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2.
Cell ; 158(1): 185-197, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24954535

RESUMO

Activating mutations in KRAS are among the most frequent events in diverse human carcinomas and are particularly prominent in human pancreatic ductal adenocarcinoma (PDAC). An inducible Kras(G12D)-driven mouse model of PDAC has established a critical role for sustained Kras(G12D) expression in tumor maintenance, providing a model to determine the potential for and the underlying mechanisms of Kras(G12D)-independent PDAC recurrence. Here, we show that some tumors undergo spontaneous relapse and are devoid of Kras(G12D) expression and downstream canonical MAPK signaling and instead acquire amplification and overexpression of the transcriptional coactivator Yap1. Functional studies established the role of Yap1 and the transcriptional factor Tead2 in driving Kras(G12D)-independent tumor maintenance. The Yap1/Tead2 complex acts cooperatively with E2F transcription factors to activate a cell cycle and DNA replication program. Our studies, along with corroborating evidence from human PDAC models, portend a novel mechanism of escape from oncogenic Kras addiction in PDAC.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adenocarcinoma/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Neoplasias Pancreáticas/metabolismo , Fosfoproteínas/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Adenocarcinoma/patologia , Animais , Carcinoma Ductal Pancreático/patologia , Ciclo Celular , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Replicação do DNA , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Fatores de Transcrição E2F/metabolismo , Humanos , Camundongos , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas/metabolismo , Fatores de Transcrição de Domínio TEA , Fatores de Transcrição/metabolismo , Proteínas de Sinalização YAP , Proteínas ras/metabolismo
3.
Cell ; 149(3): 656-70, 2012 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-22541435

RESUMO

Tumor maintenance relies on continued activity of driver oncogenes, although their rate-limiting role is highly context dependent. Oncogenic Kras mutation is the signature event in pancreatic ductal adenocarcinoma (PDAC), serving a critical role in tumor initiation. Here, an inducible Kras(G12D)-driven PDAC mouse model establishes that advanced PDAC remains strictly dependent on Kras(G12D) expression. Transcriptome and metabolomic analyses indicate that Kras(G12D) serves a vital role in controlling tumor metabolism through stimulation of glucose uptake and channeling of glucose intermediates into the hexosamine biosynthesis and pentose phosphate pathways (PPP). These studies also reveal that oncogenic Kras promotes ribose biogenesis. Unlike canonical models, we demonstrate that Kras(G12D) drives glycolysis intermediates into the nonoxidative PPP, thereby decoupling ribose biogenesis from NADP/NADPH-mediated redox control. Together, this work provides in vivo mechanistic insights into how oncogenic Kras promotes metabolic reprogramming in native tumors and illuminates potential metabolic targets that can be exploited for therapeutic benefit in PDAC.


Assuntos
Adenocarcinoma/metabolismo , Modelos Animais de Doenças , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Animais , Humanos , Camundongos , Proteínas Proto-Oncogênicas p21(ras)/genética , Transcrição Gênica
4.
Mol Pharm ; 20(1): 331-340, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36490361

RESUMO

With few curative treatments and a global yearly death rate of over 800,000, hepatocellular carcinoma (HCC) desperately needs new therapies. Although wild-type p53 gene therapy has been shown to be safe in HCC patients, it has not shown enough efficacy to merit approval. This work aims to show how p53 can be re-engineered through fusion to the pro-apoptotic BH3 protein Bcl-2 antagonist of cell death (Bad) to improve anti-HCC activity and potentially lead to a novel HCC therapeutic, p53-Bad*. p53-Bad* is a fusion of p53 and Bad, with two mutations, S112A and S136A. We determined mitochondrial localization of p53-Bad* in liver cancer cell lines with varying p53 mutation statuses via fluorescence microscopy. We defined the apoptotic activity of p53-Bad* in four liver cancer cell lines using flow cytometry. To determine the effects of p53-Bad* in vivo, we generated and analyzed transgenic zebrafish expressing hepatocyte-specific p53-Bad*. p53-Bad* localized to the mitochondria regardless of the p53 mutation status and demonstrated superior apoptotic activity over WT p53 in early, middle, and late apoptosis assays. Tumor burden in zebrafish HCC was reduced by p53-Bad* as measured by the liver-to-body mass ratio and histopathology. p53-Bad* induced significant apoptosis in zebrafish HCC as measured by TUNEL staining but did not induce apoptosis in non-HCC fish. p53-Bad* can induce apoptosis in a panel of liver cancer cell lines with varying p53 mutation statuses and induce apoptosis/reduce HCC tumor burden in vivo in zebrafish. p53-Bad* warrants further investigation as a potential new HCC therapeutic.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/metabolismo , Peixe-Zebra/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Carga Tumoral , Apoptose/genética , Proteínas Reguladoras de Apoptose/genética , Terapia Genética , Linhagem Celular Tumoral
5.
Pediatr Allergy Immunol ; 34(9): e14022, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37747753

RESUMO

BACKGROUND: Due to the recency of the postbiotic field, no head-to-head postbiotic studies have investigated its biotherapeutic potential for atopic dermatitis (AD). No network meta-analysis (NMA) has been conducted to synthesize relevant studies comparing postbiotic interventions for AD. OBJECTIVE: To assess the comparative efficacy and safety of postbiotic strains in the treatment of pediatric AD. METHODOLOGY: This was an NMA of randomized controlled studies that evaluated postbiotics in treating pediatric AD. Systematic search of databases and registers from inception to November 30, 2022. Three authors independently performed the search, screening, and appraisal using the Cochrane risk-of-bias tool version 2 and data extraction. Data analysis was performed using STATA14 software. RESULTS: Nine studies evaluated eight postbiotic preparations. Lactobacillus rhamnosus IDCC 3201 (LR) ranked highest in the efficacy outcome. Compared to placebo, LR may be effective in reducing symptoms of atopic dermatitis in the main analysis (SMD -0.53, 95%CI -1.02 to -0.04) and sensitivity analysis involving studies that used SCORAD (MD -5.52, 95% CI -10.46 to -0.58), based on low-certainty evidence. Based on moderate-certainty evidence, LR probably did not increase the risk of adverse events (RR 0.97, 95% CI 0.79, 1.21). Although Lactobacillus paracasei GM080 (LP2) ranked highest in the safety outcome, it may not reduce AD symptoms compared to placebo (SMD -0.03, 95% CI -0.37, 0.32) based on low-certainty evidence. CONCLUSION: LR showed significant benefits in children with AD based on low-certainty evidence. Further investigation of LR is recommended.


Assuntos
Dermatite Atópica , Lacticaseibacillus paracasei , Lacticaseibacillus rhamnosus , Humanos , Criança , Metanálise em Rede , Dermatite Atópica/terapia , Bases de Dados Factuais
6.
BMC Infect Dis ; 23(1): 750, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37915006

RESUMO

BACKGROUND: Variation in immune response to COVID-19 vaccines is observed among different ethnicities. We aimed to describe the reinfection rates, change in antibody titers, and adverse events among Filipinos. METHODS: This is a secondary analysis of a cohort study of 307 participants within one year of having COVID-19 infection. We measured COVID-19 antibody levels at pre-determined timepoints (Days 21, 90, 180, 270, and 360 from initial infection). We monitored for COVID-19 symptoms and obtained details on COVID-19 vaccination. An adjudication committee classified the participants as probable, possible, or unlikely COVID-19 reinfection. We determined the probable reinfection rate, adverse events, and the geometric mean titer (GMT) ratio of pre- and post-vaccination antibody levels according to type and brand of COVID-19 vaccine. RESULTS: At the end of the follow-up period, 287 (93.5%) out of 307 study participants were fully vaccinated, 1 was partially vaccinated (0.3%), and 19 were unvaccinated (6.2%). Among the fully vaccinated participants, those given mRNA vaccines had the lowest reinfection rate (19.2 cases/100 person-years, 95% CI 9.6, 38.4), followed by viral vector vaccines (29.8 cases/100 person-years, 95% CI 16.9, 52.4). We observed the highest reinfection rate among those given inactivated virus vaccines (32.7 cases/100 person-years, 95% CI 23.6, 45.3). The reinfection rate was 8.6 cases/100 person-years (95% CI 4.1, 17.9) for unvaccinated participants and 3.6 cases/100 person-years (95% CI 0.5, 25.3) for partially vaccinated participants. We observed the largest rise in antibody titers among those given mRNA vaccines (GMT ratio 288.5), and the smallest rise among those given inactivated virus vaccines (GMT ratio 16.7). We observed the highest percentage of adverse events following immunization with viral vector vaccines (63.8%), followed by mRNA vaccines (62.7%), and the lowest for inactivated virus vaccines (34.7%). No serious adverse events were reported. CONCLUSION: Vaccinees given the mRNA vaccines had the lowest reinfection rate and the highest rise in antibody titers. Vaccinees given inactivated virus vaccines had the highest reinfection rate, smallest rise in antibody titers, and lowest percentage of adverse events. The small sample size and imbalanced distribution of the type of vaccines received limits the external generalizability of our results. STUDY REGISTRATION: The cohort study was registered at the Philippine Health Research Registry on December 14, 2020 (PHRR201214-003199).


Assuntos
COVID-19 , Vacinas Virais , Humanos , Vacinas contra COVID-19/efeitos adversos , COVID-19/epidemiologia , Estudos de Coortes , Filipinas/epidemiologia , Reinfecção/epidemiologia , Reinfecção/induzido quimicamente , Vacinação/efeitos adversos , Vacinação/métodos , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de mRNA , Anticorpos Antivirais
7.
Am J Geriatr Psychiatry ; 30(3): 419-423, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34400046

RESUMO

Older adults with serious mental illness (SMI) experience increased medical comorbidities, disability, and early mortality, but little is known about how they perceive the process of aging. This study explored attitudes and beliefs about aging among n = 20 middle aged and older adults (M = 59.8 years; range 47-66) with SMI in a state psychiatric hospital. We conducted semistructured interviews using the Attitudes to Ageing Questionnaire (AAQ) and analyzed narrative accounts using a grounded theory approach. The mean scores of overall attitudes toward aging and of the subscale of perception of psychological growth were both positive compared to a neutral rating (p = 0.026 and p = 0.004, respectively). Study participants rated their experience on the subscales of psychosocial loss and physical health change as neutral. Despite substantial psychiatric, medical, and functional disabilities, older adults with SMI in this study of psychiatric inpatients perceived the process of aging as generally positive, suggesting resilience and potential positive emotional growth in older age.


Assuntos
Envelhecimento , Transtornos Mentais , Idoso , Envelhecimento/psicologia , Atitude , Humanos , Pessoa de Meia-Idade , Inquéritos e Questionários
8.
Pediatr Allergy Immunol ; 32(1): 124-136, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32524647

RESUMO

BACKGROUND: The current evidence on the use of probiotics in treating atopic dermatitis is inconclusive. This study determined the comparative effectiveness of the different types of probiotic strains in treating pediatric atopic dermatitis. METHODOLOGY: Systematic and manual search for all randomized controlled trials available from inception until January 31, 2020, was done. Two independent authors conducted the search, screening, appraisal, and data abstraction. Network meta-analysis was conducted using STATA 14 software. RESULTS: Twenty-two studies involving 28 different probiotic strains were included. The top three ranked probiotic strains in terms of efficacy are Mix1 (Bifidobacterium animalis subsp lactis CECT 8145, Bifidobacterium longum CECT 7347, and Lactobacillus casei CECT 9104); Lactobacillus casei DN-114001; and Mix6 (Bifidobacterium bifidum, Lactobacillus acidophilus, Lactobacillus casei, and Lactobacillus salivarius). Compared with placebo, Mix1 reduces atopic dermatitis symptoms with high certainty evidence (SMD -1.94, 95% CI -2.65 to -1.24; 47 participants). Mix6 compared with placebo probably reduces atopic dermatitis symptoms based on moderate certainty evidence (SMD -0.85, 95% CI -1.50 to -0.20; 40 participants). Lactobacillus casei DN-114001 compared with placebo may reduce atopic dermatitis symptoms based on low certainty evidence (SMD -1.35, 95% CI -2.04 to -0.65). In terms of safety, the highest ranked strain is Lactobacillus fermentum VRI-003, while the lowest ranked strain is Lactobacillus rhamnosus GG. CONCLUSION: Certain probiotic preparations show benefit in reducing allergic symptoms in pediatric atopic dermatitis.


Assuntos
Bifidobacterium animalis , Dermatite Atópica , Lacticaseibacillus rhamnosus , Probióticos , Criança , Dermatite Atópica/terapia , Humanos , Metanálise em Rede , Probióticos/uso terapêutico
9.
Pediatr Allergy Immunol ; 32(6): 1255-1270, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33811784

RESUMO

BACKGROUND: Atopic dermatitis is the most common chronic skin disease affecting the pediatric population. Probiotics have been proposed to be effective in preventing the development of pediatric atopic dermatitis. Although studies show promise for the use of probiotics, the evidence is still inconclusive due to significant heterogeneity and imprecision. OBJECTIVE: To determine the comparative effectiveness of the different types of probiotic strains in preventing the development of atopic dermatitis among pediatric patients. METHODOLOGY: A systematic search of Cochrane Library, MEDLINE, TRIP Database, and Centre for Research and Dissemination was conducted. Manual search of the reference lists and search for unpublished articles were also done. All randomized controlled trials available from inception until April 12, 2020, on the use of probiotics in the prevention of atopic dermatitis among children were included. The comparator groups considered are other probiotic strains and placebo. The primary outcome of interest was the development of atopic dermatitis. Two authors independently searched for articles, screened the articles for inclusion, appraised the articles using the Cochrane risk of bias tool version 2, and extracted the data. In case of disagreement, the two authors discussed the source of disagreement until consensus was reached. If consensus was not reached, an independent third party reviewer was consulted. Frequentist network meta-analysis was conducted using STATA 14 software. The ranking probabilities and surface under the cumulative ranking curve (SUCRA) values were obtained to determine ranking of the different probiotic strains based on efficacy and safety data. RESULTS: We included 21 original studies represented by 35 records and a total of 5406 children with atopic dermatitis as diagnosed by clinicians or fulfillment of validated diagnostic criteria. All studies were randomized placebo-controlled trials. The top 3 probiotic preparations in terms of efficacy in reducing the risk of atopic dermatitis are Mix8 (Lactobacillus paracasei ST11, Bifidobacterium longum BL999), LP (Lactobacillus paracasei ssp paracasei F19) and Mix3 (Lactobacillus rhamnosus GG, Bifidobacterium animalis ssp lactis Bb-12). Mix8 compared with placebo probably reduces the risk of atopic dermatitis based on low-quality evidence (RR = 0.46, 95% CI 0.25-0.85). Mix3 compared with placebo also probably reduces the risk of atopic dermatitis based on low-quality evidence (RR = 0.50, 95% CI 0.27-0.94). It is uncertain whether LP compared with placebo reduces the risk of atopic dermatitis due to very-low-quality certainty of evidence (RR = 0.49, 95% CI 0.20-1.19). In terms of adverse events, LGG may slightly lead to less adverse events compared with placebo based on low-quality evidence (RR = 0.70, 95% CI 0.32-1.52). Mix4 may slightly lead to more adverse events compared with placebo based on low-quality evidence (RR = 1.06, 95% CI 0.02-51.88). Based on subgroup analysis of studies involving infants, Mix3 compared with placebo probably reduces the risk of atopic dermatitis based on low-quality evidence (RR = 0.46, 95% CI 0.22-0.97). In the subgroup analysis of studies where probiotics were administered to pregnant women and to infants, LRH compared with placebo probably reduces the risk of atopic dermatitis based on moderate-quality evidence (RR = 0.54, 95% CI 0.26-1.11). CONCLUSION: Certain probiotic preparations demonstrate efficacy in reducing the risk of developing atopic dermatitis when administered to pregnant women, infants, or both.


Assuntos
Bifidobacterium animalis , Dermatite Atópica , Eczema , Probióticos , Criança , Dermatite Atópica/prevenção & controle , Feminino , Humanos , Lactente , Metanálise em Rede , Gravidez , Probióticos/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Mol Pharm ; 16(8): 3386-3398, 2019 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-31241338

RESUMO

Clinical trials involving p53 gene therapy for ovarian cancer failed due to the dominant negative inhibition of wild-type p53 and multiple genetic aberrations in ovarian cancer. To overcome this problem, we have designed a more potent chimeric gene fusion, called p53-Bad, that combines p53 with the mitochondrial pro-apoptotic factor Bad. Unlike wild-type p53, which acts as a nuclear transcription factor, this novel p53-Bad construct has multiple unique mechanisms of action including a direct and rapid apoptotic effect at the mitochondria. The mitochondrial localization, transcription activity, and apoptotic activity of the constructs were tested. The results suggest that p53 can be effectively targeted to the mitochondria by controlling the phosphorylation of pro-apoptotic Bad, which can only localize to the mitochondria when Ser-112 and Ser-136 of Bad are unphosphorylated. By introducing S112A and S136A mutations, p53-Bad fusion cannot be phosphorylated at these two sites and always localizes to the mitochondria. p53-Bad constructs also have superior activity over p53 and Bad alone. The apoptotic activity is consistent in many ovarian cancer cell lines regardless of the endogenous p53 status. Both p53 and the BH3 domain of Bad contribute to the superior activity of p53-Bad. Our data suggests that p53-Bad fusions are capable of inducing apoptosis and should be further pursued for gene therapy for ovarian cancer.


Assuntos
Terapia Genética/métodos , Mitocôndrias/genética , Neoplasias Ovarianas/terapia , Proteínas Recombinantes de Fusão/genética , Proteína Supressora de Tumor p53/genética , Proteína de Morte Celular Associada a bcl/genética , Apoptose/genética , Linhagem Celular Tumoral , Feminino , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Humanos , Mitocôndrias/patologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Fosforilação/genética , Plasmídeos/genética , Proteínas Recombinantes de Fusão/metabolismo , Transfecção , Proteína Supressora de Tumor p53/metabolismo , Proteína de Morte Celular Associada a bcl/metabolismo
11.
Chemistry ; 23(29): 7087-7092, 2017 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-28345248

RESUMO

The application of thiol-yne/thiol-ene reactions to synthesize mono- and bicyclic-stapled peptides and proteins is reported. First, a thiol-ene-based peptide-stapling method in aqueous conditions was developed. This method enabled the efficient stapling of recombinantly expressed coil-coiled proteins. The resulting stapled protein demonstrated higher stability in its secondary structure than the unstapled version. Furthermore, a thiol-yne coupling was performed by using an α,ω-diyne to react with two cysteine residues to synthesize a stapled peptide with two vinyl sulfide groups. The stapled peptide could further react with another biscysteine peptide to yield a bicyclic stapled peptide with enhanced properties. For example, the cell permeability of a stapled peptide was further increased by appending an oligoarginine cell-penetrating peptide. The robustness and versatility of thiol-yne/thiol-ene reactions that can be applied to both synthetic and expressed peptides and proteins were demonstrated.


Assuntos
Peptídeos Penetradores de Células/química , Compostos de Sulfidrila/química , Sulfetos/química , Sequência de Aminoácidos , Cromatografia em Gel , Ciclização , Cisteína/química , Estrutura Secundária de Proteína
12.
Mol Pharm ; 12(5): 1412-21, 2015 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-25858426

RESUMO

The oncoprotein Bcr-Abl is the cause of chronic myeloid leukemia (CML).1 Current therapies target the tyrosine kinase domain of Bcr-Abl, but resistance to these drugs is common.2 Bcr-Abl homo-oligomerization via its N-terminal coiled-coil (CC) domain is required for tyrosine kinase activity.3 Our previous work has shown that it is possible to inhibit Bcr-Abl activity by targeting the CC domain with a peptidomemetic known as CC(mut3), delivered as a plasmid.4 In this study, CC(mut3) is delivered to cells as a protein by utilizing a leukemia-specific cell-penetrating peptide (CPP).5 Here, recombinant CPP-CC(mut3) was expressed, purified, and tested for its antioncogenic activity. CPP-CC(mut3) was able to enter two leukemic cell lines (K562 and Ba/F3-P210) and inhibit Bcr-Abl activity as shown by induction of necrosis/apoptosis via 7-AAD/Annexin V staining, reduction of oncogenic potential in colony forming assays, reduction of cell proliferation, and inhibition of Bcr-Abl phosphorylation (kinase activity). Further, CPP-CC(mut3) did not enter nonleukemic cell lines (HEK293 and MCF-7). While CPP-CC(mut3) was able to enter the parental, nonleukemic Bcr-Abl(-) Ba/F3 pro-B cell line, it revealed no signs of activity in the assays performed, as expected. These results indicate the feasibility of using CPP-CC(mut3) as a therapeutic against CML.


Assuntos
Peptídeos Penetradores de Células/farmacologia , Proteínas de Fusão bcr-abl/metabolismo , Anexina A5/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Peptídeos Penetradores de Células/química , Ativação Enzimática/efeitos dos fármacos , Células HEK293 , Humanos , Células K562 , Necrose/induzido quimicamente , Fosforilação/efeitos dos fármacos , Estrutura Terciária de Proteína , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
13.
Mol Pharm ; 11(7): 2442-52, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-24836513

RESUMO

The use of the tumor suppressor p53 for gene therapy of cancer is limited by the dominant negative inactivating effect of mutant endogenous p53 in cancer cells. We have shown previously that swapping the tetramerization domain (TD) of p53 with the coiled-coil (CC) from Bcr allows for our chimeric p53 (p53-CC) to evade hetero-oligomerization with endogenous mutant p53. This enhances the utility of this construct, p53-CC, for cancer gene therapy. Because domain swapping to create p53-CC could result in p53-CC interacting with endogenous Bcr, which is ubiquitous in cells, modifications on the CC domain are necessary to minimize potential interactions with Bcr. Hence, we investigated the possible design of mutations that will improve homodimerization of CC mutants and disfavor hetero-oligomerization with wild-type CC (CCwt), with the goal of minimizing potential interactions with endogenous Bcr in cells. This involved integrated computational and experimental approaches to rationally design an enhanced version of our chimeric p53-CC tumor suppressor. Indeed, the resulting lead candidate p53-CCmutE34K-R55E avoids binding to endogenous Bcr and retains p53 tumor suppressor activity. Specifically, p53-CCmutE34K-R55E exhibits potent apoptotic activity in a variety of cancer cell lines, regardless of p53 status (in cells with mutant p53, wild-type p53, or p53-null cells). This construct overcomes the dominant negative effect limitation of wt p53 and has high significance for future gene therapy for treatment of cancers characterized by p53 dysfunction, which represent over half of all human cancers.


Assuntos
Genes Supressores de Tumor/fisiologia , Proteína Supressora de Tumor p53/genética , Animais , Apoptose/genética , Células COS , Linhagem Celular Tumoral , Chlorocebus aethiops , Humanos , Células MCF-7 , Mutação/genética , Polimerização
14.
Pharm Res ; 31(9): 2503-15, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24633417

RESUMO

PURPOSE: p53 targeted to the mitochondria is the fastest and most direct pathway for executing p53 death signaling. The purpose of this work was to determine if mitochondrial targeting signals (MTSs) from pro-apoptotic Bak and Bax are capable of targeting p53 to the mitochondria and inducing rapid apoptosis. METHODS: p53 and its DNA-binding domain (DBD) were fused to MTSs from Bak (p53-BakMTS, DBD-BakMTS) or Bax (p53-BaxMTS, DBD-BaxMTS). Mitochondrial localization was tested via fluorescence microscopy in 1471.1 cells, and apoptosis was detected via 7-AAD in breast (T47D), non-small cell lung (H1373), ovarian (SKOV-3) and cervical (HeLa) cancer cells. To determine that apoptosis is via the intrinsic apoptotic pathway, TMRE and caspase-9 assays were conducted. Finally, the involvement of p53/Bak specific pathway was tested. RESULTS: MTSs from Bak and Bax are capable of targeting p53 to the mitochondria, and p53-BakMTS and p53-BaxMTS cause apoptosis through the intrinsic apoptotic pathway. Additionally, p53-BakMTS, DBD-BakMTS, p53-BaxMTS and DBD-BaxMTS caused apoptosis in T47D, H1373, SKOV-3 and HeLa cells. The apoptotic mechanism of p53-BakMTS and DBD-BakMTS was Bak dependent. CONCLUSION: Our data demonstrates that p53-BakMTS (or BaxMTS) and DBD-BakMTS (or BaxMTS) cause apoptosis at the mitochondria and can be used as a potential gene therapeutic in cancer.


Assuntos
Mitocôndrias/metabolismo , Neoplasias/terapia , Proteínas Recombinantes de Fusão/genética , Proteína Supressora de Tumor p53/genética , Proteína Killer-Antagonista Homóloga a bcl-2/genética , Proteína X Associada a bcl-2/genética , Sequência de Aminoácidos , Apoptose , Linhagem Celular Tumoral , Terapia Genética , Células HeLa , Humanos , Mitocôndrias/genética , Dados de Sequência Molecular , Neoplasias/genética , Neoplasias/metabolismo , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/química , Transdução de Sinais , Transfecção , Proteína Supressora de Tumor p53/química , Proteína Killer-Antagonista Homóloga a bcl-2/química , Proteína X Associada a bcl-2/química
15.
BMC Health Serv Res ; 14: 595, 2014 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-25432511

RESUMO

BACKGROUND: Reimbursement policies for anti-cancer drugs vary among countries even though they rely on the same clinical evidence. We compared the pattern of publicly funded drug programs and analyzed major factors influencing the differences. METHODS: We investigated reimbursement policies for 19 indications with targeted anti-cancer drugs that are used variably across ten countries. The available incremental cost-effectiveness ratio (ICER) data were retrieved for each indication. Based on the comparison between actual reimbursement decisions and the ICERs, we formulated a reimbursement adequacy index (RAI): calculating the proportion of cost-effective decisions, either reimbursement of cost-effective indications or non-reimbursement of cost-ineffective indications, out of the total number of indications for each country. The relationship between RAI and other indices were analyzed, including governmental dependency on health technology assessment, as well as other parameters for health expenditure. All the data used in this study were gathered from sources publicly available online. RESULTS: Japan and France were the most likely to reimburse indications (16/19), whereas Sweden and the United Kingdom were the least likely to reimburse them (5/19 and 6/19, respectively). Indications with high cost-effectiveness values were more likely to be reimbursed (ρ = -0.68, P = 0.001). The three countries with high RAI scores each had a healthcare system that was financed by general taxation. CONCLUSIONS: Although reimbursement policies for anti-cancer drugs vary among countries, we found a strong correlation of reimbursements for those indications with lower ICERs. Countries with healthcare systems financed by general taxation demonstrated greater cost-effectiveness as evidenced by reimbursement decisions of anti-cancer drugs.


Assuntos
Antineoplásicos/economia , Reembolso de Seguro de Saúde , Internacionalidade , Antineoplásicos/uso terapêutico , Análise Custo-Benefício , França , Gastos em Saúde , Humanos , Japão , Suécia , Avaliação da Tecnologia Biomédica/economia , Reino Unido
16.
Psychiatr Serv ; : appips20230623, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38938091

RESUMO

OBJECTIVE: The impact of obtaining second-opinion consultations on diagnoses of schizophrenia spectrum disorders was evaluated. METHODS: A retrospective chart review was conducted for 177 patients referred to a psychosis consultation service at an academic medical center from January 1, 2017, to October 1, 2023; these consultations aimed to clarify a diagnosis of psychosis. Diagnoses made before and after consultations were compared, and treatment recommendations resulting from the consultation visit were summarized. RESULTS: Among patients without a preconsultation diagnosis of schizophrenia, 28% (N=28 of 100) received a postconsultation diagnosis of schizophrenia. Among 62 patients with a postconsultation diagnosis of treatment-resistant schizophrenia (TRS), 56% (N=35) received this diagnosis only after consultation. Nearly all of these patients were advised to begin taking clozapine, and electroconvulsive therapy was less commonly recommended. CONCLUSIONS: Expert consultation facilitates timely identification and optimal treatment of schizophrenia and its more severe subtype, TRS.

17.
J Phys Chem B ; 128(27): 6476-6491, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38951498

RESUMO

The chimeric oncoprotein Bcr-Abl is the causative agent of virtually all chronic myeloid leukemias and a subset of acute lymphoblastic leukemias. As a result of the so-called Philadelphia chromosome translocation t(9;22), Bcr-Abl manifests as a constitutively active tyrosine kinase, which promotes leukemogenesis by activation of cell cycle signaling pathways. Constitutive and oncogenic activation is mediated by an N-terminal coiled-coil oligomerization domain in Bcr (Bcr-CC), presenting a therapeutic target for inhibition of Bcr-Abl activity toward the treatment of Bcr-Abl+ leukemias. Previously, we demonstrated that a rationally designed Bcr-CC mutant, CCmut3, exerts a dominant negative effect upon Bcr-Abl activity by preferential oligomerization with Bcr-CC. Moreover, we have shown that conjugation to a leukemia-specific cell-penetrating peptide (CPP-CCmut3) improves intracellular delivery and activity. However, our full-length CPP-CCmut3 construct (81 aa) is encumbered by an intrinsically high degree of conformational variability and susceptibility to proteolytic degradation relative to traditional small-molecule therapeutics. Here, we iterate a new generation of CCmut3 inhibitors against Bcr-CC-mediated Bcr-Abl assembly designed to address these constraints through incorporation of all-hydrocarbon staples spanning i and i + 7 positions in α-helix 2 (CPP-CCmut3-st). We utilize computational modeling and biomolecular simulation to evaluate single- and double-stapled CCmut3 candidates in silico for dynamics and binding energetics. We further model a truncated system characterized by the deletion of α-helix 1 and the flexible loop linker, which are known to impart high conformational variability. To study the impact of the N-terminal cyclic CPP toward model stability and inhibitor activity, we also model the full-length and truncated systems devoid of the CPP, with a cyclized CPP, and with an open-configuration CPP, for a total of six systems that comprise our library. From this library, we present lead-stapled peptide candidates to be synthesized and evaluated experimentally as our next iteration of inhibitors against Bcr-Abl.


Assuntos
Proteínas de Fusão bcr-abl , Leucemia Mielogênica Crônica BCR-ABL Positiva , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Proteínas de Fusão bcr-abl/metabolismo , Proteínas de Fusão bcr-abl/química , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Humanos , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/metabolismo , Modelos Moleculares , Simulação de Dinâmica Molecular , Antineoplásicos/química , Antineoplásicos/farmacologia , Peptídeos Penetradores de Células/química , Peptídeos Penetradores de Células/farmacologia , Peptídeos Penetradores de Células/metabolismo
18.
Artigo em Inglês | MEDLINE | ID: mdl-38996400

RESUMO

The Psychiatric Consultation Service at Massachusetts General Hospital sees medical and surgical inpatients with comorbid psychiatric symptoms and conditions. During their twice-weekly rounds, Dr Stern and other members of the Consultation Service discuss diagnosis and management of hospitalized patients with complex medical or surgical problems who also demonstrate psychiatric symptoms or conditions. These discussions have given rise to rounds reports that will prove useful for clinicians practicing at the interface of medicine and psychiatry.Prim Care Companion CNS Disord 2024;26(4):23f03692. Author affiliations are listed at the end of this article.


Assuntos
Esquizofrenia Resistente ao Tratamento , Humanos , Esquizofrenia Resistente ao Tratamento/terapia , Esquizofrenia Resistente ao Tratamento/diagnóstico , Antipsicóticos/uso terapêutico
19.
Artigo em Inglês | MEDLINE | ID: mdl-39094074

RESUMO

The Psychiatric Consultation Service at Massachusetts General Hospital sees medical and surgical inpatients with comorbid psychiatric symptoms and conditions. During their twice-weekly rounds, Dr Stern and other members of the Consultation Service discuss diagnosis and management of hospitalized patients with complex medical or surgical problems who also demonstrate psychiatric symptoms or conditions. These discussions have given rise to rounds reports that will prove useful for clinicians practicing at the interface of medicine and psychiatry.Prim Care Companion CNS Disord 2024;26(4):23f03702. Author affiliations are listed at the end of this article.


Assuntos
Antipsicóticos , Clozapina , Humanos , Clozapina/efeitos adversos , Clozapina/uso terapêutico , Antipsicóticos/uso terapêutico , Antipsicóticos/efeitos adversos , Esquizofrenia/tratamento farmacológico
20.
Acta Med Philipp ; 58(14): 50-66, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39238554

RESUMO

Background: Remdesivir is an intravenously administered antiviral drug that inhibits RNA-dependent RNA polymerase. In vitro studies have shown that remdesivir can inhibit the growth of the COVID-19 virus in infected Vero cells and can inhibit infection in human cell lines. Objective: To determine the efficacy and safety of remdesivir in treating patients with COVID-19 infection. Methods: A systematic search of electronic medical literature databases was done from inception until September 4, 2022. Search for ongoing studies and preprints was also done. Risk of bias assessment was done using Cochrane risk of bias tool version 2.0. Measures of effect used were relative risk (RR) and 95% confidence interval (CI). Subgroup analysis by disease severity was preplanned. The estimates for efficacy and safety of remdesivir was calculated using Review Manager 5.4 software. Results: Nine randomized controlled trials with 13,085 participants were identified. Eight of the included studies recruited confirmed COVID-19 patients needing hospitalization, while one study limited recruitment to non-hospitalized patients. Remdesivir showed significant benefit for outpatients with mild to moderate disease with at least one risk factor for disease progression in terms of COVID 19-related hospitalization (RR 0.13 95% CI 0.03 to 0.59), all-cause hospitalization (RR 0.28, 95% CI 0.10 to 0.75), and need for medically-attended visits (RR 0.19, 95% CI 0.07 to 0.56). For hospitalized patients, remdesivir had a slight benefit in reducing all-cause mortality at day 28 (RR 0.90, 95% CI 0.83 to 0.98). Subgroup analysis by disease severity showed a trend towards reduction in mortality among those with severe disease (RR 0.61, 95% CI 0.35 to 1.07), with no effect on those with critical disease (RR 0.96, 95% CI 0.87 to 1.04), and inconclusive effect for those with mild-moderate disease (RR 0.74, 95% CI 0.49 to 1.11). Remdesivir showed benefit in decreasing clinical deterioration (RR 0.75, 95% CI 0.61 to 0.89), improving recovery rate (RR 1.07, 95% CI 1.01 to 1.13), and reducing the need for mechanical ventilation (RR 0.68, 95% CI 0.51 to 0.90). There was inconclusive effect on the need for ICU admission (RR 0.98, 95% CI 0.43 to 2.22). No increased risk of adverse events (RR 0.98, 95% CI 0.91 to 1.06), including serious adverse events (RR 0.77, 95% CI 0.57 to 1.03), was seen. Discussion: Based on the available evidence, remdesivir shows benefit in the treatment for patients with mild, moderate, and severe COVID-19 infection. However, there was no benefit in mortality noted among those with critical disease requiring mechanical ventilation. Remdesivir demonstrated a good safety profile, with no increased risk of adverse events compared to control. These results are consistent with the international agencies' recommendations for the use of remdesivir among patients with mild, moderate or severe COVID-19 infection, but not for those with critical infection. Conclusion: Current evidence supports the use of remdesivir as treatment for selected patients with COVID-19.

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