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1.
Cancer ; 126(15): 3579-3592, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32484926

RESUMO

BACKGROUND: Poor outcomes for patients with ovarian cancer relate to dormant, drug-resistant cancer cells that survive after primary surgery and chemotherapy. Ovarian cancer (OvCa) cells persist in poorly vascularized scars on the peritoneal surface and depend on autophagy to survive nutrient deprivation. The authors have sought drugs that target autophagic cancer cells selectively to eliminate residual disease. METHODS: By using unbiased small-interfering RNA (siRNA) screens, the authors observed that knockdown of anaplastic lymphoma kinase (ALK) reduced the survival of autophagic OvCa cells. Small-molecule ALK inhibitors were evaluated for their selective toxicity against autophagic OvCa cell lines and xenografts. Autophagy was induced by reexpression of GTP-binding protein Di-Ras3 (DIRAS3) or serum starvation and was evaluated with Western blot analysis, fluorescence imaging, and transmission electron microscopy. Signaling pathways required for crizotinib-induced apoptosis of autophagic cells were explored with flow cytometric analysis, Western blot analysis, short-hairpin RNA knockdown of autophagic proteins, and small-molecule inhibitors of STAT3 and BCL-2. RESULTS: Induction of autophagy by reexpression of DIRAS3 or serum starvation in multiple OvCa cell lines significantly reduced the 50% inhibitory concentration of crizotinib and other ALK inhibitors. In 2 human OvCa xenograft models, the DIRAS3-expressing tumors treated with crizotinib had significantly decreased tumor burden and long-term survival in 67% to 79% of mice. Crizotinib treatment of autophagic cancer cells further enhanced autophagy and induced autophagy-mediated apoptosis by decreasing phosphorylated STAT3 and BCL-2 signaling. CONCLUSIONS: Crizotinib may eliminate dormant, autophagic, drug-resistant OvCa cells that remain after conventional cytoreductive surgery and combination chemotherapy. A clinical trial of ALK inhibitors as maintenance therapy after second-look operations should be seriously considered.


Assuntos
Quinase do Linfoma Anaplásico/genética , Neoplasias Ovarianas/tratamento farmacológico , Fator de Transcrição STAT3/genética , Proteínas rho de Ligação ao GTP/genética , Quinase do Linfoma Anaplásico/antagonistas & inibidores , Animais , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Linhagem da Célula/genética , Sobrevivência Celular/genética , Crizotinibe/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Xenoenxertos , Humanos , Camundongos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Inibidores de Proteínas Quinases/farmacologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Transdução de Sinais/efeitos dos fármacos
2.
J Community Health ; 45(1): 48-54, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31392602

RESUMO

Human Papillomavirus (HPV) is the most common sexually transmitted infection (STI) in the United States. Despite numerous studies proving the safety and efficacy of the HPV vaccine, immunization rates remain low, especially among underserved populations. To identify factors contributing to low HPV vaccination rates, patients at a federally qualified health center in Kalamazoo MI were surveyed. Surveys were administered during routine patient visits to determine self-reported vaccination status and vaccination barriers. A total of 98 vaccine-eligible (males/females, ages 9-26 years old) patients/guardians completed the survey. In all, 46% of respondents completed the multi-dose vaccination course, and 56% of those identified as female. White patients reported higher vaccination rates (50%) than patients of color (45%). Of those vaccinated, the most common reason was "physician recommendation" (39%). Those not fully vaccinated most commonly reported being "too young" (39%). Importantly, individuals who had begun, but not completed, the vaccination course reported that their provider had not spoken to them about future vaccines in the series (74%). This study revealed disparities in vaccination rates between the sexes and racial groups, and emphasized the influential role of physician's recommendation on vaccination. Interestingly, other frequently cited barriers to vaccination-an association with sex, personal/religious beliefs, efficacy-proved to be insignificant barriers for this population. Instead, age-related misunderstandings and lack of consistent physician communication about vaccination provided significant barriers. Based on our results, education and reminders about the HPV vaccine by providers is a significant tool to maximize vaccination coverage.


Assuntos
Vacinas contra Papillomavirus , Vacinação , Adolescente , Adulto , Criança , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Esquemas de Imunização , Masculino , Michigan , Infecções por Papillomavirus/prevenção & controle , Inquéritos e Questionários , Vacinação/psicologia , Vacinação/estatística & dados numéricos , Adulto Jovem
3.
Chem Commun (Camb) ; 59(65): 9836-9839, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37525990

RESUMO

Peptide chemists seek rapid methods combined with facile purification when producing disulphide bonds post solid-phase synthesis. Current methods typically require long reaction times of up to two days, can result in side-products from over-oxidation and/or degradation, require organic solvents, and/or require challenging purification. Herein, we describe a rapid, green, and facile oxidation of a series of peptides with up to three disulphide bonds. The method was conducted in aqueous solution, in air, utilizing the biocompatible corrin ring-containing compound dicyanocobinamide, and offers reaction times under 1 hour with simple one step removal of the catalyst.


Assuntos
Dissulfetos , Água , Dissulfetos/química , Peptídeos
4.
JAMA Netw Open ; 5(4): e227852, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35438754

RESUMO

Importance: SARS-CoV-2 entry requires the TMPRSS2 cell surface protease. Antiandrogen therapies reduce expression of TMPRSS2. Objective: To determine if temporary androgen suppression induced by degarelix improves clinical outcomes of inpatients hospitalized with COVID-19. Design, Setting, and Participants: The Hormonal Intervention for the Treatment in Veterans With COVID-19 Requiring Hospitalization (HITCH) phase 2, placebo-controlled, double-blind, randomized clinical trial compared efficacy of degarelix plus standard care vs placebo plus standard care on clinical outcomes in men hospitalized with COVID-19 but not requiring invasive mechanical ventilation. Inpatients were enrolled at 14 Department of Veterans Affairs hospitals from July 22, 2020, to April 8, 2021. Data were analyzed from August 9 to October 15, 2021. Interventions: Patients stratified by age, history of hypertension, and disease severity were centrally randomized 2:1 to degarelix, (1-time subcutaneous dose of 240 mg) or a saline placebo. Standard care included but was not limited to supplemental oxygen, antibiotics, vasopressor support, peritoneal dialysis or hemodialysis, intravenous fluids, remdesivir, convalescent plasma, and dexamethasone. Main Outcomes and Measures: The composite primary end point was mortality, ongoing need for hospitalization, or requirement for mechanical ventilation at day 15 after randomization. Secondary end points were time to clinical improvement, inpatient mortality, length of hospitalization, duration of mechanical ventilation, time to achieve a temperature within reference range, maximum severity of COVID-19, and the composite end point at 30 days. Results: The trial was stopped for futility after the planned interim analysis, at which time there were 96 evaluable patients, including 62 patients randomized to the degarelix group and 34 patients in the placebo group, out of 198 initially planned. The median (range) age was 70.5 (48-85) years. Common comorbidities included chronic obstructive pulmonary disorder (15 patients [15.6%]), hypertension (75 patients [78.1%]), cardiovascular disease (27 patients [28.1%]), asthma (12 patients [12.5%]), diabetes (49 patients [51.0%]), and chronic respiratory failure requiring supplemental oxygen at baseline prior to COVID-19 (9 patients [9.4%]). For the primary end point, there was no significant difference between the degarelix and placebo groups (19 patients [30.6%] vs 9 patients [26.5%]; P = .67). Similarly, no differences were observed between degarelix and placebo groups in any secondary end points, including inpatient mortality (11 patients [17.7%] vs 6 patients [17.6%]) or all-cause mortality (11 patients [17.7%] vs 7 patents [20.6%]). There were no differences between degarelix and placebo groups in the overall rates of adverse events (13 patients [21.0%] vs 8 patients [23.5%) and serious adverse events (19 patients [30.6%] vs 13 patients [32.4%]), nor unexpected safety concerns. Conclusions and Relevance: In this randomized clinical trial of androgen suppression vs placebo and usual care for men hospitalized with COVID-19, degarelix did not result in amelioration of COVID-19 severity. Trial Registration: ClinicalTrials.gov Identifier: NCT04397718.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , Hipertensão , Idoso , Idoso de 80 Anos ou mais , Androgênios , COVID-19/terapia , Hospitalização , Humanos , Imunização Passiva , Masculino , Oxigênio , SARS-CoV-2 , Resultado do Tratamento , Estados Unidos , Soroterapia para COVID-19
5.
Trials ; 22(1): 431, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34225789

RESUMO

BACKGROUND: Therapeutic targeting of host-cell factors required for SARS-CoV-2 entry is an alternative strategy to ameliorate COVID-19 severity. SARS-CoV-2 entry into lung epithelium requires the TMPRSS2 cell surface protease. Pre-clinical and correlative data in humans suggest that anti-androgenic therapies can reduce the expression of TMPRSS2 on lung epithelium. Accordingly, we hypothesize that therapeutic targeting of androgen receptor signaling via degarelix, a luteinizing hormone-releasing hormone (LHRH) antagonist, will suppress COVID-19 infection and ameliorate symptom severity. METHODS: This is a randomized phase 2, placebo-controlled, double-blind clinical trial in 198 patients to compare efficacy of degarelix plus best supportive care versus placebo plus best supportive care on improving the clinical outcomes of male Veterans who have been hospitalized due to COVID-19. Enrolled patients must have documented infection with SARS-CoV-2 based on a positive reverse transcriptase polymerase chain reaction result performed on a nasopharyngeal swab and have a severity of illness of level 3-5 (hospitalized but not requiring invasive mechanical ventilation). Patients stratified by age, history of hypertension, and severity are centrally randomized 2:1 (degarelix: placebo). The composite primary endpoint is mortality, ongoing need for hospitalization, or requirement for mechanical ventilation at 15 after randomization. Important secondary endpoints include time to clinical improvement, inpatient mortality, length of hospitalization, duration of mechanical ventilation, time to achieve a normal temperature, and the maximum severity of COVID-19 illness. Exploratory analyses aim to assess the association of cytokines, viral load, and various comorbidities with outcome. In addition, TMPRSS2 expression in target tissue and development of anti-viral antibodies will also be investigated. DISCUSSION: In this trial, we repurpose the FDA approved LHRH antagonist degarelix, commonly used for prostate cancer, to suppress TMPRSS2, a host cell surface protease required for SARS-CoV-2 cell entry. The objective is to determine if temporary androgen suppression with a single dose of degarelix improves the clinical outcomes of patients hospitalized due to COVID-19. TRIAL REGISTRATION: ClinicalTrials.gov NCT04397718. Registered on May 21, 2020.


Assuntos
COVID-19 , Veteranos , Ensaios Clínicos Fase II como Assunto , Hospitalização , Humanos , Masculino , Estudos Multicêntricos como Assunto , Oligopeptídeos , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2 , Resultado do Tratamento
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