RESUMO
Fast amoeboid migration is critical for developmental processes and can be hijacked by cancer cells to enhance metastatic dissemination. This migratory behavior is tightly controlled by high levels of actomyosin contractility, but how it is coupled to other cytoskeletal components is poorly understood. Septins are increasingly recognized as novel cytoskeletal components, but details on their regulation and contribution to migration are lacking. Here, we show that the septin regulator Cdc42EP5 is consistently required for amoeboid melanoma cells to invade and migrate into collagen-rich matrices and locally invade and disseminate in vivo. Cdc42EP5 associates with actin structures, leading to increased actomyosin contractility and amoeboid migration. Cdc42EP5 affects these functions through SEPT9-dependent F-actin cross-linking, which enables the generation of F-actin bundles required for the sustained stabilization of highly contractile actomyosin structures. This study provides evidence that Cdc42EP5 is a regulator of cancer cell motility that coordinates actin and septin networks and describes a unique role for SEPT9 in melanoma invasion and metastasis.
Assuntos
Actomiosina/metabolismo , Movimento Celular/fisiologia , Reguladores de Proteínas de Ligação ao GTP/metabolismo , Septinas/metabolismo , Actinas/metabolismo , Animais , Linhagem Celular Tumoral , Citoesqueleto/metabolismo , Adesões Focais/metabolismo , Humanos , Melanoma/metabolismo , Camundongos , Neoplasias Cutâneas/metabolismo , Melanoma Maligno CutâneoRESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMO
Approximately 30% of ERα breast cancer patients relapse with metastatic disease following adjuvant endocrine therapies. The connection between acquisition of drug resistance and invasive potential is poorly understood. In this study, we demonstrate that the type II keratin topological associating domain undergoes epigenetic reprogramming in aromatase inhibitors (AI)-resistant cells, leading to Keratin-80 (KRT80) upregulation. KRT80 expression is driven by de novo enhancer activation by sterol regulatory element-binding protein 1 (SREBP1). KRT80 upregulation directly promotes cytoskeletal rearrangements at the leading edge, increased focal adhesion and cellular stiffening, collectively promoting cancer cell invasion. Shearwave elasticity imaging performed on prospectively recruited patients confirms KRT80 levels correlate with stiffer tumors. Immunohistochemistry showed increased KRT80-positive cells at relapse and, using several clinical endpoints, KRT80 expression associates with poor survival. Collectively, our data uncover an unpredicted and potentially targetable direct link between epigenetic and cytoskeletal reprogramming promoting cell invasion in response to chronic AI treatment.
Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/patologia , Citoesqueleto/patologia , Queratinas Tipo II/genética , Recidiva Local de Neoplasia/patologia , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Antineoplásicos Hormonais/uso terapêutico , Inibidores da Aromatase/farmacologia , Inibidores da Aromatase/uso terapêutico , Mama/patologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Citoesqueleto/genética , Resistencia a Medicamentos Antineoplásicos/genética , Elementos Facilitadores Genéticos/genética , Epigênese Genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Queratinas Tipo II/metabolismo , Células MCF-7 , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/mortalidade , Prognóstico , Domínios Proteicos/genética , Regulação para CimaRESUMO
Aggressive behaviours of solid tumours are highly influenced by the tumour microenvironment. Multiple signalling pathways can affect the normal function of stromal fibroblasts in tumours, but how these events are coordinated to generate tumour-promoting cancer-associated fibroblasts (CAFs) is not well understood. Here we show that stromal expression of Dickkopf-3 (DKK3) is associated with aggressive breast, colorectal and ovarian cancers. We demonstrate that DKK3 is a HSF1 effector that modulates the pro-tumorigenic behaviour of CAFs in vitro and in vivo. DKK3 orchestrates a concomitant activation of ß-catenin and YAP/TAZ. Whereas ß-catenin is dispensable for CAF-mediated ECM remodelling, cancer cell growth and invasion, DKK3-driven YAP/TAZ activation is required to induce tumour-promoting phenotypes. Mechanistically, DKK3 in CAFs acts via canonical Wnt signalling by interfering with the negative regulator Kremen and increasing cell-surface levels of LRP6. This work reveals an unpredicted link between HSF1, Wnt signalling and YAP/TAZ relevant for the generation of tumour-promoting CAFs.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Fatores de Transcrição de Choque Térmico/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Fosfoproteínas/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Linhagem Celular , Células Cultivadas , Quimiocinas , Perfilação da Expressão Gênica , Fatores de Transcrição de Choque Térmico/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intracelular , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos Nus , Camundongos Transgênicos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Fosfoproteínas/genética , Transativadores , Fatores de Transcrição/genética , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Via de Sinalização Wnt/genética , beta Catenina/genética , beta Catenina/metabolismoRESUMO
Rho family GTPases such as Cdc42 are key regulators of essential cellular processes through their effects on cytoskeletal dynamics, signaling and gene expression. Rho GTPases modulate these functions by engaging a wide variety of downstream effectors. Among these effectors is the largely understudied Cdc42EP/BORG family of Cdc42 effectors. BORG proteins have been linked to actin and septin regulation, but their role in development and disease is only starting to emerge. Recently, Cdc42EP3/BORG2 was shown to coordinate actin and septin cytoskeleton rearrangements in cancer-associated fibroblasts (CAFs). Interestingly, Cdc42EP3 expression potentiated cellular responses to mechanical stimulation leading to signaling and transcriptional adaptations required for the emergence of a fully activated CAF phenotype. These findings uncover a novel role for the BORG/septin network in cancer. Here, we demonstrate that Cdc42EP3 function in CAFs relies on tight regulation by Cdc42.
Assuntos
Fibroblastos Associados a Câncer/metabolismo , Reguladores de Proteínas de Ligação ao GTP/metabolismo , Neoplasias/metabolismo , Proteína cdc42 de Ligação ao GTP/metabolismo , Actinas/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Septinas/metabolismo , Transdução de SinaisRESUMO
Despite being discovered more than 15 years ago, the Borg (binder of Rho GTPases) family of Cdc42 effector proteins (Cdc42EP1-5) remains largely uncharacterised and relatively little is known about their structure, regulation and role in development and disease. Recent studies are starting to unravel some of the key functional and mechanistic aspects of the Borg proteins, including their role in cytoskeletal remodelling and signalling. In addition, the participation of Borg proteins in important cellular processes such as cell shape, directed migration and differentiation is slowly emerging, directly linking Borgs with important physiological and pathological processes such as angiogenesis, neurotransmission and cancer-associated desmoplasia. Here, we review some of these findings and discuss future prospects.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Reguladores de Proteínas de Ligação ao GTP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas do Citoesqueleto , Citoesqueleto/metabolismo , Reguladores de Proteínas de Ligação ao GTP/genética , Humanos , Modelos Biológicos , Família Multigênica , Proteínas de Ligação a RNA , Transdução de Sinais , Proteínas rho de Ligação ao GTPRESUMO
Cancer-associated fibroblasts (CAFs) are non-cancerous cells found in solid tumors that remodel the tumor matrix and promote cancer invasion and angiogenesis. Here, we demonstrate that Cdc42EP3/BORG2 is required for the matrix remodeling, invasion, angiogenesis, and tumor-growth-promoting abilities of CAFs. Cdc42EP3 functions by coordinating the actin and septin networks. Furthermore, depletion of SEPT2 has similar effects to those of loss of Cdc42EP3, indicating a role for the septin network in the tumor stroma. Cdc42EP3 is upregulated early in fibroblast activation and precedes the emergence of the highly contractile phenotype characteristic of CAFs. Depletion of Cdc42EP3 in normal fibroblasts prevents their activation by cancer cells. We propose that Cdc42EP3 sensitizes fibroblasts to further cues-in particular, those activating actomyosin contractility-and thereby enables the generation of the pathological activated fibroblast state.