes from healthy donors. The posterior poles of the enucleated eyes were cryosectioned and stained with antibodies against the glial proteins GFAP, vimentin, CRALBP, glutamine synthetase, and connexin 43., Results: A population of cells positive for GFAP and negative for glutamine synthetase and CRALBP that express connexin 43 were identified at the roof of the foveal pit. These cells are distinct from the Müller cone cells described by Yamada and Gass, suggesting that another type of foveal glial cells, most likely astrocytes, are present in the human fovea., Conclusions: This study showed that in humans, astrocytic glial cells cover the foveal pit. Their roles in macula homeostasis and mechanisms of macular diseases disease remain to be determined., (Copyright © 2020 Molecular Vision.)

In diabetic retinopathy, the exact mechanisms leading to retinal capillary closure and to retinal barriers breakdown remain imperfectly understood. Rho-associated kinase (ROCK), an effector of the small GTPase Rho, involved in cytoskeleton dynamic regulation and cell polarity is activated by hyperglycemia. In one year-old Goto Kakizaki (GK) type 2 diabetic rats retina, ROCK-1 activation was assessed by its cellular distribution and by phosphorylation of its substrates, MYPT1 and MLC. In both GK rat and in human type 2 diabetic retinas, ROCK-1 is activated and associated with non-apoptotic membrane blebbing in retinal vessels and in retinal pigment epithelium (RPE) that respectively form the inner and the outer barriers. Activation of ROCK-1 induces focal vascular constrictions, endoluminal blebbing and subsequent retinal hypoxia. In RPE cells, actin cytoskeleton remodeling and membrane blebs in RPE cells contributes to outer barrier breakdown. Intraocular injection of fasudil, significantly reduces both retinal hypoxia and RPE barrier breakdown. Diabetes-induced cell blebbing may contribute to ischemic maculopathy and represent an intervention target.