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1.
Mol Cell ; 82(13): 2443-2457.e7, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35613620

RESUMO

RAF protein kinases are effectors of the GTP-bound form of small guanosine triphosphatase RAS and function by phosphorylating MEK. We showed here that the expression of ARAF activated RAS in a kinase-independent manner. Binding of ARAF to RAS displaced the GTPase-activating protein NF1 and antagonized NF1-mediated inhibition of RAS. This reduced ERK-dependent inhibition of RAS and increased RAS-GTP. By this mechanism, ARAF regulated the duration and consequences of RTK-induced RAS activation and supported the RAS output of RTK-dependent tumor cells. In human lung cancers with EGFR mutation, amplification of ARAF was associated with acquired resistance to EGFR inhibitors, which was overcome by combining EGFR inhibitors with an inhibitor of the protein tyrosine phosphatase SHP2 to enhance inhibition of nucleotide exchange and RAS activation.


Assuntos
Neurofibromina 1 , Proteínas Proto-Oncogênicas A-raf , Proteínas Ativadoras de ras GTPase , Receptores ErbB/genética , Receptores ErbB/metabolismo , Guanosina Trifosfato/metabolismo , Humanos , Neurofibromina 1/metabolismo , Ligação Proteica , Proteínas Proto-Oncogênicas A-raf/metabolismo , Transdução de Sinais , Proteínas Ativadoras de ras GTPase/metabolismo
2.
Nature ; 616(7958): 806-813, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36991128

RESUMO

Metastasis frequently develops from disseminated cancer cells that remain dormant after the apparently successful treatment of a primary tumour. These cells fluctuate between an immune-evasive quiescent state and a proliferative state liable to immune-mediated elimination1-6. Little is known about the clearing of reawakened metastatic cells and how this process could be therapeutically activated to eliminate residual disease in patients. Here we use models of indolent lung adenocarcinoma metastasis to identify cancer cell-intrinsic determinants of immune reactivity during exit from dormancy. Genetic screens of tumour-intrinsic immune regulators identified the stimulator of interferon genes (STING) pathway as a suppressor of metastatic outbreak. STING activity increases in metastatic progenitors that re-enter the cell cycle and is dampened by hypermethylation of the STING promoter and enhancer in breakthrough metastases or by chromatin repression in cells re-entering dormancy in response to TGFß. STING expression in cancer cells derived from spontaneous metastases suppresses their outgrowth. Systemic treatment of mice with STING agonists eliminates dormant metastasis and prevents spontaneous outbreaks in a T cell- and natural killer cell-dependent manner-these effects require cancer cell STING function. Thus, STING provides a checkpoint against the progression of dormant metastasis and a therapeutically actionable strategy for the prevention of disease relapse.


Assuntos
Neoplasias Pulmonares , Metástase Neoplásica , Animais , Camundongos , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/patologia , Ciclo Celular , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/genética , Metástase Neoplásica/imunologia , Metástase Neoplásica/patologia , Recidiva Local de Neoplasia/tratamento farmacológico , Linfócitos T/imunologia , Fator de Crescimento Transformador beta , Células Matadoras Naturais/imunologia
3.
Oncologist ; 29(1): 15-24, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37616543

RESUMO

BACKGROUND: Cancers with non-V600 BRAF-activating alterations have no matched therapy. Preclinical data suggest that these tumors depend on ERK signaling; however, clinical response to MEK/ERK inhibitors has overall been low. We hypothesized that a narrow therapeutic index, driven by ERK inhibition in healthy (wild-type) tissues, limits the efficacy of these inhibitors. As these mutants signal as activated dimers, we further hypothesized that RAF inhibitors given concurrently would improve the therapeutic index by opposing ERK inhibition in normal tissues and not activate ERK in the already activated tumor. MATERIALS AND METHODS: Using cell lines and patient-derived xenografts, we evaluated the effect of RAF inhibition, alone and in combination with MEK/ERK inhibitors. We then undertook a phase I/II clinical trial of a higher dose of the MEK inhibitor binimetinib combined with the RAF inhibitor encorafenib in patients with advanced cancer with activating non-V600 BRAF alterations. RESULTS: RAF inhibition led to modest inhibition of signaling and growth in activated non-V600 BRAF preclinical models and allowed higher dose of MEK/ERK inhibitors in vivo for more profound tumor regression. Fifteen patients received binimetinib 60 mg twice daily plus encorafenib 450 mg daily (6 gastrointestinal primaries, 6 genitourinary primaries, 3 melanoma, and 2 lung cancer; 7 BRAF mutations and 8 BRAF fusions). Treatment was well tolerated without dose-limiting toxicities. One patient had a confirmed partial response, 8 had stable disease, and 6 had radiographic or clinical progression as best response. On-treatment biopsies revealed incomplete ERK pathway inhibition. CONCLUSION: Combined RAF and MEK inhibition does not sufficiently inhibit activated non-V600 BRAF-mutant tumors in patients.


Assuntos
Melanoma , Proteínas Proto-Oncogênicas B-raf , Humanos , Proteínas Proto-Oncogênicas B-raf/genética , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Melanoma/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Quinases de Proteína Quinase Ativadas por Mitógeno , Mutação
4.
Proc Natl Acad Sci U S A ; 118(32)2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34353917

RESUMO

The increasing complexity of different cell types revealed by single-cell analysis of tissues presents challenges in efficiently elucidating their functions. Here we show, using prostate as a model tissue, that primary organoids and freshly isolated epithelial cells can be CRISPR edited ex vivo using Cas9-sgRNA (guide RNA) ribotnucleoprotein complex technology, then orthotopically transferred in vivo into immunocompetent or immunodeficient mice to generate cancer models with phenotypes resembling those seen in traditional genetically engineered mouse models. Large intrachromosomal (∼2 Mb) or multigenic deletions can be engineered efficiently without the need for selection, including in isolated subpopulations to address cell-of-origin questions.


Assuntos
Deleção Cromossômica , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Edição de Genes/métodos , Próstata/citologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteína 9 Associada à CRISPR/genética , Células Epiteliais , Genes Supressores de Tumor , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Organoides , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , RNA Guia de Cinetoplastídeos , Ribonucleoproteínas/genética , Regulador Transcricional ERG/genética , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Nature ; 548(7666): 234-238, 2017 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-28783719

RESUMO

Approximately 200 BRAF mutant alleles have been identified in human tumours. Activating BRAF mutants cause feedback inhibition of GTP-bound RAS, are RAS-independent and signal either as active monomers (class 1) or constitutively active dimers (class 2). Here we characterize a third class of BRAF mutants-those that have impaired kinase activity or are kinase-dead. These mutants are sensitive to ERK-mediated feedback and their activation of signalling is RAS-dependent. The mutants bind more tightly than wild-type BRAF to RAS-GTP, and their binding to and activation of wild-type CRAF is enhanced, leading to increased ERK signalling. The model suggests that dysregulation of signalling by these mutants in tumours requires coexistent mechanisms for maintaining RAS activation despite ERK-dependent feedback. Consistent with this hypothesis, melanomas with these class 3 BRAF mutations also harbour RAS mutations or NF1 deletions. By contrast, in lung and colorectal cancers with class 3 BRAF mutants, RAS is typically activated by receptor tyrosine kinase signalling. These tumours are sensitive to the inhibition of RAS activation by inhibitors of receptor tyrosine kinases. We have thus defined three distinct functional classes of BRAF mutants in human tumours. The mutants activate ERK signalling by different mechanisms that dictate their sensitivity to therapeutic inhibitors of the pathway.


Assuntos
Melanoma/enzimologia , Melanoma/genética , Mutação , Proteína Oncogênica p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Animais , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Indóis/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Células NIH 3T3 , Neurofibromatose 1/genética , Proteína Oncogênica p21(ras)/metabolismo , Multimerização Proteica , Piridonas/farmacologia , Pirimidinonas/farmacologia , Sulfonamidas/farmacologia , Vemurafenib , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Nature ; 531(7592): 105-9, 2016 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-26863197

RESUMO

The enteric nervous system (ENS) is the largest component of the autonomic nervous system, with neuron numbers surpassing those present in the spinal cord. The ENS has been called the 'second brain' given its autonomy, remarkable neurotransmitter diversity and complex cytoarchitecture. Defects in ENS development are responsible for many human disorders including Hirschsprung disease (HSCR). HSCR is caused by the developmental failure of ENS progenitors to migrate into the gastrointestinal tract, particularly the distal colon. Human ENS development remains poorly understood owing to the lack of an easily accessible model system. Here we demonstrate the efficient derivation and isolation of ENS progenitors from human pluripotent stem (PS) cells, and their further differentiation into functional enteric neurons. ENS precursors derived in vitro are capable of targeted migration in the developing chick embryo and extensive colonization of the adult mouse colon. The in vivo engraftment and migration of human PS-cell-derived ENS precursors rescue disease-related mortality in HSCR mice (Ednrb(s-l/s-l)), although the mechanism of action remains unclear. Finally, EDNRB-null mutant ENS precursors enable modelling of HSCR-related migration defects, and the identification of pepstatin A as a candidate therapeutic target. Our study establishes the first, to our knowledge, human PS-cell-based platform for the study of human ENS development, and presents cell- and drug-based strategies for the treatment of HSCR.


Assuntos
Linhagem da Célula , Terapia Baseada em Transplante de Células e Tecidos , Descoberta de Drogas/métodos , Sistema Nervoso Entérico/patologia , Doença de Hirschsprung/tratamento farmacológico , Doença de Hirschsprung/patologia , Neurônios/patologia , Envelhecimento , Animais , Diferenciação Celular , Linhagem Celular , Movimento Celular , Separação Celular , Terapia Baseada em Transplante de Células e Tecidos/métodos , Embrião de Galinha , Colo/efeitos dos fármacos , Colo/patologia , Modelos Animais de Doenças , Feminino , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/patologia , Doença de Hirschsprung/terapia , Humanos , Masculino , Camundongos , Neurônios/efeitos dos fármacos , Pepstatinas/metabolismo , Células-Tronco Pluripotentes/patologia , Receptor de Endotelina B/metabolismo , Transdução de Sinais
7.
bioRxiv ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38585869

RESUMO

To gain insight into how ERG translocations cause prostate cancer, we performed single cell transcriptional profiling of an autochthonous mouse model at an early stage of disease initiation. Despite broad expression of ERG in all prostate epithelial cells, proliferation was enriched in a small, stem-like population with mixed-luminal basal identity (called intermediate cells). Through a series of lineage tracing and primary prostate tissue transplantation experiments, we find that tumor initiating activity resides in a subpopulation of basal cells that co-express the luminal genes Tmprss2 and Nkx3.1 (called BasalLum) but not in the larger population of classical Krt8+ luminal cells. Upon ERG activation, BasalLum cells give rise to the highly proliferative intermediate state, which subsequently transitions to the larger population of Krt8+ luminal cells characteristic of ERG-positive human cancers. Furthermore, this proliferative population is characterized by an ERG-specific chromatin state enriched for NFkB, AP-1, STAT and NFAT binding, with implications for TF cooperativity. The fact that the proliferative potential of ERG is enriched in a small stem-like population implicates the chromatin context of these cells as a critical variable for unmasking its oncogenic activity.

8.
bioRxiv ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38645223

RESUMO

Lineage plasticity is a recognized hallmark of cancer progression that can shape therapy outcomes. The underlying cellular and molecular mechanisms mediating lineage plasticity remain poorly understood. Here, we describe a versatile in vivo platform to identify and interrogate the molecular determinants of neuroendocrine lineage transformation at different stages of prostate cancer progression. Adenocarcinomas reliably develop following orthotopic transplantation of primary mouse prostate organoids acutely engineered with human-relevant driver alterations (e.g., Rb1-/-; Trp53-/-; cMyc+ or Pten-/-; Trp53-/-; cMyc+), but only those with Rb1 deletion progress to ASCL1+ neuroendocrine prostate cancer (NEPC), a highly aggressive, androgen receptor signaling inhibitor (ARSI)-resistant tumor. Importantly, we show this lineage transition requires a native in vivo microenvironment not replicated by conventional organoid culture. By integrating multiplexed immunofluorescence, spatial transcriptomics and PrismSpot to identify cell type-specific spatial gene modules, we reveal that ASCL1+ cells arise from KRT8+ luminal epithelial cells that progressively acquire transcriptional heterogeneity, producing large ASCL1+;KRT8- NEPC clusters. Ascl1 loss in established NEPC results in transient tumor regression followed by recurrence; however, Ascl1 deletion prior to transplantation completely abrogates lineage plasticity, yielding adenocarcinomas with elevated AR expression and marked sensitivity to castration. The dynamic feature of this model reveals the importance of timing of therapies focused on lineage plasticity and offers a platform for identification of additional lineage plasticity drivers.

9.
Nat Cancer ; 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39394434

RESUMO

Lineage plasticity is a hallmark of cancer progression that impacts therapy outcomes, yet the mechanisms mediating this process remain unclear. Here, we introduce a versatile in vivo platform to interrogate neuroendocrine lineage transformation throughout prostate cancer progression. Transplanted mouse prostate organoids with human-relevant driver mutations (Rb1-/-; Trp53-/-; cMyc+ or Pten-/-; Trp53-/-; cMyc+) develop adenocarcinomas, but only those with Rb1 deletion advance to aggressive, ASCL1+ neuroendocrine prostate cancer (NEPC) resistant to androgen receptor signaling inhibitors. Notably, this transition requires an in vivo microenvironment not replicated by conventional organoid culture. Using multiplexed immunofluorescence and spatial transcriptomics, we reveal that ASCL1+ cells arise from KRT8+ luminal cells, progressing into transcriptionally heterogeneous ASCL1+;KRT8- NEPC. Ascl1 loss in established NEPC causes transient regression followed by recurrence, but its deletion before transplantation abrogates lineage plasticity, resulting in castration-sensitive adenocarcinomas. This dynamic model highlights the importance of therapy timing and offers a platform to identify additional lineage plasticity drivers.

10.
Neoplasia ; 40: 100900, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37058885

RESUMO

Tumor heterogeneity dominates tumor biological behavior and shapes the tumor microenvironment. However, the mechanisms of tumor genetic features modulate immunity response were not clearly clarified. Tumor associated macrophages (TAMs) exert distinct immune functions in the progression of hepatocellular carcinoma (HCC) based on the inducible phenotype. FOXO family members sense changes in the extracellular or intracellular environment by activating a series of signaling pathways. FOXO1, a transcription factor that a common suppressor in hepatocellular carcinoma, correlated with a better tumor biological behavior in HCC through shaping macrophages anti-tumour response. Here, we found that human HCC tissue microarray (TMA) slides were employed to showed tumor derived FOXO1 negatively related with distribution of protumour macrophages. This phenomenon was confirmed in mouse xenograft model and in vitro. HCC-derived FOXO1 inhibits tumorigenesis not only by targeting tumor cells but also by synchronizing with re-educated macrophages. These effects may be partially dependent on FOXO1 transcriptionally modulates IRF-1/nitrio oxide (NO) axis in exerting effects in macrophages and decreasing IL-6 releasing from macrophages in tumor microenvironment indirectly. This feedback suppressed the progression of HCC by inactivation of IL-6/STAT3 in HCC. It implicates the potential role of FOXO1 in the therapeutic effects for modulating immune response by targeting macrophages.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Neoplasias Hepáticas/metabolismo , Macrófagos/metabolismo , Transdução de Sinais , Microambiente Tumoral/genética
11.
Cell Death Discov ; 9(1): 120, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37037815

RESUMO

Inflammation is a core mechanism for oncogenesis. Chemokines act as important mediators of chronic inflammation and the tumour inflammatory response. However, there is limited information on chemokines in hepatocellular carcinoma (HCC), a disease for which almost all cases are derived from chronic liver inflammation. Here, we explored the protumor effects of CXCL1, a commonly elevated inflammatory chemokine in cirrhosis, in HCC. The protumor role was confirmed in clinical samples from HCC patients. CXCL1 enhanced tumorigenesis in the hepatic inflammatory microenvironment directly by acting on tumour cells and indirectly through promoting the recruitment of macrophages. The increase in the number of macrophages in the tumour microenvironment (TME) promoted tumour cell epithelial-mesenchymal transition (EMT) and significantly increased CXCL1 levels in the TME partly through NF-κB/IL-1ß activation. To investigate the potential therapeutic value of CXCL1 in HCC with an inflammatory background, an antibody blocking CXCL1 was used alone or combined with the chemotherapy agent doxorubicin (DOX), with the goal of reshaping the TME. It has been shown that blocking CXCL1-CXCR2 inhibits tumour progression and reduces macrophage recruitment in the TME. The combination regimen has been shown to synergistically reduce the number of pro-tumour macrophages in the TME and suppress tumour progression. This provides insight into therapeutic strategies for treating HCC patients with high CXCL1 expression.

12.
Cell Stem Cell ; 30(3): 264-282.e9, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36868194

RESUMO

The enteric nervous system (ENS) is derived from both the vagal and sacral component of the neural crest (NC). Here, we present the derivation of sacral ENS precursors from human PSCs via timed exposure to FGF, WNT, and GDF11, which enables posterior patterning and transition from posterior trunk to sacral NC identity, respectively. Using a SOX2::H2B-tdTomato/T::H2B-GFP dual reporter hPSC line, we demonstrate that both trunk and sacral NC emerge from a double-positive neuro-mesodermal progenitor (NMP). Vagal and sacral NC precursors yield distinct neuronal subtypes and migratory behaviors in vitro and in vivo. Remarkably, xenografting of both vagal and sacral NC lineages is required to rescue a mouse model of total aganglionosis, suggesting opportunities in the treatment of severe forms of Hirschsprung's disease.


Assuntos
Doença de Hirschsprung , Animais , Humanos , Camundongos , Proteínas Morfogenéticas Ósseas , Modelos Animais de Doenças , Fatores de Diferenciação de Crescimento , Xenoenxertos , Histonas , Crista Neural
13.
Cancer Discov ; 13(1): 41-55, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36355783

RESUMO

With the combination of KRASG12C and EGFR inhibitors, KRAS is becoming a druggable target in colorectal cancer. However, secondary resistance limits its efficacy. Using cell lines, patient-derived xenografts, and patient samples, we detected a heterogeneous pattern of putative resistance alterations expected primarily to prevent inhibition of ERK signaling by drugs at progression. Serial analysis of patient blood samples on treatment demonstrates that most of these alterations are detected at a low frequency except for KRASG12C amplification, a recurrent resistance mechanism that rises in step with clinical progression. Upon drug withdrawal, resistant cells with KRASG12C amplification undergo oncogene-induced senescence, and progressing patients experience a rapid fall in levels of this alteration in circulating DNA. In this new state, drug resumption is ineffective as mTOR signaling is elevated. However, our work exposes a potential therapeutic vulnerability, whereby therapies that target the senescence response may overcome acquired resistance. SIGNIFICANCE: Clinical resistance to KRASG12C-EGFR inhibition primarily prevents suppression of ERK signaling. Most resistance mechanisms are subclonal, whereas KRASG12C amplification rises over time to drive a higher portion of resistance. This recurrent resistance mechanism leads to oncogene-induced senescence upon drug withdrawal and creates a potential vulnerability to senolytic approaches. This article is highlighted in the In This Issue feature, p. 1.


Assuntos
Neoplasias Colorretais , Resistencia a Medicamentos Antineoplásicos , Animais , Humanos , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Transdução de Sinais , Modelos Animais de Doenças , Receptores ErbB , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Mutação
14.
Mol Cancer Ther ; 21(2): 382-394, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34789562

RESUMO

Hurthle cell carcinomas (HCCs) are refractory to radioactive iodine and unresponsive to chemotherapeutic agents, with a fatality rate that is the highest among all types of thyroid cancer after anaplastic thyroid cancer. Our previous study on the genomic landscape of HCCs identified a high incidence of disruptions of mTOR pathway effectors. Here, we report a detailed analysis of mTOR signaling in cell line and patient-derived xenograft mouse models of HCCs. We show that mTOR signaling is upregulated and that targeting mTOR signaling using mTOR inhibitors suppresses tumor growth in primary tumors and distant metastasis. Mechanistically, ablation of mTOR signaling impaired the expression of p-S6 and cyclin A2, resulting in the decrease of the S phase and blocking of cancer cell proliferation. Strikingly, mTOR inhibitor treatment significantly reduced lung metastatic lesions, with the decreased expression of Snail in xenograft tumors. Our data demonstrate that mTOR pathway blockade represents a novel treatment strategy for HCC.


Assuntos
Adenoma Oxífilo/genética , Neoplasias/genética , Serina-Treonina Quinases TOR/genética , Neoplasias da Glândula Tireoide/genética , Adenoma Oxífilo/patologia , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos SCID , Neoplasias/patologia , Neoplasias da Glândula Tireoide/patologia
15.
Clin Cancer Res ; 28(5): 948-959, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34907079

RESUMO

PURPOSE: Advances in our understanding of the contribution of aberrant glycosylation to the pro-oncogenic signaling and metastasis of tumor cells have reinvigorated the development of mucin-targeted therapies. Here, we validate the tumor-targeting ability of a novel monoclonal antibody (mAb), AR9.6, that binds MUC16 and abrogates downstream oncogenic signaling to confer a therapeutic response. EXPERIMENTAL DESIGN: The in vitro and ex vivo validation of the binding of AR9.6 to MUC16 was achieved via flow cytometry, radioligand binding assay (RBA), and immunohistochemistry (IHC). The in vivo MUC16 targeting of AR9.6 was validated by creating a 89Zr-labeled radioimmunoconjugate of the mAb and utilizing immunoPET and ex vivo biodistribution studies in xenograft models of human ovarian and pancreatic cancer. RESULTS: Flow cytometry, RBA, and IHC revealed that AR9.6 binds to ovarian and pancreatic cancer cells in an MUC16-dependent manner. The in vivo radiopharmacologic profile of 89Zr-labeled AR9.6 in mice bearing ovarian and pancreatic cancer xenografts confirmed the MUC16-dependent tumor targeting by the radioimmunoconjugate. Radioactivity uptake was also observed in the distant lymph nodes (LNs) of mice bearing xenografts with high levels of MUC16 expression (i.e., OVCAR3 and Capan-2). IHC analyses of these PET-positive LNs highlighted the presence of shed antigen as well as necrotic, phagocytized, and actively infiltrating neoplastic cells. The humanization of AR9.6 did not compromise its ability to target MUC16-expressing tumors. CONCLUSIONS: The unique therapeutic mechanism of AR9.6 combined with its excellent in vivo tumor targeting makes it a highly promising theranostic agent. huAR9.6 is poised for clinical translation to impact the management of metastatic ovarian and pancreatic cancers.


Assuntos
Imunoconjugados , Neoplasias Ovarianas , Neoplasias Pancreáticas , Animais , Anticorpos Monoclonais/farmacologia , Apoptose , Antígeno Ca-125 , Carcinogênese , Linhagem Celular Tumoral , Feminino , Humanos , Imunoconjugados/uso terapêutico , Proteínas de Membrana/metabolismo , Camundongos , Mucinas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Radioisótopos/uso terapêutico , Distribuição Tecidual , Zircônio , Neoplasias Pancreáticas
16.
Oncogene ; 41(5): 671-682, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34802033

RESUMO

Chromosome 8q gain is associated with poor clinical outcomes in prostate cancer, but the underlying biological mechanisms remain to be clarified. CSN5, a putative androgen receptor (AR) partner that is located on chromosome 8q, is the key subunit of the COP9 signalosome, which deactivates ubiquitin ligases. Deregulation of CSN5 could affect diverse cellular functions that contribute to tumor development, but there has been no comprehensive study of its function in prostate cancer. The clinical significance of CSN5 amplification/overexpression was evaluated in 16 prostate cancer clinical cohorts. Its oncogenic activity was assessed by genetic and pharmacologic perturbations of CSN5 activity in prostate cancer cell lines. The molecular mechanisms of CSN5 function were assessed, as was the efficacy of the CSN5 inhibitor CSN5i-3 in vitro and in vivo. Finally, the transcription cofactor activity of CSN5 in prostate cancer cells was determined. The prognostic significance of CSN5 amplification and overexpression in prostate cancer was independent of MYC amplification. Inhibition of CSN5 inhibited its oncogenic function by targeting AR signaling, DNA repair, multiple oncogenic pathways, and spliceosome regulation. Furthermore, inhibition of CSN5 repressed metabolic pathways, including oxidative phosphorylation and glycolysis in AR-negative prostate cancer cells. Targeting CSN5 with CSN5i-3 showed potent antitumor activity in vitro and in vivo. Importantly, CSN5i-3 synergizes with PARP inhibitors to inhibit prostate cancer cell growth. CSN5 functions as a transcription cofactor to cooperate with multiple transcription factors in prostate cancer. Inhibiting CSN5 strongly attenuates prostate cancer progression and could enhance PARP inhibition efficacy in the treatment of prostate cancer.


Assuntos
Complexo do Signalossomo COP9
17.
Sci Rep ; 11(1): 22515, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34795358

RESUMO

The rotational hydraulic damper has advantages in the design and control of rotational machines. This paper presents a novel hydraulic rotational damper with the characteristic of adjusting the damping coefficient. It is composed of a shell, a gap, a rotor shaft, sliding vanes, a valve, and a motor, just like a combination of a sliding pump system and a valve driven by a motor. A new cam ring slot designed to guide the radial motion of sliding vanes could reduce friction resistance force, which will also benefit the design of the sliding pump. The damping coefficient model of this damper is established based on dynamic analysis. Series of numerical simulations validate the impact of factors on the damping coefficient. Frictional resistances have little influence on the damping coefficient during most conditions. The total coefficient is positively correlative with the angular velocity and the valve angle. Therefore, changing the valve angle according to the rotor shaft's angular speed could adjust the damping coefficient.

18.
Clin Res Hepatol Gastroenterol ; 45(5): 101712, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33930594

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common tumours worldwide, and identifying markers related to HCC is an important area of research. As a microRNA (miRNA), miRNA125b (miR-125b) plays an important role in the prediction and prognosis of HCC. In the past 10 years, with increasing research on miR-125b and HCC, the molecular mechanism of its relationship with the development of HCC has been elucidated. MiR-125b inhibits the development of HCC and is highly accurate in predicting HCC and is therefore a valuable predictive marker of HCC. This article summarizes the clinical application of miR-125b in HCC and the potential mechanism of its involvement in the progression of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Progressão da Doença , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , MicroRNAs/genética , MicroRNAs/metabolismo
19.
Cell Rep ; 37(3): 109870, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34686346

RESUMO

FBXO31 is the substrate receptor of one of many CUL1-RING ubiquitin ligase (CRL1) complexes. Here, we show that low FBXO31 mRNA levels are associated with high pre-operative prostate-specific antigen (PSA) levels and Gleason grade in human prostate cancer. Mechanistically, the ubiquitin ligase CRL1FBXO31 promotes the ubiquitylation-mediated degradation of DUSP6, a dual specificity phosphatase that dephosphorylates and inactivates the extracellular-signal-regulated kinase-1 and -2 (ERK1/2). Depletion of FBXO31 stabilizes DUSP6, suppresses ERK signaling, and activates the PI3K-AKT signaling cascade. Moreover, deletion of FBXO31 promotes tumor development in a mouse orthotopic model of prostate cancer. Treatment with BCI, a small molecule inhibitor of DUSP6, suppresses AKT activation and prevents tumor formation, suggesting that the FBXO31 tumor suppressor activity is dependent on DUSP6. Taken together, our studies highlight the relevance of the FBXO31-DUSP6 axis in the regulation of ERK- and PI3K-AKT-mediated signaling pathways, as well as its therapeutic potential in prostate cancer.


Assuntos
Fosfatase 6 de Especificidade Dupla/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteínas F-Box/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Neoplasias da Próstata/enzimologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proteínas Culina/genética , Proteínas Culina/metabolismo , Cicloexilaminas/farmacologia , Fosfatase 6 de Especificidade Dupla/antagonistas & inibidores , Fosfatase 6 de Especificidade Dupla/genética , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Estabilidade Enzimática , Proteínas F-Box/genética , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Indenos/farmacologia , Masculino , Camundongos Endogâmicos NOD , Camundongos SCID , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Proteólise , Transdução de Sinais , Proteínas Supressoras de Tumor/genética , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Mol Ther Oncolytics ; 17: 169-179, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32346607

RESUMO

Despite intensive efforts, a considerable proportion of colorectal cancer (CRC) patients develop local recurrence and distant metastasis. Stomatin-like protein 2 (SLP-2), a member of the highly conserved stomatin superfamily, is upregulated across cancer types. However, the biological and functional roles of SLP-2 remain elusive in CRC. Here, we report that high SLP-2 expression was found in CRC tissues and was linked to tumor progression and tumor cell differentiation. Additionally, high SLP-2 expression correlated with poor overall survival (OS) in CRC patients (p < 0.001). SLP-2 knockout (SLP-2KO), generated by CRISPR/Cas9, reduced cell growth, migration, and invasion; induced apoptosis in CRC cells; and reduced tumor xenograft growth in vivo. A 181-compound library screening showed that SLP-2KO produced resistance to JAK2 inhibitors (NVP-BSK805 and TG-101348) and a PIM1 inhibitor (SGI-1776), revealing that the JAK2-STAT3-PIM1 oncogenic pathway was potentially controlled by SLP-2 in CRC. In vitro and in vivo, TG-101348 combined with SGI-1776 was synergistic in CRC (combination index [CI] < 1). Overall, our findings suggest that SLP-2 controls the JAK2-STAT3-PIM1 oncogenic pathway, offering a rationale for a novel therapeutic strategy with combined SGI-1776 and TG-101348 in CRC. Additionally, SLP-2 may be a prognostic marker and biomarker for sensitivity to JAK2 and PIM1 inhibitors.

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