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1.
Lancet Oncol ; 24(12): e472-e518, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37924819

RESUMEN

The first Lancet Oncology Commission on Global Cancer Surgery was published in 2015 and serves as a landmark paper in the field of cancer surgery. The Commission highlighted the burden of cancer and the importance of cancer surgery, while documenting the many inadequacies in the ability to deliver safe, timely, and affordable cancer surgical care. This Commission builds on the first Commission by focusing on solutions and actions to improve access to cancer surgery globally, developed by drawing upon the expertise from cancer surgery leaders across the world. We present solution frameworks in nine domains that can improve access to cancer surgery. These nine domains were refined to identify solutions specific to the six WHO regions. On the basis of these solutions, we developed eight actions to propel essential improvements in the global capacity for cancer surgery. Our initiatives are broad in scope, pragmatic, affordable, and contextually applicable, and aimed at cancer surgeons as well as leaders, administrators, elected officials, and health policy advocates. We envision that the solutions and actions contained within the Commission will address inequities and promote safe, timely, and affordable cancer surgery for every patient, regardless of their socioeconomic status or geographic location.


Asunto(s)
Neoplasias , Cirujanos , Humanos , Neoplasias/cirugía , Salud Global , Política de Salud
2.
J Surg Oncol ; 128(6): 989-1002, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37818913

RESUMEN

BACKGROUND: Pancreatic cancer (PC) is a lethal malignancy with a significantly rising rate of incidence and mortality. This study aims to describe the influence of geography, socioeconomic development (based on the Human Development Index [HDI]), gender, and demographic shift on the temporal trends in the global burden of PC. METHODS: Data (2020-2040) relating to the incidence, mortality of PC, and demographic shifts based on continents and HDI areas were extracted from GLOBOCAN 2020. RESULTS: PC was associated with a higher socioeconomic status. Asia contributed to the majority of the burden, led by China. Advanced age (≥65 years) contributed to the majority of the burden in all socioeconomic regions except in Medium HDI and Low HDI countries, where the younger population (<65 years) contributed more. Females contributed to a higher burden in certain countries. Future trends for 2040 showed a >60% increase in the incidence and mortality of PC with an associated demographic shift. CONCLUSION: The global burden of PC is expected to rise significantly over the next few decades regardless of geography, socioeconomic development, age, and gender. Advance knowledge of this data can help to formulate strategies and public health policies to specifically target countries and populations at risk.


Asunto(s)
Salud Global , Neoplasias Pancreáticas , Femenino , Humanos , Anciano , Incidencia , Bases de Datos Factuales , Clase Social , Neoplasias Pancreáticas/epidemiología , Neoplasias Pancreáticas
3.
J Surg Oncol ; 128(6): 980-988, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37818916

RESUMEN

BACKGROUND: Gallbladder cancer (GBC) is a rare but lethal malignancy with a dismal prognosis. The aim of this study is to analyze the burdens and trends of GBC across the world based on geography, socioeconomic development (based on human development index [HDI]), and gender. METHODS: GLOBOCAN 2020 database was used to extract data (2020-2040) relating to the incidence and mortality of GBC across the world. RESULTS: Asia had the highest burden of GBC with India and China contributing to majority of the absolute burden. The burden of GBC by age standardized rate was highest in Latin America (Bolivia and Chile) and Southeast Asia (Bangladesh and Nepal). Medium HDI countries had a higher mortality rate compared to very high HDI countries. Females had a higher predilection for GBC across different regions and socioeconomic groups. GBC burden is expected to significantly increase across the world by 2040 with variable trends across different regions, age groups, and genders. CONCLUSION: The global burden of GBC will significantly increase over the next two decades with marked regional and demographic variations. The results of this study will empower national and global health leaders to develop policies to address the increasing burden of this lethal malignancy.


Asunto(s)
Carcinoma in Situ , Neoplasias de la Vesícula Biliar , Humanos , Masculino , Femenino , Neoplasias de la Vesícula Biliar/epidemiología , Salud Global , India/epidemiología , Pronóstico , Incidencia
4.
Materials (Basel) ; 14(19)2021 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-34639964

RESUMEN

Nanograined nuclear materials are expected to have a better performance as spallation targets and nuclear fuels than conventional materials, but many basic properties of these materials are still unknown. The present work aims to contribute to their better understanding by studying the effect of grain size on the melting and solid-solid transitions of nanograined UC2-y. We laser-heated 4 nm-10 nm grain size samples with UC2-y as the main phase (but containing graphite and UO2 as impurities) under inert gas to temperatures above 3000 K, and their behavior was studied by thermal radiance spectroscopy. The UC2-y solidification point (2713(30) K) and α-UC2 to ß-UC2 solid-solid transition temperature (2038(10) K) were observed to remain unchanged when compared to bulk crystalline materials with micrometer grain sizes. After melting, the composite grain size persisted at the nanoscale, from around 10 nm to 20 nm, pointing to an effective role of carbon in preventing the rapid diffusion of uranium and grain growth.

6.
Nanomaterials (Basel) ; 10(12)2020 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-33316919

RESUMEN

This paper presents an experimental study about the preparation, by electrospinning, of uranium carbide fibers with nanometric grain size. Viscous solutions of cellulose acetate and uranyl salts (acetate, acetylacetonate, and formate) on acetic acid and 2,4-pentanedione, adjusted to three different polymer concentrations, 10, 12.5, and 15 weight %, were used for electrospinning. Good quality precursor fibers were obtained from solutions with a 15% cellulose acetate concentration, the best ones being produced from the uranyl acetate solution. As-spun precursor fibers were then decomposed by slow heating until 823 K under argon, resulting in a mixture of nano-grained UO2 and C fibers. A last carboreduction was then carried out under vacuum at 2073 K for 2 h. The final material displayed UC2-y as the major phase, with grain sizes in the 4 nm-10 nm range. UO2+x was still present in moderate concentrations (~30 vol.%). This is due to uncomplete carboreduction that can be explained by the fiber morphology, limiting the effective contact between C and UO2 grains.

8.
J Surg Oncol ; 121(3): 547-560, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31867736

RESUMEN

BACKGROUND: Na+ /H+ exchanger regulatory factor 1 (NHERF1) has been implicated in the tumorigenesis of several cancer types and is a potential therapeutic target. The current study evaluated the relationship between NHERF1 expression and clinical outcome in colorectal cancer (CRC). METHODS: NHERF1 expression was evaluated by immunohistochemistry in 167 patients with CRC primary tumors, 37 patients with no disease, and 27 patients with metastatic CRC (mCRC); and in the orthotopically implanted tumors in mice. NHERF1 expression was manipulated in CRC cells using inducible short hairpin RNAs to determine its biological functions. RESULTS: High expression of NHERF1 correlated with CRC progression and metastasis, as well as significantly worse overall survival, recurrence-free survival, and disease-specific survival. Orthotopic implantation studies demonstrated increased NHERF1 expression in liver metastases. Treatment of CRC xenografts with insulin-like growth factor 1 receptor (IGF1R) inhibitors downregulated NHERF1 expression, indicating NHERF1 is downstream of IGF1R signaling. Knockdown of NHERF1 increased apoptosis and reduced X-linked inhibitor of apoptosis protein (XIAP) and survivin expression, indicating NHERF1 is critical for CRC cell survival. CONCLUSION: NHERF1 expression levels correlated with worse prognosis in patients with CRC and plays a critical role in CRC cell survival. Together, our findings establish NHERF1 as a novel potential marker for increased risk of CRC-specific mortality and identify NHERF1 as an attractive therapeutic target for mCRC treatment.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Fosfoproteínas/biosíntesis , Intercambiadores de Sodio-Hidrógeno/biosíntesis , Anciano , Animales , Biomarcadores de Tumor/biosíntesis , Línea Celular Tumoral , Neoplasias Colorrectales/patología , Células HCT116 , Xenoinjertos , Humanos , Masculino , Ratones , Ratones Desnudos , Persona de Mediana Edad , Tasa de Supervivencia
9.
PLoS One ; 13(7): e0200657, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30024920

RESUMEN

Mutations in the gene Adenomatous Polyposis Coli or APC appear in most sporadic cases of colorectal cancer and it is the most frequent mutation causing hereditary Familial Adenomatous Polyposis. The detailed molecular mechanism by which APC mutations predispose to the development of colorectal cancer is not completely understood. This is in part due to the lack of accessibility to appropriate models that recapitulate the early events associated with APC mediated intestinal transformation. We have established a novel platform utilizing human induced Pluripotent Stem cells or iPSC from normal or FAP-specific APC mutant individuals and evaluated the effect of the mutation in the cells before and after differentiation into intestinal organoids. In order to minimize genetic background effects, we also established an isogenic platform using TALEN-mediated gene editing. Comparison of normal and APC mutant iPSC revealed a significant defect in cell identity and polarity due to the presence of APC in heterozygosity as well as chromosomal aberrations including abnormal anaphases and centrosome numbers. Importantly, upon specification into intestinal progeny, APC heterozygosity was responsible for a major change in the transcriptional identity of the cells with dysregulation of key signaling pathways, including metabolic reprogramming, abnormal lipid metabolism and intestinal-specific cadherin expression. In conclusion, we have developed a novel iPSC/intestinal model of APC mutagenesis and provide strong evidence that APC in heterozygosity imparts a clear phenotypic and molecular defect, affecting basic cellular functions and integrity, providing novel insights in the earlier events of APC-mediated tumorigenesis.


Asunto(s)
Proteína de la Poliposis Adenomatosa del Colon/genética , Poliposis Adenomatosa del Colon/genética , Células Madre Pluripotentes Inducidas/metabolismo , Mutagénesis , Mutación , Poliposis Adenomatosa del Colon/patología , Diferenciación Celular/genética , Transformación Celular Neoplásica/genética , Células Cultivadas , Regulación del Desarrollo de la Expresión Génica , Células HEK293 , Humanos , Células Madre Pluripotentes Inducidas/citología , Intestinos/patología , Organoides/metabolismo , Transducción de Señal/genética
10.
Oncotarget ; 9(4): 5216-5232, 2018 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-29435174

RESUMEN

Colorectal cancer (CRC) remains one of the leading causes of cancer related deaths in the United States. Currently, there are limited therapeutic options for patients suffering from CRC, none of which focus on the cell signaling mechanisms controlled by the popular kinase family, cyclin dependent kinases (CDKs). Here we evaluate a Pfizer developed compound, CP668863, that inhibits cyclin-dependent kinase 5 (CDK5) in neurodegenerative disorders. CDK5 has been implicated in a number of cancers, most recently as an oncogene in colorectal cancers. Our lab synthesized and characterized CP668863 - now called 20-223. In our established colorectal cancer xenograft model, 20-223 reduced tumor growth and tumor weight indicating its value as a potential anti-CRC agent. We subjected 20-223 to a series of cell-free and cell-based studies to understand the mechanism of its anti-tumor effects. In our hands, in vitro 20-223 is most potent against CDK2 and CDK5. The clinically used CDK inhibitor AT7519 and 20-223 share the aminopyrazole core and we used it to benchmark the 20-223 potency. In CDK5 and CDK2 kinase assays, 20-223 was ∼3.5-fold and ∼65.3-fold more potent than known clinically used CDK inhibitor, AT7519, respectively. Cell-based studies examining phosphorylation of downstream substrates revealed 20-223 inhibits the kinase activity of CDK5 and CDK2 in multiple CRC cell lines. Consistent with CDK5 inhibition, 20-223 inhibited migration of CRC cells in a wound-healing assay. Profiling a panel of CRC cell lines for growth inhibitory effects showed that 20-223 has nanomolar potency across multiple CRC cell lines and was on an average >2-fold more potent than AT7519. Cell cycle analyses in CRC cells revealed that 20-223 phenocopied the effects associated with AT7519. Collectively, these findings suggest that 20-223 exerts anti-tumor effects against CRC by targeting CDK 2/5 and inducing cell cycle arrest. Our studies also indicate that 20-223 is a suitable lead compound for colorectal cancer therapy.

11.
Neoplasia ; 20(3): 289-294, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29471289

RESUMEN

The biological underpinnings for racial disparities in colorectal cancer (CRC) incidence remain to be elucidated. We have previously reported that the cohesin SA-1 down-regulation is an early event in colon carcinogenesis which is dramatically accentuated in African-Americans. In order to investigate the mechanism, we evaluated single nucleotide polymorphisms (SNPs) for association with SA-1-related outcomes followed by gene editing of candidate SNP. We observed that rs34149860 SNP was significantly associated with a lower colonic mucosal SA-1 expression and evaluation of public databases showed striking racial discordance. Given that the predicted SNP would alter miR-29b binding site, we used CRISPR knock-in in CRC cells and demonstrated that the SNP but not wild-type had profound alterations in SA-1 expression with miR-29b inhibitor. This is the first demonstration of high-order chromatin regulators as a modulator of racial differences, risk alteration with SNPs and finally specific modulation by microRNAs.


Asunto(s)
Proteínas de Ciclo Celular/genética , Proteínas Cromosómicas no Histona/genética , Neoplasias Colorrectales/genética , Regulación hacia Abajo/genética , Proteínas Nucleares/genética , Polimorfismo de Nucleótido Simple/genética , Sitios de Unión/genética , Carcinogénesis/genética , Línea Celular Tumoral , Predisposición Genética a la Enfermedad/genética , Células HCT116 , Humanos , MicroARNs/genética , Cohesinas
14.
PLoS One ; 12(4): e0176096, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28414818

RESUMEN

In this study, we have uncovered a novel crosstalk between TGFß and IGF-1R signaling pathways. We show for the first time that expression and activation of IRS-1, an IGF-1R adaptor protein, is decreased by TGFß/Smad3 signaling. Loss or attenuation of TGFß activation leads to elevated expression and phosphorylation of IRS-1 in colon cancer cells, resulting in enhanced cell proliferation, decreased apoptosis and increased tumor growth in vitro and in vivo. Downregulation of IRS-1 expression reversed Smad3 knockdown-mediated oncogenic phenotypes, indicating that TGFß/Smad3 signaling inhibits cell proliferation and increases apoptosis at least partially through the inhibition of IRS-1 expression and activation. Additionally, the TGFß/Smad3/IRS-1 signaling axis regulates expression of cyclin D1 and XIAP, which may contribute to TGFß/Smad3/IRS-1-mediated cell cycle progression and survival. Given that loss of TGFß signaling occurs frequently in colon cancer, an important implication of our study is that IRS-1 could be a potential therapeutic target for colon cancer treatment.


Asunto(s)
Apoptosis/genética , Proliferación Celular/genética , Neoplasias del Colon/genética , Neoplasias del Colon/metabolismo , Proteínas Sustrato del Receptor de Insulina/antagonistas & inhibidores , Proteína smad3/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Línea Celular Tumoral , Colon/metabolismo , Colon/patología , Neoplasias del Colon/patología , Ciclina D1/metabolismo , Regulación hacia Abajo/genética , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Fosforilación/genética , Transducción de Señal/genética , Proteína Inhibidora de la Apoptosis Ligada a X/metabolismo
15.
Oncotarget ; 8(13): 20543-20557, 2017 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-28423551

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is the second leading cause of cancer-related mortality in the United States. There is an increasing need for the identification of biomarkers of pre-malignant and early stage CRC to improve risk-stratification and screening recommendations. In this study, we investigated the possibility of metabolic and mitochondrial reprogramming early in the pre-malignant colorectal field. METHODS: Rectal biopsies were taken from 81 patients undergoing screening colonoscopy, and gene expression of metabolic and mitochondrial markers were assessed using real time quantitative PCR. Validation studies were performed in two different animal models of colon carcinogenesis: Pirc rats and AOM-treated rats. RESULTS: We found evidence of a Warburg effect in the normal-appearing rectal mucosa of patients harboring precancerous lesions elsewhere in the colon compared to control patients, with a significant increase in HIF1α, SLC2A1 (referred to as GLUT1), PKM2, and LDHA. We also found evidence of early mitochondrial changes in the colorectal field of patients harboring pre-cancerous lesions, with significantly increased mitochondrial gene expression of DRP1 (fission), OPA1 (fusion), PGC1-α (biogenesis), UCP2 (uncoupling) and mtND1 (copy number). Similar results were observed in the two different animal models. CONCLUSIONS: These results demonstrate for the first time evidence of early Warburg-like metabolic changes as well as changes in mitochondrial function, dynamics and mtDNA copy number in endoscopically normal premalignant colorectal mucosal field. These findings provide an opportunity for the development of metabolic biomarkers that could be used for improving screening recommendations and risk-stratification. This also provides a potential target for novel chemopreventive strategies in the pre-malignant colorectal field.


Asunto(s)
Transformación Celular Neoplásica/metabolismo , Neoplasias Colorrectales/metabolismo , Lesiones Precancerosas/metabolismo , Animales , Transformación Celular Neoplásica/patología , Neoplasias Colorrectales/patología , Humanos , Inmunohistoquímica , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Lesiones Precancerosas/patología , Ratas , Reacción en Cadena en Tiempo Real de la Polimerasa , Transcriptoma
16.
J Surg Oncol ; 115(5): 591-602, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28345140

RESUMEN

BACKGROUND: The aim of this study is to describe the influence of geography, socio-economic development, and demographic shift on the trends in global incidence, mortality, and prevalence of liver cancer (LC). METHODS: Data (2012-2030) relating to LC and demographic shifts based on WHO regions and HDI areas were extracted from GLOBOCAN 2012 and analyzed to evaluate trends in incidence, mortality, and prevalence. RESULTS: The results of our study document a rising global burden of LC with the maximum impact in the WPRO region. We did not observe a definite association between LC and higher socio-economic status with the highest burden in the MHD region. For the MHD region, we noticed age reversal in burden from the younger age group currently to the older age group in the future (2030). Another finding is the high burden and early onset of disease in some low-income countries such as Mongolia, Lao PDR, and Vietnam. CONCLUSION: The results of our study demonstrate a rising global burden of LC with some significant but uneven trends based on geography, age, and socio-economic status. This information can be used to shape policy and aid strategic targeting of resources to areas with the highest burden.


Asunto(s)
Salud Global , Neoplasias Hepáticas/epidemiología , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Bases de Datos Factuales , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Dinámica Poblacional , Prevalencia , Distribución por Sexo , Clase Social , Adulto Joven
17.
J Surg Oncol ; 115(5): 580-590, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28138977

RESUMEN

BACKGROUND: The aim of this study is to describe the trends and variations in the global burden of gallbladder cancer (GBC) with an emphasis on geographic variations and female gender. METHODS: Data (2012-2030) relating to GBC was extracted from GLOBOCAN 2012 database and analyzed. RESULTS: The results of our study document a rising global burden of GBC with geographic and gender variations. The highest burden was noted in the WPRO region (based on WHO regions), Asia (based on continents) and India, Chile, and China (based on countries). The less developed regions of the world account for the majority of the global burden of GBC. The geographic variations are also present within individual countries such as in India and Chile. Females are afflicted at a much higher rate with GBC and this predilection is exaggerated in countries with higher incidence such as India and Chile. In females, people of certain ethnic groups and lower socio-economic standing are at a higher risk. CONCLUSIONS: Our study demonstrates a rising global burden of GBC with some specific data on geographic and gender-based variations which can be used to develop strategies at the global as well as the high-risk individual country level.


Asunto(s)
Neoplasias de la Vesícula Biliar/epidemiología , Salud Global , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Bases de Datos Factuales , Femenino , Accesibilidad a los Servicios de Salud/economía , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Prevalencia , Distribución por Sexo , Clase Social , Adulto Joven
18.
J Surg Oncol ; 115(5): 619-630, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28194798

RESUMEN

BACKGROUND: The aim of this study is to describe the trends and variations in the global burden of colorectal cancer (CRC). METHODS: Data (2012-2030) relating to CRC was extracted from GLOBOCAN 2012 database and analyzed. RESULTS: The results of our study demonstrate a rising global burden of colorectal cancer which persists until the year 2035 and likely beyond. The rise in the global burden is not uniform with significant variations influenced by geographic location, socio-economic status, age, and gender. Although the EURO region has the highest burden, Asia as a continent continues to bear the heaviest brunt of the disease. Although the burden of disease is higher in more developed regions, mortality is considerably higher in less developed regions and this gap widens over the next two decades. The disease predominantly affects the male gender across all regions of the world. Age has a complex relation with the burden of CRC and is affected by the cross-influences relating to socio-economic status. CONCLUSIONS: The results of our study demonstrate a rising global burden of CRC with some unique variations. Knowledge of this data can increase awareness and help strategic targeting of efforts and resources.


Asunto(s)
Neoplasias Colorrectales/epidemiología , Salud Global , Distribución por Edad , Anciano , Anciano de 80 o más Años , Bases de Datos Factuales , Femenino , Humanos , Incidencia , Masculino , Distribución por Sexo
19.
Curr Opin Gastroenterol ; 33(1): 47-52, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27798442

RESUMEN

PURPOSE OF REVIEW: Despite the large investment of resources from screening, the fact that colorectal cancer remains the second leading cause of cancer deaths among Americans underscores the need for alternative strategies. Thus, a major clinical and research imperative is personalize clinical care, while focusing on risk stratification for screening, surveillance, chemoprevention, and therapeutic intervention. RECENT FINDINGS: A complicating factor that colorectal cancer is biologically heterogeneous for at least four consensus molecular subtypes presents clear challenges for developing robust molecular biomarkers. SUMMARY: The purpose of the review is to discuss the genetics and molecular biology of colonic neoplasia, high and low penetrance, and racial disparities in colonic neoplasia. Finally, we put forth the emerging concept of greater genomic landscape and the idea of chromatin protection therapy as a novel adjuvant to chemotherapy.


Asunto(s)
Neoplasias del Colon/genética , Neoplasias Colorrectales/genética , Disparidades en el Estado de Salud , Neoplasias del Colon/fisiopatología , Predisposición Genética a la Enfermedad , Humanos , Penetrancia
20.
Gastroenterology ; 151(6): 1232-1244.e10, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27523981

RESUMEN

BACKGROUND & AIMS: Little is known about the origin of pancreatic intraductal papillary mucinous neoplasms (IPMN). Pancreatic duct glands (PDGs) are gland-like outpouches budding off the main pancreatic ducts that function as a progenitor niche for the ductal epithelium; they express gastric mucins and have characteristics of side-branch IPMNs. We investigated whether PDGs are a precursor compartment for IPMNs and the role of Trefoil factor family 2 (TFF2)-a protein expressed by PDGs and the gastric mucosa that are involved in epithelial repair and tumor suppression. METHODS: We obtained pancreatectomy specimens from 20 patients with chronic pancreatitis, 13 with low-grade side-branch IPMNs, and 15 patients with PDAC; histologically normal pancreata were used as controls (n = 18). Samples were analyzed by immunohistochemistry to detect TFF1 and TFF2 and cell proliferation. We performed mitochondrial DNA mutational mapping studies to determine the cell lineage and fate of PDG cells. Pdx1-Cre;LSL-KRASG12D (KC) mice were bred with TFF2-knockout mice to generate KC/Tff2-/- and KC/Tff2+/- mice. Pancreata were collected and histologically analyzed for formation of IPMN, pancreatic intraepithelial neoplasias, and PDAC, in addition to proliferation and protein expression. Human pancreatic ductal epithelial cells and PDAC cell lines were transfected with vectors to overexpress or knock down TFF2 or SMAD4. RESULTS: Histologic analysis of human samples revealed gastric-type IPMN to comprise 2 molecularly distinct layers: a basal crypt segment that expressed TFF2 and overlying papillary projections. Proliferation occurred predominantly in the PDG-containing basal segments. Mitochondrial mutation mapping revealed a 97% match between the profiles of proliferating PDG cells and their overlying nonproliferative IPMN cells. In contrast to KC mice, 2-month-old KC/Tff2+/- and KC/Tff2-/- mice developed prominent papillary structures in the duct epithelium with cystic metaplasia of the PDG, which resembled human IPMN; these expressed gastric mucins (MUC5AC and MUC6), but not the intestinal mucin MUC2. KC/TFF2-knockout mice developed a greater number and higher grade of pancreatic intraepithelial neoplasias than KC mice, and 1 mouse developed an invasive adenocarcinoma. Expression of TFF2 reduced proliferation of PDAC cells 3-fold; this effect required up-regulation and activation of SMAD4. We found expression of TFF2 to be down-regulated in human PDAC by hypermethylation of its promoter. CONCLUSIONS: In histologic analyses of human IPMNs, we found PDGs to form the basal segment and possibly serve as a progenitor compartment. TFF2 has tumor-suppressor activity in the mouse pancreas and prevents formation of mucinous neoplasms.


Asunto(s)
Epitelio/patología , Neoplasias Quísticas, Mucinosas y Serosas/patología , Conductos Pancreáticos/patología , Neoplasias Pancreáticas/patología , Factor Trefoil-2/genética , Factor Trefoil-2/metabolismo , Animales , Carcinoma Ductal Pancreático , Línea Celular Tumoral , Proliferación Celular/genética , Metilación de ADN , Análisis Mutacional de ADN , ADN Mitocondrial/análisis , Regulación hacia Abajo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Antígeno Ki-67/análisis , Masculino , Metaplasia/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mucina 5AC/análisis , Mucina 6/análisis , Mutación , Neoplasias Quísticas, Mucinosas y Serosas/química , Neoplasias Quísticas, Mucinosas y Serosas/genética , Páncreas , Conductos Pancreáticos/química , Neoplasias Pancreáticas/química , Neoplasias Pancreáticas/genética , Pancreatitis Crónica , Regiones Promotoras Genéticas/genética , Proteína Smad4/genética , Proteína Smad4/metabolismo , Factor Trefoil-1/análisis , Factor Trefoil-2/análisis
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