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1.
Nature ; 579(7797): 111-117, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32103177

RESUMO

The avascular nature of cartilage makes it a unique tissue1-4, but whether and how the absence of nutrient supply regulates chondrogenesis remain unknown. Here we show that obstruction of vascular invasion during bone healing favours chondrogenic over osteogenic differentiation of skeletal progenitor cells. Unexpectedly, this process is driven by a decreased availability of extracellular lipids. When lipids are scarce, skeletal progenitors activate forkhead box O (FOXO) transcription factors, which bind to the Sox9 promoter and increase its expression. Besides initiating chondrogenesis, SOX9 acts as a regulator of cellular metabolism by suppressing oxidation of fatty acids, and thus adapts the cells to an avascular life. Our results define lipid scarcity as an important determinant of chondrogenic commitment, reveal a role for FOXO transcription factors during lipid starvation, and identify SOX9 as a critical metabolic mediator. These data highlight the importance of the nutritional microenvironment in the specification of skeletal cell fate.


Assuntos
Osso e Ossos/citologia , Microambiente Celular , Condrogênese , Metabolismo dos Lipídeos , Fatores de Transcrição SOX9/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Animais , Osso e Ossos/irrigação sanguínea , Condrócitos/citologia , Condrócitos/metabolismo , Ácidos Graxos/metabolismo , Feminino , Privação de Alimentos , Fatores de Transcrição Forkhead/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Osteogênese , Oxirredução , Fatores de Transcrição SOX9/genética , Transdução de Sinais , Cicatrização
2.
Agric Econ ; 52(3): 365-374, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34149127

RESUMO

The food system, and those who depend on it, have been strongly but unevenly affected by COVID-19. Overall, the impacts on food systems, poverty, and nutrition have been caused by a combination of a generalized economic recession and disruptions in agri-food supply chains. This paper provides an overview of the contributions to this Special Issue of Agricultural Economics. The papers in this volume confirm that both income shocks and supply disruptions have affected food security and livelihoods the most where supply chains were more poorly integrated, and poverty and market informality had greater presence before COVID-19. Yet, as the pandemic still has societies worldwide in a stranglehold, outcomes remain uncertain and reliable data are still sparsely available. This Special Issue of Agricultural Economics provides new insights of the pandemics impact on food systems, household welfare, and food security, building on both model-based scenario analysis and new survey data. These methods have proven helpful in providing these insights amidst the unprecedented shock that the pandemic has caused to production systems and livelihoods worldwide. However, they also suffer from obvious limitations identified in this editorial overview paper and require substantial improvement in order to understand the changes in economic behavior and functioning of food supply chains induced by the pandemic.

3.
Int J Cancer ; 143(7): 1817-1828, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29707770

RESUMO

To better inform the next clinical trials of vascular disrupting agent combretastatin-A4-phosphate (CA4P) in patients with hepatic malignancies, this preclinical study aimed at evaluating CA4P therapeutic efficacy in rats with primary hepatocellular carcinomas (HCCs) of a full spectrum of differentiation and vascularity by magnetic resonance imaging (MRI), microangiography and histopathology. Ninety-six HCCs were raised in 25 rats by diethylnitrosamine gavage. Tumor growth was monitored by T2-/T1-weighted-MRI (T2WI, T1WI) using a 3.0 T scanner. Early vascular response and later intratumoral necrosis were detected by dynamic-contrast-enhanced (DCE) MRI and diffusion-weighted-imaging (DWI) before, 1 and 12 hr after CA4P iv-administration. In vivo MRI-findings were validated by postmortem-techniques. Multi-parametric MRI revealed rapid CA4P-induced tumor vascular shutdown within 1 hr, followed by variable intratumoral necrosis at 12 hr. Tumor volumes decreased by 10% at 1 hr (p < 0.05), but resumed at 12 hr. Correlations of semi-quantitative DCE parameter initial-area-under-the-gadolinium-curve (IAUGC30) with histopathology proved partial vascular closure and compensational reopening (p < 0.05). The higher grades of vascularity prevented those residual tumor tissues from CA4P-caused ischemic necrosis. By histopathology using a 4-scale cellular-differentiation criteria and a 4-grade tumor-vascularity classification, percentage of CA4P-induced necrosis negatively correlated with HCC differentiation (r = -0.404, p < 0.001) and tumor vascularity (r = -0.370, p < 0.001). Ordinal-logistic-regression helped to predict early tumor responses to CA4P in terms of tumoral differentiation and vascularity. Our study demonstrated that CA4P could induce vascular shutdown in primary HCCs within 1 hr, resulting in various degrees of tumor necrosis at 12 hr. MRI as a real-time imaging biomarker may help to define tumor vascularity and differentiation and further to predict CA4P therapeutic outcomes.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Imageamento por Ressonância Magnética/métodos , Neovascularização Patológica/prevenção & controle , Estilbenos/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/patologia , Meios de Contraste , Humanos , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Carga Tumoral , Células Tumorais Cultivadas
4.
BMC Cancer ; 18(1): 354, 2018 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-29606109

RESUMO

BACKGROUND: Recent retrospective data suggest that neoadjuvant androgen deprivation therapy can improve the prognosis of high-risk prostate cancer (PCa) patients. Novel androgen receptor pathway inhibitors are nowadays available for treatment of metastatic PCa and these compounds are promising for early stage disease. Apalutamide is a pure androgen antagonist with a very high affinity with the androgen receptor. The combination of apalutamide with degarelix, an LHRH antagonist, could increase the efficacy compared to degarelix alone. OBJECTIVE: The primary objective is to assess the difference in proportions of minimal residual disease at prostatectomy specimen between apalutamide + degarelix vs placebo + degarelix. Various secondary endpoints are assessed: variations of different biomarkers at the tumour level (tissue microarrays to evaluate DNA-PKs, PARP, AR and splice variants, PSMA, etc.), whole transcriptome sequencing, exome sequencing and clinical (PSA and testosterone kinetics, early biochemical recurrence free survival, quality of life, safety, etc.) and radiological endpoints. METHODS: ARNEO is a single centre, phase II, randomized, double blind, placebo-controlled trial. The plan is to include at least 42 patients per each of the two study arms. Patients with intermediate/high-risk PCa and who are amenable for radical prostatectomy with pelvic lymph node dissection can be included. After signing an informed consent, every patient will undergo a pelvic 68Ga -PSMA-11 PSMA PET/MR and receive degarelix at standard dosage and start assuming apalutamide/placebo (60 mg 4 tablets/day) for 12 weeks. Within thirty days from the last study medication intake the same imaging will be repeated. Every patient will undergo PSA and testosterone testing the day of randomization, before the first drug intake, and after the last dose. Formalin fixed paraffin embedded tumour samples will be collected and used for transcriptome analysis, exome sequencing and immunohistochemistry. DISCUSSION: ARNEO will allow us to answer, first, whether the combined treatment can result in an increased proportion of patients with minimal residual disease. Secondly, It will enable the study of the molecular consequences at the level of the tumour. Thirdly, what the consequences are of new generation androgen receptor pathway inhibitors on 68Ga -PSMA-11 PET/MR. Finally, various clinical, safety and quality of life data will be collected. TRIAL REGISTRATION: EUDRaCT number: 2016-002854-19 (authorization date 3rd August 2017). clinicalTrial.gov: NCT03080116 .


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos Clínicos , Oligopeptídeos/uso terapêutico , Prostatectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Antineoplásicos Hormonais/administração & dosagem , Antineoplásicos Hormonais/efeitos adversos , Antineoplásicos Hormonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ensaios Clínicos Fase II como Assunto , Humanos , Masculino , Terapia Neoadjuvante/métodos , Oligopeptídeos/administração & dosagem , Oligopeptídeos/efeitos adversos , Prostatectomia/métodos , Neoplasias da Próstata/mortalidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Tioidantoínas/administração & dosagem
6.
Commun Biol ; 7(1): 618, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783087

RESUMO

Endothelial cells (ECs) are highly glycolytic, but whether they generate glycolytic intermediates via gluconeogenesis (GNG) in glucose-deprived conditions remains unknown. Here, we report that glucose-deprived ECs upregulate the GNG enzyme PCK2 and rely on a PCK2-dependent truncated GNG, whereby lactate and glutamine are used for the synthesis of lower glycolytic intermediates that enter the serine and glycerophospholipid biosynthesis pathways, which can play key roles in redox homeostasis and phospholipid synthesis, respectively. Unexpectedly, however, even in normal glucose conditions, and independent of its enzymatic activity, PCK2 silencing perturbs proteostasis, beyond its traditional GNG role. Indeed, PCK2-silenced ECs have an impaired unfolded protein response, leading to accumulation of misfolded proteins, which due to defective proteasomes and impaired autophagy, results in the accumulation of protein aggregates in lysosomes and EC demise. Ultimately, loss of PCK2 in ECs impaired vessel sprouting. This study identifies a role for PCK2 in proteostasis beyond GNG.


Assuntos
Células Endoteliais , Gluconeogênese , Fosfoenolpiruvato Carboxiquinase (GTP) , Proteostase , Gluconeogênese/genética , Humanos , Células Endoteliais/metabolismo , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , Fosfoenolpiruvato Carboxiquinase (GTP)/genética , Células Endoteliais da Veia Umbilical Humana/metabolismo , Glucose/metabolismo , Autofagia , Resposta a Proteínas não Dobradas , Fosfoenolpiruvato Carboxiquinase (ATP)
7.
J Urol ; 189(5): 1930-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23206420

RESUMO

PURPOSE: We identified microRNA driven mechanisms in clear cell renal cell carcinoma associated with the tumor response to the multitargeted receptor tyrosine kinase inhibitor sunitinib. MATERIALS AND METHODS: We performed screening genome-wide microRNA real-time quantitative polymerase chain reaction on 20 freshly frozen clear cell renal cell carcinoma tissue samples of patients who received sunitinib as first line targeted therapy. Nine patients with progressive disease within 6 months after initiating therapy were considered poor responders and 11 with at least 1-year progression-free survival were considered good responders. We studied microRNA-141 function in vitro by stable up-regulation of microRNA-141, quantification of target gene expression and cell viability in normoxic and hypoxic conditions. Relative expression in clinical and cell line samples was determined by real-time quantitative polymerase chain reaction. Localization of microRNA-141 and its targets was assessed by microRNA in situ hybridization and immunohistochemistry. Hypoxia induced cytotoxicity was assessed by a luminescence adenosine triphosphate detection assay. RESULTS: Compared to good responders, microRNA-141 was significantly down-regulated in tumors of poor responders to sunitinib. This seemed spatially linked to epithelial-to-mesenchymal transition in vivo. Reintroduction of microRNA-141 in vitro reversed epithelial-to-mesenchymal transition and decreased cell viability in hypoxic conditions. CONCLUSIONS: In our study microRNA-141 down-regulation driven epithelial-to-mesenchymal transition in clear cell renal cell carcinoma was linked to an unfavorable response to sunitinib therapy. Reintroduction of microRNA-141 in vitro led to epithelial-to-mesenchymal transition reversal and increased sensibility to a hypoxic environment. Future experiments should be done in vivo to see whether microRNA-141 driven reversal of epithelial-to-mesenchymal transition could affect the efficacy of sunitinib treatment.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/genética , Hipóxia Celular/genética , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/genética , Transição Epitelial-Mesenquimal/genética , Indóis/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , MicroRNAs/fisiologia , Pirróis/uso terapêutico , Humanos , Sunitinibe , Células Tumorais Cultivadas
8.
Acta Neuropathol Commun ; 11(1): 11, 2023 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-36641470

RESUMO

Automatic segmentation of rodent brain tumor on magnetic resonance imaging (MRI) may facilitate biomedical research. The current study aims to prove the feasibility for automatic segmentation by artificial intelligence (AI), and practicability of AI-assisted segmentation. MRI images, including T2WI, T1WI and CE-T1WI, of brain tumor from 57 WAG/Rij rats in KU Leuven and 46 mice from the cancer imaging archive (TCIA) were collected. A 3D U-Net architecture was adopted for segmentation of tumor bearing brain and brain tumor. After training, these models were tested with both datasets after Gaussian noise addition. Reduction of inter-observer disparity by AI-assisted segmentation was also evaluated. The AI model segmented tumor-bearing brain well for both Leuven and TCIA datasets, with Dice similarity coefficients (DSCs) of 0.87 and 0.85 respectively. After noise addition, the performance remained unchanged when the signal-noise ratio (SNR) was higher than two or eight, respectively. For the segmentation of tumor lesions, AI-based model yielded DSCs of 0.70 and 0.61 for Leuven and TCIA datasets respectively. Similarly, the performance is uncompromised when the SNR was over two and eight respectively. AI-assisted segmentation could significantly reduce the inter-observer disparities and segmentation time in both rats and mice. Both AI models for segmenting brain or tumor lesions could improve inter-observer agreement and therefore contributed to the standardization of the following biomedical studies.


Assuntos
Inteligência Artificial , Neoplasias Encefálicas , Ratos , Camundongos , Animais , Processamento de Imagem Assistida por Computador/métodos , Roedores , Imageamento por Ressonância Magnética/métodos , Neoplasias Encefálicas/diagnóstico por imagem
9.
Mol Syst Biol ; 7: 541, 2011 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-22027552

RESUMO

We manufactured a novel type of lipid-coated superparamagnetic nanoparticles that allow for a rapid isolation of plasma membranes (PMs), enabling high-resolution proteomic, glycomic and lipidomic analyses of the cell surface. We used this technology to characterize the effects of presenilin knockout on the PM composition of mouse embryonic fibroblasts. We found that many proteins are selectively downregulated at the cell surface of presenilin knockout cells concomitant with lowered surface levels of cholesterol and certain sphingomyelin species, indicating defects in specific endosomal transport routes to and/or from the cell surface. Snapshots of N-glycoproteomics and cell surface glycan profiling further underscored the power and versatility of this novel methodology. Since PM proteins provide many pathologically relevant biomarkers representing two-thirds of the currently used drug targets, this novel technology has great potential for biomedical and pharmaceutical applications.


Assuntos
Membrana Celular/química , Nanopartículas de Magnetita , Proteínas de Membrana/análise , Presenilinas/genética , Proteômica/métodos , Animais , Linhagem Celular , Membrana Celular/metabolismo , Colesterol/análise , Colesterol/metabolismo , Endossomos/genética , Endossomos/patologia , Fibroblastos , Perfilação da Expressão Gênica , Técnicas de Inativação de Genes , Lipídeos de Membrana/análise , Lipídeos de Membrana/metabolismo , Proteínas de Membrana/genética , Camundongos , Esfingomielinas/análise , Esfingomielinas/metabolismo
10.
Cancers (Basel) ; 14(7)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35406378

RESUMO

The epidemiology and associated potential heterogeneity of synchronous lung metastasis (sLM) have not been reported at a population-based level. Cancer patients with valid information about sLM status in the Surveillance, Epidemiology, and End Results database were enrolled. The prevalence of sLM, with a 95% confidential interval, and median survival of sLM, with interquartile range, were calculated and compared by Chi-square analyses and log-rank tests by primary cancer type and clinicopathological factors. Furthermore, the risk factors of sLM development were identified by multivariate logistic regression. Among 1,672,265 enrolled cases, 3.3% cases were identified with sLM, with a median survival of 7 months. Heterogeneity in prevalence and prognosis in sLM was observed among different primary cancers, with the highest prevalence in main bronchus cancer and best survival in testis cancer. Higher prevalence and poorer prognosis were observed in the older population, male population, African American, patients with lower socioeconomic status, and cases with advanced T stage, N stage, or more malignant pathological characteristics. Race, age, T stage, N stage, metastasis to other sites, insurance status and marital status were associated with sLM development (p < 0.001). The current study highlights the heterogeneity of the prevalence and prognosis in patients with sLM.

11.
Clin Exp Metastasis ; 39(3): 479-493, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35218457

RESUMO

To facilitate the development of new brain metastasis (BM) treatment, an easy-to-use and clinically relevant animal model with imaging platform is needed. Rhabdomyosarcoma BM was induced in WAG/Rij rats. Post-implantation surveillance and characterizations were systematically performed with multiparametric MRI including 3D T1 and T2 weighted imaging, diffusion-weighted imaging (DWI), T1 and T2 mapping, and perfusion-weighted imaging (PWI), which were validated by postmortem digital radiography (DR), µCT angiography and histopathology. The translational potential was exemplified by the application of a vascular disrupting agent (VDA). BM was successfully induced in most rats of both genders (18/20). Multiparametric MRI revealed significantly higher T2 value, pre-contrast-enhanced (preCE) T1 value, DWI-derived apparent diffusion coefficient (ADC) and CE ratio, but a lower post-contrast-enhanced (postCE) T1 value in BM lesions than in adjacent brain (p < 0.01). PWI showed the dynamic and higher contrast agent uptake in the BM compared with the adjacent brain. DR, µCT and histopathology characterized the BM as hypervascular tumors. After VDA treatment, the BM showed drug-related perfusion changes and partial necrosis as evidenced by anatomical, functional MRI parameters and postmortem findings. The present BM model and imaging modalities represent a feasible and translational platform for developing BM-targeting therapeutics.


Assuntos
Neoplasias Encefálicas , Imageamento por Ressonância Magnética Multiparamétrica , Animais , Encéfalo , Neoplasias Encefálicas/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Ratos
12.
Front Immunol ; 13: 1003975, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36531986

RESUMO

Junctional adhesion molecule-A (JAM-A), expressed on the surface of myeloid cells, is required for extravasation at sites of inflammation and may also modulate myeloid cell activation. Infiltration of myeloid cells is a common feature of tumors that drives disease progression, but the function of JAM-A in this phenomenon and its impact on tumor-infiltrating myeloid cells is little understood. Here we show that systemic cancer-associated inflammation in mice enhanced JAM-A expression selectively on circulating monocytes in an IL1ß-dependent manner. Using myeloid-specific JAM-A-deficient mice, we found that JAM-A was dispensable for recruitment of monocytes and other myeloid cells to tumors, in contrast to its reported role in inflammation. Single-cell RNA sequencing revealed that loss of JAM-A did not influence the transcriptional reprogramming of myeloid cells in the tumor microenvironment. Overall, our results support the notion that cancer-associated inflammation can modulate the phenotype of circulating immune cells, and we demonstrate that tumors can bypass the requirement of JAM-A for myeloid cell recruitment and reprogramming.


Assuntos
Molécula A de Adesão Juncional , Camundongos , Animais , Microambiente Tumoral/genética , Células Mieloides/metabolismo , Monócitos/metabolismo , Inflamação/metabolismo
13.
Nat Commun ; 13(1): 2760, 2022 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-35589749

RESUMO

Autophagy has vasculoprotective roles, but whether and how it regulates lymphatic endothelial cells (LEC) homeostasis and lymphangiogenesis is unknown. Here, we show that genetic deficiency of autophagy in LEC impairs responses to VEGF-C and injury-driven corneal lymphangiogenesis. Autophagy loss in LEC compromises the expression of main effectors of LEC identity, like VEGFR3, affects mitochondrial dynamics and causes an accumulation of lipid droplets (LDs) in vitro and in vivo. When lipophagy is impaired, mitochondrial ATP production, fatty acid oxidation, acetyl-CoA/CoA ratio and expression of lymphangiogenic PROX1 target genes are dwindled. Enforcing mitochondria fusion by silencing dynamin-related-protein 1 (DRP1) in autophagy-deficient LEC fails to restore LDs turnover and lymphatic gene expression, whereas supplementing the fatty acid precursor acetate rescues VEGFR3 levels and signaling, and lymphangiogenesis in LEC-Atg5-/- mice. Our findings reveal that lipophagy in LEC by supporting FAO, preserves a mitochondrial-PROX1 gene expression circuit that safeguards LEC responsiveness to lymphangiogenic mediators and lymphangiogenesis.


Assuntos
Linfangiogênese , Vasos Linfáticos , Animais , Autofagia/genética , Células Endoteliais/metabolismo , Ácidos Graxos/metabolismo , Gotículas Lipídicas/metabolismo , Linfangiogênese/genética , Vasos Linfáticos/metabolismo , Camundongos , Mitocôndrias , Fatores de Transcrição/metabolismo
14.
Nutrients ; 13(10)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34684461

RESUMO

(1) Background: Obesity and type 2 diabetes have been suspected to impact both intrinsic metabolism and function of circulating immune cells. (2) Methods: To further investigate this immunometabolic modulation, we profiled the phospholipidome of the peripheral blood mononuclear cells (PBMCs) in lean, normoglycemic obese (OBNG) and obese with dysglycemia (OBDysG) individuals. (3) Results: The global PBMCs phospholipidome is significantly downmodulated in OBDysG unlike OBNG patients when compared to lean ones. Multiple linear regression analyses show a strong negative relationship between the global PBMCs phospholipidome and parameters assessing insulin resistance. Even though all classes of phospholipid are affected, the relative abundance of each class is maintained with the exception of Lyso-PC/PC and Lyso-PE/PE ratios that are downmodulated in PBMCs of OBDysG compared to OBNG individuals. Interestingly, the percentage of saturated PC is positively associated with glycated hemoglobin (HbA1c). Moreover, a few lipid species are significantly downmodulated in PBMCs of OBDysG compared to OBNG individuals, making possible to distinguish the two phenotypes. (4) Conclusions: This lipidomic study highlights for the first-time modulations of the PBMCs phospholipidome in obese patients with prediabetes and type 2 diabetes. Such phospholipidome remodeling could disrupt the cell membranes and the lipid mediator's levels, driving an immune cell dysfunction.


Assuntos
Glicemia , Resistência à Insulina , Leucócitos Mononucleares/metabolismo , Lipidômica , Obesidade/metabolismo , Fosfolipídeos/metabolismo , Adulto , Biomarcadores , Pesos e Medidas Corporais , Biologia Computacional , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Lipidômica/métodos , Masculino , Espectrometria de Massas , Lipídeos de Membrana , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/etiologia , Adulto Jovem
15.
Am J Cancer Res ; 10(5): 1477-1517, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32509393

RESUMO

Metastasis is a major cause of cancer-related death and liver metastasis (LM) is a distinct type for its relatively good prognosis after timely treatment for selected patients. However, a generalizable estimation of incidence and prognosis of LM is lacking. Cancer patients with known LM status in the Surveillance, Epidemiology and End Results database were enrolled in the present study. The incidence and prognosis of LM were calculated by primary cancer type and clinicopathological factors. Among 1,630,725 cases, 105,329 (6.46%) cases present LM at diagnosis, with a median survival of 4 months. LM presents at diagnosis in 39.96% of pancreatic cancer, 16.00% of colorectal cancer (CRC) and 12.68% of lung cancer. Of all LM cases, 25.58% originated from lung cancer, with 24.76% from CRC and 17.55% from pancreatic cancer. LM originated from small intestine cancer shows the best prognosis (median survival: 30 months), followed by testis cancer (25 months) and breast cancer (15 months). Subgroup analyses demonstrated disparities in incidence and prognosis of LM, with higher incidence and poorer prognosis in the older population, African American, male, and patients with inferior socioeconomic status. The current study provides a generalizable data resource for the epidemiology of LM, which may help tailor screening protocol, design clinical trials and estimate disease burden.

16.
Diagnostics (Basel) ; 10(2)2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32024029

RESUMO

Vascular disrupting agents (VDAs) have entered clinical trials for over 15 years. As the leading VDA, combretastatin A4 phosphate (CA4P) has been evaluated in combination with chemotherapy and molecular targeting agents among patients with ovarian cancer, lung cancer and thyroid cancer, but still remains rarely explored in human liver cancers. To overcome tumor residues and regrowth after CA4P monotherapy, a novel dual targeting pan-anticancer theragnostic strategy, i.e., OncoCiDia, has been developed and shown promise previously in secondary liver tumor models. Animal model of primary liver cancer is time consuming to induce, but of value for more closely mimicking human liver cancers in terms of tumor angiogenesis, histopathological heterogeneity, cellular differentiation, tumor components, cancer progression and therapeutic response. Being increasingly adopted in VDA researches, multiparametric magnetic resonance imaging (MRI) provides imaging biomarkers to reflect in vivo tumor responses to drugs. In this article as a chapter of a doctoral thesis, we overview the construction and clinical relevance of primary and secondary liver cancer models in rodents. Target selection for CA4P therapy assisted by enhanced MRI using hepatobiliary contrast agents (CAs), and therapeutic efficacy evaluated by using MRI with a non-specific contrast agent, dynamic contrast enhanced (DCE) imaging, diffusion weighted imaging (DWI) are also described. We then summarize diverse responses among primary hepatocellular carcinomas (HCCs), secondary liver and pancreatic tumors to CA4P, which appeared to be related to tumor size, vascularity, and cellular differentiation. In general, imaging-histopathology correlation studies allow to conclude that CA4P tends to be more effective in secondary liver tumors and in more differentiated HCCs, but less effective in less differentiated HCCs and implanted pancreatic tumor. Notably, cirrhotic liver may be responsive to CA4P as well. All these could be instructive for future clinical trials of VDAs.

17.
Cancer Metab ; 8: 11, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32577235

RESUMO

BACKGROUND: Metabolic reprograming, non-mutational epigenetic changes, increased cell plasticity, and multidrug tolerance are early hallmarks of therapy resistance in cancer. In this temporary, therapy-tolerant state, cancer cells are highly sensitive to ferroptosis, a form of regulated cell death that is caused by oxidative stress through excess levels of iron-dependent peroxidation of polyunsaturated fatty acids (PUFA). However, mechanisms underpinning therapy-induced ferroptosis hypersensitivity remain to be elucidated. METHODS: We used quantitative single-cell imaging of fluorescent metabolic probes, transcriptomics, proteomics, and lipidomics to perform a longitudinal analysis of the adaptive response to androgen receptor-targeted therapies (androgen deprivation and enzalutamide) in prostate cancer (PCa). RESULTS: We discovered that cessation of cell proliferation and a robust reduction in bioenergetic processes were associated with multidrug tolerance and a strong accumulation of lipids. The gain in lipid biomass was fueled by enhanced lipid uptake through cargo non-selective (macropinocytosis, tunneling nanotubes) and cargo-selective mechanisms (lipid transporters), whereas de novo lipid synthesis was strongly reduced. Enzalutamide induced extensive lipid remodeling of all major phospholipid classes at the expense of storage lipids, leading to increased desaturation and acyl chain length of membrane lipids. The rise in membrane PUFA levels enhanced membrane fluidity and lipid peroxidation, causing hypersensitivity to glutathione peroxidase (GPX4) inhibition and ferroptosis. Combination treatments against AR and fatty acid desaturation, lipase activities, or growth medium supplementation with antioxidants or PUFAs altered GPX4 dependence. CONCLUSIONS: Our work provides mechanistic insight into processes of lipid metabolism that underpin the acquisition of therapy-induced GPX4 dependence and ferroptosis hypersensitivity to standard of care therapies in PCa. It demonstrates novel strategies to suppress the therapy-tolerant state that may have potential to delay and combat resistance to androgen receptor-targeted therapies, a currently unmet clinical challenge of advanced PCa. Since enhanced GPX4 dependence is an adaptive phenotype shared by several types of cancer in response to different therapies, our work might have universal implications for our understanding of metabolic events that underpin resistance to cancer therapies.

18.
Transl Oncol ; 13(1): 92-101, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31810003

RESUMO

To evaluate hepatobiliary-specific contrast agent (CA) mangafodipir trisodium (Mn-DPDP)-enhanced magnetic resonance imaging (MRI) for predicting the therapeutic efficacy of the vascular disrupting agent combretastatin A4 phosphate (CA4P) in rats with primary and secondary liver tumors, 36 primary hepatocellular carcinomas (HCCs) were raised by diethylnitrosamine gavage in 16 male rats, in 6 of which one rhabdomyosarcomas (R1) was intrahepatically implanted as secondary liver tumors. On a 3.0T MR scanner with a wrist coil, tumors were monitored weekly by T2-/T1-weighted images (T2WI/T1WI) and characterized by Mn-DPDP-enhanced MRI. CA4P-induced intratumoral necrosis was depicted by nonspecific gadoterate meglumine (Gd-DOTA)-enhanced MRI before and 12 h after therapy. Changes of tumor-to-liver contrast (ΔT/L) on Mn-DPDP-enhanced images were analyzed. In vivo MRI findings were verified by postmortem microangiography and histopathology. Rat models of primary HCCs in a full spectrum of differentiation and secondary R1 liver tumors were successfully generated. Mn-DPDP-enhanced ΔT/L was negatively correlated with HCC differentiation grade (P < 0.01). After treatment with CA4P, more extensive tumoral necrosis was found in highly differentiated HCCs than that in moderately and poorly differentiated ones (P < 0.01); nearly complete necrosis was induced in secondary liver tumors. Mn-DPDP-enhanced MRI may help in imaging diagnosis of primary and secondary liver malignancies of different cellular differentiations and further in predicting CA4P therapeutic efficacy in primary HCCs and intrahepatic metastases.

20.
Cancers (Basel) ; 11(11)2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31766180

RESUMO

Cancer remains a major cause of death globally. Given its relapsing and fatal features, curing cancer seems to be something hardly possible for the majority of patients. In view of the development in cancer therapies, this article summarizes currently available cancer therapeutics and cure potential by cancer type and stage at diagnosis, based on literature and database reviews. Currently common cancer therapeutics include surgery, chemotherapy, radiotherapy, targeted therapy, and immunotherapy. However, treatment with curative intent by these methods are mainly eligible for patients with localized disease or treatment-sensitive cancers and therefore their contributions to cancer curability are relatively limited. The prognosis for cancer patients varies among different cancer types with a five-year relative survival rate (RSR) of more than 80% in thyroid cancer, melanoma, breast cancer, and Hodgkin's lymphoma. The most dismal prognosis is observed in patients with small-cell lung cancer, pancreatic cancer, hepatocellular carcinoma, oesophagal cancer, acute myeloid leukemia, non-small cell lung cancer, and gastric cancer with a five-year RSR ranging between 7% and 28%. The current review is intended to provide a general view about how much we have achieved in curing cancer as regards to different therapies and cancer types. Finally, we propose a small molecule dual-targeting broad-spectrum anticancer strategy called OncoCiDia, in combination with emerging highly sensitive liquid biopsy, with theoretical curative potential for the management of solid malignancies, especially at the micro-cancer stage.

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