RESUMO
BACKGROUND: Aberrant PI3K/AKT signaling in BRAF-mutant cancers contributes to resistance to BRAF inhibitors. The authors examined dual MAPK and PI3K pathway inhibition in patients who had BRAF-mutated solid tumors (ClinicalTrials.gov identifier NCT01902173). METHODS: Patients with BRAF V600E/V600K-mutant solid tumors received oral dabrafenib at 150 mg twice daily with dose escalation of oral uprosertib starting at 50 mg daily, or, in the triplet cohorts, with dose escalation of both oral trametinib starting at 1.5 mg daily and oral uprosertib starting at 25 mg daily. Dose-limiting toxicities (DLTs) were assessed within the first 56 days of treatment. Radiographic responses were assessed at 8-week intervals. RESULTS: Twenty-seven patients (22 evaluable) were enrolled in parallel doublet and triplet cohorts. No DLTs were observed in the doublet cohorts (N = 7). One patient had a DLT at the maximum administered dose of triplet therapy (dabrafenib 150 mg twice daily and trametinib 2 mg daily plus uprosertib 75 mg daily). Three patients in the doublet cohorts had partial responses (including one who had BRAF inhibitor-resistant melanoma). Two patients in the triplet cohorts had a partial response, and one patient had an unconfirmed partial response. Pharmacokinetic data suggested reduced dabrafenib and dabrafenib metabolite exposure in patients who were also exposed to both trametinib and uprosertib, but not in whose who were exposed to uprosertib without trametinib. CONCLUSIONS: Concomitant inhibition of both the MAPK and PI3K-AKT pathways for the treatment of BRAF-mutated cancers was well tolerated, leading to objective responses, but higher level drug-drug interactions affected exposure to dabrafenib and its metabolites.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Imidazóis , Mutação , Neoplasias , Oximas , Inibidores de Proteínas Quinases , Proteínas Proto-Oncogênicas B-raf , Proteínas Proto-Oncogênicas c-akt , Piridonas , Pirimidinonas , Humanos , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Adulto , Piridonas/administração & dosagem , Piridonas/efeitos adversos , Pirimidinonas/administração & dosagem , Pirimidinonas/efeitos adversos , Pirimidinonas/uso terapêutico , Imidazóis/administração & dosagem , Imidazóis/uso terapêutico , Imidazóis/efeitos adversos , Imidazóis/farmacocinética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Oximas/administração & dosagem , Oximas/efeitos adversos , Oximas/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/uso terapêutico , Idoso de 80 Anos ou mais , Terapia de Alvo MolecularRESUMO
Outcomes for patients with melanoma have improved over the past decade with the clinical development and approval of immunotherapies targeting immune checkpoint receptors such as programmed death-1 (PD-1), programmed death ligand 1 (PD-L1) or cytotoxic T lymphocyte antigen-4 (CTLA-4). Combinations of these checkpoint therapies with other agents are now being explored to improve outcomes and enhance benefit-risk profiles of treatment. Alternative inhibitory receptors have been identified that may be targeted for anti-tumor immune therapy, such as lymphocyte-activation gene-3 (LAG-3), as have several potential target oncogenes for molecularly targeted therapy, such as tyrosine kinase inhibitors. Unfortunately, many patients still progress and acquire resistance to immunotherapy and molecularly targeted therapies. To bypass resistance, combination treatment with immunotherapies and single or multiple TKIs have been shown to improve prognosis compared to monotherapy. The number of new combinations treatment under development for melanoma provides options for the number of patients to achieve a therapeutic benefit. Many diagnostic and prognostic assays have begun to show clinical applicability providing additional tools to optimize and individualize treatments. However, the question on the optimal algorithm of first- and later-line therapies and the search for biomarkers to guide these decisions are still under investigation. This year, the Melanoma Bridge Congress (Dec 1st-3rd, 2022, Naples, Italy) addressed the latest advances in melanoma research, focusing on themes of paramount importance for melanoma prevention, diagnosis and treatment. This included sessions dedicated to systems biology on immunotherapy, immunogenicity and gene expression profiling, biomarkers, and combination treatment strategies.
Assuntos
Melanoma , Humanos , Melanoma/terapia , Melanoma/tratamento farmacológico , Imunoterapia , Antígeno CTLA-4 , ItáliaRESUMO
Metastasis and failure of present-day therapies represent the most common causes of mortality in patients with cutaneous melanoma. To identify the underlying genetic and transcriptomic landscapes, in this study we analyzed multi-organ metastases and tumor-adjacent tissues from 11 rapid autopsies after treatment with MAPK inhibitor (MAPKi) and/or immune checkpoint blockade (ICB) and death due to acquired resistance. Either treatment elicits shared genetic alterations that suggest immune-evasive, cross-therapy resistance mechanisms. Large, non-clustered deletions, inversions and inter-chromosomal translocations dominate rearrangements. Analyzing data from separate melanoma cohorts including 345 therapy-naive patients and 35 patients with patient-matched pre-treatment and post-acquired resistance tumor samples, we performed cross-cohort analyses to identify MAPKi and ICB as respective contributors to gene amplifications and deletions enriched in autopsy versus therapy-naive tumors. In the autopsy cohort, private/late mutations and structural variants display shifted mutational and rearrangement signatures, with MAPKi specifically selecting for signatures of defective homologous-recombination, mismatch and base-excision repair. Transcriptomic signatures and crosstalks with tumor-adjacent macroenvironments nominated organ-specific adaptive pathways. An immune-desert, CD8+-macrophage-biased archetype, T-cell exhaustion and type-2 immunity characterized the immune contexture. This multi-organ analysis of therapy-resistant melanoma presents preliminary insights with potential to improve therapeutic strategies.
Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Resistencia a Medicamentos Antineoplásicos/genética , Transcriptoma/genética , Perfilação da Expressão GênicaRESUMO
Blocking cancer genomic instability may prevent tumor diversification and escape from therapies. We show that, after MAPK inhibitor (MAPKi) therapy in patients and mice bearing patient-derived xenografts (PDX), acquired resistant genomes of metastatic cutaneous melanoma specifically amplify resistance-driver, nonhomologous end-joining (NHEJ), and homologous recombination repair (HRR) genes via complex genomic rearrangements (CGR) and extrachromosomal DNAs (ecDNA). Almost all sensitive and acquired-resistant genomes harbor pervasive chromothriptic regions with disproportionately high mutational burdens and significant overlaps with ecDNA and CGR spans. Recurrently, somatic mutations within ecDNA and CGR amplicons enrich for HRR signatures, particularly within acquired resistant tumors. Regardless of sensitivity or resistance, breakpoint-junctional sequence analysis suggests NHEJ as critical to double-stranded DNA break repair underlying CGR and ecDNA formation. In human melanoma cell lines and PDXs, NHEJ targeting by a DNA-PKCS inhibitor prevents/delays acquired MAPKi resistance by reducing the size of ecDNAs and CGRs early on combination treatment. Thus, targeting the causes of genomic instability prevents acquired resistance. SIGNIFICANCE: Acquired resistance often results in heterogeneous, redundant survival mechanisms, which challenge strategies aimed at reversing resistance. Acquired-resistant melanomas recurrently evolve resistance-driving and resistance-specific amplicons via ecDNAs and CGRs, thereby nominating chromothripsis-ecDNA-CGR biogenesis as a resistance-preventive target. Specifically, targeting DNA-PKCS/NHEJ prevents resistance by suppressing ecDNA/CGR rearrangements in MAPKi-treated melanomas. This article is highlighted in the In This Issue feature, p. 799.
Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Animais , Camundongos , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/metabolismo , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Linhagem Celular , Instabilidade Genômica , DNARESUMO
Extrachromosomal DNA (ecDNA) is a common mode of oncogene amplification but is challenging to analyze. Here, we adapt CRISPR-CATCH, in vitro CRISPR-Cas9 treatment and pulsed field gel electrophoresis of agarose-entrapped genomic DNA, previously developed for bacterial chromosome segments, to isolate megabase-sized human ecDNAs. We demonstrate strong enrichment of ecDNA molecules containing EGFR, FGFR2 and MYC from human cancer cells and NRAS ecDNA from human metastatic melanoma with acquired therapeutic resistance. Targeted enrichment of ecDNA versus chromosomal DNA enabled phasing of genetic variants, identified the presence of an EGFRvIII mutation exclusively on ecDNAs and supported an excision model of ecDNA genesis in a glioblastoma model. CRISPR-CATCH followed by nanopore sequencing enabled single-molecule ecDNA methylation profiling and revealed hypomethylation of the EGFR promoter on ecDNAs. We distinguished heterogeneous ecDNA species within the same sample by size and sequence with base-pair resolution and discovered functionally specialized ecDNAs that amplify select enhancers or oncogene-coding sequences.
Assuntos
Glioblastoma , Neoplasias , Humanos , Oncogenes , DNA/genética , Neoplasias/genética , Neoplasias/patologia , Glioblastoma/genética , Receptores ErbB/genéticaRESUMO
Advances in immune checkpoint and combination therapy have led to improvement in overall survival for patients with advanced melanoma. Improved understanding of the tumor, tumor microenvironment and tumor immune-evasion mechanisms has resulted in new approaches to targeting and harnessing the host immune response. Combination modalities with other immunotherapy agents, chemotherapy, radiotherapy, electrochemotherapy are also being explored to overcome resistance and to potentiate the immune response. In addition, novel approaches such as adoptive cell therapy, oncogenic viruses, vaccines and different strategies of drug administration including sequential, or combination treatment are being tested. Despite the progress in diagnosis of melanocytic lesions, correct classification of patients, selection of appropriate adjuvant and systemic theràapies, and prediction of response to therapy remain real challenges in melanoma. Improved understanding of the tumor microenvironment, tumor immunity and response to therapy has prompted extensive translational and clinical research in melanoma. There is a growing evidence that genomic and immune features of pre-treatment tumor biopsies may correlate with response in patients with melanoma and other cancers, but they have yet to be fully characterized and implemented clinically. Development of novel biomarker platforms may help to improve diagnostics and predictive accuracy for selection of patients for specific treatment. Overall, the future research efforts in melanoma therapeutics and translational research should focus on several aspects including: (a) developing robust biomarkers to predict efficacy of therapeutic modalities to guide clinical decision-making and optimize treatment regimens, (b) identifying mechanisms of therapeutic resistance to immune checkpoint inhibitors that are potentially actionable, (c) identifying biomarkers to predict therapy-induced adverse events, and (d) studying mechanism of actions of therapeutic agents and developing algorithms to optimize combination treatments. During the Melanoma Bridge meeting (December 2nd-4th, 2021, Naples, Italy) discussions focused on the currently approved systemic and local therapies for advanced melanoma and discussed novel biomarker strategies and advances in precision medicine as well as the impact of COVID-19 pandemic on management of melanoma patients.
Assuntos
COVID-19 , Melanoma , Biomarcadores , Humanos , Imunoterapia/métodos , Itália , Melanoma/genética , Pandemias , Microambiente TumoralRESUMO
MAPK inhibitor (MAPKi) therapy in melanoma leads to the accumulation of tumor-surface PD-L1/L2, which may evade antitumor immunity and accelerate acquired resistance. Here, we discover that the E3 ligase ITCH binds, ubiquitinates, and downregulates tumor-surface PD-L1/L2 in MAPKi-treated human melanoma cells, thereby promoting T-cell activation. During MAPKi therapy in vivo, melanoma cell-intrinsic ITCH knockdown induced tumor-surface PD-L1, reduced intratumoral cytolytic CD8+ T cells, and accelerated acquired resistance only in immune-competent mice. Conversely, tumor cell-intrinsic ITCH overexpression reduced MAPKi-elicited PD-L1 accumulation, augmented intratumoral cytolytic CD8+ T cells, and suppressed acquired resistance in BrafV600MUT, NrasMUT, or Nf1MUT melanoma and KrasMUT-driven cancers. CD8+ T-cell depletion and tumor cell-intrinsic PD-L1 overexpression nullified the phenotype of ITCH overexpression, thereby supporting an in vivo ITCH-PD-L1-T-cell regulatory axis. Moreover, we identify a small-molecular ITCH activator that suppresses acquired MAPKi resistance in vivo. Thus, MAPKi-induced PD-L1 accelerates resistance, and a PD-L1-degrading ITCH activator prolongs antitumor response. SIGNIFICANCE: MAPKi induces tumor cell-surface PD-L1 accumulation, which promotes immune evasion and therapy resistance. ITCH degrades PD-L1, optimizing antitumor T-cell immunity. We propose degrading tumor cell-surface PD-L1 and/or activating tumor-intrinsic ITCH as strategies to overcome MAPKi resistance. This article is highlighted in the In This Issue feature, p. 1825.
Assuntos
Antígeno B7-H1 , Melanoma , Proteínas Quinases Ativadas por Mitógeno , Proteínas Repressoras , Ubiquitina-Proteína Ligases , Animais , Linfócitos T CD8-Positivos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Melanoma/genética , Camundongos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Repressoras/genética , Ubiquitina-Proteína Ligases/genéticaRESUMO
Focal amplifications (FA) can mediate targeted therapy resistance in cancer. Understanding the structure and dynamics of FAs is critical for designing treatments that overcome plasticity-mediated resistance. We developed a melanoma model of dual MAPK inhibitor (MAPKi) resistance that bears BRAFV600 amplifications through either extrachromosomal DNA (ecDNA)/double minutes (DM) or intrachromosomal homogenously staining regions (HSR). Cells harboring BRAFV600E FAs displayed mode switching between DMs and HSRs, from both de novo genetic changes and selection of preexisting subpopulations. Plasticity is not exclusive to ecDNAs, as cells harboring HSRs exhibit drug addiction-driven structural loss of BRAF amplicons upon dose reduction. FA mechanisms can couple with kinase domain duplications and alternative splicing to enhance resistance. Drug-responsive amplicon plasticity is observed in the clinic and can involve other MAPK pathway genes, such as RAF1 and NRAS. BRAF FA-mediated dual MAPKi-resistant cells are more sensitive to proferroptotic drugs, extending the spectrum of ferroptosis sensitivity in MAPKi resistance beyond cases of dedifferentiation. SIGNIFICANCE: Understanding the structure and dynamics of oncogene amplifications is critical for overcoming tumor relapse. BRAF amplifications are highly plastic under MAPKi dosage challenges in melanoma, through involvement of de novo genomic alterations, even in the HSR mode. Moreover, BRAF FA-driven, dual MAPKi-resistant cells extend the spectrum of resistance-linked ferroptosis sensitivity. This article is highlighted in the In This Issue feature, p. 873.
Assuntos
Melanoma , Proteínas Proto-Oncogênicas B-raf , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , Mutação , Recidiva Local de Neoplasia/tratamento farmacológico , Oncogenes , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismoRESUMO
Neoadjuvant PD-1 blockade may be efficacious in some individuals with high-risk, resectable oral cavity head and neck cancer. To explore correlates of response patterns to neoadjuvant nivolumab treatment and post-surgical recurrences, we analyzed longitudinal tumor and blood samples in a cohort of 12 individuals displaying 33% responsiveness. Pretreatment tumor-based detection of FLT4 mutations and PTEN signature enrichment favors response, and high tumor mutational burden improves recurrence-free survival. In contrast, preexisting and/or acquired mutations (in CDKN2A, YAP1, or JAK2) correlate with innate resistance and/or tumor recurrence. Immunologically, tumor response after therapy entails T cell receptor repertoire diversification in peripheral blood and intratumoral expansion of preexisting T cell clones. A high ratio of regulatory T to T helper 17 cells in pretreatment blood predicts low T cell receptor repertoire diversity in pretreatment blood, a low cytolytic T cell signature in pretreatment tumors, and innate resistance. Our study provides a molecular framework to advance neoadjuvant anti-PD-1 therapy for individuals with resectable head and neck cancer.
Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias Bucais/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Nivolumabe/uso terapêutico , Receptor de Morte Celular Programada 1/genética , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/genética , Antineoplásicos Imunológicos/uso terapêutico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/cirurgia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/imunologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Janus Quinase 2/genética , Janus Quinase 2/imunologia , Neoplasias Bucais/genética , Neoplasias Bucais/imunologia , Neoplasias Bucais/cirurgia , Mutação , Terapia Neoadjuvante/métodos , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/cirurgia , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Análise de Sobrevida , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Células Th17/patologia , Resultado do Tratamento , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/imunologia , Proteínas de Sinalização YAP/genética , Proteínas de Sinalização YAP/imunologiaRESUMO
Oral cavity squamous cell carcinoma (OCSCC) is a prevalent surgically treated subset of head and neck cancer with frequent recurrence and poor survival. Immunotherapy has demonstrated efficacy in recurrent/metastatic head and neck cancer. However, whether antitumor responses could be fostered by neoadjuvant presurgical immunotherapy remains unclear. Using a Simon's two-stage design, we present results of a single-arm phase-II trial where 12 patients with stage II-IVA OCSCC received 3 to 4 biweekly doses of 3 mg/kg nivolumab followed by definitive surgical resection with curative intent. Presurgical nivolumab therapy in this cohort shows an overall response rate of 33% (n = 4 patients; 95% CI: 12%-53%). With a median follow up of 2.23 years, 10 out of 12 treated patients remain alive. Neoadjuvant nivolumab is safe, well-tolerated, and is not associated with delays in definitive surgical treatment in this study. This work demonstrates feasibility and safety for incorporation of nivolumab in the neoadjuvant setting for OCSCC (ClinicalTrials.gov: NCT03021993).
Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias Bucais/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Nivolumabe/uso terapêutico , Receptor de Morte Celular Programada 1/genética , Idoso , Antineoplásicos Imunológicos/uso terapêutico , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/cirurgia , Estudos de Coortes , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/imunologia , Neoplasias Bucais/mortalidade , Neoplasias Bucais/cirurgia , Terapia Neoadjuvante/métodos , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Análise de Sobrevida , Resultado do TratamentoRESUMO
Rationally sequencing and combining PD-1/L1-and MAPK-targeted therapies may overcome innate and acquired resistance. Since increased clinical benefit of MAPK inhibitors (MAPKi) is associated with previous immune checkpoint therapy, we compare the efficacies of sequential and/or combinatorial regimens in subcutaneous murine models of melanoma driven by BrafV600, Nras, or Nf1 mutations as well as colorectal and pancreatic carcinoma driven by KrasG12C. Anti-PD-1/L1 lead-in preceding MAPKi combination optimizes response durability by promoting pro-inflammatory polarization of macrophages and clonal expansion of interferon-γhi, and CD8+ cytotoxic and proliferative (versus CD4+ regulatory) T cells that highly express activation genes. Since therapeutic resistance of melanoma brain metastasis (MBM) limits patient survival, we demonstrate that sequencing anti-PD-1/L1 therapy before MAPKi combination suppresses MBM and improves mouse survival with robust T cell clonal expansion in both intracranial and extracranial metastatic sites. We propose clinically testing brief anti-PD-1/L1 (± anti-CTLA-4) dosing before MAPKi co-treatment to suppress therapeutic resistance.
Assuntos
Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia/métodos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Animais , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , CamundongosRESUMO
Advances in immune checkpoint therapy and targeted therapy have led to improvement in overall survival for patients with advanced melanoma. Single agent checkpoint PD-1 blockade and combination with BRAF/MEK targeted therapy demonstrated benefit in overall survival (OS). Superior response rates have been demonstrated with combined PD-1/CTLA-4 blockade, with a significant OS benefit compared with single-agent PD-1 blockade. Despite the progress in diagnosis of melanocytic lesions, correct classification of patients, selection of appropriate adjuvant and systemic therapies, and prediction of response to therapy remain real challenges in melanoma. Improved understanding of the tumor microenvironment, tumor immunity and response to therapy has prompted extensive translational and clinical research in melanoma. Development of novel biomarker platforms may help to improve diagnostics and predictive accuracy for selection of patients for specific treatment. There is a growing evidence that genomic and immune features of pre-treatment tumor biopsies may correlate with response in patients with melanoma and other cancers but they have yet to be fully characterized and implemented clinically. Overall, the progress in melanoma therapeutics and translational research will help to optimize treatment regimens to overcome resistance and develop robust biomarkers to guide clinical decision-making. During the Melanoma Bridge meeting (December 3rd-5th, 2020, Italy) we reviewed the currently approved systemic and local therapies for advanced melanoma and discussed novel biomarker strategies and advances in precision medicine.
Assuntos
Imunoterapia , Melanoma , Humanos , Itália , Melanoma/tratamento farmacológico , Terapia de Alvo Molecular , Microambiente TumoralRESUMO
Wound healing is a multi-step process to rapidly restore the barrier function. This process is often impaired in diabetic patients resulting in chronic wounds and amputation. We previously found that paradoxical activation of the mitogen-activated protein kinase (MAPK) pathway via topical administration of the BRAF inhibitor vemurafenib accelerates wound healing by activating keratinocyte proliferation and reepithelialization pathways in healthy mice. Herein, we investigated whether this wound healing acceleration also occurs in impaired diabetic wounds and found that topical vemurafenib not only improves wound healing in a murine diabetic wound model but unexpectedly promotes hair follicle regeneration. Hair follicles expressing Sox-9 and K15 surrounded by CD34+ stroma were found in wounds of diabetic and non-diabetic mice, and their formation can be prevented by blocking downstream MEK signaling. Thus, topically applied BRAF inhibitors may accelerate wound healing, and promote the restoration of improved skin architecture in both normal and impaired wounds.
Assuntos
Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Regeneração/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Administração Tópica , Animais , Diabetes Mellitus Experimental/patologia , Feminino , Folículo Piloso/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Obesos , Proteínas Proto-Oncogênicas B-raf/metabolismo , Pele/patologia , Vemurafenib/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/metabolismoRESUMO
Functional evaluation of genetic lesions can discover a role in cancer initiation and progression and help develop novel therapeutic strategies. We previously identified the negative MAPK regulator SPRED1 as a novel tumor suppressor in KIT-driven melanoma. Here, we show that SPRED1 is also frequently deleted in human melanoma driven by mutant BRAF. We found that SPRED1 inactivation in human melanoma cell lines and primary zebrafish melanoma conferred resistance to BRAFV600E inhibition in vitro and in vivo. Mechanistically, SPRED1 loss promoted melanoma cell proliferation under mutant BRAF inhibition by reactivating MAPK activity. Consistently, biallelic deletion of SPRED1 was observed in a patient whose melanoma acquired resistance to MAPK-targeted therapy. These studies combining work in human cells and in vivo modeling in zebrafish demonstrate a new mechanism of resistance to BRAFV600E inhibition in melanoma.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Resistencia a Medicamentos Antineoplásicos/genética , Deleção de Genes , Sistema de Sinalização das MAP Quinases , Melanoma/enzimologia , Melanoma/genética , Inibidores de Proteínas Quinases/farmacologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melanoma/patologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/metabolismo , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Proteína Supressora de Tumor p53/metabolismo , Peixe-ZebraRESUMO
MAPK targeting in cancer often fails due to MAPK reactivation. MEK inhibitor (MEKi) monotherapy provides limited clinical benefits but may serve as a foundation for combination therapies. Here, we showed that combining a type II RAF inhibitor (RAFi) with an allosteric MEKi durably prevents and overcomes acquired resistance among cancers with KRAS, NRAS, NF1, BRAF non-V600, and BRAF V600 mutations. Tumor cell-intrinsically, type II RAFi plus MEKi sequester MEK in RAF complexes, reduce MEK/MEK dimerization, and uncouple MEK from ERK in acquired-resistant tumor subpopulations. Immunologically, this combination expands memory and activated/exhausted CD8+ T cells, and durable tumor regression elicited by this combination requires CD8+ T cells, which can be reinvigorated by anti-PD-L1 therapy. Whereas MEKi reduces dominant intratumoral T-cell clones, type II RAFi cotreatment reverses this effect and promotes T-cell clonotypic expansion. These findings rationalize the clinical development of type II RAFi plus MEKi and their further combination with PD-1/L1-targeted therapy. SIGNIFICANCE: Type I RAFi + MEKi are indicated only in certain BRAF V600MUT cancers. In contrast, type II RAFi + MEKi are durably active against acquired MEKi resistance across broad cancer indications, which reveals exquisite MAPK addiction. Allosteric modulation of MAPK protein/protein interactions and temporal preservation of intratumoral CD8+ T cells are mechanisms that may be further exploited.This article is highlighted in the In This Issue feature, p. 521.
Assuntos
Resistencia a Medicamentos Antineoplásicos , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Humanos , Imunidade Celular/efeitos dos fármacos , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Mutação , Neoplasias/tratamento farmacológico , Neoplasias/etiologia , Neoplasias/metabolismo , Neoplasias/patologia , Ligação Proteica , Estabilidade Proteica , Resultado do Tratamento , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Preclinical modeling suggests that intermittent BRAF inhibitor therapy may delay acquired resistance when blocking oncogenic BRAFV600 in melanoma1,2. We conducted S1320, a randomized, open-label, phase 2 clinical trial (NCT02196181) evaluating whether intermittent dosing of the BRAF inhibitor dabrafenib and the MEK inhibitor trametinib improves progression-free survival in patients with metastatic and unresectable BRAFV600 melanoma. Patients were enrolled at 68 academic and community sites nationally. All patients received continuous dabrafenib and trametinib during an 8-week lead-in period, after which patients with non-progressing tumors were randomized to either continuous or intermittent dosing of both drugs on a 3-week-off, 5-week-on schedule. The trial has completed accrual and 206 patients with similar baseline characteristics were randomized 1:1 to the two study arms (105 to continuous dosing, 101 to intermittent dosing). Continuous dosing yielded a statistically significant improvement in post-randomization progression-free survival compared with intermittent dosing (median 9.0 months versus 5.5 months, P = 0.064, pre-specified two-sided α = 0.2). Therefore, contrary to the initial hypothesis, intermittent dosing did not improve progression-free survival in patients. There were no differences in the secondary outcomes, including overall survival and the overall incidence of treatment-associated toxicity, between the two groups.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Imidazóis/administração & dosagem , Melanoma/tratamento farmacológico , Oximas/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Piridonas/administração & dosagem , Pirimidinonas/administração & dosagem , Neoplasias Cutâneas/tratamento farmacológico , Administração Oral , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Esquema de Medicação , Feminino , Humanos , Imidazóis/efeitos adversos , MAP Quinase Quinase Quinases/antagonistas & inibidores , Masculino , Melanoma/genética , Melanoma/mortalidade , Melanoma/patologia , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Oximas/efeitos adversos , Inibidores de Proteínas Quinases/efeitos adversos , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Piridonas/efeitos adversos , Pirimidinonas/efeitos adversos , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Análise de Sobrevida , Resultado do Tratamento , Adulto JovemRESUMO
The melanoma treatment landscape changed in 2011 with the approval of the first anti-cytotoxic T-lymphocyte-associated protein (CTLA)-4 checkpoint inhibitor and of the first BRAF-targeted monoclonal antibody, both of which significantly improved overall survival (OS). Since then, improved understanding of the tumor microenvironment (TME) and tumor immune-evasion mechanisms has resulted in new approaches to targeting and harnessing the host immune response. The approval of new immune and targeted therapies has further improved outcomes for patients with advanced melanoma and other combination modalities are also being explored such as chemotherapy, radiotherapy, electrochemotherapy and surgery. In addition, different strategies of drugs administration including sequential or combination treatment are being tested. Approaches to overcome resistance and to potentiate the immune response are being developed. Increasing evidence emerges that tissue and blood-based biomarkers can predict the response to a therapy. The latest findings in melanoma research, including insights into the tumor microenvironment and new biomarkers, improved understanding of tumor immune response and resistance, novel approaches for combination strategies and the role of neoadjuvant and adjuvant therapy, were the focus of discussions at the Melanoma Bridge meeting (5-7 December, 2019, Naples, Italy), which are summarized in this report.