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1.
Am J Cancer Res ; 13(12): 6290-6312, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38187068

RESUMO

Gastric adenocarcinoma typically presents with advanced stage when inoperable. Chemotherapy options include non-targeted and toxic agents, leading to poor 5-year patient survival outcomes. Small molecule ONC201/TIC10 (TRAIL-Inducing Compound #10) induces cancer cell death via ClpP-dependent activation of the integrated stress response (ISR) and up-regulation of the TRAIL pathway. We previously found in breast cancer, pancreatic cancer and endometrial cancer that ONC201 primes tumor cells for TRAIL-mediated cell death through ISR-dependent upregulation of ATF4, CHOP and TRAIL death receptor DR5. We investigated the ability of ONC201 to induce apoptosis in gastric adenocarcinoma cells in combination with recombinant human TRAIL (rhTRAIL) or PEGylated trimeric TRAIL (TLY012). AGS (caspase 8-, KRAS-, PIK3CA-mutant, HER2-amplified), SNU-1 (KRAS-, MLH1-mutant, microsatellite unstable), SNU-5 (p53-mutant) and SNU-16 (p53-mutant) gastric adenocarcinoma cells were treated with ONC201 and TRAIL both in cell culture and in vivo. Gastric cancer cells showed synergy following dual therapy with ONC201 and rhTRAIL/TLY012 (combination indices < 0.6 at doses that were non-toxic towards normal fibroblasts). Synergy was observed with increased cells in the sub-G1 phase of the cell cycle with dual ONC201 plus TRAIL therapy. Increased PARP, caspase 8 and caspase 3 cleavage after ONC201 plus TRAIL further documented apoptosis. Increased cell surface expression of DR5 with ONC201 therapy was observed by flow cytometry, and immunoblotting revealed ONC201 upregulation of the ISR, ATF4, and CHOP. We observed downregulation of anti-apoptotic cIAP-1 and XIAP in all cells except AGS, and cFLIP in all cells except SNU-16. We tested the regimen in an organoid model of human gastric cancer, and in murine sub-cutaneous xenografts using AGS and SNU-1 cells. Our results suggest that ONC201 in combination with TRAIL may be an effective and non-toxic option for the treatment of gastric adenocarcinoma by inducing apoptosis via activation of the ISR, increased cell surface expression of DR5 and down-regulation of inhibitors of apoptosis. Our results demonstrate in vivo anti-tumor effects of ONC201 plus TLY012 against gastric cancer that could be further investigated in clinical trials.

2.
Front Pharmacol ; 12: 751568, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34916936

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease characterized by early metastasis, late detection, and poor prognosis. Progress towards effective therapy has been slow despite significant efforts. Novel treatment approaches are desperately needed and autophagy, an evolutionary conserved process through which proteins and organelles are recycled for use as alternative energy sources, may represent one such target. Although incompletely understood, there is growing evidence suggesting that autophagy may play a role in PDAC carcinogenesis, metastasis, and survival. Early clinical trials involving autophagy inhibiting agents, either alone or in combination with chemotherapy, have been disappointing. Recently, evidence has demonstrated synergy between the MAPK pathway and autophagy inhibitors in PDAC, suggesting a promising therapeutic intervention. In addition, novel agents, such as ONC212, have preclinical activity in pancreatic cancer, in part through autophagy inhibition. We discuss autophagy in PDAC tumorigenesis, metabolism, modulation of the immune response, and preclinical and clinical data with selected autophagy modulators as therapeutics.

3.
Surg Oncol Clin N Am ; 30(3): 449-459, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34053661

RESUMO

Surgical palliation in oncology can be defined as "procedures employed with non-curative intent with the primary goal of improving symptoms caused by an advanced malignancy," and is an important aspect of the end-of-life care of patients with incurable malignancies. Palliative interventions may provide great benefit, but they also carry high risk for morbidity and mortality, which may be minimized with careful patient selection. This can be done by consideration of the patient and his or her indication for the given intervention via open communication, as well as prediction of benefits and risks to define the therapeutic index of the operation or procedure.


Assuntos
Neoplasias , Qualidade de Vida , Feminino , Humanos , Masculino , Morbidade , Neoplasias/terapia , Cuidados Paliativos , Seleção de Pacientes
4.
Oncotarget ; 11(46): 4201-4223, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33245731

RESUMO

COVID-19 affects vulnerable populations including elderly individuals and patients with cancer. Natural Killer (NK) cells and innate-immune TRAIL suppress transformed and virally-infected cells. ACE2, and TMPRSS2 protease promote SARS-CoV-2 infectivity, while inflammatory cytokines IL-6, or G-CSF worsen COVID-19 severity. We show MEK inhibitors (MEKi) VS-6766, trametinib and selumetinib reduce ACE2 expression in human cells. In some human cells, remdesivir increases ACE2-promoter luciferase-reporter expression, ACE2 mRNA and protein, and ACE2 expression is attenuated by MEKi. In serum-deprived and stimulated cells treated with remdesivir and MEKi we observed correlations between pRB, pERK, and ACE2 expression further supporting role of proliferative state and MAPK pathway in ACE2 regulation. We show elevated cytokines in COVID-19-(+) patient plasma (N = 9) versus control (N = 11). TMPRSS2, inflammatory cytokines G-CSF, M-CSF, IL-1α, IL-6 and MCP-1 are suppressed by MEKi alone or with remdesivir. We observed MEKi stimulation of NK-cell killing of target-cells, without suppressing TRAIL-mediated cytotoxicity. Pseudotyped SARS-CoV-2 virus with a lentiviral core and SARS-CoV-2 D614 or G614 SPIKE (S) protein on its envelope infected human bronchial epithelial cells, small airway epithelial cells, or lung cancer cells and MEKi suppressed infectivity of the pseudovirus. We show a drug class-effect with MEKi to stimulate NK cells, inhibit inflammatory cytokines and block host-factors for SARS-CoV-2 infection leading also to suppression of SARS-CoV-2-S pseudovirus infection of human cells. MEKi may attenuate SARS-CoV-2 infection to allow immune responses and antiviral agents to control disease progression.

5.
Neoplasia ; 22(12): 725-744, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33142238

RESUMO

ONC201 was originally discovered as TNF-Related Apoptosis Inducing Ligand (TRAIL)-inducing compound TIC10. ONC201 appears to act as a selective antagonist of the G protein coupled receptor (GPCR) dopamine receptor D2 (DRD2), and as an allosteric agonist of mitochondrial protease caseinolytic protease P (ClpP). Downstream of target engagement, ONC201 activates the ATF4/CHOP-mediated integrated stress response leading to TRAIL/Death Receptor 5 (DR5) activation, inhibits oxidative phosphorylation via c-myc, and inactivates Akt/ERK signaling in tumor cells. This typically results in DR5/TRAIL-mediated apoptosis of tumor cells; however, DR5/TRAIL-independent apoptosis, cell cycle arrest, or antiproliferative effects also occur. The effects of ONC201 extend beyond bulk tumor cells to include cancer stem cells, cancer associated fibroblasts and immune cells within the tumor microenvironment that can contribute to its efficacy. ONC201 is orally administered, crosses the intact blood brain barrier, and is under evaluation in clinical trials in patients with advanced solid tumors and hematological malignancies. ONC201 has single agent clinical activity in tumor types that are enriched for DRD2 and/or ClpP expression including specific subtypes of high-grade glioma, endometrial cancer, prostate cancer, mantle cell lymphoma, and adrenal tumors. Synergy with radiation, chemotherapy, targeted therapy and immune-checkpoint agents has been identified in preclinical models and is being evaluated in clinical trials. Structure-activity relationships based on the core pharmacophore of ONC201, termed the imipridone scaffold, revealed novel potent compounds that are being developed. Imipridones represent a novel approach to therapeutically target previously undruggable GPCRs, ClpP, and innate immune pathways in oncology.


Assuntos
Antineoplásicos/farmacologia , Imidazóis/farmacologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Animais , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos Clínicos como Assunto , Ensaios Clínicos como Assunto , Suscetibilidade a Doenças , Avaliação Pré-Clínica de Medicamentos , Endopeptidase Clp/genética , Endopeptidase Clp/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imidazóis/uso terapêutico , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/etiologia , Neoplasias/metabolismo , Neoplasias/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Piridinas/uso terapêutico , Pirimidinas/uso terapêutico , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ligante Indutor de Apoptose Relacionado a TNF/agonistas , Resultado do Tratamento
6.
bioRxiv ; 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32793908

RESUMO

COVID-19 affects vulnerable populations including elderly individuals and patients with cancer. Natural Killer (NK) cells and innate-immune TRAIL suppress transformed and virally-infected cells. ACE2, and TMPRSS2 protease promote SARS-CoV-2 infectivity, while inflammatory cytokines IL-6, or G-CSF worsen COVID-19 severity. We show MEK inhibitors (MEKi) VS-6766, trametinib and selumetinib reduce ACE2 expression in human cells. In some human cells, remdesivir increases ACE2-promoter luciferase-reporter expression, ACE2 mRNA and protein, and ACE2 expression is attenuated by MEKi. In serum-deprived and stimulated cells treated with remdesivir and MEKi we observed correlations between pRB, pERK, and ACE2 expression further supporting role of proliferative state and MAPK pathway in ACE2 regulation. We show elevated cytokines in COVID-19-(+) patient plasma (N=9) versus control (N=11). TMPRSS2, inflammatory cytokines G-CSF, M-CSF, IL-1α, IL-6 and MCP-1 are suppressed by MEKi alone or with remdesivir. We observed MEKi stimulation of NK-cell killing of target-cells, without suppressing TRAIL-mediated cytotoxicity. Pseudotyped SARS-CoV-2 virus with a lentiviral core and SARS-CoV-2 D614 or G614 SPIKE (S) protein on its envelope infected human bronchial epithelial cells, small airway epithelial cells, or lung cancer cells and MEKi suppressed infectivity of the pseudovirus. We show a drug class-effect with MEKi to stimulate NK cells, inhibit inflammatory cytokines and block host-factors for SARS-CoV-2 infection leading also to suppression of SARS-CoV-2-S pseudovirus infection of human cells. MEKi may attenuate SARS-CoV-2 infection to allow immune responses and antiviral agents to control disease progression.

7.
Conserv Physiol ; 7(1): coz073, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31737272

RESUMO

In a changing climate, southern hemisphere mammals are predicted to face rising temperatures and aridity, resulting in food and water shortages, which may further challenge already constrained energetic demands. Especially semelparous mammals may be threatened because survival of the entire population depends on the success of a single breeding event. One of these species, the yellow-footed antechinus, Antechinus flavipes, a small, heterothermic marsupial mammal, commences reproduction during winter, when insect prey is limited and energetic constraints are high. We examined the inter-relations between thermal and foraging biology of free-ranging A. flavipes and examined whether they use torpor for energy conservation, despite the fact that reproduction and torpor are considered to be incompatible for many mammals. Females used torpor during the reproductive season, but patterns changed with reproductive status. Prior to breeding, females used frequent (86% of days), deep and long torpor that was more pronounced than any other reproductive group, including pre-mating males (64% of days). Pregnant females continued to use torpor, albeit torpor was less frequent (28% of days) and significantly shorter and shallower than before breeding. Parturient and lactating females did not express torpor. During the mating period, males reduced torpor use (24% of days). Pre-reproductive females and pre-mating males were the least active and may use torpor to minimize predator exposure and enhance fat deposition in anticipation of the energetic demands associated with impending mating, gestation and lactation. Reproductive females were most active and likely foraged and fed to promote growth and development of young. Our data show that A. flavipes are balancing energetic demands during the reproductive season by modifying torpor and activity patterns. As the timing of reproduction is fixed for this genus, it is probable that climate change will render these behavioural and physiological adaptations as inadequate and threaten this and other semelparous species.

8.
J Thorac Dis ; 10(Suppl 28): S3392-S3397, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30505526

RESUMO

The diagnosis of lung cancer can be delayed in patients with a history of infection with pulmonary tuberculosis that present with new lesions on chest imaging, due to a high initial index of suspicion for mycobacterium tuberculosis complex rather than malignancy. This may lead to diagnosis of malignancy at a more advanced stage of the disease with subsequent increased morbidity and mortality. We reviewed the current literature to evaluate various methods of differentiating between a diagnosis of lung cancer and tuberculosis including radiography, computerized tomography (CT), positron emission tomography (PET) and various biological markers. We included only papers published in English. Based on current data, we recommend that patients established as high risk, according to the American Association of Thoracic Surgery, patients with age greater than or equal to 55 years and a smoking history of greater than or equal to 30 pack years, should be assessed with CT for underlying malignancy prior to beginning tuberculosis treatment, even in the presence of a clinical or microbiologic diagnosis of tuberculosis. In patients with equivocal CT findings, we recommend examination of tumor markers miR128, miR210, miR126 along with CEA, if these tests are at the clinician's disposal.

9.
J Comp Physiol B ; 187(2): 385-393, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27734149

RESUMO

Wildfires can completely obliterate above-ground vegetation, yet some small terrestrial mammals survive during and after fires. As knowledge about the physiological and behavioural adaptations that are crucial for post-wildfire survival is scant, we investigated the thermal biology of a small insectivorous marsupial (Antechinus flavipes) after a severe forest fire. Some populations of antechinus survived the fire in situ probably by hiding deep in rocky crevices, the only fire-proof sites near where they were trapped. We hypothesised that survival in the post-fire landscape was achieved by decreasing daytime activity and using torpor frequently to save energy. Indeed, daytime activity was less common and torpor expression was substantially higher (≥2-fold) at the post-fire site than observed in an unburnt control site and also in comparison to a laboratory study, both when food was provided ad libitum and withheld. Basking in the post-fire site was also recorded, which was likely used to further reduce energy expenditure. Our data suggest that torpor and basking are used by this terrestrial mammal to reduce energy and foraging requirements, which is important in a landscape where food and shelter are limited and predation pressure typically is increased.


Assuntos
Comportamento Animal , Torpor/fisiologia , Incêndios Florestais , Animais , Metabolismo Energético , Feminino , Masculino , Marsupiais/fisiologia , Temperatura
10.
BMC Nephrol ; 17: 93, 2016 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-27456863

RESUMO

BACKGROUND: A lack of advanced healthcare information systems and validated scientific cohorts in Nicaragua makes it difficult to estimate disease prevalences and other public health statistics. Although there is concern of an "epidemic" of chronic kidney disease (CKD) in this country, statistics regarding its magnitude are derived from only a small number of non-representative studies. Budgetary constraints and the logistical problems of maintaining a study cohort make longitudinal studies difficult. The Rivas Cohort was created to measure disease burden of CKD and other public health priorities in the Department of Rivas, Nicaragua. Using primarily volunteer research students and technologic innovation including GPS, digital photography and point of care biochemical analysis, the ability to establish a longitudinal chronic disease cohort is demonstrated. METHODS: Subjects were recruited from consecutive adjacent households in thirty-two randomly selected communities in the ten municipalities that comprise the Department of Rivas in southern Pacific coastal Nicaragua. The study was conducted in two phases. In the first phase, subjects were enrolled into the cohort and consented for future re-contact. In Phase II, conducted two years later, attempts were made to re-contact 400 of these subjects for additional data collection. Demographic, lifestyle, occupational, exposure and health data was collected for both phases of the study. Blood and urine testing and height, weight and blood pressure measurements were also performed. GPS coordinates of homes were recorded and maps of remote communities created. RESULTS: Of 1397 adults living in 533 households approached for participation a total of 1242 (89 %) were enrolled in the cohort. The median age is 41 years and 43 % are male, demographics in agreement with Nicaraguan census data for the Department of Rivas. During Phase II we attempted to re-contact 400 subjects for a follow-up study of CKD. It was possible to re-contact 84 % of these participants and of those re-contacted 95 % agreed to participate in the follow-up study. Of subjects that were not successfully re-contacted the majority had either moved (32) or were not at home (22) at the time of the study team visits. CONCLUSION: The Rivas Cohort Study enrolled a representative sample of 1242 adults living in the Department of Rivas, Nicaragua. The high re-contact and participation rates at two years suggests that the cohort is suitable for long-term studies and presents opportunities for investigations of disease prevalence, incidence, treatment and other public health matters. GPS coordinates and maps are available for future researchers who wish to use the cohort for additional studies.


Assuntos
Insuficiência Renal/epidemiologia , Adulto , Estudos de Coortes , Creatinina/sangue , Demografia , Feminino , Seguimentos , Sistemas de Informação Geográfica , Humanos , Estudos Longitudinais , Masculino , Nicarágua/epidemiologia , Sistemas Automatizados de Assistência Junto ao Leito , Prevalência , Insuficiência Renal/diagnóstico , Urinálise
11.
Behav Brain Res ; 238: 193-9, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23098794

RESUMO

Multiple studies have reported prenatal stress as a potential risk factor for the development of autism spectrum disorder (ASD). In rodents, a significant reduction in sociability is seen in prenatally stressed offspring of genetically stress-susceptible dams. Certain dietary factors that contribute to stress reactivity may, therefore, exacerbate prenatal stress-mediated behavioral changes in adult offspring. Adults with a diet rich in omega-6 polyunsaturated fatty acids (PUFAs) display increased stress reactivity. In the current study, the effects of prenatal diet and prenatal stress on social behavior in adult offspring mice were examined. Pregnant C57BL/6J dams received either chronic variable stress or no stress, and were also placed on a control diet or a diet rich in omega-6 PUFAs, in a 2×2 design. We subsequently tested the adult offspring for sociability, anxiety, and locomotor behaviors using a 3-chambered social approach task, an elevated-plus maze, an open field task and a rotarod task. Results indicated that a maternal diet rich in omega-6 PUFAs during gestation and lactation produce changes in sociability consistent with those observed in ASD. Additionally, offspring exposed to a diet rich in omega-6 PUFAs during gestation and lactation had increased levels of anxiety in the elevated-plus maze. Prenatal stress had no effect on offspring behavior. These findings provide evidence for a possible environmental risk factor that contributes to the production of autistic-like behavior in mice.


Assuntos
Comportamento Animal/efeitos dos fármacos , Gorduras na Dieta/administração & dosagem , Ácidos Graxos Ômega-6/administração & dosagem , Lactação/fisiologia , Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Comportamento Social , Estresse Psicológico/metabolismo , Animais , Feminino , Lactação/efeitos dos fármacos , Masculino , Camundongos , Gravidez , Teste de Desempenho do Rota-Rod
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