RESUMO
The last 50 years have witnessed extraordinary developments in understanding mechanisms of carcinogenesis, synthesized as the hallmarks of cancer. Despite this logical framework, our understanding of the molecular basis of systemic manifestations and the underlying causes of cancer-related death remains incomplete. Looking forward, elucidating how tumors interact with distant organs and how multifaceted environmental and physiological parameters impinge on tumors and their hosts will be crucial for advances in preventing and more effectively treating human cancers. In this perspective, we discuss complexities of cancer as a systemic disease, including tumor initiation and promotion, tumor micro- and immune macro-environments, aging, metabolism and obesity, cancer cachexia, circadian rhythms, nervous system interactions, tumor-related thrombosis, and the microbiome. Model systems incorporating human genetic variation will be essential to decipher the mechanistic basis of these phenomena and unravel gene-environment interactions, providing a modern synthesis of molecular oncology that is primed to prevent cancers and improve patient quality of life and cancer outcomes.
Assuntos
Neoplasias , Humanos , Carcinogênese , Microbiota , Neoplasias/genética , Neoplasias/patologia , Neoplasias/terapia , Obesidade/complicações , Qualidade de VidaRESUMO
Tumor cells do not exist in isolation in vivo, and carcinogenesis depends on the surrounding tumor microenvironment (TME), composed of a myriad of cell types and biophysical and biochemical components. Fibroblasts are integral in maintaining tissue homeostasis. However, even before a tumor develops, pro-tumorigenic fibroblasts in close proximity can provide the fertile 'soil' to the cancer 'seed' and are known as cancer-associated fibroblasts (CAFs). In response to intrinsic and extrinsic stressors, CAFs reorganize the TME enabling metastasis, therapeutic resistance, dormancy and reactivation by secreting cellular and acellular factors. In this review, we summarize the recent discoveries on CAF-mediated cancer progression with a particular focus on fibroblast heterogeneity and plasticity.
Assuntos
Fibroblastos Associados a Câncer , Neoplasias , Humanos , Fibroblastos Associados a Câncer/metabolismo , Carcinogênese , Neoplasias/patologia , Microambiente Tumoral/fisiologiaRESUMO
Recent reports indicate that hypoxia influences the circadian clock through the transcriptional activities of hypoxia-inducible factors (HIFs) at clock genes. Unexpectedly, we uncover a profound disruption of the circadian clock and diurnal transcriptome when hypoxic cells are permitted to acidify to recapitulate the tumor microenvironment. Buffering against acidification or inhibiting lactic acid production fully rescues circadian oscillation. Acidification of several human and murine cell lines, as well as primary murine T cells, suppresses mechanistic target of rapamycin complex 1 (mTORC1) signaling, a key regulator of translation in response to metabolic status. We find that acid drives peripheral redistribution of normally perinuclear lysosomes away from perinuclear RHEB, thereby inhibiting the activity of lysosome-bound mTOR. Restoring mTORC1 signaling and the translation it governs rescues clock oscillation. Our findings thus reveal a model in which acid produced during the cellular metabolic response to hypoxia suppresses the circadian clock through diminished translation of clock constituents.
Assuntos
Hipóxia Celular , Relógios Circadianos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Aminoácidos Dicarboxílicos/farmacologia , Animais , Proteínas CLOCK/metabolismo , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular , Células Cultivadas , Relógios Circadianos/efeitos dos fármacos , Meios de Cultura/química , Fatores de Iniciação em Eucariotos , Concentração de Íons de Hidrogênio , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Camundongos , Fosfoproteínas/antagonistas & inibidores , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Proteína Enriquecida em Homólogo de Ras do Encéfalo/metabolismo , Transdução de Sinais/efeitos dos fármacos , Linfócitos T/citologia , Linfócitos T/metabolismo , Transcriptoma/efeitos dos fármacos , Proteína 2 do Complexo Esclerose Tuberosa/deficiência , Proteína 2 do Complexo Esclerose Tuberosa/genéticaRESUMO
Even among genetically identical cancer cells, resistance to therapy frequently emerges from a small subset of those cells1-7. Molecular differences in rare individual cells in the initial population enable certain cells to become resistant to therapy7-9; however, comparatively little is known about the variability in the resistance outcomes. Here we develop and apply FateMap, a framework that combines DNA barcoding with single-cell RNA sequencing, to reveal the fates of hundreds of thousands of clones exposed to anti-cancer therapies. We show that resistant clones emerging from single-cell-derived cancer cells adopt molecularly, morphologically and functionally distinct resistant types. These resistant types are largely predetermined by molecular differences between cells before drug addition and not by extrinsic factors. Changes in the dose and type of drug can switch the resistant type of an initial cell, resulting in the generation and elimination of certain resistant types. Samples from patients show evidence for the existence of these resistant types in a clinical context. We observed diversity in resistant types across several single-cell-derived cancer cell lines and cell types treated with a variety of drugs. The diversity of resistant types as a result of the variability in intrinsic cell states may be a generic feature of responses to external cues.
Assuntos
Antineoplásicos , Células Clonais , Resistencia a Medicamentos Antineoplásicos , Neoplasias , Humanos , Células Clonais/efeitos dos fármacos , Células Clonais/metabolismo , Células Clonais/patologia , Código de Barras de DNA Taxonômico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , RNA-Seq , Análise da Expressão Gênica de Célula Única , Células Tumorais Cultivadas , Antineoplásicos/farmacologiaRESUMO
Disseminated cancer cells from primary tumours can seed in distal tissues, but may take several years to form overt metastases, a phenomenon that is termed tumour dormancy. Despite its importance in metastasis and residual disease, few studies have been able to successfully characterize dormancy within melanoma. Here we show that the aged lung microenvironment facilitates a permissive niche for efficient outgrowth of dormant disseminated cancer cells-in contrast to the aged skin, in which age-related changes suppress melanoma growth but drive dissemination. These microenvironmental complexities can be explained by the phenotype switching model, which argues that melanoma cells switch between a proliferative cell state and a slower-cycling, invasive state1-3. It was previously shown that dermal fibroblasts promote phenotype switching in melanoma during ageing4-8. We now identify WNT5A as an activator of dormancy in melanoma disseminated cancer cells within the lung, which initially enables the efficient dissemination and seeding of melanoma cells in metastatic niches. Age-induced reprogramming of lung fibroblasts increases their secretion of the soluble WNT antagonist sFRP1, which inhibits WNT5A in melanoma cells and thereby enables efficient metastatic outgrowth. We also identify the tyrosine kinase receptors AXL and MER as promoting a dormancy-to-reactivation axis within melanoma cells. Overall, we find that age-induced changes in distal metastatic microenvironments promote the efficient reactivation of dormant melanoma cells in the lung.
Assuntos
Envelhecimento , Pulmão , Melanoma , Metástase Neoplásica , Células Estromais , Microambiente Tumoral , Idoso , Envelhecimento/patologia , Fibroblastos/patologia , Humanos , Pulmão/patologia , Melanoma/patologia , Invasividade Neoplásica/patologia , Metástase Neoplásica/patologia , Neoplasia Residual , Proteínas Proto-Oncogênicas , Receptores Proteína Tirosina Quinases , Pele/patologia , Células Estromais/patologia , Proteína Wnt-5a , c-Mer Tirosina Quinase , Receptor Tirosina Quinase AxlRESUMO
Metastatic melanoma is an aggressive disease, despite recent improvements in therapy. Eradicating all melanoma cells even in drug-sensitive tumors is unsuccessful in patients because a subset of cells can transition to a slow-cycling state, rendering them resistant to most targeted therapy. It is still unclear what pathways define these subpopulations and promote this resistant phenotype. In the current study, we show that Wnt5A, a non-canonical Wnt ligand that drives a metastatic, therapy-resistant phenotype, stabilizes the half-life of p53 and uses p53 to initiate a slow-cycling state following stress (DNA damage, targeted therapy, and aging). Inhibiting p53 blocks the slow-cycling phenotype and sensitizes melanoma cells to BRAF/MEK inhibition. In vivo, this can be accomplished with a single dose of p53 inhibitor at the commencement of BRAF/MEK inhibitor therapy. These data suggest that taking the paradoxical approach of inhibiting rather than activating wild-type p53 may sensitize previously resistant metastatic melanoma cells to therapy.
Assuntos
Melanoma/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Wnt-5a/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , MAP Quinase Quinase Quinases/metabolismo , Melanoma/genética , Melanoma/patologia , Terapia de Alvo Molecular , Mutação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologia , Microambiente Tumoral/efeitos dos fármacos , Proteína Supressora de Tumor p53/fisiologiaRESUMO
RNA labeling in situ has enormous potential to visualize transcripts and quantify their levels in single cells, but it remains challenging to produce high levels of signal while also enabling multiplexed detection of multiple RNA species simultaneously. Here, we describe clampFISH 2.0, a method that uses an inverted padlock design to efficiently detect many RNA species and exponentially amplify their signals at once, while also reducing the time and cost compared with the prior clampFISH method. We leverage the increased throughput afforded by multiplexed signal amplification and sequential detection to detect 10 different RNA species in more than 1 million cells. We also show that clampFISH 2.0 works in tissue sections. We expect that the advantages offered by clampFISH 2.0 will enable many applications in spatial transcriptomics.
Assuntos
RNA , Transcriptoma , RNA/genéticaRESUMO
Cancer is a disease of ageing. Clinically, aged cancer patients tend to have a poorer prognosis than young. This may be due to accumulated cellular damage, decreases in adaptive immunity, and chronic inflammation. However, the effects of the aged microenvironment on tumour progression have been largely unexplored. Since dermal fibroblasts can have profound impacts on melanoma progression, we examined whether age-related changes in dermal fibroblasts could drive melanoma metastasis and response to targeted therapy. Here we find that aged fibroblasts secrete a Wnt antagonist, sFRP2, which activates a multi-step signalling cascade in melanoma cells that results in a decrease in ß-catenin and microphthalmia-associated transcription factor (MITF), and ultimately the loss of a key redox effector, APE1. Loss of APE1 attenuates the response of melanoma cells to DNA damage induced by reactive oxygen species, rendering the cells more resistant to targeted therapy (vemurafenib). Age-related increases in sFRP2 also augment both angiogenesis and metastasis of melanoma cells. These data provide an integrated view of how fibroblasts in the aged microenvironment contribute to tumour progression, offering new possibilities for the design of therapy for the elderly.
Assuntos
Envelhecimento/metabolismo , Resistencia a Medicamentos Antineoplásicos , Melanoma/tratamento farmacológico , Melanoma/patologia , Proteínas de Membrana/metabolismo , Metástase Neoplásica , Microambiente Tumoral , Adulto , Animais , Linhagem Celular Tumoral , Meios de Cultivo Condicionados/farmacologia , Dano ao DNA , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Progressão da Doença , Fibroblastos/metabolismo , Humanos , Indóis/farmacologia , Indóis/uso terapêutico , Masculino , Melanoma/irrigação sanguínea , Melanoma/genética , Camundongos , Fator de Transcrição Associado à Microftalmia/metabolismo , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Neovascularização Patológica , Estresse Oxidativo , Fenótipo , Espécies Reativas de Oxigênio/metabolismo , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Vemurafenib , Via de Sinalização Wnt , Proteína Wnt1/antagonistas & inibidores , beta Catenina/metabolismoRESUMO
Cancer cell invasion from primary tumors is mediated by a complex interplay between cellular adhesions, actomyosin-driven contractility, and the physical characteristics of the extracellular matrix (ECM). Here, we incorporate a mechanochemical free-energy-based approach to elucidate how the two-way feedback loop between cell contractility (induced by the activity of chemomechanical interactions such as Ca2+ and Rho signaling pathways) and matrix fiber realignment and strain stiffening enables the cells to polarize and develop contractile forces to break free from the tumor spheroids and invade into the ECM. Interestingly, through this computational model, we are able to identify a critical stiffness that is required by the matrix to break intercellular adhesions and initiate cell invasion. Also, by considering the kinetics of the cell movement, our model predicts a biphasic invasiveness with respect to the stiffness of the matrix. These predictions are validated by analyzing the invasion of melanoma cells in collagen matrices of varying concentration. Our model also predicts a positive correlation between the elongated morphology of the invading cells and the alignment of fibers in the matrix, suggesting that cell polarization is directly proportional to the stiffness and alignment of the matrix. In contrast, cells in nonfibrous matrices are found to be rounded and not polarized, underscoring the key role played by the nonlinear mechanics of fibrous matrices. Importantly, our model shows that mechanical principles mediated by the contractility of the cells and the nonlinearity of the ECM behavior play a crucial role in determining the phenotype of the cell invasion.
Assuntos
Matriz Extracelular/patologia , Melanoma/patologia , Invasividade Neoplásica/patologia , Actomiosina/metabolismo , Adesão Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Colágeno/metabolismo , Simulação por Computador , Elasticidade/fisiologia , Matriz Extracelular/metabolismo , Retroalimentação , Humanos , Melanoma/metabolismo , Dinâmica não LinearRESUMO
Melanoma accounts for only 4% of malignant neoplasms of the skin, but is considered the most serious because it is highly deadly. Mutations in the MAPK (Ras-Raf-MEK-ERK) pathway is closely linked to the lack of control of cell proliferation. Especially in melanoma, this pathway has become a target for the development of oncogene-targeted therapies, such as the potent inhibitors of v-Raf murine sarcoma viral oncogene homolog B (BRAFi) and mitogen-activated protein kinase kinase (MEKi). Very high rates of response have been achieved, but most patients are relapsed due to the development of resistance, justifying the constant search for new therapeutic compounds. Early results from our group indicated that 4-nerolidylcatechol (4-NC), a catechol compound extracted from Pothomorphe umbellata, induces DNA damage, ROS production, increased p53 expression culminating in apoptosis in melanoma but with no data regarding the 4-NC effects in cells resistant to BRAFi or MEKi. Therefore, here we evaluated the role of 4-NC alone or in combination with BRAFi/MEKi in resistant melanoma cells. Double-resistant cells were generated and characterized by MAPK pathway reactivation. 4-NC alone or in combination (30 µM) with MAPK inhibitors was cytotoxic, inhibited colony formation and decreased invasiveness in two and three-dimensional cell culture models of treatment-naïve, BRAFi-resistant and BRAF/MEKi double-resistant melanoma cells. Apoptosis induction was demonstrated in resistant and double-resistant melanoma cell lines after 4-NC treatments. 4-NC showed important ability to induce apoptosis via Endoplasmatic Reticulum (ER) stress and specifically BiP and CHOP that had increased protein expression in all melanoma cell lines proving to be part of the ER stress pathway activation. CHOP knockdown slightly but enough increases cellular viability following 4-NC treatment indicating that apoptosis observed is partially dependent on CHOP. In summary, we show that 4-NC is a compound with activity against cutaneous melanoma, including resistant cells to clinically approved therapies.
Assuntos
Antineoplásicos/farmacologia , Catecóis/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológicoRESUMO
Molecular therapies are hallmarks of "personalized" medicine, but how tumors adapt to these agents is not well-understood. Here we show that small-molecule inhibitors of phosphatidylinositol 3-kinase (PI3K) currently in the clinic induce global transcriptional reprogramming in tumors, with activation of growth factor receptors, (re)phosphorylation of Akt and mammalian target of rapamycin (mTOR), and increased tumor cell motility and invasion. This response involves redistribution of energetically active mitochondria to the cortical cytoskeleton, where they support membrane dynamics, turnover of focal adhesion complexes, and random cell motility. Blocking oxidative phosphorylation prevents adaptive mitochondrial trafficking, impairs membrane dynamics, and suppresses tumor cell invasion. Therefore, "spatiotemporal" mitochondrial respiration adaptively induced by PI3K therapy fuels tumor cell invasion, and may provide an important antimetastatic target.
Assuntos
Inibidores Enzimáticos/farmacologia , Mitocôndrias/efeitos dos fármacos , Invasividade Neoplásica , Inibidores de Fosfoinositídeo-3 Quinase , Transporte Biológico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Citoesqueleto/metabolismo , Metabolismo Energético , Humanos , Mitocôndrias/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de SinaisRESUMO
Epithelial ovarian cancer (EOC), the deadliest of gynaecological cancers, is a disease that remains difficult to detect early and treat efficiently. A significant challenge for researchers in the field is that the aetiology of EOC and the molecular pathways important for its development are poorly understood. Moreover, precursor lesions have not been readily identifiable, making the mechanisms of EOC progression difficult to delineate. In order to address these issues, several genetically-defined ovarian mouse models have been generated in the past 15 years. However, because of the recent suggestion that most EOCs may not originate from the ovarian surface 'epithelium', but from other tissues of the female genital tract, some models may need to be re-evaluated within this new paradigm. In this review, we examine several genetically-defined EOC models and discuss how the new paradigm may explain some of the features of these models. A better understanding of the strengths and limitations of the current EOC mouse models will undoubtedly allow us to utilize these tools to better understand the biology of the disease and develop new approaches for EOC prevention, detection, and treatment.
Assuntos
Carcinoma in Situ/genética , Modelos Animais de Doenças , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , Adenoviridae , Animais , Carcinoma in Situ/patologia , Carcinoma Epitelial do Ovário , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Células Epiteliais/patologia , Neoplasias das Tubas Uterinas/genética , Feminino , Genes p53/genética , Glicoproteínas/genética , Humanos , Camundongos , Camundongos Transgênicos , Mutação/genética , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/patologia , PTEN Fosfo-Hidrolase/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína do Retinoblastoma/genéticaRESUMO
The outgrowth of metastatic and therapy-resistant subpopulations in cancer remains a critical barrier for the successful treatment of this disease. In melanoma, invasion and proliferation are uncoupled, such that highly proliferative melanoma cells are less likely to be invasive, and vice versa. The transition between each state is likely a dynamic rather than a static, permanent change. This is referred to as "phenotype switching". Wnt signaling pathways drive phenotypic changes and promote therapy resistance in melanoma, as well as play roles in the modulation of the immune microenvironment. Three Wnt signaling pathways play a role in melanoma progression, canonical (ß-catenin dependent), polar cell polarity (PCP), and the Wnt/Ca²âº pathway. Here we summarize phenotype plasticity and its role in therapy resistance and immune evasion. Targeting the Wnt signaling pathways may be an effective way to overcome tumor plasticity in melanoma.
Assuntos
Melanoma/metabolismo , Melanoma/patologia , Proteínas de Neoplasias/metabolismo , Microambiente Tumoral , Proteínas Wnt/metabolismo , Via de Sinalização Wnt , Animais , Diferenciação Celular , Plasticidade Celular , Proliferação de Células , Humanos , Modelos Biológicos , Invasividade Neoplásica , FenótipoRESUMO
Although the clinical landscape of melanoma is improving rapidly, metastatic melanoma remains a deadly disease. Age remains one of the greatest risk factors for melanoma, and patients older than 55 have a much poorer prognosis than younger individuals, even when the data are controlled for grade and stage. The reasons for this disparity have not been fully uncovered, but there is some recent evidence that Wnt signalling may have a role. Wnt signalling is known to have roles both in cancer progression as well as in organismal ageing. In melanoma, the interplay of Wnt signalling pathways is complex, with different members of the Wnt family guiding different aspects of invasion and proliferation. Here, we will briefly review the current literature addressing the roles of different Wnt pathways in melanoma pathogenesis, provide an overview of Wnt signalling during ageing, and discuss the intersection between melanoma and ageing in terms of Wnt signalling.
Assuntos
Envelhecimento , Melanoma/metabolismo , Transdução de Sinais , Proteínas Wnt/metabolismo , Humanos , Melanoma/patologia , Prognóstico , Microambiente TumoralRESUMO
Mitochondria control bioenergetics and cell fate decisions, but how they influence nuclear gene expression is understood poorly. Here, we show that deletion or reduction in the levels of cyclophilin D (CypD, also called Ppif), a mitochondrial matrix peptidyl prolyl isomerase and apoptosis regulator, results in increased cell proliferation and enhanced cell migration and invasion. These responses are associated with extensive transcriptional changes, modulation of a chemokine/chemokine receptor gene signature, and activation of the pleiotropic inflammatory mediator, STAT3. In the absence of CypD, active STAT3 enhances cell proliferation via accelerated entry into S-phase and stimulates autocrine/paracrine cell motility through Cxcl12-Cxcr4-directed chemotaxis. Therefore, CypD directs mitochondria-to-nuclei inflammatory gene expression in normal and tumor cells. This pathway may contribute to malignant traits under conditions of CypD modulation.
Assuntos
Quimiocinas/metabolismo , Ciclofilinas/metabolismo , Mitocôndrias/metabolismo , Animais , Apoptose , Ciclo Celular , Linhagem Celular Tumoral , Linhagem da Célula , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Peptidil-Prolil Isomerase F , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Células NIH 3T3 , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de SinaisRESUMO
Melanoma is the deadliest form of skin cancer in the United States, with its incidence rates rising in older populations. As the immune system undergoes age-related changes, these alterations can significantly influence tumor progression and the effectiveness of cancer treatments. Recent advancements in understanding immune checkpoint molecules have paved the way for the development of innovative immunotherapies targeting solid tumors. However, the aging tumor microenvironment can play a crucial role in modulating the response to these immunotherapeutic approaches. This review seeks to examine the intricate relationship between age-related changes in the immune system and their impact on the efficacy of immunotherapies, particularly in the context of melanoma. By exploring this complex interplay, we hope to elucidate potential strategies to optimize treatment outcomes for older patients with melanoma, and draw parallels to other cancers.
RESUMO
Metastatic melanoma is among the most enigmatic advanced cancers to clinically manage despite immense progress in the way of available therapeutic options and historic decreases in the melanoma mortality rate. Most patients with metastatic melanoma treated with modern targeted therapies (for example, BRAFV600E/K inhibitors) and/or immune checkpoint blockade (for example, anti-programmed death 1 therapy) will progress, owing to profound tumor cell plasticity fueled by genetic and nongenetic mechanisms and dichotomous host microenvironmental influences. Here we discuss the determinants of tumor heterogeneity, mechanisms of therapy resistance and effective therapy regimens that hold curative promise.
Assuntos
Resistencia a Medicamentos Antineoplásicos , Melanoma , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Microambiente Tumoral/efeitos dos fármacos , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Terapia de Alvo Molecular/métodos , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genéticaRESUMO
Melanoma, the most lethal form of skin cancer, often has worse outcomes in older patients. We previously demonstrated that an age-related decrease in the secreted extracellular matrix (ECM) protein HAPLN1 has a role in slowing melanoma progression. Here we show that HAPLN1 in the dermal ECM is sufficient to maintain the integrity of melanoma-associated blood vessels, as indicated by increased collagen and VE-cadherin expression. Specifically, we show that HAPLN1 in the ECM increases hyaluronic acid and decreases endothelial cell expression of ICAM1. ICAM1 phosphorylates and internalizes VE-cadherin, a critical determinant of vascular integrity, resulting in permeable blood vessels. We found that blocking ICAM1 reduces tumor size and metastasis in older mice. These results suggest that HAPLN1 alters endothelial ICAM1expression in an indirect, matrix-dependent manner. Targeting ICAM1 could be a potential treatment strategy for older patients with melanoma, emphasizing the role of aging in tumorigenesis.