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1.
Gut ; 72(2): 325-337, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35705369

RESUMEN

OBJECTIVE: Programmed cell death protein 1 (PD-1) checkpoint inhibition and adoptive cellular therapy have had limited success in patients with microsatellite stable colorectal cancer liver metastases (CRLM). We sought to evaluate the effect of interleukin 10 (IL-10) blockade on endogenous T cell and chimeric antigen receptor T (CAR-T) cell antitumour function in CRLM slice cultures. DESIGN: We created organotypic slice cultures from human CRLM (n=38 patients' tumours) and tested the antitumour effects of a neutralising antibody against IL-10 (αIL-10) both alone as treatment and in combination with exogenously administered carcinoembryonic antigen (CEA)-specific CAR-T cells. We evaluated slice cultures with single and multiplex immunohistochemistry, in situ hybridisation, single-cell RNA sequencing, reverse-phase protein arrays and time-lapse fluorescent microscopy. RESULTS: αIL-10 generated a 1.8-fold increase in T cell-mediated carcinoma cell death in human CRLM slice cultures. αIL-10 significantly increased proportions of CD8+ T cells without exhaustion transcription changes, and increased human leukocyte antigen - DR isotype (HLA-DR) expression of macrophages. The antitumour effects of αIL-10 were reversed by major histocompatibility complex class I or II (MHC-I or MHC-II) blockade, confirming the essential role of antigen presenting cells. Interrupting IL-10 signalling also rescued murine CAR-T cell proliferation and cytotoxicity from myeloid cell-mediated immunosuppression. In human CRLM slices, αIL-10 increased CEA-specific CAR-T cell activation and CAR-T cell-mediated cytotoxicity, with nearly 70% carcinoma cell apoptosis across multiple human tumours. Pretreatment with an IL-10 receptor blocking antibody also potentiated CAR-T function. CONCLUSION: Neutralising the effects of IL-10 in human CRLM has therapeutic potential as a stand-alone treatment and to augment the function of adoptively transferred CAR-T cells.


Asunto(s)
Carcinoma , Neoplasias Colorrectales , Interleucina-10 , Neoplasias Hepáticas , Receptores Quiméricos de Antígenos , Receptores de Interleucina-10 , Animales , Humanos , Ratones , Antígeno Carcinoembrionario/inmunología , Carcinoma/inmunología , Carcinoma/secundario , Linfocitos T CD8-positivos/inmunología , Neoplasias Colorrectales/patología , Inmunoterapia Adoptiva , Interleucina-10/antagonistas & inhibidores , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/secundario , Activación de Linfocitos , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores Quiméricos de Antígenos/genética , Receptores Quiméricos de Antígenos/metabolismo , Receptores de Interleucina-10/antagonistas & inhibidores , Anticuerpos Bloqueadores/inmunología
2.
Entropy (Basel) ; 25(8)2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37628165

RESUMEN

In this paper, we put forward the model of multiple linear-combination security multicast network coding, where the wiretapper desires to obtain some information about a predefined set of multiple linear combinations of the source symbols by eavesdropping any one (but not more than one) channel subset up to a certain size r, referred to as the security level. For this model, the security capacity is defined as the maximum average number of source symbols that can be securely multicast to all sink nodes for one use of the network under the linear-combination security constraint. For any security level and any linear-combination security constraint, we fully characterize the security capacity in terms of the ratio of the rank of the linear-combination security constraint to the number of source symbols. Also, we develop a general construction of linear security network codes. Finally, we investigate the asymptotic behavior of the security capacity for a sequence of linear-combination security models and discuss the asymptotic optimality of our code construction.

3.
Surg Endosc ; 36(2): 889-895, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-33608766

RESUMEN

BACKGROUND: Robotic hepatectomy (RH) is increasingly utilized for minor and major liver resections. The IWATE criteria were developed to classify minimally invasive liver resections by difficulty. The objective of this study was to apply the IWATE criteria in RH and to describe perioperative and oncologic outcomes of RH over the last decade at our institution. METHODS: Perioperative and oncologic outcomes of patients who underwent RH between 2011 and 2019 were retrospectively collected. The difficulty level of each operation was assessed using the IWATE criteria, and outcomes were compared at each level. Univariate linear regression was performed to characterize the relationship between IWATE criteria and perioperative outcomes (OR time, EBL, and LOS), and a multivariable model was also developed to address potential confounding by patient characteristics (age, sex, BMI, prior abdominal surgery, ASA class, and simultaneous non-hepatectomy operation). RESULTS: Two hundred and twenty-five RH were performed. Median IWATE criteria for RH were 6 (IQR 5-9), with low, intermediate, advanced, and expert resections accounting for 23% (n = 51), 34% (n = 77), 32% (n = 72), and 11% (n = 25) of resections, respectively. The majority of resections were parenchymal-sparing approaches, including anatomic segmentectomies and non-anatomic partial resections. 30-day complication rate was 14%, conversion to open surgery occurred in 9 patients (4%), and there were no deaths within 30 days postoperatively. In the univariate linear regression analysis, IWATE criteria were positively associated with OR time, EBL, and LOS. In the multivariable model, IWATE criteria were independently associated with greater OR time, EBL, and LOS. Two-year overall survival for hepatocellular carcinoma and intrahepatic cholangiocarcinoma was 94% and 50%, respectively. CONCLUSION: In conclusion, the IWATE criteria are associated with surgical outcomes after RH. This series highlights the utility of RH for difficult hepatic resections, particularly parenchymal-sparing resections in the posterosuperior sector, extending the indication of minimally invasive hepatectomy in experienced hands and potentially offering select patients an alternative to open hepatectomy or other less definitive liver-directed treatment options.


Asunto(s)
Neoplasias de los Conductos Biliares , Laparoscopía , Neoplasias Hepáticas , Procedimientos Quirúrgicos Robotizados , Neoplasias de los Conductos Biliares/cirugía , Conductos Biliares Intrahepáticos/patología , Hepatectomía/efectos adversos , Humanos , Laparoscopía/efectos adversos , Tiempo de Internación , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Estudios Retrospectivos , Procedimientos Quirúrgicos Robotizados/efectos adversos
4.
Cell Immunol ; 360: 104275, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33421676

RESUMEN

The liver contains a rich mix of T cells, including activated T cells, tissue-resident memory T cells and cells undergoing apoptosis. When antigens are presented in this milieu the default result is functional tolerance. T cell tolerance in the liver could be constitutive, or it could be adaptive, in which case liver cells would become unresponsive after encountering antigen in the liver context. To test this model, we evaluated the potential of human liver T cells to respond to T cell receptor ligation in liver tissue slice cultures. These T cells contained an actively motile subset of CD4+ T cells marked by CCR7 and CD62L, and fully functional subsets of CD4+ and CD8+ T cells that synthesized effector cytokines but subsequently assumed an exhausted phenotype. These data favor the model that human liver T cells are not constitutively tolerant but undergo adaptive tolerance after activation.


Asunto(s)
Tolerancia Inmunológica/inmunología , Hígado/inmunología , Linfocitos T/metabolismo , Inmunidad Adaptativa/inmunología , Antígenos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Diferenciación Celular/inmunología , Humanos , Memoria Inmunológica/inmunología , Hígado/patología , Activación de Linfocitos/inmunología , Fenotipo , Subgrupos de Linfocitos T/inmunología , Linfocitos T/inmunología
5.
Cell Tissue Bank ; 21(1): 89-97, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31838727

RESUMEN

Precision tissue diagnostics rely on high quality input specimens so that assay results are not affected by artifact, but advances in collection and processing of tissue specimens have lagged behind innovations in diagnostic assay development. Therefore, we have designed and evaluated a novel surgical tissue collection device that maintains and monitors sample temperature and motion throughout transport so that the major preanalytical variable of tissue temperature can be controlled and measured. This device, in combination with an improved cold-hot tissue fixation protocol affords optimal biomarker preservation in less overall time, thereby simultaneously improving diagnostic quality and turnaround time. We collected 50 primary and metastatic liver tumors using a novel transport device. Tissue was fixed using a rapid cold-hot fixation protocol and immunohistochemical assays were used to assess the performance of the device, in comparison to control tissue preserved using standard clinical fixation protocol. Two pathologists evaluated the IHC studies in a blinded fashion to determine the immunophenotype of each tumor. The observed IHC staining intensities and the clinical impressions of the immunophenotypes did not differ between tissue collected with the novel device and control tissue, while improvements in processing time were achieved. The novel cold transport device and rapid fixation protocol can be successfully and safely combined and used to monitor specimen conditions, thus preserving the diagnostic utility of specimens and improving the overall turn-around time of the diagnostic process.


Asunto(s)
Biomarcadores de Tumor/análisis , Biopsia/instrumentación , Neoplasias/patología , Fijación del Tejido/instrumentación , Conservación de Tejido/instrumentación , Biopsia/economía , Frío , Diseño de Equipo , Humanos , Inmunohistoquímica , Temperatura , Factores de Tiempo , Fijación del Tejido/economía , Conservación de Tejido/economía
6.
Entropy (Basel) ; 22(7)2020 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-33286561

RESUMEN

Internet of Things (IoT) connects billions of everyday objects to the Internet. The mobility of devices can be facilitated by means of employing multiple wireless links. However, packet loss is a common phenomenon in wireless communications, where the traditional forwarding strategy undergoes severe performance issues in a multi-hop wireless network. One solution is to apply batched sparse (BATS) codes. A fundamental difference from the traditional strategy is that BATS codes require the intermediate network nodes to perform recoding, which generates recoded packets by network coding operations. Literature showed that advanced recoding schemes and burst packet loss can enhance and diminish the performance of BATS codes respectively. However, the existing protocols for BATS codes cannot handle both of them at the same time. In this paper, we propose a paradigm of protocol design for BATS codes. Our design can be applied in different layers of the network stack and it is compatible to the existing network infrastructures. The modular nature of the protocol can support different recoding techniques and different ways to handle burst packet loss. We also give some examples to demonstrate how to use the protocol.

7.
Hepatology ; 67(2): 636-650, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28913935

RESUMEN

Hepatocellular carcinomas (HCC) contain a subpopulation of cancer stem cells (CSCs), which exhibit stem cell-like features and are responsible for tumor relapse, metastasis, and chemoresistance. The development of effective treatments for HCC will depend on a molecular-level understanding of the specific pathways driving CSC emergence and stemness. MacroH2A1 is a variant of the histone H2A and an epigenetic regulator of stem-cell function, where it promotes differentiation and, conversely, acts as a barrier to somatic-cell reprogramming. Here, we focused on the role played by the histone variant macroH2A1 as a potential epigenetic factor promoting CSC differentiation. In human HCC sections we uncovered a significant correlation between low frequencies of macroH2A1 staining and advanced, aggressive HCC subtypes with poorly differentiated tumor phenotypes. Using HCC cell lines, we found that short hairpin RNA-mediated macroH2A1 knockdown induces acquisition of CSC-like features, including the growth of significantly larger and less differentiated tumors when injected into nude mice. MacroH2A1-depleted HCC cells also exhibited reduced proliferation, resistance to chemotherapeutic agents, and stem-like metabolic changes consistent with enhanced hypoxic responses and increased glycolysis. The loss of macroH2A1 increased expression of a panel of stemness-associated genes and drove hyperactivation of the nuclear factor kappa B p65 pathway. Blocking phosphorylation of nuclear factor kappa B p65 on Ser536 inhibited the emergence of CSC-like features in HCC cells knocked down for macroH2A1. Conclusion: The absence of histone variant macroH2A1 confers a CSC-like phenotype to HCC cells in vitro and in vivo that depends on Ser536 phosphorylation of nuclear factor kappa B p65; this pathway may hold valuable targets for the development of CSC-focused treatments for HCC. (Hepatology 2018;67:636-650).


Asunto(s)
Carcinoma Hepatocelular/patología , Histonas/fisiología , Neoplasias Hepáticas/patología , Células Madre Neoplásicas/patología , Proliferación Celular , Perfilación de la Expresión Génica , Células Hep G2 , Humanos , Fosforilación , Factor de Transcripción ReIA/metabolismo
8.
Exp Physiol ; 103(11): 1469-1480, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30117227

RESUMEN

NEW FINDINGS: What is the central question of this study? Whether chronic oral rapamycin promotes beneficial effects on glucose/lipid metabolism and energy balance when administered to mice with an obesogenic diet rich in saturated fat and sucrose has not been explored. What is the main finding and its importance? Chronic oral rapamycin reduces body weight and fat gain, improves insulin sensitivity and reduces hepatic steatosis when administered to mice with a high-fat, high-sucrose diet. In addition, we make the new observation that there appear to be tissue-specific effects of rapamycin. Although rapamycin appears to impart its effects mainly on visceral adipose tissue, its effects on insulin sensitivity are mediated by subcutaneous adipose tissue. ABSTRACT: Excess adiposity is commonly associated with insulin resistance, which can increase the risk of cardiovascular disease. However, the exact molecular mechanisms by which obesity results in insulin resistance are yet to be understood clearly. The intracellular nutrient-sensing protein, mechanistic target of rapamycin (mTOR), is a crucial signalling component in the development of obesity-associated insulin resistance. Given that increased tissue activation of mTOR complex-1 (mTORC1) occurs in obesity, diabetes and ageing, we hypothesized that pharmacological inhibition of mTORC1 would improve metabolic dysregulation in diet-induced obesity. We administered continuous rapamycin, a specific mTORC1 inhibitor, orally to C57BL/6J mice concurrently with a high-fat, high-sucrose (HFHS) diet for 20 weeks. The control group received placebo microcapsules. Rapamycin-treated mice showed significantly reduced weight gain and adiposity (33.6 ± 4.9 versus 40.4 ± 3.0% body fat, P < 0.001, n = 8 mice per group), despite increased or equivalent food intake compared with the placebo group. The rapamycin-fed mice also demonstrated reduced plasma glucose (252 ± 57 versus 297 ± 67 mg dl-1 , P < 0.001) and improved insulin sensitivity during insulin and glucose tolerance testing. Rapamycin-treated mice also had lower plasma triglycerides (48 ± 13 versus 67 ± 11 mg/dL, P < 0.01) and hepatic triglyceride content (89 ± 15 versus 110 ± 19 mg/g liver, P < 0.05) compared with the placebo group. A moderately low dose of rapamycin decreased adiposity and improved the metabolic profile in a model of diet-induced obesity. These data suggest that low-grade chronic mTORC1 inhibition might be a potential strategy for anti-obesity therapies.


Asunto(s)
Adiposidad/efectos de los fármacos , Grasas de la Dieta , Sacarosa en la Dieta , Resistencia a la Insulina/fisiología , Hígado/efectos de los fármacos , Sirolimus/farmacología , Triglicéridos/metabolismo , Animales , Glucemia , Peso Corporal/efectos de los fármacos , Metabolismo de los Lípidos/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones
9.
Radiology ; 278(1): 285-94, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26523493

RESUMEN

PURPOSE: To assess the postprocedure findings of irreversible electroporation (IRE) in patients with hepatocellular carcinoma (HCC) at magnetic resonance (MR) imaging. MATERIALS AND METHODS: This retrospective study was Institutional Review Board approved, and informed consent was waived. Twenty patients with HCC were treated with IRE over a 2.5-year period. The median patient age was 62 years, and 75% of patients had cirrhosis with a Child-Pugh score of A. The median tumor diameter was 2.0 cm (range, 1.0-3.3 cm). Contrast material-enhanced multiphase MR imaging was performed on postprocedure days 1 and 30 and every 90 days thereafter. Ablation zone sizes and signal intensities were compared between each time point for both T1- and T2-weighted images. Trends in signal intensity and tumor dimensions over time were quantified by using generalized linear models. RESULTS: MR imaging appearances of treated tumors include a zone of peripheral enhancement with centripetal filling on delayed contrast-enhanced images. Compared with postprocedure day 1, every 90 days there is a decrease of 28.9% (mean, axis) in the size of the enhancing ablation zone. Over time, there is a trend toward decreasing signal intensity in the peripheral ablation zone on both T2-weighted (P = .01) and contrast-enhanced T1-weighted (P < .08) images. Conversely, the tumor itself typically has increased signal intensity on the same sequences. CONCLUSION: IRE of HCC results in a large region of enhancement on immediate postprocedure MR images that, over time, involutes and is associated with decreasing signal intensity of the peripheral ablation zone. This phenomenon may represent resolution of the reversible penumbra.


Asunto(s)
Carcinoma Hepatocelular/patología , Electroporación/métodos , Neoplasias Hepáticas/patología , Imagen por Resonancia Magnética/métodos , Anciano , Medios de Contraste , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
10.
Pediatr Res ; 80(1): 110-8, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27027723

RESUMEN

BACKGROUND: Fibrolamellar hepatocellular carcinoma (FL-HCC) affects children without underlying liver disease. A consistent mutation in FL-HCCs leads to fusion of the genes encoding a heat shock protein (DNAJB1) and the catalytic subunit of protein kinase A (PRKACA). We sought to characterize the resultant chimeric protein and its effects in FL-HCC. METHODS: The expression pattern and subcellular localization of protein kinase A (PKA) subunits in FL-HCCs were compared to paired normal livers by quantitative polymerase chain reaction (qPCR), immunoblotting, and immunofluorescence. PKA activity was measured by radioactive kinase assay, and we determined whether the FL-HCC mutation is present in other primary liver tumors. RESULTS: The fusion transcript and chimeric protein were detected exclusively in FL-HCCs. DNAJB1-PRKACA was expressed 10-fold higher than the wild-type PRKACA transcript, resulting in overexpression of the mutant protein in tumors. Consequently, FL-HCCs possess elevated cAMP-stimulated PKA activity compared to normal livers, despite similar Kms between the mutant and wild-type kinases. CONCLUSION: FL-HCCs in children and young adults uniquely overexpress DNAJB1-PRKACA, which results in elevated cAMP-dependent PKA activity. These data suggest that aberrant PKA signaling contributes to liver tumorigenesis.


Asunto(s)
8-Bromo Monofosfato de Adenosina Cíclica/análogos & derivados , Carcinoma Hepatocelular/enzimología , Subunidades Catalíticas de Proteína Quinasa Dependientes de AMP Cíclico/genética , Neoplasias Hepáticas/enzimología , Mutación , 8-Bromo Monofosfato de Adenosina Cíclica/metabolismo , Carcinoma Hepatocelular/genética , Dominio Catalítico , AMP Cíclico/metabolismo , Relación Dosis-Respuesta a Droga , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/genética , Metástasis Linfática , Recurrencia Local de Neoplasia
11.
Pediatr Blood Cancer ; 63(7): 1163-7, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26990031

RESUMEN

Fibrolamellar hepatocellular carcinoma (FL-HCC) has historically been classified as a rare subtype of HCC. However, unlike "classic" HCC, it occurs in children and young adults without underlying liver disease. The recent discovery of a deletion mutation in all FL-HCCs represented a major advancement in understanding the pathogenesis of this disease. This deletion results in the fusion of the genes encoding a heat shock protein (DNAJB1) and the catalytic subunit of protein kinase A (PKA, PRKACA), and overexpression of PRKACA and enhanced cAMP-dependent PKA activity. This review summarizes recent advancements in FL-HCC pathogenesis and characteristics of the HSP40-PKA C protein.


Asunto(s)
Secuencia de Bases , Carcinoma Hepatocelular/genética , Subunidades Catalíticas de Proteína Quinasa Dependientes de AMP Cíclico/genética , Proteínas del Choque Térmico HSP40/genética , Neoplasias Hepáticas/genética , Proteínas de Fusión Oncogénica/genética , Eliminación de Secuencia , Adolescente , Adulto , Carcinoma Hepatocelular/clasificación , Carcinoma Hepatocelular/patología , Niño , Preescolar , Femenino , Humanos , Neoplasias Hepáticas/clasificación , Neoplasias Hepáticas/patología , Masculino
12.
Mod Pathol ; 28(1): 103-10, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24925055

RESUMEN

Fibrolamellar hepatocellular carcinoma, or fibrolamellar carcinoma, is a rare form of primary liver cancer that afflicts healthy young men and women without underlying liver disease. There are currently no effective treatments for fibrolamellar carcinoma other than resection or transplantation. In this study, we sought evidence of mechanistic target of rapamycin complex 1 (mTORC1) activation in fibrolamellar carcinoma, based on anecdotal reports of tumor response to rapamycin analogs. Using a tissue microarray of 89 primary liver tumors, including a subset of 10 fibrolamellar carcinomas, we assessed the expression of phosphorylated S6 ribosomal protein (P-S6), a downstream target of mTORC1, along with fibroblast growth factor receptor 1 (FGFR1). These results were extended and confirmed using an additional 13 fibrolamellar carcinomas, whose medical records were reviewed. In contrast to weak staining in normal livers, all fibrolamellar carcinomas on the tissue microarray showed strong immunostaining for FGFR1 and P-S6, whereas only 13% of non-fibrolamellar hepatocellular carcinomas had concurrent activation of FGFR1 and mTORC1 signaling (P<0.05). When individual samples were stratified according to staining intensity (scale 0-4), the average score in fibrolamellar carcinomas was 2.46 for FGFR1 and 3.77 for P-S6, compared with 0 and 0, respectively, in non-tumor liver. Immunoblot analyses of fibrolamellar carcinomas revealed high mTORC1 activities relative to AKT activities accompanied by reduced TSC2 expression, which was not observed in non-fibrolamellar hepatocellular carcinomas. Our findings provide evidence for mTORC1 activation and FGFR1 overexpression in human fibrolamellar carcinoma, and support the use of FGFR1 inhibitors and rapamycin analogs in the treatment of patients with unresectable fibrolamellar carcinoma.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Complejos Multiproteicos/metabolismo , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Adolescente , Adulto , Femenino , Humanos , Immunoblotting , Inmunohistoquímica , Masculino , Diana Mecanicista del Complejo 1 de la Rapamicina , Análisis de Matrices Tisulares , Adulto Joven
13.
Gastroenterology ; 144(5): 1055-65, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23376645

RESUMEN

BACKGROUND & AIMS: Phosphatidylinositide 3-kinase (PI3K) is deregulated in many human tumor types, including primary liver malignancies. The kinase v-akt murine thymoma viral oncogene homolog 1 (Akt) and mammalian target of rapamycin complex (mTORC1) are effectors of PI3K that promote cell growth and survival, but their individual roles in tumorigenesis are not well defined. METHODS: In livers of albumin (Alb)-Cre mice, we selectively deleted tuberous sclerosis (Tsc)1, a negative regulator of Ras homolog enriched in brain and mTORC1, along with Phosphatase and tensin homolog (Pten), a negative regulator of PI3K. Tumor tissues were characterized by histologic and biochemical analyses. RESULTS: The Tsc1fl/fl;AlbCre, Ptenfl/fl;AlbCre, and Tsc1fl/fl;Ptenfl/fl;AlbCre mice developed liver tumors that differed in size, number, and histologic features. Livers of Tsc1fl/fl;AlbCre mice did not develop steatosis; tumors arose later than in the other strains of mice and were predominantly hepatocellular carcinomas. Livers of the Ptenfl/fl;AlbCre mice developed steatosis and most of the tumors that formed were intrahepatic cholangiocarcinomas. Livers of Tsc1fl/fl;Ptenfl/fl;AlbCre formed large numbers of tumors, of mixed histologies, with the earliest onset of any strain, indicating that loss of Tsc1 and Pten have synergistic effects on tumorigenesis. In these mice, the combination of rapamycin and MK2206 was more effective in reducing liver cell proliferation and inducing cell death than either reagent alone. Tumor differentiation correlated with Akt and mTORC1 activities; the ratio of Akt:mTORC1 activity was high throughout the course of intrahepatic cholangiocarcinomas development and low during hepatocellular carcinoma development. Compared with surrounding nontumor liver tissue, tumors from all 3 strains had increased activities of Akt, mTORC1, and mitogen-activated protein kinase and overexpressed fibroblast growth factor receptor 1. Inhibition of fibroblast growth factor receptor 1 in Tsc1-null mice suppressed Akt and mitogen-activated protein kinase activities in tumor cells. CONCLUSIONS: Based on analyses of knockout mice, mTORC1 and Akt have different yet synergistic effects during the development of liver tumors in mice.


Asunto(s)
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas Experimentales/genética , Complejos Multiproteicos/genética , Mutación , Proteínas Proto-Oncogénicas c-akt/genética , ARN Neoplásico/genética , Serina-Treonina Quinasas TOR/genética , Animales , Western Blotting , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas Experimentales/metabolismo , Neoplasias Hepáticas Experimentales/patología , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones , Ratones Noqueados , Complejos Multiproteicos/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Serina-Treonina Quinasas TOR/metabolismo , Células Tumorales Cultivadas
14.
Invest Radiol ; 59(4): 337-344, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37725492

RESUMEN

OBJECTIVE: The aim of this study is to describe a comprehensive contrast-enhanced ultrasound (CEUS) imaging protocol and analysis method to implement CEUS LI-RADS (Liver Imaging Reporting and Data System) in a quantifiable manner. The methods that are validated with a prospective single-center study aim to simplify CEUS LI-RADS evaluation, remove observer bias, and potentially improve the sensitivity of CEUS LI-RADS. MATERIALS AND METHODS: This prospective single-center study enrolled patients with hepatocellular carcinoma (April 2021-June 2022; N = 31; mean age ± SD, 67 ± 6 years; 24 men/7 women). For each patient, at least 2 CEUS loops spanning over 5 minutes were collected for different lesion scan planes using an articulated arm to hold the transducer. Automatic respiratory gating and motion compensation algorithms removed errors due to breathing motion. The long axis of the lesion was measured in the contrast and fundamental images to capture nodule size. Parametric processing of time-intensity curve analysis on linearized data provided quantifiable information of the wash-in and washout dynamics via rise time ( RT ) and degree of washout ( DW ) parameters extracted from the time-intensity curve, respectively. A Welch t test was performed between lesion and parenchyma RT for each lesion to confirm statistically significant differences. P values for bootstrapped 95% confidence intervals of the relative degree of washout ( rDW ), ratio of DW between the lesion and surrounding parenchyma, were computed to quantify lesion washout. Coefficient of variation (COV) of RT , DW , and rDW was calculated for each patient between injections for both the lesion and surrounding parenchyma to gauge reproducibility of these metrics. Spearman rank correlation tests were performed among size, RT , DW , and rDW values to evaluate statistical dependence between the variables. RESULTS: The mean ± SD lesion diameter was 23 ± 8 mm. The RT for all lesions, capturing arterial phase hyperenhancement, was shorter than that of surrounding liver parenchyma ( P < 0.05). All lesions also demonstrated significant ( P < 0.05) but variable levels of washout at both 2-minute and 5-minute time points, quantified in rDW . The COV of RT for the lesion and surrounding parenchyma were both 11%, and the COV of DW and rDW at 2 and 5 minutes ranged from 22% to 31%. Statistically significant relationships between lesion and parenchyma RT and between lesion RT and lesion DW at the 2- and 5-minute time points were found ( P < 0.05). CONCLUSIONS: The imaging protocol and analysis method presented provide robust, quantitative metrics that describe the dynamic vascular patterns of LI-RADS 5 lesions classified as hepatocellular carcinomas. The RT of the bolus transit quantifies the arterial phase hyperenhancement, and the DW and rDW parameters quantify the washout from linearized CEUS intensity data. This unique methodology is able to implement the CEUS-LIRADS scheme in a quantifiable manner for the first time and remove its existing issues of currently being qualitative and suffering from subjective evaluations.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Masculino , Humanos , Femenino , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/patología , Estudios Prospectivos , Reproducibilidad de los Resultados , Medios de Contraste , Imagen por Resonancia Magnética/métodos , Ultrasonografía/métodos , Estudios Retrospectivos , Sensibilidad y Especificidad
15.
bioRxiv ; 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38352494

RESUMEN

Functional assays on intact tumor biopsies can potentially complement and extend genomics-based approaches for precision oncology, drug testing, and organs-on-chips cancer disease models by capturing key determinants of therapeutic response, such as tissue architecture, tumor heterogeneity, and the tumor microenvironment. Currently, most of these assays rely on fluorescent labeling, a semi-quantitative method best suited to be a single-time-point terminal assay or labor-intensive terminal immunostaining analysis. Here, we report integrated aptamer electrochemical sensors for on-chip, real-time monitoring of increases of cytochrome C, a cell death indicator, from intact microdissected tissues with high affinity and specificity. The platform features a multi-well sensor layout and a multiplexed electronic setup. The aptasensors measure increases in cytochrome C in the supernatant of mouse or human microdissected tumors after exposure to various drug treatments. Since the aptamer probe can be easily exchanged to recognize different targets, the platform could be adapted for multiplexed monitoring of various biomarkers, providing critical information on the tumor and its microenvironment. This approach could not only help develop more advanced cancer disease models but also apply to other complex in vitro disease models, such as organs-on-chips and organoids.

16.
Sci Adv ; 10(36): eadn5875, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39241078

RESUMEN

Functional assays on intact tumor biopsies can complement genomics-based approaches for precision oncology, drug testing, and organs-on-chips cancer disease models by capturing key therapeutic response determinants, such as tissue architecture, tumor heterogeneity, and the tumor microenvironment. Most of these assays rely on fluorescent labeling, a semiquantitative method best suited for single-time-point assays or labor-intensive immunostaining analysis. Here, we report integrated aptamer electrochemical sensors for on-chip, real-time monitoring of cytochrome C, a cell death indicator, from intact microdissected tissues with high affinity and specificity. The platform features a multi-well sensor layout and a multiplexed electronic setup. The aptasensors measure increases in cytochrome C in the supernatant of mouse or human microdissected tumors after exposure to various drug treatments. Because of the sensor's high affinity, it primarily tracks rising concentrations of cytochrome C, capturing dynamic changes during apoptosis. This approach could help develop more advanced cancer disease models and apply to other complex in vitro disease models, such as organs-on-chips and organoids.


Asunto(s)
Aptámeros de Nucleótidos , Citocromos c , Citocromos c/metabolismo , Humanos , Animales , Ratones , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Neoplasias/genética , Neoplasias/metabolismo , Técnicas Biosensibles/métodos , Biopsia , Línea Celular Tumoral , Apoptosis/efectos de los fármacos , Antineoplásicos/farmacología
17.
bioRxiv ; 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39345589

RESUMEN

The liver contains an intricate microstructure that is critical for liver function. Architectural disruption of this spatial structure is pathologic. Unfortunately, 2D histopathology - the gold standard for pathological understanding of many liver diseases - can misrepresent or leave gaps in our understanding of complex 3D structural features. Here, we utilized immunostaining, tissue clearing, microscopy, and computational software to create 3D multilobular reconstructions of both non-fibrotic and cirrhotic human liver tissue. We found that spatial architecture in human cirrhotic liver samples with varying etiologies had sinusoid zonation dysregulation, reduction in glutamine synthetase-expressing pericentral hepatocytes, regression of central vein networks, disruption of hepatic arterial networks, and fragmentation of biliary networks, which together suggest a pro-portalization/decentralization phenotype in cirrhotic tissue. Further implementation of 3D pathological analyses may provide a deeper understanding of cirrhotic pathobiology and inspire novel treatments for liver disease.

18.
bioRxiv ; 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-38585935

RESUMEN

Current cancer disease models fail to faithfully recapitulate key features of the human tumor microenvironment (TME), such as immune and vascular cells, while simultaneously enabling high-throughput drug tests. We have recently developed a precision slicing method that optimizes the yield of large numbers of cuboidal microtissues ("cuboids", ∼(400 µm) 3 ) from a single tumor biopsy. Here we demonstrate that cuboids from syngeneic mouse tumor models and human tumors retain a complex TME, making them amenable for drug and immunotherapy evaluation. We characterize relevant TME parameters, such as cellular architecture, cytokine secretion, proteomics profiles, and response to drug panels in multi-well arrays. Despite the cutting procedure and the time spent in culture (up to 7 days), the cuboids display strong cytokine and drug responses, including to immunotherapy. Overall, our results suggest that cuboids could provide invaluable therapeutic information for personalized oncology applications, and could help the development of TME-dependent therapeutics and cancer disease models, including for clinical trials.

19.
Cell Rep ; 43(2): 113678, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38236773

RESUMEN

The DNAJ-PKAc fusion kinase is a defining feature of fibrolamellar carcinoma (FLC). FLC tumors are notoriously resistant to standard chemotherapies, with aberrant kinase activity assumed to be a contributing factor. By combining proximity proteomics, biochemical analyses, and live-cell photoactivation microscopy, we demonstrate that DNAJ-PKAc is not constrained by A-kinase anchoring proteins. Consequently, the fusion kinase phosphorylates a unique array of substrates, including proteins involved in translation and the anti-apoptotic factor Bcl-2-associated athanogene 2 (BAG2), a co-chaperone recruited to the fusion kinase through association with Hsp70. Tissue samples from patients with FLC exhibit increased levels of BAG2 in primary and metastatic tumors. Furthermore, drug studies implicate the DNAJ-PKAc/Hsp70/BAG2 axis in potentiating chemotherapeutic resistance. We find that the Bcl-2 inhibitor navitoclax enhances sensitivity to etoposide-induced apoptosis in cells expressing DNAJ-PKAc. Thus, our work indicates BAG2 as a marker for advanced FLC and a chemotherapeutic resistance factor in DNAJ-PKAc signaling scaffolds.


Asunto(s)
Carcinoma Hepatocelular , Humanos , Supervivencia Celular , Carcinoma Hepatocelular/tratamiento farmacológico , Apoptosis , Proteínas HSP70 de Choque Térmico , Proteínas Proto-Oncogénicas c-bcl-2 , Chaperonas Moleculares
20.
bioRxiv ; 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-38586030

RESUMEN

The scarcity of human biopsies available for drug testing is a paramount challenge for developing new therapeutics, disease models, and personalized treatments. Microtechnologies that combine the microscale manipulation of tissues and fluids offer the exciting possibility of miniaturizing both disease models and drug testing workflows on scarce human biopsies. Unfortunately, these technologies presently require microfluidic devices or robotic dispensers that are not widely accessible. We have rapidly-prototyped an inexpensive platform based on an off-the-shelf robot that can microfluidically manipulate live microtissues into/out of culture plates without using complicated accessories such as microscopes or pneumatic controllers. The robot integrates complex functions with a simple, cost-effective and compact construction, allowing placement inside a tissue culture hood for sterile workflows. We demonstrated a proof-of-concept cancer drug evaluation workflow of potential clinical utility using patient tumor biopsies with multiple drugs on 384-well plates. Our user-friendly, low-cost platform promises to make drug testing of microtissues broadly accessible to pharmaceutical, clinical, and biological laboratories. Teaser: A low-cost robot for handling microtissues and catalyzing their use in cancer drug evaluation and personalized oncology.

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