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1.
Br J Cancer ; 130(1): 125-134, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37950093

RESUMEN

INTRODUCTION: Pancreatic cancer is a highly aggressive cancer, and early diagnosis significantly improves patient prognosis due to the early implementation of curative-intent surgery. Our study aimed to implement machine-learning algorithms to aid in early pancreatic cancer diagnosis based on minimally invasive liquid biopsies. MATERIALS AND METHODS: The analysis data were derived from nine public pancreatic cancer miRNA datasets and two sequencing datasets from 26 pancreatic cancer patients treated in our medical center, featuring small RNAseq data for patient-matched tumor and non-tumor samples and serum. Upon batch-effect removal, systematic analyses for differences between paired tissue and serum samples were performed. The robust rank aggregation (RRA) algorithm was used to reveal feature markers that were co-expressed by both sample types. The repeatability and real-world significance of the enriched markers were then determined by validating their expression in our patients' serum. The top candidate markers were used to assess the accuracy of predicting pancreatic cancer through four machine learning methods. Notably, these markers were also applied for the identification of pancreatic cancer and pancreatitis. Finally, we explored the clinical prognostic value, candidate targets and predict possible regulatory cell biology mechanisms involved. RESULTS: Our multicenter analysis identified hsa-miR-1246, hsa-miR-205-5p, and hsa-miR-191-5p as promising candidate serum biomarkers to identify pancreatic cancer. In the test dataset, the accuracy values of the prediction model applied via four methods were 94.4%, 84.9%, 82.3%, and 83.3%, respectively. In the real-world study, the accuracy values of this miRNA signatures were 82.3%, 83.5%, 79.0%, and 82.2. Moreover, elevated levels of these miRNAs were significant indicators of advanced disease stage and allowed the discrimination of pancreatitis from pancreatic cancer with an accuracy rate of 91.5%. Elevated expression of hsa-miR-205-5p, a previously undescribed blood marker for pancreatic cancer, is associated with negative clinical outcomes in patients. CONCLUSION: A panel of three miRNAs was developed with satisfactory statistical and computational performance in real-world data. Circulating hsa-miRNA 205-5p serum levels serve as a minimally invasive, early detection tool for pancreatic cancer diagnosis and disease staging and might help monitor therapy success.


Asunto(s)
MicroARNs , Neoplasias Pancreáticas , Pancreatitis , Humanos , Detección Precoz del Cáncer , MicroARNs/metabolismo , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Biopsia Líquida
2.
Cell Mol Life Sci ; 77(9): 1811-1825, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31363815

RESUMEN

Premature intrapancreatic trypsinogen activation is widely regarded as an initiating event for acute pancreatitis. Previous studies have alternatively implicated secretory vesicles, endosomes, lysosomes, or autophagosomes/autophagolysosomes as the primary site of trypsinogen activation, from which a cell-damaging proteolytic cascade originates. To identify the subcellular compartment of initial trypsinogen activation we performed a time-resolution analysis of the first 12 h of caerulein-induced pancreatitis in transgenic light chain 3 (LC3)-GFP autophagy reporter mice. Intrapancreatic trypsin activity increased within 60 min and serum amylase within 2 h, but fluorescent autophagosome formation only by 4 h of pancreatitis in parallel with a shift from cytosolic LC3-I to membranous LC3-II on Western blots. At 60 min, activated trypsin in heavier subcellular fractions was co-distributed with cathepsin B, but not with the autophagy markers LC3 or autophagy protein 16 (ATG16). Supramaximal caerulein stimulation of primary pancreatic acini derived from LC3-GFP mice revealed that trypsinogen activation is independent of autophagolysosome formation already during the first 15 min of exposure to caerulein. Co-localization studies (with GFP-LC3 autophagosomes versus Ile-Pro-Arg-AMC trypsin activity and immunogold-labelling of lysosomal-associated membrane protein 2 [LAMP-2] versus trypsinogen activation peptide [TAP]) indicated active trypsin in autophagolysosomes only at the later timepoints. In conclusion, during the initiating phase of caerulein-induced pancreatitis, premature protease activation develops independently of autophagolysosome formation and in vesicles arising from the secretory pathway. However, autophagy is likely to regulate overall intracellular trypsin activity during the later stages of this disease.


Asunto(s)
Autofagia , Ceruletida/toxicidad , Pancreatitis/patología , Tripsina/metabolismo , Tripsinógeno/metabolismo , Animales , Autofagosomas/metabolismo , Endosomas/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Pancreatitis/inducido químicamente , Pancreatitis/metabolismo , Vesículas Secretoras/metabolismo
3.
Gastroenterology ; 156(1): 203-217.e20, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30296435

RESUMEN

BACKGROUND AND AIMS: Cells in pancreatic ductal adenocarcinoma (PDAC) undergo autophagy, but its effects vary with tumor stage and genetic factors. We investigated the consequences of varying levels of the autophagy related 5 (Atg5) protein on pancreatic tumor formation and progression. METHODS: We generated mice that express oncogenic Kras in primary pancreatic cancer cells and have homozygous disruption of Atg5 (A5;Kras) or heterozygous disruption of Atg5 (A5+/-;Kras), and compared them with mice with only oncogenic Kras (controls). Pancreata were analyzed by histology and immunohistochemistry. Primary tumor cells were isolated and used to perform transcriptome, metabolome, intracellular calcium, extracellular cathepsin activity, and cell migration and invasion analyses. The cells were injected into wild-type littermates, and orthotopic tumor growth and metastasis were monitored. Atg5 was knocked down in pancreatic cancer cell lines using small hairpin RNAs; cell migration and invasion were measured, and cells were injected into wild-type littermates. PDAC samples were obtained from independent cohorts of patients and protein levels were measured on immunoblot and immunohistochemistry; we tested the correlation of protein levels with metastasis and patient survival times. RESULTS: A5+/-;Kras mice, with reduced Atg5 levels, developed more tumors and metastases, than control mice, whereas A5;Kras mice did not develop any tumors. Cultured A5+/-;Kras primary tumor cells were resistant to induction and inhibition of autophagy, had altered mitochondrial morphology, compromised mitochondrial function, changes in intracellular Ca2+ oscillations, and increased activity of extracellular cathepsin L and D. The tumors that formed in A5+/-;Kras mice contained greater numbers of type 2 macrophages than control mice, and primary A5+/-;Kras tumor cells had up-regulated expression of cytokines that regulate macrophage chemoattraction and differentiation into M2 macrophage. Knockdown of Atg5 in pancreatic cancer cell lines increased their migratory and invasive capabilities, and formation of metastases following injection into mice. In human PDAC samples, lower levels of ATG5 associated with tumor metastasis and shorter survival time. CONCLUSIONS: In mice that express oncogenic Kras in pancreatic cells, heterozygous disruption of Atg5 and reduced protein levels promotes tumor development, whereas homozygous disruption of Atg5 blocks tumorigenesis. Therapeutic strategies to alter autophagy in PDAC should consider the effects of ATG5 levels to avoid the expansion of resistant and highly aggressive cells.


Asunto(s)
Proteína 5 Relacionada con la Autofagia/metabolismo , Autofagia , Carcinoma Ductal Pancreático/metabolismo , Movimiento Celular , Neoplasias Pancreáticas/metabolismo , Animales , Proteína 5 Relacionada con la Autofagia/deficiencia , Proteína 5 Relacionada con la Autofagia/genética , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/prevención & control , Carcinoma Ductal Pancreático/secundario , Catepsinas/genética , Catepsinas/metabolismo , Proliferación Celular , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Genes ras , Heterocigoto , Homocigoto , Ratones Noqueados , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/prevención & control , Transducción de Señal , Carga Tumoral , Células Tumorales Cultivadas
4.
Int J Mol Sci ; 21(6)2020 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-32210079

RESUMEN

(1) Background: IL-17A accelerates pancreatic intraepithelial neoplasia (PanIN) progression. In this study, we examined whether IL-17A/IL-17RA promotes pancreatic ductal adenocarcinoma (PDAC) aggressiveness in terms of survival and cancer stem cell modulation. (2) Methods: In vitro, the wound-healing assay, the sphere formation assay, and flow cytometry were applied to assess cancer stem cell features. In vivo, pancreatic tumors were induced in C57BL/6 mice using electroporation with oncogenic plasmids (P53-/- R172H; KrasG12V). Anti-IL-17 antibodies were administered as immunotherapy. We analyzed IL-17A/IL-17RA related survival using publicly available transcriptomic data (n = 903). (3) Results: IL-17A/IL-17RA expression was not related to survival in PDAC patients. IL-17A neither induces stem cell markers nor increases sphere formation and cell motility in vitro. Blocking the IL-17A/IL-17RA axis in a murine pancreatic cancer model did not improve the survival of mice, but reduced the tumor burden slightly. (4) Conclusions: IL-17A does not promote stem cell expansion in PDAC cell lines. Blocking IL-17A/IL-17RA signaling does not interfere with pancreatic cancer development and progression and may not be considered as a promising monotherapy for PDAC.


Asunto(s)
Interleucina-17/metabolismo , Células Madre Neoplásicas/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/mortalidad , Receptores de Interleucina-17/metabolismo , Transducción de Señal , Animales , Biomarcadores , Carcinoma Ductal Pancreático/etiología , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/mortalidad , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Humanos , Interleucina-17/genética , Ratones , Terapia Molecular Dirigida , Neoplasias Pancreáticas/etiología , Neoplasias Pancreáticas/patología , Pronóstico , Receptores de Interleucina-17/genética , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Semin Cancer Biol ; 53: 139-155, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30081228

RESUMEN

A small subpopulation of cells within the bulk of tumors share features with somatic stem cells, in that, they are capable of self-renewal, they differentiate, and are highly resistant to conventional therapy. These cells have been referred to as cancer stem cells (CSCs). Recent reports support the central importance of a cancer stem cell-like niche that appears to help foster the generation and maintenance of CSCs. In response to signals provided by this microenvironment, CSCs express the tumorigenic characteristics that can drive tumor metastasis by the induction of epithelial-mesenchymal-transition (EMT) that in turn fosters the migration and recolonization of the cells as secondary tumors within metastatic niches. We summarize here recent advances in cancer stem cell research including the characterization of their genetic and epigenetic features, metabolic specialities, and crosstalk with aging-associated processes. Potential strategies for targeting CSCs, and their niche, by regulating CSCs plasticity, or therapeutic sensitivity is discussed. Finally, it is hoped that new strategies and related therapeutic approaches as outlined here may help prevent the formation of the metastatic niche, as well as counter tumor progression and metastatic growth.


Asunto(s)
Neoplasias/genética , Células Madre Neoplásicas/metabolismo , Nicho de Células Madre/genética , Microambiente Tumoral/genética , Anilidas/uso terapéutico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Proteínas Hedgehog/antagonistas & inhibidores , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Células Madre Neoplásicas/efectos de los fármacos , Piridinas/uso terapéutico , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Nicho de Células Madre/efectos de los fármacos , Microambiente Tumoral/efectos de los fármacos
6.
J Biol Chem ; 291(28): 14717-31, 2016 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-27226576

RESUMEN

Pancreatitis is associated with premature activation of digestive proteases in the pancreas. The lysosomal hydrolase cathepsin B (CTSB) is a known activator of trypsinogen, and its deletion reduces disease severity in experimental pancreatitis. Here we studied the activation mechanism and subcellular compartment in which CTSB regulates protease activation and cellular injury. Cholecystokinin (CCK) increased the activity of CTSB, cathepsin L, trypsin, chymotrypsin, and caspase 3 in vivo and in vitro and induced redistribution of CTSB to a secretory vesicle-enriched fraction. Neither CTSB protein nor activity redistributed to the cytosol, where the CTSB inhibitors cystatin-B/C were abundantly present. Deletion of CTSB reduced and deletion of cathepsin L increased intracellular trypsin activation. CTSB deletion also abolished CCK-induced caspase 3 activation, apoptosis-inducing factor, as well as X-linked inhibitor of apoptosis protein degradation, but these depended on trypsinogen activation via CTSB. Raising the vesicular pH, but not trypsin inhibition, reduced CTSB activity. Trypsin inhibition did not affect apoptosis in hepatocytes. Deletion of CTSB affected apoptotic but not necrotic acinar cell death. In summary, CTSB in pancreatitis undergoes activation in a secretory, vesicular, and acidic compartment where it activates trypsinogen. Its deletion or inhibition regulates acinar cell apoptosis but not necrosis in two models of pancreatitis. Caspase 3-mediated apoptosis depends on intravesicular trypsinogen activation induced by CTSB, not CTSB activity directly, and this mechanism is pancreas-specific.


Asunto(s)
Apoptosis , Catepsina B/metabolismo , Páncreas/enzimología , Pancreatitis/patología , Péptido Hidrolasas/metabolismo , Animales , Catepsina B/antagonistas & inhibidores , Activación Enzimática , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Pancreatitis/enzimología , Fracciones Subcelulares/enzimología
7.
Am J Physiol Gastrointest Liver Physiol ; 311(3): G548-60, 2016 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-27514475

RESUMEN

Pancreatitis is an inflammatory disease of the pancreas characterized by dysregulated activity of digestive enzymes, necrosis, immune infiltration, and pain. Repeated incidence of pancreatitis is an important risk factor for pancreatic cancer. Legumain, a lysosomal cysteine protease, has been linked to inflammatory diseases such as atherosclerosis, stroke, and cancer. Until now, legumain activation has not been studied during pancreatitis. We used a fluorescently quenched activity-based probe to assess legumain activation during caerulein-induced pancreatitis in mice. We detected activated legumain by ex vivo imaging, confocal microscopy, and gel electrophoresis. Compared with healthy controls, legumain activity in the pancreas of caerulein-treated mice was increased in a time-dependent manner. Legumain was localized to CD68(+) macrophages and was not active in pancreatic acinar cells. Using a small-molecule inhibitor of legumain, we found that this protease is not essential for the initiation of pancreatitis. However, it may serve as a biomarker of disease, since patients with chronic pancreatitis show strongly increased legumain expression in macrophages. Moreover, the occurrence of legumain-expressing macrophages in regions of acinar-to-ductal metaplasia suggests that this protease may influence reprogramming events that lead to inflammation-induced pancreatic cancer.


Asunto(s)
Cisteína Endopeptidasas/metabolismo , Macrófagos/enzimología , Pancreatitis/enzimología , Animales , Ceruletida/toxicidad , Cisteína Endopeptidasas/genética , Inhibidores Enzimáticos/farmacología , Femenino , Regulación Enzimológica de la Expresión Génica , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Pancreatitis/inducido químicamente
8.
Gastroenterology ; 149(3): 765-76.e10, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26001927

RESUMEN

BACKGROUND & AIMS: Little is known about the pathogenic mechanisms of chronic pancreatitis. We investigated the roles of complement component 5 (C5) in pancreatic fibrogenesis in mice and patients. METHODS: Chronic pancreatitis was induced by ligation of the midpancreatic duct, followed by a single supramaximal intraperitoneal injection of cerulein, in C57Bl6 (control) and C5-deficient mice. Some mice were given injections of 2 different antagonists of the receptor for C5a over 21 days. In a separate model, mice were given injections of cerulein for 10 weeks to induce chronic pancreatitis. Direct effects of C5 were studied in cultured primary cells. We performed genotype analysis for the single-nucleotide polymorphisms rs 17611 and rs 2300929 in C5 in patients with pancreatitis and healthy individuals (controls). Blood cells from 976 subjects were analyzed by transcriptional profiling. RESULTS: During the initial phase of pancreatitis, levels of pancreatic damage were similar between C5-deficient and control mice. During later stages of pancreatitis, C5-deficient mice and mice given injections of C5a-receptor antagonists developed significantly less pancreatic fibrosis than control mice. Primary pancreatic stellate cells were activated in vitro by C5a. There were no differences in the rs 2300929 SNP between subjects with or without pancreatitis, but the minor allele rs17611 was associated with a significant increase in levels of C5 in whole blood. CONCLUSIONS: In mice, loss of C5 or injection of a C5a-receptor antagonist significantly reduced the level of fibrosis of chronic pancreatitis, but this was not a consequence of milder disease in early stages of pancreatitis. C5 might be a therapeutic target for chronic pancreatitis.


Asunto(s)
Complemento C5/metabolismo , Células Estrelladas Pancreáticas/metabolismo , Pancreatitis Crónica/metabolismo , Compuestos de Anilina/farmacología , Animales , Estudios de Casos y Controles , Ceruletida , Complemento C5/deficiencia , Complemento C5/genética , Modelos Animales de Enfermedad , Fibrosis , Predisposición Genética a la Enfermedad , Ligadura , Ratones Endogámicos C57BL , Ratones Noqueados , Conductos Pancreáticos/cirugía , Células Estrelladas Pancreáticas/efectos de los fármacos , Células Estrelladas Pancreáticas/inmunología , Células Estrelladas Pancreáticas/patología , Pancreatitis Crónica/inducido químicamente , Pancreatitis Crónica/tratamiento farmacológico , Pancreatitis Crónica/genética , Pancreatitis Crónica/inmunología , Pancreatitis Crónica/patología , Fenotipo , Polimorfismo de Nucleótido Simple , Receptor de Anafilatoxina C5a/antagonistas & inhibidores , Receptor de Anafilatoxina C5a/metabolismo , Tetrahidronaftalenos/farmacología , Factores de Tiempo
9.
Gastroenterology ; 148(3): 626-638.e17, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25497209

RESUMEN

BACKGROUND & AIMS: Little is known about the mechanisms of the progressive tissue destruction, inflammation, and fibrosis that occur during development of chronic pancreatitis. Autophagy is involved in multiple degenerative and inflammatory diseases, including pancreatitis, and requires the protein autophagy related 5 (ATG5). We created mice with defects in autophagy to determine its role in pancreatitis. METHODS: We created mice with pancreas-specific disruption of Atg5 (Ptf1aCreex1;Atg5F/F mice) and compared them to control mice. Pancreata were collected and histology, immunohistochemistry, transcriptome, and metabolome analyses were performed. ATG5-deficient mice were placed on diets containing 25% palm oil and compared with those on a standard diet. Another set of mice received the antioxidant N-acetylcysteine. Pancreatic tissues were collected from 8 patients with chronic pancreatitis (CP) and compared with pancreata from ATG5-deficient mice. RESULTS: Mice with pancreas-specific disruption of Atg5 developed atrophic CP, independent of ß-cell function; a greater proportion of male mice developed CP than female mice. Pancreata from ATG5-deficient mice had signs of inflammation, necrosis, acinar-to-ductal metaplasia, and acinar-cell hypertrophy; this led to tissue atrophy and degeneration. Based on transcriptome and metabolome analyses, ATG5-deficient mice produced higher levels of reactive oxygen species than control mice, and had insufficient activation of glutamate-dependent metabolism. Pancreata from these mice had reduced autophagy, increased levels of p62, and increases in endoplasmic reticulum stress and mitochondrial damage, compared with tissues from control mice; p62 signaling to Nqo1 and p53 was also activated. Dietary antioxidants, especially in combination with palm oil-derived fatty acids, blocked progression to CP and pancreatic acinar atrophy. Tissues from patients with CP had many histologic similarities to those from ATG5-deficient mice. CONCLUSIONS: Mice with pancreas-specific disruption of Atg5 develop a form of CP similar to that of humans. CP development appears to involve defects in autophagy, glutamate-dependent metabolism, and increased production of reactive oxygen species. These mice might be used to identify therapeutic targets for CP.


Asunto(s)
Autofagia/genética , Estrés del Retículo Endoplásmico/genética , Proteínas Asociadas a Microtúbulos/genética , Páncreas/metabolismo , Pancreatitis Crónica/genética , Acetilcisteína/farmacología , Animales , Atrofia , Autofagia/inmunología , Proteína 5 Relacionada con la Autofagia , Estrés del Retículo Endoplásmico/efectos de los fármacos , Estrés del Retículo Endoplásmico/inmunología , Femenino , Depuradores de Radicales Libres/farmacología , Humanos , Inflamación , Masculino , Ratones , Ratones Noqueados , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Aceite de Palma , Páncreas/efectos de los fármacos , Páncreas/inmunología , Pancreatitis Crónica/inmunología , Pancreatitis Crónica/patología , Aceites de Plantas/farmacología , Especies Reactivas de Oxígeno/inmunología , Especies Reactivas de Oxígeno/metabolismo , Factores Sexuales , Proteína p53 Supresora de Tumor/inmunología , Proteína p53 Supresora de Tumor/metabolismo
11.
Mol Cell Biochem ; 400(1-2): 253-63, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25416448

RESUMEN

Transient hepatic ischemia can cause significant liver injury. A central and early event in ischemia/reperfusion (I/R) injury is the impairment of mitochondria. The phospholipid cardiolipin (CL) is required for efficient mitochondrial function. The aim of this study was to analyze composition, content, and oxidation of CL in dependence of I/R stress. Therefore, we exposed rat livers to 20 min ischemia by interrupting the perfusion with Krebs-Ringer solution in situ. Tissue histology as well as increased activities of LDH, GLDH, and ASAT analysed in the efflux after 50 min reperfusion indicated impairment of the liver. For the analysis of local CL distribution the liver homogenate was separated according to density into 11 fractions. The fractions displayed different contents of CL and citrate synthase peaking at density of about 1.07 g/cm(3). Among the fractions, the distribution of molecular CL species significantly differed. I/R caused loss of about 30 % CL and 17 % citrate synthase activity. Further, I/R shifted the CL and citrate synthase activity profile toward lower densities. Oxidized CL was exclusively found in fractions with high CL and citrate synthase content after I/R stress. I/R treatment caused significant changes in the distribution of molecular CL species. Our data demonstrate that I/R causes significant decrease in CL content and increase of oxidized CL that may be of impact for impairment of mitochondrial function by I/R. These results lead to the suggestion that strategies supporting anti-oxidative defence and CL synthesis may be beneficial to reduce I/R injury of the liver.


Asunto(s)
Cardiolipinas/metabolismo , Citrato (si)-Sintasa/metabolismo , Isquemia/metabolismo , Hígado/metabolismo , Animales , Isquemia/patología , Lipogénesis , Hígado/patología , Mitocondrias/metabolismo , Mitocondrias/patología , Fosfolípidos/metabolismo , Ratas , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología
12.
Gut ; 63(3): 494-505, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23564336

RESUMEN

BACKGROUND: Autoimmune pancreatitis (AIP) in humans invariably responds to steroid treatment, but little is known about the underlying pathogenesis and the benefits of alternative treatments. OBJECTIVE: To study the pathogenesis, and the efficacy of alternative immunosuppressant agents in the MRL/Mp mouse model of AIP. DESIGN: MRL/Mp mice were pretreated for 4 weeks with polyinosinic:polycytidylic acid to induce AIP. Pancreatic sections of mice genetically deleted for CTLA-4 were analysed. Blockage of CTLA-4 was achieved by intraperitoneal antibody treatment with 2 µg/g anti-mouse-CD152. Subsequent therapeutic studies were performed for a period of 4 weeks using cyclosporine A (40 µg/g), rapamycin (1 µg/g) or azathioprine (15 µg/g). RESULTS: Blockage of CTLA-4 in MRL/Mp mice suppressed regulatory T cell (Treg) function and raised the effector T cell (Teff) response with subsequent histomorphological organ destruction, indicating that AIP is a T cell-driven disease. Using an established histopathological score, we found that dexamethasone, cyclosporine A and rapamycin, but less so azathioprine, reduced pancreatic damage. However, the beneficial effects of cyclosporine A and rapamycin were achieved via different mechanisms: cyclosporine A inhibited Teff activation and proliferation whereas rapamycin led to selective expansion of Tregs which subsequently suppressed the Teff response. CONCLUSIONS: The calcineurin inhibitor cyclosporine A and the mammalian target of rapamycin (mTOR) inhibitor, rapamycin, improve the course of AIP in MRL/Mp mice via different mechanisms. These findings further support the concept of autoreactive T cells as key players in the pathogenesis of AIP and suggest that cyclosporine A and rapamycin should be considered for treatment of AIP in humans.


Asunto(s)
Enfermedades Autoinmunes/tratamiento farmacológico , Ciclosporina/uso terapéutico , Inmunosupresores/uso terapéutico , Páncreas/inmunología , Pancreatitis Crónica/tratamiento farmacológico , Sirolimus/uso terapéutico , Subgrupos de Linfocitos T/metabolismo , Animales , Enfermedades Autoinmunes/inducido químicamente , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/patología , Azatioprina/uso terapéutico , Biomarcadores/metabolismo , Antígeno CTLA-4/antagonistas & inhibidores , Proliferación Celular/efectos de los fármacos , Ciclosporina/farmacología , Dexametasona/uso terapéutico , Esquema de Medicación , Femenino , Citometría de Flujo , Inmunosupresores/farmacología , Activación de Linfocitos/efectos de los fármacos , Ratones , Ratones Endogámicos , Páncreas/efectos de los fármacos , Páncreas/patología , Pancreatitis Crónica/inducido químicamente , Pancreatitis Crónica/inmunología , Pancreatitis Crónica/patología , Poli I-C , Distribución Aleatoria , Sirolimus/farmacología , Subgrupos de Linfocitos T/efectos de los fármacos , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/metabolismo , Resultado del Tratamiento
13.
J Biol Chem ; 288(33): 24049-62, 2013 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-23814066

RESUMEN

Chymotrypsin C (CTRC) is a proteolytic regulator of trypsinogen autoactivation in humans. CTRC cleavage of the trypsinogen activation peptide stimulates autoactivation, whereas cleavage of the calcium binding loop promotes trypsinogen degradation. Trypsinogen mutations that alter these regulatory cleavages lead to increased intrapancreatic trypsinogen activation and cause hereditary pancreatitis. The aim of this study was to characterize the regulation of autoactivation of mouse trypsinogens by mouse Ctrc. We found that the mouse pancreas expresses four trypsinogen isoforms to high levels, T7, T8, T9, and T20. Only the T7 activation peptide was cleaved by mouse Ctrc, causing negligible stimulation of autoactivation. Surprisingly, mouse Ctrc poorly cleaved the calcium binding loop in all mouse trypsinogens. In contrast, mouse Ctrc readily cleaved the Phe-150-Gly-151 peptide bond in the autolysis loop of T8 and T9 and inhibited autoactivation. Mouse chymotrypsin B also cleaved the same peptide bond but was 7-fold slower. T7 was less sensitive to chymotryptic regulation, which involved slow cleavage of the Leu-149-Ser-150 peptide bond in the autolysis loop. Modeling indicated steric proximity of the autolysis loop and the activation peptide in trypsinogen, suggesting the cleaved autolysis loop may directly interfere with activation. We conclude that autoactivation of mouse trypsinogens is under the control of mouse Ctrc with some notable differences from the human situation. Thus, cleavage of the trypsinogen activation peptide or the calcium binding loop by Ctrc is unimportant. Instead, inhibition of autoactivation via cleavage of the autolysis loop is the dominant mechanism that can mitigate intrapancreatic trypsinogen activation.


Asunto(s)
Quimotripsina/metabolismo , Tripsinógeno/química , Tripsinógeno/metabolismo , Secuencia de Aminoácidos , Animales , Cationes , Cromatografía por Intercambio Iónico , Electroforesis en Gel Bidimensional , Activación Enzimática , Genoma/genética , Humanos , Isoenzimas/metabolismo , Ratones , Modelos Moleculares , Datos de Secuencia Molecular , Proteínas Mutantes/metabolismo , Mutación/genética , Páncreas/enzimología , Péptidos/metabolismo , Procesamiento Proteico-Postraduccional , Estructura Secundaria de Proteína , Tripsinógeno/genética
14.
Gastroenterology ; 144(1): 192-201, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23041330

RESUMEN

BACKGROUND & AIMS: The transcription factor nuclear factor-κB (NF-κB) (a heterodimer of NF-κB1p50 and RelA) is activated rapidly in acute pancreatitis (AP). However, it is not clear whether NF-κB promotes or protects against AP. We used the NF-κB inhibitor protein, inhibitor of κB (IκB)α, to study the roles of NF-κB in the development of AP in mice. METHODS: IκBα or the combination of IκBα and RelA selectively were deleted from pancreas of mice using the Cre/locus of cross-over P strategy; cerulein or L-arginine were used to induce AP. We performed microarray analyses of the IκBα- and RelA-deficient pancreata. DNA from healthy individuals and patients with acute or chronic pancreatitis were analyzed for variants in coding regions of alpha-1-antichymotrypsin. RESULTS: Mice with pancreas-specific deletion of IκBα had constitutive activation of RelA and a gene expression profile consistent with NF-κB activation; development of AP in these mice was attenuated and trypsin activation was impaired. However, AP was fully induced in mice with pancreas-specific deletion of IκBα and RelA. By using genome-wide expression analysis, we identified a cluster of NF-κB-regulated genes that might protect against the development of AP. The serine protease inhibitor 2A (Spi2a) was highly up-regulated in IκBα-deficient mice. Lentiviral-mediated expression of Spi2A reduced the development of AP in C57BL/6 and RelA-deficient mice. However, we did not correlate any variants of alpha-1-antichymotrypsin, the human homologue of Spi2a, with acute or chronic pancreatitis. CONCLUSIONS: Pancreas-specific deletion of IκBα results in nuclear translocation of RelA and reduces AP induction and trypsin activation in mice after administration of cerulein or L-arginine. Constitutive activation of RelA up-regulates Spi2A, which protects mice against the development of AP.


Asunto(s)
Proteínas I-kappa B/genética , FN-kappa B/metabolismo , Pancreatitis/genética , Pancreatitis/metabolismo , Serpinas/genética , Factor de Transcripción ReIA/genética , alfa 1-Antiquimotripsina/genética , Células Acinares , Animales , Arginina , Ceruletida , Citosol/metabolismo , Modelos Animales de Enfermedad , Perfilación de la Expresión Génica , Vectores Genéticos , Genotipo , Proteínas I-kappa B/metabolismo , Lentivirus , Ratones , Ratones Endogámicos C57BL , Análisis por Micromatrices , Inhibidor NF-kappaB alfa , Proteínas Nucleares/metabolismo , Páncreas/enzimología , Pancreatitis/inducido químicamente , Pancreatitis/patología , Fosforilación , Serpinas/metabolismo , Transducción de Señal , Factor de Transcripción ReIA/metabolismo , Tripsina/metabolismo , Regulación hacia Arriba
15.
Gut ; 62(3): 430-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22490516

RESUMEN

BACKGROUND: Acute pancreatitis has long been considered a disorder of pancreatic self-digestion, in which intracellular activation of digestive proteases induces tissue injury. Chemokines, released from damaged pancreatic cells then attract inflammatory cells, whose systemic action ultimately determines the disease severity. In the present work the opposite mechanism is investigated; that is, whether and how inflammatory cells can activate intracellular proteases. DESIGN: Using mice either deficient for the CD18-α subunit of the membrane attack complex-1 (MAC-1) complex or tumour necrosis factor (TNF)α, as well as after depletion of leucocyte subpopulations, pancreatitis was induced by 7-hourly caerulein injections (50 µg/kg, intraperitoneally). Pancreatic acini were coincubated in vitro from wild-type and cathepsin-B-deficient animals with phorbol-12-myristate-13-acetate (PMA)-activated neutrophils and macrophages, caerulein or TNFα, and activities of trypsin, cathepsin-B and caspase-3 were measured, as well as necrosis using fluorogenic substrates. TNFα was inhibited with monospecific antibodies. RESULTS: Deletion of CD18 prevented transmigration of leucocytes into the pancreas during pancreatitis, greatly reduced disease severity and abolished digestive protease activation. Depletion of neutrophils and macrophages equally reduced premature trypsinogen activation and disease severity. In vitro activated neutrophils and macrophages directly induced premature protease activation and cell death in pancreatic acini and stimulation of acini with TNFα induced caspase-3 activation and necrosis via a cathepsin-B and calcium-dependent mechanism. Neutralising antibodies against TNFα and genetic deletion of TNFα prevented leucocyte-induced trypsin activity and necrosis in isolated acini. CONCLUSIONS: The soluble inflammatory cell mediator TNFα directly induces premature protease activation and necrosis in pancreatic acinar cells. This activation depends on calcium and cathepsin-B activity. The findings from the present work further suggest that targeting TNFα, for which pharmaceutical agents are readily available, could be an effective treatment strategy that directly addresses the cellular causes of pancreatitis.


Asunto(s)
Células Acinares/patología , Caspasa 3/metabolismo , Catepsina B/metabolismo , Pancreatitis Aguda Necrotizante/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Western Blotting , Antígenos CD18/inmunología , Movimiento Celular , Ceruletida/efectos adversos , Activación Enzimática , Leucocitos/fisiología , Ratones , Necrosis/patología , Pancreatitis Aguda Necrotizante/inducido químicamente , Pancreatitis Aguda Necrotizante/enzimología , Pancreatitis Aguda Necrotizante/patología , Péptido Hidrolasas/metabolismo , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
16.
Artículo en Inglés | MEDLINE | ID: mdl-38837745

RESUMEN

Background: Uncover the pivotal link between lymphocyte-specific protein tyrosine kinase (Lck)-related genes and clinical risk stratification in pancreatic cancer. Methods: This study identifies shared genes between differentially expressed genes (DEGs) and Lck-related genes in pancreatic cancer using a methodological framework rooted in The Cancer Genome Atlas database. Feature gene selection is accomplished and a signature model is constructed. Statistical significant clinical endpoints such as overall survival (OS), disease-specific survival (DSS), and progression-free interval (PFI) were defined. Results: After performing random survival forest, Lasso regression, and multivariate Cox regression model, 7 trait genes out of 272 Lck-associated DEGs are selected to create a signature model that is independent of other clinical factors and can predict OS and DSS. It appears that high-risk patients have activated the TP53 signaling pathway and the cell cycle signaling pathway. LAMA3 turned out to be the hub gene of the signature with high expression in pancreatic cancer. Patients with increased expression of LAMA3 had a short OS, DSS, and PFI in comparison. The candidate competing endogenous RNA network of LAMA3 turned out to be OPI5-AS1/hsa-miR-186-5p/LAMA3 axis. Conclusions: A characteristic signature of seven Lck-related genes, especially LAMA3, has been shown to be a key factor in clinical risk stratification for pancreatic cancer.

17.
Sci Rep ; 13(1): 16362, 2023 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-37773315

RESUMEN

Current treatment for glioblastoma includes tumor resection followed by radiation, chemotherapy, and periodic post-operative examinations. Despite combination therapies, patients face a poor prognosis and eventual recurrence, which often occurs at the resection site. With standard MRI imaging surveillance, histologic changes may be overlooked or misinterpreted, leading to erroneous conclusions about the course of adjuvant therapy and subsequent interventions. To address these challenges, we propose an implantable system for accurate continuous recurrence monitoring that employs optical sensing of fluorescently labeled cancer cells and is implanted in the resection cavity during the final stage of tumor resection. We demonstrate the feasibility of the sensing principle using miniaturized system components, optical tissue phantoms, and porcine brain tissue in a series of experimental trials. Subsequently, the system electronics are extended to include circuitry for wireless energy transfer and power management and verified through electromagnetic field, circuit simulations and test of an evaluation board. Finally, a holistic conceptual system design is presented and visualized. This novel approach to monitor glioblastoma patients is intended to early detect recurrent cancerous tissue and enable personalization and optimization of therapy thus potentially improving overall prognosis.


Asunto(s)
Glioblastoma , Humanos , Animales , Porcinos , Glioblastoma/diagnóstico por imagen , Glioblastoma/terapia , Glioblastoma/patología , Recurrencia Local de Neoplasia/patología , Prótesis e Implantes , Pronóstico , Terapia Combinada
18.
Oncol Res ; 32(1): 227-239, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38188686

RESUMEN

Transient receptor potential (TRP) channels are strongly associated with colon cancer development and progression. This study leveraged a multivariate Cox regression model on publicly available datasets to construct a TRP channels-associated gene signature, with further validation of signature in real world samples from our hospital treated patient samples. Kaplan-Meier (K-M) survival analysis and receiver operating characteristic (ROC) curves were employed to evaluate this gene signature's predictive accuracy and robustness in both training and testing cohorts, respectively. Additionally, the study utilized the CIBERSORT algorithm and single-sample gene set enrichment analysis to explore the signature's immune infiltration landscape and underlying functional implications. The support vector machine algorithm was applied to evaluate the signature's potential in predicting chemotherapy outcomes. The findings unveiled a novel three TRP channels-related gene signature (MCOLN1, TRPM5, and TRPV4) in colon adenocarcinoma (COAD). The ROC and K-M survival curves in the training dataset (AUC = 0.761; p = 1.58e-05) and testing dataset (AUC = 0.699; p = 0.004) showed the signature's robust predictive capability for the overall survival of COAD patients. Analysis of the immune infiltration landscape associated with the signature revealed higher immune infiltration, especially an increased presence of M2 macrophages, in high-risk group patients compared to their low-risk counterparts. High-risk score patients also exhibited potential responsiveness to immune checkpoint inhibitor therapy, evident through increased CD86 and PD-1 expression profiles. Moreover, the TRPM5 gene within the signature was highly expressed in the chemoresistance group (p = 0.00095) and associated with poor prognosis (p = 0.036) in COAD patients, highlighting its role as a hub gene of chemoresistance. Ultimately, this signature emerged as an independent prognosis factor for COAD patients (p = 6.48e-06) and expression of model gene are validated by public data and real-world patients. Overall, this bioinformatics study provides valuable insights into the prognostic implications and potential chemotherapy resistance mechanisms associated with TRPs-related genes in colon cancer.


Asunto(s)
Adenocarcinoma , Neoplasias del Colon , Canales de Potencial de Receptor Transitorio , Humanos , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/genética , Resistencia a Antineoplásicos/genética , Biología Computacional
19.
Transl Oncol ; 38: 101783, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37716258

RESUMEN

The proportion of patients diagnosed with cancer has been shown to rise with the increasing aging global population. Advanced age is a major risk factor for morbidity and mortality in older adults. As individuals experience varying health statuses, particularly with age, it poses a challenge for medical professionals in the cancer field to obtain standardized treatment outcomes. Hence, relying solely on chronological age and disease-related parameters is inadequate for clinical decision-making for elderly patients. With functional, multimorbidity-related, and psychosocial changes that occur with aging, oncologic diseases may develop and be treated differently from younger patients, leading to unique challenges in treatment efficacy and tolerance. To overcome this challenge, personalized therapy using biomarkers has emerged as a promising solution. Various categories of biomarkers, including inflammatory, hematological, metabolic, endocrine, and DNA modification-related indicators, may display features related to both cancer and aging, aiding in the development of innovative therapeutic approaches for patients with cancer in old age. Furthermore, physical functional measurements as non-molecular phenotypic biomarkers are being investigated for their potential complementary role in structured multidomain strategies to combat age-related diseases such as cancer. This review provides insight into the current developments, recent discoveries, and significant challenges in cancer and aging biomarkers, with a specific focus on their application in advanced age.

20.
Cancers (Basel) ; 15(24)2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38136299

RESUMEN

Patient-derived xenograft (PDX) tumor models are essential for identifying new biomarkers, signaling pathways and novel targets, to better define key factors of therapy response and resistance mechanisms. Therefore, this study aimed at establishing pancreas carcinoma (PC) PDX models with thorough molecular characterization, and the identification of signatures defining responsiveness toward drug treatment. In total, 45 PC-PDXs were generated from 120 patient tumor specimens and the identity of PDX and corresponding patient tumors was validated. The majority of engrafted PDX models represent ductal adenocarcinomas (PDAC). The PDX growth characteristics were assessed, with great variations in doubling times (4 to 32 days). The mutational analyses revealed an individual mutational profile of the PDXs, predominantly showing alterations in the genes encoding KRAS, TP53, FAT1, KMT2D, MUC4, RNF213, ATR, MUC16, GNAS, RANBP2 and CDKN2A. Sensitivity of PDX toward standard of care (SoC) drugs gemcitabine, 5-fluorouracil, oxaliplatin and abraxane, and combinations thereof, revealed PDX models with sensitivity and resistance toward these treatments. We performed correlation analyses of drug sensitivity of these PDX models and their molecular profile to identify signatures for response and resistance. This study strongly supports the importance and value of PDX models for improvement in therapies of PC.

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