RESUMO
Nearly all prostate cancer deaths are from metastatic castration-resistant prostate cancer (mCRPC), but there have been few whole-genome sequencing (WGS) studies of this disease state. We performed linked-read WGS on 23 mCRPC biopsy specimens and analyzed cell-free DNA sequencing data from 86 patients with mCRPC. In addition to frequent rearrangements affecting known prostate cancer genes, we observed complex rearrangements of the AR locus in most cases. Unexpectedly, these rearrangements include highly recurrent tandem duplications involving an upstream enhancer of AR in 70%-87% of cases compared with <2% of primary prostate cancers. A subset of cases displayed AR or MYC enhancer duplication in the context of a genome-wide tandem duplicator phenotype associated with CDK12 inactivation. Our findings highlight the complex genomic structure of mCRPC, nominate alterations that may inform prostate cancer treatment, and suggest that additional recurrent events in the non-coding mCRPC genome remain to be discovered.
Assuntos
Neoplasias de Próstata Resistentes à Castração/patologia , Receptores Androgênicos/genética , Sequenciamento Completo do Genoma , Idoso , Anilidas/uso terapêutico , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Elementos Facilitadores Genéticos/genética , Duplicação Gênica , Rearranjo Gênico , Genes myc , Loci Gênicos , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , PTEN Fosfo-Hidrolase/genética , Fenótipo , Antígeno Prostático Específico/sangue , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/uso terapêuticoRESUMO
Lin28, a highly conserved RNA-binding protein, has emerged as a modulator of the processing of the let-7 microRNA. This role for Lin28 has important implications for our mechanistic understanding of pluripotency, the timing of development, and oncogenesis.
Assuntos
MicroRNAs/genética , Processamento de Proteína Pós-Traducional , Proteínas de Ligação a RNA/genética , Animais , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Neoplasias/metabolismo , Células-Tronco/metabolismoRESUMO
BACKGROUND: There remains a paucity of data regarding the efficacy of immune checkpoint therapy (ICT) combinations ± vascular endothelial growth factor (VEGF) targeted therapy (TT) in translocation renal cell carcinoma (tRCC). METHODS: This is a retrospective study of patients with advanced tRCC treated with ICT combinations at 11 centers in the US, France, and Belgium. Only cases with confirmed fluorescence in situ hybridization (FISH) were included. Objective response rates (ORR) and progression-free survival (PFS) were assessed by RECIST, and overall survival (OS) was estimated by Kaplan-Meier methods. RESULTS: There were 29 patients identified with median age of 38 (21-70) years, and F:M ratio 0.9:1. FISH revealed TFE3 and TFEB translocations in 22 and 7 patients, respectively. Dual ICT and ICT + VEGF TT were used in 18 and 11 patients, respectively. Seventeen (59%) patients received ICT combinations as first-line therapy. ORR was 1/18 (5.5%) for dual ICT and 4/11 (36%) for ICT + VEGF TT. At a median follow-up of 12.9 months, median PFS was 2.8 and 5.4 months in the dual ICT and ICT + VEGF TT groups, respectively. Median OS from metastatic disease was 17.8 and 30.7 months in the dual ICT and ICT + VEGF TT groups, respectively. CONCLUSION: In this retrospective study of advanced tRCC, limited response and survival were seen after frontline dual ICT combination therapy, while ICT + VEGF TT therapy offered some efficacy. Due to the heterogeneity of tRCC, insights into the biological underpinnings are necessary to develop more effective therapies.
Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/genética , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Fator A de Crescimento do Endotélio Vascular/genética , Estudos Retrospectivos , Hibridização in Situ FluorescenteRESUMO
Plasticity of the cell state has been proposed to drive resistance to multiple classes of cancer therapies, thereby limiting their effectiveness. A high-mesenchymal cell state observed in human tumours and cancer cell lines has been associated with resistance to multiple treatment modalities across diverse cancer lineages, but the mechanistic underpinning for this state has remained incompletely understood. Here we molecularly characterize this therapy-resistant high-mesenchymal cell state in human cancer cell lines and organoids and show that it depends on a druggable lipid-peroxidase pathway that protects against ferroptosis, a non-apoptotic form of cell death induced by the build-up of toxic lipid peroxides. We show that this cell state is characterized by activity of enzymes that promote the synthesis of polyunsaturated lipids. These lipids are the substrates for lipid peroxidation by lipoxygenase enzymes. This lipid metabolism creates a dependency on pathways converging on the phospholipid glutathione peroxidase (GPX4), a selenocysteine-containing enzyme that dissipates lipid peroxides and thereby prevents the iron-mediated reactions of peroxides that induce ferroptotic cell death. Dependency on GPX4 was found to exist across diverse therapy-resistant states characterized by high expression of ZEB1, including epithelial-mesenchymal transition in epithelial-derived carcinomas, TGFß-mediated therapy-resistance in melanoma, treatment-induced neuroendocrine transdifferentiation in prostate cancer, and sarcomas, which are fixed in a mesenchymal state owing to their cells of origin. We identify vulnerability to ferroptic cell death induced by inhibition of a lipid peroxidase pathway as a feature of therapy-resistant cancer cells across diverse mesenchymal cell-state contexts.
Assuntos
Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Caderinas/metabolismo , Morte Celular , Linhagem Celular Tumoral , Linhagem da Célula , Transdiferenciação Celular , Resistencia a Medicamentos Antineoplásicos/genética , Transição Epitelial-Mesenquimal , Humanos , Ferro/metabolismo , Peróxidos Lipídicos/metabolismo , Masculino , Melanoma/tratamento farmacológico , Melanoma/enzimologia , Melanoma/metabolismo , Melanoma/patologia , Mesoderma/efeitos dos fármacos , Mesoderma/enzimologia , Mesoderma/metabolismo , Mesoderma/patologia , Neoplasias/genética , Neoplasias/patologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteômica , Proteínas Proto-Oncogênicas B-raf/genética , Reprodutibilidade dos Testes , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genéticaRESUMO
Colorectal cancer (CRC) remains a major contributor to cancer-related mortality. LIN28A and LIN28B are highly related RNA-binding protein paralogs that regulate biogenesis of let-7 microRNAs and influence development, metabolism, tissue regeneration, and oncogenesis. Here we demonstrate that overexpression of either LIN28 paralog cooperates with the Wnt pathway to promote invasive intestinal adenocarcinoma in murine models. When LIN28 alone is induced genetically, half of the resulting tumors harbor Ctnnb1 (ß-catenin) mutation. When overexpressed in Apc(Min/+) mice, LIN28 accelerates tumor formation and enhances proliferation and invasiveness. In conditional genetic models, enforced expression of a LIN28-resistant form of the let-7 microRNA reduces LIN28-induced tumor burden, while silencing of LIN28 expression reduces tumor volume and increases tumor differentiation, indicating that LIN28 contributes to tumor maintenance. We detected aberrant expression of LIN28A and/or LIN28B in 38% of a large series of human CRC samples (n = 595), where LIN28 expression levels were associated with invasive tumor growth. Our late-stage CRC murine models and analysis of primary human tumors demonstrate prominent roles for both LIN28 paralogs in promoting CRC growth and progression and implicate the LIN28/let-7 pathway as a therapeutic target.
Assuntos
Adenocarcinoma/fisiopatologia , Neoplasias Colorretais/fisiopatologia , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Proteínas Wnt/metabolismo , Animais , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Invasividade Neoplásica/genética , Invasividade Neoplásica/fisiopatologia , Proteínas de Ligação a RNA/genéticaRESUMO
BACKGROUND: MiT family translocation renal cell carcinoma (TRCC) is a rare and aggressive subgroup of renal cell carcinoma harboring high expression of c-MET. While TRCC response rates to VEGF receptor tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors are limited, efficacy of cabozantinib (a VEGFR, MET, and AXL inhibitor) in this subgroup is unclear. METHODS: We performed a multicenter, retrospective, international cohort study of patients with TRCC treated with cabozantinib. The main objectives were to estimate response rate according to RECIST 1.1 and to analyze progression-free survival (PFS) and overall survival (OS). RESULTS: Fifty-two patients with metastatic TRCC treated in the participating centers and evaluable for response were included. Median age at metastatic diagnosis was 40 years (IQR 28.5-53). Patients' IMDC risk groups at diagnosis were favorable (9/52), intermediate (35/52), and poor (8/52). Eleven (21.2%) patients received cabozantinib as frontline therapy, 15 (28.8%) at second line, and 26 (50%) at third line and beyond. The proportion of patients who achieved an objective response was 17.3%, including 2 complete responses and 7 partial responses. For 26 (50%) patients, stable disease was the best response. With a median follow-up of 25.1 months (IQR 12.6-39), median PFS was 6.8 months (95%CI 4.6-16.3) and median OS was 18.3 months (95%CI 17.0-30.6). No difference of response was identified according to fusion transcript features. CONCLUSION: This real-world study provides evidence of the activity of cabozantinib in TRCC, with more durable responses than those observed historically with other VEGFR-TKIs or ICIs.
Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Adulto , Humanos , Pessoa de Meia-Idade , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/genética , Estudos de Coortes , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Estudos RetrospectivosRESUMO
The rarity and inaccessibility of the earliest primordial germ cells (PGCs) in the mouse embryo thwart efforts to investigate molecular mechanisms of germ-cell specification. stella (also called Dppa3) marks the rare founder population of the germ lineage. Here we differentiate mouse embryonic stem cells carrying a stella transgenic reporter into putative PGCs in vitro. The Stella(+) cells possess a transcriptional profile similar to embryo-derived PGCs, and like their counterparts in vivo, lose imprints in a time-dependent manner. Using inhibitory RNAs to screen candidate genes for effects on the development of Stella(+) cells in vitro, we discovered that Lin28, a negative regulator of let-7 microRNA processing, is essential for proper PGC development. Furthermore, we show that Blimp1 (also called Prdm1), a let-7 target and a master regulator of PGC specification, can rescue the effect of Lin28 deficiency during PGC development, thereby establishing a mechanism of action for Lin28 during PGC specification. Overexpression of Lin28 promotes formation of Stella(+) cells in vitro and PGCs in chimaeric embryos, and is associated with human germ-cell tumours. The differentiation of putative PGCs from embryonic stem cells in vitro recapitulates the early stages of gamete development in vivo, and provides an accessible system for discovering novel genes involved in germ-cell development and malignancy.
Assuntos
Diferenciação Celular , Células Germinativas/citologia , Células Germinativas/metabolismo , Neoplasias Embrionárias de Células Germinativas/metabolismo , Neoplasias Embrionárias de Células Germinativas/patologia , Proteínas de Ligação a RNA/metabolismo , Animais , Linhagem Celular , Proteínas Cromossômicas não Histona , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Células Germinativas/patologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Embrionárias de Células Germinativas/genética , Fator 1 de Ligação ao Domínio I Regulador Positivo , Proteínas de Ligação a RNA/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , TransgenesRESUMO
Translocation renal cell carcinoma (tRCC) is an aggressive subtype of kidney cancer driven by TFE3 gene fusions, which act via poorly characterized downstream mechanisms. Here we report that TFE3 fusions transcriptionally rewire tRCCs toward oxidative phosphorylation (OXPHOS), contrasting with the highly glycolytic metabolism of most other renal cancers. This TFE3 fusion-driven OXPHOS program, together with heightened glutathione levels found in renal cancers, renders tRCCs sensitive to reductive stress - a metabolic stress state induced by an imbalance of reducing equivalents. Genome-scale CRISPR screening identifies tRCC-selective vulnerabilities linked to this metabolic state, including EGLN1 , which hydroxylates HIF-1α and targets it for proteolysis. Inhibition of EGLN1 compromises tRCC cell growth by stabilizing HIF-1a and promoting metabolic reprogramming away from OXPHOS, thus representing a vulnerability to OXPHOS-dependent tRCC cells. Our study defines a distinctive tRCC-essential metabolic program driven by TFE3 fusions and nominates EGLN1 inhibition as a therapeutic strategy to counteract fusion-induced metabolic rewiring.
RESUMO
Renal cell carcinoma with sarcomatoid differentiation (sRCC) is associated with poor survival and a heightened response to immune checkpoint inhibitors (ICIs). Two major barriers to improving outcomes for sRCC are the limited understanding of its gene regulatory programs and the low diagnostic yield of tumor biopsies due to spatial heterogeneity. Herein, we characterized the epigenomic landscape of sRCC by profiling 107 epigenomic libraries from tissue and plasma samples from 50 patients with RCC and healthy volunteers. By profiling histone modifications and DNA methylation, we identified highly recurrent epigenomic reprogramming enriched in sRCC. Furthermore, CRISPRa experiments implicated the transcription factor FOSL1 in activating sRCC-associated gene regulatory programs, and FOSL1 expression was associated with the response to ICIs in RCC in two randomized clinical trials. Finally, we established a blood-based diagnostic approach using detectable sRCC epigenomic signatures in patient plasma, providing a framework for discovering epigenomic correlates of tumor histology via liquid biopsy.
Assuntos
Carcinoma de Células Renais , Epigenômica , Neoplasias Renais , Humanos , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/metabolismo , Neoplasias Renais/genética , Neoplasias Renais/patologia , Neoplasias Renais/metabolismo , Epigenômica/métodos , Metilação de DNA/genética , Diferenciação Celular , Regulação Neoplásica da Expressão Gênica , Masculino , Feminino , Epigênese Genética , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-fosRESUMO
The success of precision oncology-which aims to match the right therapies to the right patients based on molecular status-is predicated on a robust pipeline of molecular targets against which therapies can be developed. Recent advances in genomics and functional genetics have enabled the unbiased discovery of novel molecular targets at scale. We summarize the promise and challenges in integrating genomic and functional genetic landscapes of cancer to establish the next generation of cancer targets.
RESUMO
Immunotherapy has revolutionized treatment for patients with advanced and metastatic renal cell carcinoma. Nevertheless, many patients do not benefit or eventually relapse, highlighting the need for novel immune targets to overcome primary and acquired resistance. This review discusses 2 strategies currently being investigated: disabling inhibitory stimuli that maintain immunosuppression ("brakes") and priming the immune system to target tumoral cells ("gas pedals"). We explore each class of novel immunotherapy, including the rationale behind it, supporting preclinical and clinical evidence, and limitations.
Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/terapia , Linfócitos T Citotóxicos , Neoplasias Renais/terapia , Receptor de Morte Celular Programada 1 , Recidiva Local de Neoplasia , ImunoterapiaRESUMO
Targeted therapies have revolutionized the treatment of renal cell carcinoma (RCC). The VHL/HIF pathway is responsible for the regulation of oxygen homeostasis and is frequently altered in RCC. Targeting this pathway as well as the mTOR pathway have yielded remarkable advances in the treatment of RCC. Here, we review the most promising novel targeted therapies for the treatment of RCC, including HIF2α, MET, metabolic targeting, and epigenomic reprogramming.
Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Fator A de Crescimento do Endotélio Vascular , Serina-Treonina Quinases TORRESUMO
Xp11 translocation renal cell carcinoma (tRCC) is a female-predominant kidney cancer driven by translocations between the TFE3 gene on chromosome Xp11.2 and partner genes located on either chrX or on autosomes. The rearrangement processes that underlie TFE3 fusions, and whether they are linked to the female sex bias of this cancer, are largely unexplored. Moreover, whether oncogenic TFE3 fusions arise from both the active and inactive X chromosomes in females remains unknown. Here we address these questions by haplotype-specific analyses of whole-genome sequences of 29 tRCC samples from 15 patients and by re-analysis of 145 published tRCC whole-exome sequences. We show that TFE3 fusions universally arise as reciprocal translocations with minimal DNA loss or insertion at paired break ends. Strikingly, we observe a near exact 2:1 female:male ratio in TFE3 fusions arising via X:autosomal translocation (but not via X inversion), which accounts for the female predominance of tRCC. This 2:1 ratio is at least partially attributable to oncogenic fusions involving the inactive X chromosome and is accompanied by partial re-activation of silenced chrX genes on the rearranged chromosome. Our results highlight how somatic alterations involving the X chromosome place unique constraints on tumor initiation and exemplify how genetic rearrangements of the sex chromosomes can underlie cancer sex differences.
RESUMO
A splice variant of the androgen receptor that drives prostate cancer resistance translocates into the nucleus using a different mechanism from the full-length receptor and exhibits distinct molecular properties once inside.
Assuntos
Neoplasias de Próstata Resistentes à Castração , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Neoplasias de Próstata Resistentes à Castração/genética , Isoformas de Proteínas/metabolismo , Splicing de RNA , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismoRESUMO
Expression of the non-coding RNA XIST is essential for initiating X chromosome inactivation (XCI) during early development in female mammals. As the main function of XCI is to enable dosage compensation of chromosome X genes between the sexes, XCI and XIST expression are generally absent in male normal tissues, except in germ cells and in individuals with supernumerary X chromosomes. Via a systematic analysis of public sequencing data of both cancerous and normal tissues, we report that XIST is somatically activated in a subset of male human cancers across diverse lineages. Some of these cancers display hallmarks of XCI, including silencing of gene expression, reduced chromatin accessibility, and increased DNA methylation across chromosome X, suggesting that the developmentally restricted, female-specific program of XCI can be somatically accessed in male cancers.
Assuntos
Neoplasias , RNA Longo não Codificante , Animais , Humanos , Masculino , Feminino , Inativação do Cromossomo X/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Cromossomo X/metabolismo , Mecanismo Genético de Compensação de Dose , Mamíferos/genética , Neoplasias/genéticaRESUMO
The complex genomic landscape of prostate cancer evolves across disease states under therapeutic pressure directed toward inhibiting androgen receptor (AR) signaling. While significantly altered genes in prostate cancer have been extensively defined, there have been fewer systematic analyses of how structural variation shapes the genomic landscape of this disease across disease states. We uniformly characterized structural alterations across 531 localized and 143 metastatic prostate cancers profiled by whole genome sequencing, 125 metastatic samples of which were also profiled via whole transcriptome sequencing. We observed distinct significantly recurrent breakpoints in localized and metastatic castration-resistant prostate cancers (mCRPC), with pervasive alterations in noncoding regions flanking the AR, MYC, FOXA1, and LSAMP genes enriched in mCRPC and TMPRSS2-ERG rearrangements enriched in localized prostate cancer. We defined 9 subclasses of mCRPC based on signatures of structural variation, each associated with distinct genetic features and clinical outcomes. Our results comprehensively define patterns of structural variation in prostate cancer and identify clinically actionable subgroups based on whole genome profiling.
Assuntos
Neoplasias de Próstata Resistentes à Castração , Genômica , Humanos , Masculino , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Sequenciamento Completo do GenomaRESUMO
Androgen receptor (AR) signaling is the central driver of prostate cancer across disease states. While androgen deprivation therapy (ADT) is effective in the initial treatment of prostate cancer, resistance to ADT or to next-generation androgen pathway inhibitors invariably arises, most commonly through the re-activation of the AR axis. Thus, orthogonal approaches to inhibit AR signaling in advanced prostate cancer are essential. Here, via genome-scale CRISPR-Cas9 screening, we identify protein arginine methyltransferase 1 (PRMT1) as a critical mediator of AR expression and signaling. PRMT1 regulates the recruitment of AR to genomic target sites and the inhibition of PRMT1 impairs AR binding at lineage-specific enhancers, leading to decreased expression of key oncogenes, including AR itself. In addition, AR-driven prostate cancer cells are uniquely susceptible to combined AR and PRMT1 inhibition. Our findings implicate PRMT1 as a key regulator of AR output and provide a preclinical framework for co-targeting of AR and PRMT1 in advanced prostate cancer.
Assuntos
Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Antagonistas de Androgênios/farmacologia , Antagonistas de Androgênios/uso terapêutico , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias de Próstata Resistentes à Castração/genética , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Proteínas Repressoras/metabolismo , Transdução de SinaisRESUMO
Translocation renal cell carcinoma (tRCC) is a poorly characterized subtype of kidney cancer driven by MiT/TFE gene fusions. Here, we define the landmarks of tRCC through an integrative analysis of 152 patients with tRCC identified across genomic, clinical trial, and retrospective cohorts. Most tRCCs harbor few somatic alterations apart from MiT/TFE fusions and homozygous deletions at chromosome 9p21.3 (19.2% of cases). Transcriptionally, tRCCs display a heightened NRF2-driven antioxidant response that is associated with resistance to targeted therapies. Consistently, we find that outcomes for patients with tRCC treated with vascular endothelial growth factor receptor inhibitors (VEGFR-TKIs) are worse than those treated with immune checkpoint inhibitors (ICI). Using multiparametric immunofluorescence, we find that the tumors are infiltrated with CD8+ T cells, though the T cells harbor an exhaustion immunophenotype distinct from that of clear cell RCC. Our findings comprehensively define the clinical and molecular features of tRCC and may inspire new therapeutic hypotheses.
Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Fator de Transcrição Associado à Microftalmia/genética , Proteínas de Fusão Oncogênica/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linfócitos T CD8-Positivos/imunologia , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/patologia , Regulação Neoplásica da Expressão Gênica , Fusão Gênica/genética , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Proteínas de Fusão Oncogênica/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidoresRESUMO
Tuberous Sclerosis Complex (TSC) is caused by TSC1 or TSC2 mutations, resulting in hyperactivation of the mechanistic target of rapamycin complex 1 (mTORC1). Transcription factor EB (TFEB), a master regulator of lysosome biogenesis, is negatively regulated by mTORC1 through a RAG GTPase-dependent phosphorylation. Here we show that lysosomal biogenesis is increased in TSC-associated renal tumors, pulmonary lymphangioleiomyomatosis, kidneys from Tsc2+/- mice, and TSC1/2-deficient cells via a TFEB-dependent mechanism. Interestingly, in TSC1/2-deficient cells, TFEB is hypo-phosphorylated at mTORC1-dependent sites, indicating that mTORC1 is unable to phosphorylate TFEB in the absence of the TSC1/2 complex. Importantly, overexpression of folliculin (FLCN), a GTPase activating protein for RAGC, increases TFEB phosphorylation at the mTORC1 sites in TSC2-deficient cells. Overexpression of constitutively active RAGC is sufficient to relocalize TFEB to the cytoplasm. These findings establish the TSC proteins as critical regulators of lysosomal biogenesis via TFEB and RAGC and identify TFEB as a driver of the proliferation of TSC2-deficient cells.
Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Lisossomos/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Biogênese de Organelas , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Carcinoma de Células Renais/patologia , Núcleo Celular/metabolismo , Proliferação de Células , Feminino , Regulação da Expressão Gênica , Células HEK293 , Células HeLa , Humanos , Neoplasias Renais/patologia , Lisossomos/ultraestrutura , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Fosforilação , Fosfosserina/metabolismo , Transporte Proteico , Proteínas Proto-Oncogênicas/metabolismo , Transcrição Gênica , Proteína 2 do Complexo Esclerose Tuberosa/deficiência , Proteínas Supressoras de Tumor/metabolismoRESUMO
Sarcomatoid and rhabdoid (S/R) renal cell carcinoma (RCC) are highly aggressive tumors with limited molecular and clinical characterization. Emerging evidence suggests immune checkpoint inhibitors (ICI) are particularly effective for these tumors, although the biological basis for this property is largely unknown. Here, we evaluate multiple clinical trial and real-world cohorts of S/R RCC to characterize their molecular features, clinical outcomes, and immunologic characteristics. We find that S/R RCC tumors harbor distinctive molecular features that may account for their aggressive behavior, including BAP1 mutations, CDKN2A deletions, and increased expression of MYC transcriptional programs. We show that these tumors are highly responsive to ICI and that they exhibit an immune-inflamed phenotype characterized by immune activation, increased cytotoxic immune infiltration, upregulation of antigen presentation machinery genes, and PD-L1 expression. Our findings build on prior work and shed light on the molecular drivers of aggressivity and responsiveness to ICI of S/R RCC.