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3.
Artigo em Inglês | MEDLINE | ID: mdl-34341011

RESUMO

Carriers of a pathogenic/likely pathogenic (P/LP) BRCA1/BRCA2/ATM/PALB2 variant are at increased risk of pancreatic ductal adenocarcinoma (PDAC), yet current guidelines recommend surveillance only for those with a family history of PDAC. We aimed to investigate outcomes of endoscopic ultrasound (EUS)-based PDAC surveillance in BRCA1/BRCA2/ATM/PALB2 carriers without a family history of PDAC. We performed a retrospective analysis of all P/LP BRCA1/BRCA2/ATM/PALB2 carriers who underwent EUS at a tertiary care center. Of 194 P/LP BRCA1/BRCA2/ATM/PALB2 carriers who underwent EUS, 64 (33%) had no family history of PDAC and had at least 1 EUS for PDAC surveillance. These individuals underwent 143 total EUSs, were predominantly female (72%), and BRCA2 carriers (73%), with the majority having a personal history of cancer other than PDAC (67%). The median age at time of first EUS was 62 years [interquartile range (IQR), 53-67 years] and a median of 2 EUSs (IQR 1-3) were performed per patient, with a median of 3 years (IQR 2-4.5 years) between the first and last EUS for those with more than 1 EUS. Pancreatic abnormalities were detected in 44%, including cysts in 27%, and incidental luminal abnormalities in 41%. Eight percent developed a new pancreatic mass or cyst during surveillance, 2 individuals developed PDAC, and no serious complications resulted from surveillance. After discussion of the risks, limitations, and potential benefits, PDAC surveillance can be considered in BRCA1/BRCA2/ATM/PALB2 carriers without a family history of PDAC; however, the effectiveness of PDAC surveillance in this population requires further study. PREVENTION RELEVANCE: BRCA1/BRCA2/ATM/PALB2 carriers have increased pancreatic ductal adenocarcinoma (PDAC) risk, yet are typically not eligible for PDAC surveillance in the absence of PDAC family history. Herein we describe outcomes of PDAC surveillance in BRCA1/BRCA2/ATM/PALB2 carriers without a family history of PDAC, showing that PDAC surveillance can be considered in this high-risk group.

6.
EMBO Rep ; 22(9): e51872, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34324787

RESUMO

Epithelial plasticity, or epithelial-to-mesenchymal transition (EMT), is a well-recognized form of cellular plasticity, which endows tumor cells with invasive properties and alters their sensitivity to various agents, thus representing a major challenge to cancer therapy. It is increasingly accepted that carcinoma cells exist along a continuum of hybrid epithelial-mesenchymal (E-M) states and that cells exhibiting such partial EMT (P-EMT) states have greater metastatic competence than those characterized by either extreme (E or M). We described recently a P-EMT program operating in vivo by which carcinoma cells lose their epithelial state through post-translational programs. Here, we investigate the underlying mechanisms and report that prolonged calcium signaling induces a P-EMT characterized by the internalization of membrane-associated E-cadherin (ECAD) and other epithelial proteins as well as an increase in cellular migration and invasion. Signaling through Gαq-associated G-protein-coupled receptors (GPCRs) recapitulates these effects, which operate through the downstream activation of calmodulin-Camk2b signaling. These results implicate calcium signaling as a trigger for the acquisition of hybrid/partial epithelial-mesenchymal states in carcinoma cells.

7.
Trends Cancer ; 7(8): 731-750, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34074623

RESUMO

ATP hydrolysis and downstream signaling pathways in the extracellular space have a major impact upon tumor progression and metastasis. The complexity and interdependence of various cell types in the extracellular space have been increasingly appreciated in recent years. With increased awareness of the importance of this signaling pathway in the pathogenic development and progression of malignancies, there has been attention to therapeutic strategies targeting extracellular adenosine metabolism and signaling. This review summarizes the molecular and physiologic roles of extracellular ATP and adenosine in normal and disease states, and potential therapeutic applications.

8.
Cell Stem Cell ; 28(8): 1343-1361, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34129814

RESUMO

The esophagus and stomach, joined by a unique transitional zone, contain actively dividing epithelial stem cells required for organ homeostasis. Upon prolonged inflammation, epithelial cells in both organs can undergo a cell fate switch leading to intestinal metaplasia, predisposing to malignancy. Here we discuss the biology of gastroesophageal stem cells and their role as cells of origin in cancer. We summarize the interactions between the stromal niche and gastroesophageal stem cells in metaplasia and early expansion of mutated stem-cell-derived clones during carcinogenesis. Finally, we review new approaches under development to better study gastroesophageal stem cells and advance the field.


Assuntos
Esôfago de Barrett , Neoplasias , Humanos , Metaplasia , Células-Tronco
9.
Pancreas ; 50(6): 807-814, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34149034

RESUMO

OBJECTIVES: Data from the International Cancer of the Pancreas Screening Consortium studies have demonstrated that screening for pancreatic ductal adenocarcinoma can be effective and that surveillance improves survival in high-risk individuals. Endoscopic ultrasound (EUS) and cross-sectional imaging are both used, although there is some suggestion that EUS is superior. Demonstration of the cost-effectiveness of screening is important to implement screening in high-risk groups. METHODS: Results from centers with EUS-predominant screening were pooled to evaluate efficacy of index EUS in screening. A decision analysis model simulated the outcome of high-risk patients who undergo screening and evaluated the parameters that would make screening cost-effective at a US $100,000 per quality-adjusted life-year willingness to pay. RESULTS: One-time index EUS has a sensitivity of 71.25% and specificity of 99.82% to detection to detect high-risk lesions. Screening with index EUS was cost-effective, particularly at lifetime pancreatic cancer probabilities of greater than 10.8%, or at lower probabilities if life expectancy after resection of a lesion that was at least 16 years, and if missed, lesion rates on index EUS are 5% or less. CONCLUSIONS: Pancreatic cancer screening can be cost-effective through index EUS, particularly for those individuals at high-lifetime risk of cancer.

10.
Cell Stem Cell ; 28(6): 987-988, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34087158

RESUMO

In this issue of Cell Stem Cell, Huang et al. (2021) and Breunig et al. (2021) developed human stem-cell-derived organoid culture systems to recapitulate pancreatic acinar and ductal lineages. This provides opportunities to study cellular plasticity and transformation in pancreatic cancer initiation and progression.


Assuntos
Pâncreas Exócrino , Neoplasias Pancreáticas , Células-Tronco Pluripotentes , Células Acinares , Humanos , Organoides , Pâncreas , Ductos Pancreáticos
11.
Nat Genet ; 53(6): 881-894, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33972779

RESUMO

Esophageal squamous cell carcinomas (ESCCs) harbor recurrent chromosome 3q amplifications that target the transcription factor SOX2. Beyond its role as an oncogene in ESCC, SOX2 acts in development of the squamous esophagus and maintenance of adult esophageal precursor cells. To compare Sox2 activity in normal and malignant tissue, we developed engineered murine esophageal organoids spanning normal esophagus to Sox2-induced squamous cell carcinoma and mapped Sox2 binding and the epigenetic and transcriptional landscape with evolution from normal to cancer. While oncogenic Sox2 largely maintains actions observed in normal tissue, Sox2 overexpression with p53 and p16 inactivation promotes chromatin remodeling and evolution of the Sox2 cistrome. With Klf5, oncogenic Sox2 acquires new binding sites and enhances activity of oncogenes such as Stat3. Moreover, oncogenic Sox2 activates endogenous retroviruses, inducing expression of double-stranded RNA and dependence on the RNA editing enzyme ADAR1. These data reveal SOX2 functions in ESCC, defining targetable vulnerabilities.


Assuntos
Adenosina Desaminase/metabolismo , Epigenoma , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Regiões 3' não Traduzidas/genética , Animais , Sequência de Bases , Carcinogênese/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Retrovirus Endógenos/genética , Elementos Facilitadores Genéticos/genética , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Humanos , Interferons/metabolismo , Íntrons/genética , Fatores de Transcrição Kruppel-Like/genética , Camundongos , Organoides/patologia , Ligação Proteica , RNA de Cadeia Dupla/metabolismo , Fatores de Transcrição SOXB1/genética , Proteína Supressora de Tumor p53/metabolismo
12.
Gastroenterology ; 161(2): 453-462.e15, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33839100

RESUMO

BACKGROUND AND AIMS: Lynch syndrome is associated with pathogenic variants in 4 mismatch repair (MMR) genes that increase lifetime risk of colorectal cancer. Guidelines recommend intensive colorectal cancer surveillance with colonoscopy every 1-2 years starting at age 25 years for all carriers of Lynch syndrome-associated variants, regardless of gene product. We constructed a simulation model to analyze the effects of different ages of colonoscopy initiation and surveillance intervals for each MMR gene (MLH1, MSH2, MSH6, and PMS2) on colorectal cancer incidence and mortality, quality-adjusted life-years, and cost. METHODS: Using published literature, we developed a Markov simulation model of Lynch syndrome progression for patients with each MMR variant. The model simulated clinical trials of Lynch syndrome carriers, varying age of colonoscopy initiation (5-year increments from 25-40 years), and surveillance intervals (1-5 years). We assessed the optimal strategy for each gene, defined as the strategy with the highest quality-adjusted life-years and incremental cost-effectiveness ratio below a $100,000 willingness-to-pay threshold. RESULTS: Optimal surveillance for patients with pathogenic variants in the MLH1 and MSH2 genes was colonoscopy starting at age 25 years, with 1- to 2-year surveillance intervals. Initiating colonoscopy at age 35 and 40 years, with 3-year intervals, was cost-effective for patients with pathogenic variants in MSH6 or PMS2, respectively. CONCLUSIONS: We developed a simulation model to select optimal surveillance starting ages and intervals for patients with Lynch syndrome based on MMR variant. The model supports recommendations for intensive surveillance of patients with Lynch syndrome-associated variants in MLH1 or MSH2. However, for patients with Lynch syndrome-associated variants of MSH6 or PMS2, later initiation of surveillance at 35 and 40 years, respectively, and at 3-year intervals, can be considered.

13.
Pancreatology ; 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33926820

RESUMO

BACKGROUND: COVID-19 pandemic-related disruptions to EUS-based pancreatic cancer surveillance in high-risk individuals remain uncertain. METHODS: Analysis of enrolled participants in the CAPS5 Study, a prospective multicenter study of pancreatic cancer surveillance in high-risk individuals. RESULTS: Amongst 693 enrolled high-risk individuals under active surveillance, 108 (16%) had an EUS scheduled during the COVID-19 pandemic-related shutdown (median length of 78 days) in the spring of 2020, with 97% of these procedures being canceled. Of these canceled surveillance EUSs, 83% were rescheduled in a median of 4.1 months, however 17% were not rescheduled after 6 months follow-up. Prior history of cancer was associated with increased likelihood of rescheduling. To date no pancreatic cancer has been diagnosed among those whose surveillance was delayed. CONCLUSIONS: COVID-19 delayed pancreatic cancer surveillance with no adverse outcomes in efficiently rescheduled individuals. However, 1 in 6 high-risk individuals had not rescheduled surveillance, indicating the need for vigilance to ensure timely surveillance rescheduling.

14.
Pancreas ; 50(3): 251-279, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33835956

RESUMO

ABSTRACT: Despite considerable research efforts, pancreatic cancer is associated with a dire prognosis and a 5-year survival rate of only 10%. Early symptoms of the disease are mostly nonspecific. The premise of improved survival through early detection is that more individuals will benefit from potentially curative treatment. Artificial intelligence (AI) methodology has emerged as a successful tool for risk stratification and identification in general health care. In response to the maturity of AI, Kenner Family Research Fund conducted the 2020 AI and Early Detection of Pancreatic Cancer Virtual Summit (www.pdac-virtualsummit.org) in conjunction with the American Pancreatic Association, with a focus on the potential of AI to advance early detection efforts in this disease. This comprehensive presummit article was prepared based on information provided by each of the interdisciplinary participants on one of the 5 following topics: Progress, Problems, and Prospects for Early Detection; AI and Machine Learning; AI and Pancreatic Cancer-Current Efforts; Collaborative Opportunities; and Moving Forward-Reflections from Government, Industry, and Advocacy. The outcome from the robust Summit conversations, to be presented in a future white paper, indicate that significant progress must be the result of strategic collaboration among investigators and institutions from multidisciplinary backgrounds, supported by committed funders.

15.
JCI Insight ; 6(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33755595

RESUMO

Most colorectal cancers (CRCs) are moderately differentiated or well differentiated, a status that is preserved even in metastatic tumors. However, the molecular mechanisms underlying CRC differentiation remain to be elucidated. Herein, we unravel a potentially novel posttranscriptional regulatory mechanism via a LIN28B/CDX2 signaling axis that plays a critical role in mediating CRC differentiation. Owing to a large number of mRNA targets, the mRNA-binding protein LIN28B has diverse functions in development, metabolism, tissue regeneration, and tumorigenesis. Our RNA-binding protein IP (RIP) assay revealed that LIN28B directly binds CDX2 mRNA, which is a pivotal homeobox transcription factor in normal intestinal epithelial cell identity and differentiation. Furthermore, LIN28B overexpression resulted in enhanced CDX2 expression to promote differentiation in subcutaneous xenograft tumors generated from CRC cells and metastatic tumor colonization through mesenchymal-epithelial transition in CRC liver metastasis mouse models. A ChIP sequence for CDX2 identified α-methylacyl-CoA racemase (AMACR) as a potentially novel transcriptional target of CDX2 in the context of LIN28B overexpression. We also found that AMACR enhanced intestinal alkaline phosphatase activity, which is known as a key component of intestinal differentiation, through the upregulation of butyric acid. Overall, we demonstrated that LIN28B promotes CRC differentiation through the CDX2/AMACR axis.

16.
Genes Dev ; 35(7-8): 528-541, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33737385

RESUMO

Esophageal squamous cell carcinoma (ESCC) is one of the most lethal cancers worldwide and evolves often to lung metastasis. P53R175H (homologous to Trp53 R172H in mice) is a common hot spot mutation. How metastasis is regulated by p53R175H in ESCC remains to be investigated. To investigate p53R175H-mediated molecular mechanisms, we used a carcinogen-induced approach in Trp53R172H/- mice to model ESCC. In the primary Trp53R172H/- tumor cell lines, we depleted Trp53R172H (shTrp53) and observed a marked reduction in cell invasion in vitro and lung metastasis burden in a tail-vein injection model in comparing isogenic cells (shCtrl). Furthermore, we performed bulk RNA-seq to compare gene expression profiles of metastatic and primary shCtrl and shTrp53 cells. We identified the YAP-BIRC5 axis as a potential mediator of Trp53 R172H -mediated metastasis. We demonstrate that expression of Survivin, an antiapoptotic protein encoded by BIRC5, increases in the presence of Trp53R172H Furthermore, depletion of Survivin specifically decreases Trp53R172H-driven lung metastasis. Mechanistically, Trp53R172H but not wild-type Trp53, binds with YAP in ESCC cells, suggesting their cooperation to induce Survivin expression. Furthermore, Survivin high expression level is associated with increased metastasis in several GI cancers. Taken together, this study unravels new insights into how mutant p53 mediates metastasis.


Assuntos
Neoplasias Pulmonares/fisiopatologia , Survivina/genética , Survivina/metabolismo , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Pulmonares/genética , Camundongos , Mutação , Metástase Neoplásica , Transcriptoma , Proteína Supressora de Tumor p53/metabolismo
17.
Cancer Discov ; 11(7): 1774-1791, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33589425

RESUMO

Pancreatic cancer metastasis is a leading cause of cancer-related deaths, yet very little is understood regarding the underlying biology. As a result, targeted therapies to inhibit metastasis are lacking. Here, we report that the parathyroid hormone-related protein (PTHrP encoded by PTHLH) is frequently amplified as part of the KRAS amplicon in patients with pancreatic cancer. PTHrP upregulation drives the growth of both primary and metastatic tumors in mice and is highly enriched in pancreatic ductal adenocarcinoma metastases. Loss of PTHrP-either genetically or pharmacologically-dramatically reduces tumor burden, eliminates metastasis, and enhances overall survival. These effects are mediated in part through a reduction in epithelial-to-mesenchymal transition, which reduces the ability of tumor cells to initiate metastatic cascade. Spp1, which encodes osteopontin, is revealed to be a downstream effector of PTHrP. Our results establish a new paradigm in pancreatic cancer whereby PTHrP is a driver of disease progression and emerges as a novel therapeutic vulnerability. SIGNIFICANCE: Pancreatic cancer often presents with metastases, yet no strategies exist to pharmacologically inhibit this process. Herein, we establish the oncogenic and prometastatic roles of PTHLH, a novel amplified gene in pancreatic ductal adenocarcinoma. We demonstrate that blocking PTHrP activity reduces primary tumor growth, prevents metastasis, and prolongs survival in mice.This article is highlighted in the In This Issue feature, p. 1601.

18.
Artigo em Inglês | MEDLINE | ID: mdl-33470698

RESUMO

BACKGROUND: Early detection of pancreatic ductal adenocarcinoma (PDA) may improve survival. We previously developed a clinical prediction model among patients with new-onset diabetes to help identify PDAs 6 months prior to the clinical diagnosis of the cancer. We developed and internally validated a new model to predict PDA risk among those newly diagnosed with impaired fasting glucose (IFG). METHODS: We conducted a retrospective cohort study in The Health Improvement Network (THIN) (1995-2013) from the UK. Eligible study patients had newly diagnosed IFG during follow-up in THIN. The outcome was incident PDA diagnosed within 3 years of IFG diagnosis. Candidate predictors were factors associated with PDA, glucose metabolism or both. RESULTS: Among the 138 232 eligible patients with initial IFG diagnosis, 245 (0.2%) were diagnosed with PDA within 3 years. The median time from IFG diagnosis to clinical PDA diagnosis was 326 days (IQR 120-588). The final prediction model included age, BMI, proton pump inhibitor use, total cholesterol, low-density lipoprotein, alanine aminotransferase and alkaline phosphatase. The model achieved good discrimination [area under the curve 0.71 (95% CI, 0.67-0.75)] and calibration (Hosmer and Lemeshow goodness-of-fit test P > 0.05 in 17 of the 20 imputed data sets) with optimism of 0.0012662 (95% CI, -0.00932 to 0.0108771). CONCLUSIONS: We developed and internally validated a sequential PDA prediction model based on clinical information routinely available at the initial appearance of IFG. If externally validated, this model could significantly extend our ability to detect PDAs at an earlier stage.

19.
EMBO Rep ; 22(2): e48351, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33403789

RESUMO

Esophageal squamous cell carcinoma (ESCC) is the most common subtype of esophageal cancer worldwide. The most commonly mutated gene in ESCC is TP53. Using a combinatorial genetic and carcinogenic approach, we generate a novel mouse model of ESCC expressing either mutant or null p53 and show that mutant p53 exhibits enhanced tumorigenic properties and displays a distinct genomic profile. Through RNA-seq analysis, we identify several endocytic recycling genes, including Rab Coupling Protein (Rab11-FIP1), which are significantly downregulated in mutant p53 tumor cells. In 3-dimensional (3D) organoid models, genetic knockdown of Rab11-FIP1 results in increased organoid size. Loss of Rab11-FIP1 increases tumor cell invasion in part through mutant p53 but also in an independent manner. Furthermore, loss of Rab11-FIP1 in human ESCC cell lines decreases E-cadherin expression and increases mesenchymal lineage-specific markers, suggesting induction of epithelial-mesenchymal transition (EMT). Rab11-FIP1 regulates EMT through direct inhibition of Zeb1, a key EMT transcriptional factor. Our novel findings reveal that Rab11-FIP1 regulates organoid formation, tumor cell invasion, and EMT.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Transição Epitelial-Mesenquimal/genética , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica
20.
Gastroenterology ; 160(1): 346-361.e24, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33007300

RESUMO

BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDAC) is characterized by a fibroblast-rich desmoplastic stroma. Cancer-associated fibroblasts (CAFs) have been shown to display a high degree of interconvertible states including quiescent, inflammatory, and myofibroblastic phenotypes; however, the mechanisms by which this plasticity is achieved are poorly understood. Here, we aim to elucidate the role of CAF plasticity and its impact on PDAC biology. METHODS: To investigate the role of mesenchymal plasticity in PDAC progression, we generated a PDAC mouse model in which CAF plasticity is modulated by genetic depletion of the transcription factor Prrx1. Primary pancreatic fibroblasts from this mouse model were further characterized by functional in vitro assays. To characterize the impact of CAFs on tumor differentiation and response to chemotherapy, various coculture experiments were performed. In vivo, tumors were characterized by morphology, extracellular matrix composition, and tumor dissemination and metastasis. RESULTS: Our in vivo findings showed that Prrx1-deficient CAFs remain constitutively activated. Importantly, this CAF phenotype determines tumor differentiation and disrupts systemic tumor dissemination. Mechanistically, coculture experiments of tumor organoids and CAFs showed that CAFs shape the epithelial-to-mesenchymal phenotype and confer gemcitabine resistance of PDAC cells induced by CAF-derived hepatocyte growth factor. Furthermore, gene expression analysis showed that patients with pancreatic cancer with high stromal expression of Prrx1 display the squamous, most aggressive, subtype of PDAC. CONCLUSIONS: Here, we define that the Prrx1 transcription factor is critical for tuning CAF activation, allowing a dynamic switch between a dormant and an activated state. This work shows that Prrx1-mediated CAF plasticity has significant impact on PDAC biology and therapeutic resistance.


Assuntos
Fibroblastos Associados a Câncer/fisiologia , Carcinoma Ductal Pancreático/etiologia , Carcinoma Ductal Pancreático/patologia , Proteínas de Homeodomínio/fisiologia , Neoplasias Pancreáticas/etiologia , Neoplasias Pancreáticas/patologia , Animais , Plasticidade Celular/fisiologia , Modelos Animais de Doenças , Camundongos
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