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1.
Cancer Immunol Immunother ; 73(10): 204, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39105848

RESUMEN

The intricate interplay between immune and stromal cells within the tumour microenvironment (TME) significantly influences tumour progression. Myeloid cells, including tumour-associated macrophages (TAMs), neutrophils (TANs), and myeloid-derived suppressor cells (MDSCs), contribute to immune suppression in the TME (Nakamura and Smyth in Cell Mol Immunol 17(1):1-12 (2020). https://doi.org/10.1038/s41423-019-0306-1 ; DeNardo and Ruffell in Nat Rev Immunol 19(6):369-382 (2019). https://doi.org/10.1038/s41577-019-0127-6 ). This poses a significant challenge for novel immunotherapeutics that rely on host immunity to exert their effect. This systematic review explores the preclinical evidence surrounding the inhibition of phosphoinositide 3-kinase gamma (PI3Kγ) as a strategy to reverse myeloid-driven immune suppression in solid tumours. EMBASE, MEDLINE, and PubMed databases were searched on 6 October 2022 using keyword and subject heading terms to capture relevant studies. The studies, focusing on PI3Kγ inhibition in animal models, were subjected to predefined inclusion and exclusion criteria. Extracted data included tumour growth kinetics, survival endpoints, and immunological responses which were meta-analysed. PRISMA and MOOSE guidelines were followed. A total of 36 studies covering 73 animal models were included in the review and meta-analysis. Tumour models covered breast, colorectal, lung, skin, pancreas, brain, liver, prostate, head and neck, soft tissue, gastric, and oral cancer. The predominant PI3Kγ inhibitors were IPI-549 and TG100-115, demonstrating favourable specificity for the gamma isoform. Combination therapies, often involving chemotherapy, radiotherapy, immune checkpoint inhibitors, biological agents, or vaccines, were explored in 81% of studies. Analysis of tumour growth kinetics revealed a statistically significant though heterogeneous response to PI3Kγ monotherapy, whereas the tumour growth in combination treated groups were more consistently reduced. Survival analysis showed a pronounced increase in median overall survival with combination therapy. This systematic review provides a comprehensive analysis of preclinical studies investigating PI3Kγ inhibition in myeloid-driven tumour immune suppression. The identified studies underscore the potential of PI3Kγ inhibition in reshaping the TME by modulating myeloid cell functions. The combination of PI3Kγ inhibition with other therapeutic modalities demonstrated enhanced antitumour effects, suggesting a synergistic approach to overcome immune suppression. These findings support the potential of PI3Kγ-targeted therapies, particularly in combination regimens, as a promising avenue for future clinical exploration in diverse solid tumour types.


Asunto(s)
Neoplasias , Microambiente Tumoral , Humanos , Animales , Neoplasias/inmunología , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Microambiente Tumoral/inmunología , Fosfatidilinositol 3-Quinasa Clase Ib/metabolismo , Células Supresoras de Origen Mieloide/inmunología , Células Supresoras de Origen Mieloide/metabolismo , Células Mieloides/inmunología , Células Mieloides/metabolismo , Inmunoterapia/métodos , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3/uso terapéutico
2.
Mol Cell Proteomics ; 21(11): 100410, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36089194

RESUMEN

Little is known about the pathways regulating MHC antigen presentation and the identity of treatment-specific T cell antigens induced by ionizing radiation. For this reason, we investigated the radiation-specific changes in the colorectal tumor cell proteome. We found an increase in DDX58 and ZBP1 protein expression, two nucleic acid sensing molecules likely involved in induction of the dominant interferon response signature observed after genotoxic insult. We further observed treatment-induced changes in key regulators and effector proteins of the antigen processing and presentation machinery. Differential regulation of MHC allele expression was further driving the presentation of a significantly broader MHC-associated peptidome postirradiation, defining a radiation-specific peptide repertoire. Interestingly, treatment-induced peptides originated predominantly from proteins involved in catecholamine synthesis and metabolic pathways. A nuanced relationship between protein expression and antigen presentation was observed where radiation-induced changes in proteins do not correlate with increased presentation of associated peptides. Finally, we detected an increase in the presentation of a tumor-specific neoantigen derived from Mtch1. This study provides new insights into how radiation enhances antigen processing and presentation that could be suitable for the development of combinatorial therapies. Data are available via ProteomeXchange with identifier PXD032003.


Asunto(s)
Presentación de Antígeno , Proteoma , Proteoma/metabolismo , Péptidos/metabolismo , Proteómica , Radiación Ionizante
3.
Semin Cancer Biol ; 71: 143-156, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32526354

RESUMEN

Liver metastases from gastrointestinal and non-gastrointestinal malignancies remain a major cause of cancer-related mortality and a major clinical challenge. The liver has unique properties that facilitate metastatic expansion, including a complex immune system that evolved to dampen immunity to neoantigens entering the liver from the gut, through the portal circulation. In this review, we describe the unique microenvironment encountered by cancer cells in the liver, focusing on elements of the innate and adaptive immune response that can act as a double-edge sword, contributing to the elimination of cancer cells on the one hand and promoting their survival and growth, on the other. We discuss this microenvironment in a clinical context, particularly for colorectal carcinoma, and highlight how a better understanding of the role of the microenvironment has spurred an intense effort to develop novel and innovative strategies for targeting liver metastatic disease, some of which are currently being tested in the clinic.


Asunto(s)
Neoplasias Colorrectales/patología , Inmunidad , Neoplasias Hepáticas/secundario , Microambiente Tumoral , Animales , Neoplasias Colorrectales/inmunología , Humanos , Neoplasias Hepáticas/inmunología
4.
Br J Cancer ; 123(7): 1089-1100, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32641865

RESUMEN

BACKGROUND: Radiotherapy enhances innate and adaptive anti-tumour immunity. It is unclear whether this effect may be harnessed by combining immunotherapy with radiotherapy fractions used to treat prostate cancer. We investigated tumour immune microenvironment responses of pre-clinical prostate cancer models to radiotherapy. Having defined this landscape, we tested whether radiotherapy-induced tumour growth delay could be enhanced with anti-PD-L1. METHODS: Hypofractionated radiotherapy was delivered to TRAMP-C1 and MyC-CaP flank allografts. Tumour growth delay, tumour immune microenvironment flow-cytometry, and immune gene expression were analysed. TRAMP-C1 allografts were then treated with 3 × 5 Gy ± anti-PD-L1. RESULTS: 3 × 5 Gy caused tumour growth delay in TRAMP-C1 and MyC-CaP. Tumour immune microenvironment changes in TRAMP-C1 at 7 days post-radiotherapy included increased tumour-associated macrophages and dendritic cells and upregulation of PD-1/PD-L1, CD8+ T-cell, dendritic cell, and regulatory T-cell genes. At tumour regrowth post-3 × 5 Gy the tumour immune microenvironment flow-cytometry was similar to control tumours, however CD8+, natural killer and dendritic cell gene transcripts were reduced. PD-L1 inhibition plus 3 × 5 Gy in TRAMP-C1 did not enhance tumour growth delay versus monotherapy. CONCLUSION: 3 × 5 Gy hypofractionated radiotherapy can result in tumour growth delay and immune cell changes in allograft prostate cancer models. Adjuncts beyond immunomodulation may be necessary to improve the radiotherapy-induced anti-tumour response.


Asunto(s)
Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias de la Próstata/terapia , Hipofraccionamiento de la Dosis de Radiación , Microambiente Tumoral , Animales , Antígeno B7-H1/análisis , Línea Celular Tumoral , Terapia Combinada , Modelos Animales de Enfermedad , Antígenos de Histocompatibilidad Clase I/análisis , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Trasplante de Neoplasias , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/patología
5.
Dig Dis Sci ; 64(6): 1705-1710, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30617453

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is rare in patients with autoimmune hepatitis (AIH). However, the overall burden of AIH cirrhosis in causing HCC and patients' risk factors are not well understood. AIMS: To characterize the proportion of HCC linked to AIH at a large academic health center, and to identify variables associated with HCC in patients with AIH in a case-control study design. METHODS: Over a 14.5-year period, medical records of all patients with HCC were reviewed. Cases are AIH patients identified from the cohort, and controls are patients with AIH without HCC. Three controls were randomly chosen from the Genetic Repository of Autoimmune Liver Disease and Coexisting Exposures database for each eligible case. RESULTS: Out of 1250 eligible patients, 20 were linked to AIH (1.6%). Their median age was 64 years, 40% men and 100% Caucasian. Ten percent of AIH patients did not have evidence of cirrhosis at HCC diagnosis. The proportion of HCCs due to AIH decreased during the time intervals of the study. Compared to controls, cases were more likely men (40.0% vs. 18%, p = 0.049), with longer AIH duration (median 16 years vs. 5 years, p = 0.004). Prolonged AIH duration (OR 1.68, p = 0.006) and older age (OR 1.15, p = 0.049) were risk factors for HCC. CONCLUSIONS: AIH is a rare cause (1.6%) for HCC in Midwestern USA with a decreasing trend over 14.5 years. Ten percent of AIH-HCC patients did not have cirrhosis at time of HCC diagnosis. Patients with prolonged duration of the disease and older age are at high risk to develop HCC.


Asunto(s)
Carcinoma Hepatocelular/epidemiología , Hepatitis Autoinmune/epidemiología , Neoplasias Hepáticas/epidemiología , Factores de Edad , Anciano , Carcinoma Hepatocelular/diagnóstico , Estudios de Casos y Controles , Bases de Datos Factuales , Hepatitis Autoinmune/diagnóstico , Humanos , Indiana/epidemiología , Neoplasias Hepáticas/diagnóstico , Persona de Mediana Edad , Pronóstico , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo
6.
Hepatology ; 65(6): 1920-1935, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28133764

RESUMEN

Hepatic metastases are amenable to ablation; however, many patients are not suitable candidates for such therapy and recurrence is common. The tumor microenvironment is known to be essential for metastatic growth, yet identification of plausible targets for cancer therapy in the microenvironment has proven elusive. We found that human colorectal cancer liver metastases and murine gastrointestinal experimental liver metastases are infiltrated by neutrophils. Plasticity in neutrophils has recently been shown to lead to both protumor and antitumor effects. Here, neutrophils promoted the growth of hepatic metastases, given that depletion of neutrophils in already established, experimental, murine liver metastases led to diminished metastatic growth. Decreased growth was associated with reductions in vascular density and branching suggestive of vessel normalization. Metastasis-associated neutrophils expressed substantially more fibroblast growth factor 2 (FGF2) than naïve neutrophils, indicating neutrophil polarization by the tumor microenvironment. Administration of FGF2 neutralizing antibody to mice bearing experimental liver metastases phenocopied neutrophil depletion by reducing liver metastatic colony growth, vascular density, and branching. CONCLUSION: Here, we show, using FGF2 as an example, that identification of factors responsible for the protumoral effects of infiltrating myeloid cells can be used to target established liver metastases. Such therapies could be utilized to limit disease progression and potentiate the effects of standard ablative therapies. (Hepatology 2017;65:1920-1935).


Asunto(s)
Biomarcadores de Tumor/metabolismo , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Neovascularización Patológica/metabolismo , Animales , Biopsia con Aguja , Western Blotting , Neoplasias Colorrectales/patología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Femenino , Humanos , Inmunohistoquímica , Ratones , Ratones Endogámicos C57BL , Ratones SCID , Neoplasias Experimentales/patología , Neutrófilos/inmunología , Neoplasias Pancreáticas/patología , Distribución Aleatoria , Estadísticas no Paramétricas , Microambiente Tumoral/inmunología
7.
Hepatology ; 65(1): 174-188, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27641439

RESUMEN

Biliary atresia (BA) is a fibroinflammatory obstruction of the extrahepatic biliary tree in neonates. While intrahepatic bile duct proliferation is universal at diagnosis, bile duct paucity develops later. We hypothesized that polarized T helper lymphocyte responses orchestrate progression of intrahepatic biliary injury in this disease. Interleukin 17A (IL-17A)-green fluorescent protein, cluster of differentiation 11c (CD11c)/diphtheria toxin receptor, and IL-17 receptor A-/- mice were used to examine T-lymphocyte polarization, inflammatory leukocyte recruitment, and biliary injury in rhesus rotavirus-induced BA. Multiparameter flow cytometry and automated image analysis of immunostaining were applied to liver tissue samples from infants with BA. In the mouse model, activated CD4+ lymphocytes started to emerge in the liver on day 8 after viral challenge, while innate immune responses were waning. Plasma IL-17A levels rose concomitantly with hepatic accumulation of T helper 17 lymphocytes and myeloid dendritic cells. Targeted depletion of CD11c+ dendritic cells diminished hepatic IL-17A production and ameliorated intrahepatic bile duct injury. Recombinant IL-17A induced expression of chemokine (C-C motif) ligand 2 in neonatal cholangiocytes in vitro, and blockade of the corresponding chemokine (C-C motif) receptor 2 reduced recruitment of inflammatory macrophages to the liver in vivo. Genetic disruption of IL-17A signaling was associated with down-regulation of hepatic Ccl2/Ccr2 messenger RNA expression, reduced infiltration of the liver with inflammatory Ly6Chi macrophages, and improved survival. In the liver of infants with BA, cholangiocytes were found to express IL-17 receptor A, and the prevalence of IL-17A+ cells was positively correlated with the degree of CD68+ macrophage infiltration at diagnosis. Hepatic CD4+ lymphocytes were chief producers of IL-17A in patients with progressive disease undergoing liver transplantation. CONCLUSION: These findings identify the dendritic cell-T helper 17-macrophage axis as a target for the development of strategies to block progression of intrahepatic bile duct injury in patients with BA. (Hepatology 2017;65:174-188).


Asunto(s)
Atresia Biliar/inmunología , Células Dendríticas/fisiología , Macrófagos/fisiología , Células Th17/fisiología , Animales , Conductos Biliares Intrahepáticos/citología , Progresión de la Enfermedad , Células Epiteliales/patología , Humanos , Ratones , Ratones Endogámicos BALB C
8.
J Surg Oncol ; 118(3): 431-439, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30076741

RESUMEN

BACKGROUND AND OBJECTIVES: Hepatocellular carcinoma (HCC) in patients with hepatitis B virus (HBV) exhibit lower tumor microRNA-26a (miR-26a) expression which is associated with worse outcomes. It is unknown if similar miR-26a loss occurs in HCC developed in other liver diseases. We examined tumor miR-26a expression and its impact on recurrence and mortality in a North American HCC cohort. METHODS: MiR-26a levels from tumor and surrounding nontumor liver tissue in 186 subjects were collected. We defined lower tumor expression of miR-26a as <1-fold that of the adjacent nontumor liver tissue. RESULTS: Viral hepatitis (42%; 40% hepatitis C and 2% HBV), alcohol (19%), and nonalcoholic fatty liver disease (NAFLD) (18%) were the most common causes of liver disease. The prevalence of lower tumor miR-26a expression was 68%, and it was evident in HCCs arising in all etiologies (viral hepatitis 60%, alcohol 61%, and NAFLD 76%). Subjects with lower tumor miR-26a expression had significantly higher tumor recurrence (hazard ratio [HR], 2.45; 95% confidence interval [CI], 1.18 to 5.1; P = 0.016) and higher mortality of borderline significance (HR, 1.51; 95% CI, 0.94 to 2.41; P = 0.086). CONCLUSION: Reduced miR-26a expression is a common phenomenon in HCC arising in North American patients with different underlying liver diseases and may increase recurrence and mortality after surgery.


Asunto(s)
Biomarcadores de Tumor/sangre , Carcinoma Hepatocelular/cirugía , Regulación Neoplásica de la Expresión Génica , Hepatectomía/métodos , Neoplasias Hepáticas/cirugía , MicroARNs/sangre , Recurrencia Local de Neoplasia/sangre , Anciano , Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/patología , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Hepáticas/patología , Masculino , MicroARNs/genética , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/genética , Pronóstico , Transducción de Señal , Tasa de Supervivencia
9.
Br J Cancer ; 117(1): 124-135, 2017 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-28535157

RESUMEN

BACKGROUND: CXCL12 (SDF1) is reported to promote cancer progression in several preclinical models and this is corroborated by the analysis of human tissue specimens. However, the relationship between CXCL12 expression and cancer survival has not been systematically assessed. METHODS: We conducted a systematic review and meta-analysis of studies that evaluated the association between CXCL12 expression and cancer survival. RESULTS: Thirty-eight studies inclusive of 5807 patients were included in the analysis of overall, recurrence-free or cancer-specific survival, the majority of which were retrospective. The pooled hazard ratios (HRs) for overall and recurrence-free survival in patients with high CXCL12 expression were 1.39 (95% CI: 1.17-1.65, P=0.0002) and 1.12 (95% CI: 0.82-1.53, P=0.48) respectively, but with significant heterogeneity between studies. On subgroup analysis by cancer type, high CXCL12 expression was associated with reduced overall survival in patients with oesophagogastric (HR 2.08; 95% CI: 1.31-3.33, P=0.002), pancreatic (HR 1.54; 95% CI: 1.21-1.97, P=0.0005) and lung cancer (HR 1.37; 95% CI: 1.08-1.75, P=0.01), whereas in breast cancer patients high CXCL12 expression conferred an overall survival advantage (HR 0.5; 95% CI: 0.38-0.66, P<0.00001). CONCLUSIONS: Determination of CXCL12 expression has the potential to be of use as a cancer biomarker and adds prognostic information in various cancer types. Prospective or prospective-retrospective analyses of CXCL12 expression in clearly defined cancer cohorts are now required to advance our understanding of the relationship between CXCL12 expression and cancer outcome.


Asunto(s)
Quimiocina CXCL12/metabolismo , Neoplasias/metabolismo , Anticuerpos Monoclonales , Anticuerpos Monoclonales Humanizados , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/mortalidad , Supervivencia sin Enfermedad , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/mortalidad , Femenino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidad , Masculino , Neoplasias/mortalidad , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/mortalidad , Pronóstico , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/mortalidad , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidad , Tasa de Supervivencia
10.
World J Surg ; 41(9): 2266-2279, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28386715

RESUMEN

BACKGROUND: Individualised risk prediction is crucial if targeted pre-operative risk reduction strategies are to be deployed effectively. Radiologically determined sarcopenia has been shown to predict outcomes across a range of intra-abdominal pathologies. Access to pre-operative cross-sectional imaging has resulted in a number of studies investigating the predictive value of radiologically assessed sarcopenia over recent years. This systematic review and meta-analysis aimed to determine whether radiologically determined sarcopenia predicts post-operative morbidity and mortality following abdominal surgery. METHOD: CENTRAL, EMBASE and MEDLINE databases were searched using terms to capture the concept of radiologically assessed sarcopenia used to predict post-operative complications in abdominal surgery. Outcomes included 30 day post-operative morbidity and mortality, 1-, 3- and 5-year overall and disease-free survival and length of stay. Data were extracted and meta-analysed using either random or fixed effects model (Revman ® 5.3). RESULTS: A total of 24 studies involving 5267 patients were included in the review. The presence of sarcopenia was associated with a significant increase in major post-operative complications (RR 1.61 95% CI 1.24-4.15 p = <0.00001) and 30-day mortality (RR 2.06 95% CI 1.02-4.17 p = 0.04). In addition, sarcopenia predicted 1-, 3- and 5-year survival (RR 1.61 95% CI 1.36-1.91 p = <0.0001, RR 1.45 95% CI 1.33-1.58 p = <0.0001, RR 1.25 95% CI 1.11-1.42 p = 0.0003, respectively) and 1- and 3-year disease-free survival (RR 1.30 95% CI 1.12-1.52 p = 0.0008). CONCLUSION: Peri-operative cross-sectional imaging may be utilised in order to predict those at risk of complications following abdominal surgery. These findings should be interpreted in the context of retrospectively collected data and no universal sarcopenic threshold. Targeted prehabilitation strategies aiming to reverse sarcopenia may benefit patients undergoing abdominal surgery.


Asunto(s)
Abdomen/cirugía , Mortalidad , Complicaciones Posoperatorias/epidemiología , Sarcopenia/diagnóstico por imagen , Supervivencia sin Enfermedad , Humanos , Complicaciones Posoperatorias/mortalidad , Valor Predictivo de las Pruebas , Radiología , Factores de Riesgo , Sarcopenia/mortalidad , Tasa de Supervivencia
11.
Ann Surg ; 263(4): 656-63, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26501712

RESUMEN

OBJECTIVE: To systematically review studies reporting clinicopathological features of intraductal papillary neoplasm of the bile duct (IPNB) to provide evidence-based guidance for management. BACKGROUND: IPNB is a rare tumor type. Management decisions are currently based upon anecdotal evidence and small case series. To data, there has been no systematic review of IPNB literature. METHODS: MEDLINE, EMBASE, and the Cochrane Database of Systematic Reviews were searched and data were extracted from relevant studies. Meta-analysis was used to pool study estimates. Evidence of association was determined by comparing pooled crude odds ratios (OR) derived from abstracted data. RESULTS: Fifty-seven retrospective case series were included. At least 43% of 476 specimens contained invasive disease. Invasive tumors were found at significantly higher frequency in pancreaticobiliary than intestinal, gastric or oncocytic-type IPNB [pooled OR 2.5, 95% confidence interval (CI) 1.5-4.2, P < 0.001]. A significantly higher proportion of pancreaticobiliary tumors compared with intestinal tumors expressed MUC-1 [86.4% (95% CI 75.1%-94.7%) vs 13.2% (95% CI 4.6%-25.2%), respectively P < 0.001]. IPNB identified in centers from Asia were more likely to be intrahepatic and were less frequently invasive compared with those from Western centers. Pooled estimates of absolute survival after IPNB resection were 96% (95% CI 93%-99%) at 1 year, 79% (95% CI 69%-88%) at 3 years, and 65% (95% CI 46%-76%) at 5 years. CONCLUSIONS: Early surgery is advisable for radiologically suspected IPNB as it is frequently invasive. The pathobiology of IPNB demonstrates geographic variation. Pancreaticobiliary IPNB expresses MUC1 and is more frequently associated with invasive disease than other IPNB subtypes.


Asunto(s)
Neoplasias de los Conductos Biliares/cirugía , Neoplasias Quísticas, Mucinosas y Serosas/cirugía , Neoplasias de los Conductos Biliares/diagnóstico , Neoplasias de los Conductos Biliares/etiología , Neoplasias de los Conductos Biliares/mortalidad , Humanos , Neoplasias Quísticas, Mucinosas y Serosas/diagnóstico , Neoplasias Quísticas, Mucinosas y Serosas/etiología , Neoplasias Quísticas, Mucinosas y Serosas/mortalidad , Resultado del Tratamiento
12.
J Virol ; 89(18): 9440-53, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26136573

RESUMEN

UNLABELLED: Lipid-enveloped viruses replicate and bud from the host cell where they acquire their lipid coat. Ebola virus, which buds from the plasma membrane of the host cell, causes viral hemorrhagic fever and has a high fatality rate. To date, little has been known about how budding and egress of Ebola virus are mediated at the plasma membrane. We have found that the lipid phosphatidylserine (PS) regulates the assembly of Ebola virus matrix protein VP40. VP40 binds PS-containing membranes with nanomolar affinity, and binding of PS regulates VP40 localization and oligomerization on the plasma membrane inner leaflet. Further, alteration of PS levels in mammalian cells inhibits assembly and egress of VP40. Notably, interactions of VP40 with the plasma membrane induced exposure of PS on the outer leaflet of the plasma membrane at sites of egress, whereas PS is typically found only on the inner leaflet. Taking the data together, we present a model accounting for the role of plasma membrane PS in assembly of Ebola virus-like particles. IMPORTANCE: The lipid-enveloped Ebola virus causes severe infection with a high mortality rate and currently lacks FDA-approved therapeutics or vaccines. Ebola virus harbors just seven genes in its genome, and there is a critical requirement for acquisition of its lipid envelope from the plasma membrane of the human cell that it infects during the replication process. There is, however, a dearth of information available on the required contents of this envelope for egress and subsequent attachment and entry. Here we demonstrate that plasma membrane phosphatidylserine is critical for Ebola virus budding from the host cell plasma membrane. This report, to our knowledge, is the first to highlight the role of lipids in human cell membranes in the Ebola virus replication cycle and draws a clear link between selective binding and transport of a lipid across the membrane of the human cell and use of that lipid for subsequent viral entry.


Asunto(s)
Membrana Celular/metabolismo , Ebolavirus/fisiología , Fiebre Hemorrágica Ebola/metabolismo , Fosfatidilserinas/metabolismo , Ensamble de Virus/fisiología , Liberación del Virus/fisiología , Animales , Células CHO , Membrana Celular/patología , Membrana Celular/virología , Chlorocebus aethiops , Cricetulus , Células HEK293 , Fiebre Hemorrágica Ebola/patología , Humanos , Proteínas de la Matriz Viral/metabolismo
13.
Curr Protoc ; 4(10): e70032, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39432378

RESUMEN

Mouse models remain at the forefront of immuno-oncology research, providing invaluable insights into the complex interactions between the immune system and developing tumors. While several flow cytometry panels have been developed to study cancer immunity in mice, most are limited in their capacity to address the complexity of anti-cancer immune responses. For example, many of the panels developed to date focus on a restricted number of leukocyte populations (T cells or antigen-presenting cells), failing to include the multitude of other subsets that participate in anti-cancer immunity. In addition, these panels were developed using blood or splenic leukocytes. While the immune composition of the blood or spleen can provide information on systemic immune responses to cancer, it is in the tumor microenvironment (TME) that local immunity takes place. Therefore, we optimized this spectral flow cytometry panel to identify the chief cell types that take part in cancer immunity using immune cells from cancer tissue. We used pancreatic tumors implanted both orthotopically and subcutaneously to demonstrate the panel's flexibility and suitability in diverse mouse models. The panel was also validated in peripheral immune districts (the blood, spleen, and liver of tumor-bearing mice) to allow comparisons between local and systemic anti-tumor immunity. © 2024 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Tumor induction-Orthotopic Alternate Protocol: Tumor induction-Subcutaneous Basic Protocol 2: Preparation of single-cell suspensions from the tumor, spleen, liver, and blood of tumor-bearing mice Basic Protocol 3: Staining single-cell suspensions from the tumor, spleen, liver, and blood of tumor-bearing mice.


Asunto(s)
Modelos Animales de Enfermedad , Citometría de Flujo , Animales , Citometría de Flujo/métodos , Ratones , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/patología , Microambiente Tumoral/inmunología , Línea Celular Tumoral , Neoplasias/inmunología , Neoplasias/patología , Bazo/inmunología
14.
Dis Model Mech ; 17(3)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38421046

RESUMEN

The value of radiotherapy in the treatment of pancreatic cancer has been the subject of much debate but limited preclinical research. We hypothesise that the poor translation of radiation research into clinical trials of radiotherapy in pancreatic cancer is due, in part, to inadequate preclinical study models. Here, we developed and refined methods for targeted irradiation in autochthonous mouse models of pancreatic cancer, using a small animal radiotherapy research platform. We tested and optimised strategies for administration of contrast agents, iohexol and the liver imaging agent Fenestra LC, to enable the use of computed tomography imaging in tumour localisation. We demonstrate accurate tumour targeting, negligible off-target effects and therapeutic efficacy, depending on dose, number of fractions and tumour size, and provide a proof of concept that precise radiation can be delivered effectively to mouse pancreatic tumours with a clinically relevant microenvironment. This advance will allow investigation of the radiation response in murine pancreatic cancer, discovery of mechanisms and biomarkers of radiosensitivity or resistance, and development of radiosensitising strategies to inform clinical trials for precision radiotherapy in this disease.


Asunto(s)
Neoplasias Pancreáticas , Planificación de la Radioterapia Asistida por Computador , Animales , Ratones , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Neoplasias Pancreáticas/radioterapia , Modelos Animales de Enfermedad , Tomografía Computarizada por Rayos X/métodos , Microambiente Tumoral
15.
Br J Radiol ; 96(1147): 20220565, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36752570

RESUMEN

The limitation of the function of antitumour immune cells is a common hallmark of cancers that enables their survival. As such, the potential of immune checkpoint inhibition (ICI) acts as a paradigm shift in the treatment of a range of cancers but has not yet been fully capitalised. Combining minimally and non-invasive locoregional therapies offered by radiologists with ICI is now an active field of research with the aim of furthering therapeutic capabilities in medical oncology. In parallel to this impending advancement, the "imaging toolbox" available to radiologists is also growing, enabling more refined tumour characterisation as well as greater accuracy in evaluating responses to therapy. Options range from metabolite labelling to cellular localisation to immune checkpoint screening. It is foreseeable that these novel imaging techniques will be integrated into personalised treatment algorithms. This growth in the field must include updating the current standardised imaging criteria to ensure they are fit for purpose. Such criteria is crucial to both appropriately guide clinical decision-making regarding next steps of treatment, but also provide reliable prognosis. Quantitative approaches to these novel imaging techniques are also already being investigated to further optimise personalised therapeutic decision-making. The therapeutic potential of specific ICIs and locoregional therapies could be determined before administration thus limiting unnecessary side-effects whilst maintaining efficacy. Several radiological aspects of oncological care are advancing simultaneously. Therefore, it is essential that each development is assessed for clinical use and optimised to ensure the best treatment decisions are being offered to the patient. In this review, we discuss state of the art advances in novel functional imaging techniques in the field of immuno-oncology both pre-clinically and clinically.


Asunto(s)
Inhibidores de Puntos de Control Inmunológico , Inmunoterapia , Neoplasias , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Humanos , Neoplasias/diagnóstico por imagen , Neoplasias/radioterapia , Neoplasias/terapia , Radiología
16.
FEMS Microbes ; 3: xtac024, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37332508

RESUMEN

Pathogen surveillance within wastewater rapidly progressed during the SARS-CoV-2 pandemic and informed public health management. In addition to the successful monitoring of entire sewer catchment basins at the treatment facility scale, subcatchment or building-level monitoring enabled targeted support of resource deployment. However, optimizing the temporal and spatial resolution of these monitoring programs remains complex due to population dynamics and within-sewer physical, chemical, and biological processes. To address these limitations, this study explores the advancement of the building-scale network that monitored the on-campus residential population at the University of Colorado Boulder between August 2020 and May 2021 through a daily SARS-CoV-2 surveillance campaign. During the study period, SARS-CoV-2 infection prevalence transitioned from robust community spread in Fall 2020 to sporadic infections in Spring 2021. Temporally, these distinct phases enabled investigating the effectiveness of resource commitment by exploring subsets of the original daily sampling data. Spatially, select sampling sites were installed along the flow path of the pipe network, enabling the exploration of the conservation of viral concentrations within the wastewater. Infection prevalence and resource commitment for informed action displayed an inverted relationship: higher temporal and spatial resolution surveillance is more imperative during sporadic infection phases than during high prevalence periods. This relationship was reinforced when norovirus (two minor clusters) and influenza (primarily absent) were additionally surveilled at a weekly frequency. Overall, resource commitment should scale to meet the objectives of the monitoring campaign-providing a general prevalence estimate requires fewer resources than an early-warning and targeted-action monitoring framework.

18.
Nat Commun ; 11(1): 4064, 2020 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-32792542

RESUMEN

Regulation of the programming of tumour-associated macrophages (TAMs) controls tumour growth and anti-tumour immunity. We examined the role of FGF2 in that regulation. Tumours in mice genetically deficient in low-molecular weight FGF2 (FGF2LMW) regress dependent on T cells. Yet, TAMS not T cells express FGF receptors. Bone marrow derived-macrophages from Fgf2LMW-/- mice co-injected with cancer cells reduce tumour growth and express more inflammatory cytokines. FGF2 is induced in the tumour microenvironment following fractionated radiation in murine tumours consistent with clinical reports. Combination treatment of in vivo tumours with fractionated radiation and a blocking antibody to FGF2 prolongs tumour growth delay, increases long-term survival and leads to a higher iNOS+/CD206+ TAM ratio compared to irradiation alone. These studies show for the first time that FGF2 affects macrophage programming and is a critical regulator of immunity in the tumour microenvironment.


Asunto(s)
Factor 2 de Crecimiento de Fibroblastos/metabolismo , Radioterapia/métodos , Animales , Línea Celular Tumoral , Factor 2 de Crecimiento de Fibroblastos/genética , Células HT29 , Humanos , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Activación de Macrófagos/efectos de los fármacos , Activación de Macrófagos/efectos de la radiación , Receptor de Manosa , Lectinas de Unión a Manosa/genética , Lectinas de Unión a Manosa/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Desnudos , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/efectos de la radiación , Ensayos Antitumor por Modelo de Xenoinjerto
19.
Br J Hosp Med (Lond) ; 80(6): 343-347, 2019 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-31180764

RESUMEN

PURPOSE: Predicting perioperative morbidity and mortality can be achieved by several risk predicting algorithms. In the UK, the National Emergency Laparotomy Audit, mandated for all patients undergoing emergency laparotomy, uses pPOSSUM as its risk prediction tool. However, there is no literature reporting the inter-operator variability in calculating the score. Inter-rater variability was assessed based on 10 real general surgical cases that went on to have an emergency laparotomy. METHODS: Forty clinicians, 10 each of registrars and consultants in anaesthetics and general surgery, were asked to calculate the pPOSSUM based on the clinical information typically available at the time of making the decision to proceed to emergency laparotomy for the same 10 National Emergency Laparotomy Audit cases. All participants were surveyed to assess their understanding and use of the pPOSSUM score. RESULTS: More than 80% of respondents stated that they use pPOSSUM in daily clinical practice. There was variability in the calculated scores between the groups analysed. Two subgroups were evident: one in which the calculated mean pPOSSUM was similar between participants but did not reflect the true value, and the other which was accurate, but demonstrated high inter-rater variability. CONCLUSIONS: This is the first study to investigate inter-operator variability in pPOSSUM scores. Previous reports on the validity of the tool fail to account for subjective variation. At a time where pPOSSUM has become a routine part of clinical practice, this variability needs to be accounted for and taken into consideration in the decision-making process.


Asunto(s)
Mortalidad Hospitalaria/tendencias , Laparotomía/mortalidad , Periodo Perioperatorio/estadística & datos numéricos , Factores de Edad , Antitrombina III , Presión Sanguínea , Pruebas Diagnósticas de Rutina , Humanos , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Medición de Riesgo , Factores de Riesgo , Reino Unido
20.
J Healthc Qual ; 41(4): 243-250, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30648999

RESUMEN

Colorectal cancer (CRC) is the third most common cancer and the second leading cause of cancer-related death in the United States. Colonoscopy and fecal immunochemistry testing (FIT) are the primary recommended CRC screening modalities. The purpose of this study is to improve rates of CRC screening in Veterans and County hospital patients referred to gastroenterology fellow's clinics. A total of 717 patients between ages of 49 and 75 years were seen. Previous CRC screening was not performed in 109 patients (15.2%) because of not being offered (73.4%) or declining (26.6%) screening. Patients who received previous CRC screening compared with no previous screening were older (mean age 62.3 years vs. 60.3 years, p < .003), white (88.6% vs. 78.3%, p < .027), and more likely to be Veterans patients (90.8% vs. 77.5%, p < .001). After systematically discussing options for screening with 78 of the 109 unscreened patients, 56 of them (71.8%) underwent screening with either colonoscopy (32) or FIT (24). Patients seen by fellows in their last year of training agreed to undergo screening more often than those seen by other fellows (100% vs. 66.2%, p < .033). Systematic discussions about both colonoscopy and FIT can improve the overall rates of CRC screening.


Asunto(s)
Instituciones de Atención Ambulatoria/estadística & datos numéricos , Colonoscopía/estadística & datos numéricos , Neoplasias Colorrectales/diagnóstico , Detección Precoz del Cáncer/estadística & datos numéricos , Gastroenterología/estadística & datos numéricos , Tamizaje Masivo/estadística & datos numéricos , Servicios de Salud para Veteranos/estadística & datos numéricos , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estados Unidos
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