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1.
Nature ; 537(7618): 102-106, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27556950

RESUMO

Circulating tumour cells in women with advanced oestrogen-receptor (ER)-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer acquire a HER2-positive subpopulation after multiple courses of therapy. In contrast to HER2-amplified primary breast cancer, which is highly sensitive to HER2-targeted therapy, the clinical significance of acquired HER2 heterogeneity during the evolution of metastatic breast cancer is unknown. Here we analyse circulating tumour cells from 19 women with ER+/HER2- primary tumours, 84% of whom had acquired circulating tumour cells expressing HER2. Cultured circulating tumour cells maintain discrete HER2+ and HER2- subpopulations: HER2+ circulating tumour cells are more proliferative but not addicted to HER2, consistent with activation of multiple signalling pathways; HER2- circulating tumour cells show activation of Notch and DNA damage pathways, exhibiting resistance to cytotoxic chemotherapy, but sensitivity to Notch inhibition. HER2+ and HER2- circulating tumour cells interconvert spontaneously, with cells of one phenotype producing daughters of the opposite within four cell doublings. Although HER2+ and HER2- circulating tumour cells have comparable tumour initiating potential, differential proliferation favours the HER2+ state, while oxidative stress or cytotoxic chemotherapy enhances transition to the HER2- phenotype. Simultaneous treatment with paclitaxel and Notch inhibitors achieves sustained suppression of tumorigenesis in orthotopic circulating tumour cell-derived tumour models. Together, these results point to distinct yet interconverting phenotypes within patient-derived circulating tumour cells, contributing to progression of breast cancer and acquisition of drug resistance.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patologia , Receptor ErbB-2/metabolismo , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Células Neoplásicas Circulantes/efeitos dos fármacos , Fenótipo , Receptor ErbB-2/deficiência , Receptor Notch1/antagonistas & inibidores , Receptor Notch1/metabolismo , Transdução de Sinais
2.
Breast Cancer Res Treat ; 188(1): 43-52, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34101078

RESUMO

PURPOSE: Therapeutic efficacy of hormonal therapies to target estrogen receptor (ER)-positive breast cancer is limited by the acquisition of ligand-independent ESR1 mutations, which confer treatment resistance to aromatase inhibitors (AIs). Monitoring for the emergence of such mutations may enable individualized therapy. We thus assessed CTC- and ctDNA-based detection of ESR1 mutations with the aim of evaluating non-invasive approaches for the determination of endocrine resistance. PATIENTS AND METHODS: In a prospective cohort of 55 women with hormone receptor-positive metastatic breast cancer, we isolated circulating tumor cells (CTCs) and developed a high-sensitivity method for the detection of ESR1 mutations in these CTCs. In patients with sufficient plasma for the simultaneous extraction of circulating tumor DNA (ctDNA), we performed a parallel analysis of ESR1 mutations using multiplex droplet digital PCR (ddPCR) and examined the agreement between these two platforms. Finally, we isolated single CTCs from a subset of these patients and reviewed RNA expression to explore alternate methods of evaluating endocrine responsiveness. RESULTS: High-sensitivity ESR1 sequencing from CTCs revealed mono- and oligoclonal mutations in 22% of patients. These were concordant with plasma DNA sequencing in 95% of cases. Emergence of ESR1 mutations was correlated both with time to metastatic relapse and duration of AI therapy following such recurrence. The Presence of an ESR1 mutation, compared to ESR1 wild type, was associated with markedly shorter Progression-Free Survival on AI-based therapies (p = 0.0006), but unaltered to other non-AI-based therapies (p = 0.73). Compared with ESR1 mutant cases, AI-resistant CTCs with wild-type ESR1 showed an elevated ER-coactivator RNA signature, consistent with their predicted response to second-line hormonal therapies. CONCLUSION: Blood-based serial monitoring may guide the selection of precision therapeutics for women with AI-resistant ER-positive breast cancer.


Assuntos
Neoplasias da Mama , DNA Tumoral Circulante , Células Neoplásicas Circulantes , Receptor alfa de Estrogênio/genética , Feminino , Genótipo , Humanos , Mutação , Recidiva Local de Neoplasia , Estudos Prospectivos
3.
Nat Methods ; 12(7): 685-91, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25984697

RESUMO

Cancer cells metastasize through the bloodstream either as single migratory circulating tumor cells (CTCs) or as multicellular groupings (CTC clusters). Existing technologies for CTC enrichment are designed to isolate single CTCs, and although CTC clusters are detectable in some cases, their true prevalence and significance remain to be determined. Here we developed a microchip technology (the Cluster-Chip) to capture CTC clusters independently of tumor-specific markers from unprocessed blood. CTC clusters are isolated through specialized bifurcating traps under low-shear stress conditions that preserve their integrity, and even two-cell clusters are captured efficiently. Using the Cluster-Chip, we identified CTC clusters in 30-40% of patients with metastatic breast or prostate cancer or with melanoma. RNA sequencing of CTC clusters confirmed their tumor origin and identified tissue-derived macrophages within the clusters. Efficient capture of CTC clusters will enable the detailed characterization of their biological properties and role in metastasis.


Assuntos
Técnicas Analíticas Microfluídicas , Células Neoplásicas Circulantes , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Imuno-Histoquímica , Masculino , Neoplasias da Próstata/patologia , Análise de Sequência de RNA
4.
Nat Commun ; 14(1): 4317, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37463915

RESUMO

Patients with pancreatic cancer commonly develop weight loss and muscle wasting. Whether adipose tissue and skeletal muscle losses begin before diagnosis and the potential utility of such losses for earlier cancer detection are not well understood. We quantify skeletal muscle and adipose tissue areas from computed tomography (CT) imaging obtained 2 months to 5 years before cancer diagnosis in 714 pancreatic cancer cases and 1748 matched controls. Adipose tissue loss is identified up to 6 months, and skeletal muscle wasting is identified up to 18 months before the clinical diagnosis of pancreatic cancer and is not present in the matched control population. Tissue losses are of similar magnitude in cases diagnosed with localized compared with metastatic disease and are not correlated with at-diagnosis circulating levels of CA19-9. Skeletal muscle wasting occurs in the 1-2 years before pancreatic cancer diagnosis and may signal an upcoming diagnosis of pancreatic cancer.


Assuntos
Composição Corporal , Neoplasias Pancreáticas , Humanos , Tecido Adiposo/metabolismo , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/metabolismo , Atrofia Muscular/patologia , Músculo Esquelético/metabolismo , Caquexia/diagnóstico , Caquexia/etiologia , Caquexia/metabolismo , Neoplasias Pancreáticas
6.
Cancer Epidemiol Biomarkers Prev ; 28(12): 2062-2069, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31533940

RESUMO

BACKGROUND: Pancreatic cancer is associated with development of cachexia, a wasting syndrome thought to limit survival. Few studies have longitudinally quantified peripheral tissues or identified biomarkers predictive of future tissue wasting. METHODS: Adipose and muscle tissue were measured by computed tomography (CT) at diagnosis and 50 to 120 days later in 164 patients with advanced pancreatic cancer. Tissue changes and survival were evaluated by Cox proportional hazards regression. Baseline levels of circulating markers were examined in relation to future tissue wasting. RESULTS: Compared with patients in the bottom quartile of muscle change per 30 days (average gain of 0.8 ± 2.0 cm2), those in the top quartile (average loss of 12.9 ± 4.9 cm2) had a hazard ratio (HR) for death of 2.01 [95% confidence interval (CI), 1.12-3.62]. Patients in the top quartile of muscle attenuation change (average decrease of 4.9 ± 2.4 Hounsfield units) had an HR of 2.19 (95% CI, 1.18-4.04) compared with those in the bottom quartile (average increase of 2.4 ± 1.6 Hounsfield units). Changes in adipose tissue were not associated with survival. Higher plasma branched chain amino acids (BCAA; P = 0.004) and lower monocyte chemoattractant protein-1 (MCP-1; P = 0.005) at diagnosis were associated with greater future muscle loss. CONCLUSIONS: In patients with advanced pancreatic cancer, muscle loss and decrease in muscle density in 2 to 4 months after diagnosis were associated with reduced survival. BCAAs and MCP-1 levels at diagnosis were associated with subsequent muscle loss. IMPACT: BCAAs and MCP-1 levels at diagnosis could identify a high-risk group for future tissue wasting.


Assuntos
Tecido Adiposo/fisiopatologia , Composição Corporal , Músculo Esquelético/fisiopatologia , Neoplasias Pancreáticas/mortalidade , Tomografia Computadorizada por Raios X/métodos , Tecido Adiposo/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
7.
Carcinogenesis ; 29(5): 918-25, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18359760

RESUMO

The Notch pathway plays a key role in the development and is increasingly recognized for its importance in cancer. We demonstrated previously the overexpression of Notch-1 and its ligands in gliomas and showed that their knockdown inhibits glioma cell proliferation and survival. To elucidate the mechanisms downstream of Notch-1 in glioma cells, we performed microarray profiling of glioma cells transfected with Notch-1 small interfering RNA. Notable among downregulated transcripts was the epidermal growth factor receptor (EGFR), known to be overexpressed or amplified in gliomas and prominent in other cancers as well. Further studies confirmed that Notch-1 inhibition decreased EGFR messenger RNA (mRNA) and EGFR protein in glioma and other cell lines. Transfection with Notch-1 increased EGFR expression. Additionally, we found a significant correlation in levels of EGFR and Notch-1 mRNA in primary high-grade human gliomas. Subsequent experiments showed that p53, an activator of the EGFR promoter, is regulated by Notch-1. Experiments with p53-positive and -null cell lines confirmed that p53 partially mediates the effects of Notch-1 on EGFR expression. These results show for the first time that Notch-1 upregulates EGFR expression and also demonstrate Notch-1 regulation of p53 in gliomas. These observations have significant implications for understanding the mechanisms of Notch in cancer and development.


Assuntos
Receptores ErbB/genética , Regulação da Expressão Gênica , Glioma/genética , Receptor Notch1/fisiologia , Transcrição Gênica , Proteína Supressora de Tumor p53/genética , Biópsia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Genes Reporter , Genes p53 , Glioma/patologia , Humanos , Luciferases/genética , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Receptor Notch1/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
8.
Clin Cancer Res ; 22(5): 1103-10, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26446944

RESUMO

PURPOSE: The T790M gatekeeper mutation in the EGFR is acquired by some EGFR-mutant non-small cell lung cancers (NSCLC) as they become resistant to selective tyrosine kinase inhibitors (TKI). As third-generation EGFR TKIs that overcome T790M-associated resistance become available, noninvasive approaches to T790M detection will become critical to guide management. EXPERIMENTAL DESIGN: As part of a multi-institutional Stand-Up-To-Cancer collaboration, we performed an exploratory analysis of 40 patients with EGFR-mutant tumors progressing on EGFR TKI therapy. We compared the T790M genotype from tumor biopsies with analysis of simultaneously collected circulating tumor cells (CTC) and circulating tumor DNA (ctDNA). RESULTS: T790M genotypes were successfully obtained in 30 (75%) tumor biopsies, 28 (70%) CTC samples, and 32 (80%) ctDNA samples. The resistance-associated mutation was detected in 47% to 50% of patients using each of the genotyping assays, with concordance among them ranging from 57% to 74%. Although CTC- and ctDNA-based genotyping were each unsuccessful in 20% to 30% of cases, the two assays together enabled genotyping in all patients with an available blood sample, and they identified the T790M mutation in 14 (35%) patients in whom the concurrent biopsy was negative or indeterminate. CONCLUSIONS: Discordant genotypes between tumor biopsy and blood-based analyses may result from technological differences, as well as sampling different tumor cell populations. The use of complementary approaches may provide the most complete assessment of each patient's cancer, which should be validated in predicting response to T790M-targeted inhibitors.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Inibidores de Proteínas Quinases/administração & dosagem , Adulto , Afatinib , Idoso , Idoso de 80 Anos ou mais , Biópsia , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/sangue , Cloridrato de Erlotinib/administração & dosagem , Feminino , Gefitinibe , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Células Neoplásicas Circulantes/efeitos dos fármacos , Quinazolinas/administração & dosagem
9.
Sci Transl Med ; 7(302): 302fs35, 2015 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-26311727

RESUMO

Serial monitoring of circulating tumor DNA predicts recurrence after treatment for localized breast cancer (Garcia-Murillas et al., this issue).


Assuntos
Neoplasias da Mama/genética , DNA de Neoplasias/genética , Mutação , Feminino , Humanos
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