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1.
Eur J Endocrinol ; 187(1): 1-14, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35521709

RESUMO

Context: A sex discordance in COVID exists, with males disproportionately affected. Although sex steroids may play a role in this discordance, no definitive genetic data exist to support androgen-mediated immune suppression neither for viral susceptibility nor for adrenally produced androgens. Objective: The common adrenal-permissive missense-encoding variant HSD3B1(1245C) that enables androgen synthesis from adrenal precursors and that has been linked to suppression of inflammation in severe asthma was investigated in COVID susceptibility and outcomes reported in the UK Biobank. Methods: The UK Biobank is a long-term study with detailed medical information and health outcomes for over 500 000 genotyped individuals. We obtained COVID test results, inpatient hospital records, and death records and tested for associations between COVID susceptibility or outcomes and HSD3B1(1245A/C) genotype. Primary analyses were performed on the UK Biobank Caucasian cohort. The outcomes were identification as a COVID case among all subjects, COVID positivity among COVID-tested subjects, and mortality among subjects identified as COVID cases. Results: Adrenal-permissive HSD3B1(1245C) genotype was associated with identification as a COVID case (odds ratio (OR): 1.11 per C allele, 95% CI: 1.04-1.18, P = 0.0013) and COVID-test positivity (OR: 1.09, 95% CI: 1.02-1.17, P = 0.011) in older (≥70 years of age) women. In women identified as COVID cases, there was a positive linear relationship between age and 1245C allele frequency (P < 0.0001). No associations were found between genotype and mortality or between genotype and circulating sex hormone levels. Conclusion: Our study suggests that a common androgen synthesis variant regulates immune susceptibility to COVID infection in women, with increasingly strong effects as women age.


Assuntos
Androgênios , COVID-19 , Idoso , Alelos , Androgênios/biossíntese , Bancos de Espécimes Biológicos , COVID-19/epidemiologia , COVID-19/genética , Feminino , Humanos , Masculino , Complexos Multienzimáticos/genética , Progesterona Redutase , Esteroide Isomerases , Reino Unido/epidemiologia
2.
Sci Transl Med ; 13(595)2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-34039740

RESUMO

Prostate cancer resistance to next-generation hormonal treatment with enzalutamide is a major problem and eventuates into disease lethality. Biologically active glucocorticoids that stimulate glucocorticoid receptor (GR) have an 11ß-OH moiety, and resistant tumors exhibit loss of 11ß-HSD2, the oxidative (11ß-OH → 11-keto) enzyme that normally inactivates glucocorticoids, allowing elevated tumor glucocorticoids to drive resistance by stimulating GR. Here, we show that up-regulation of hexose-6-phosphate dehydrogenase (H6PD) protein occurs in prostate cancer tissues of men treated with enzalutamide, human-derived cell lines, and patient-derived prostate tissues treated ex vivo with enzalutamide. Genetically silencing H6PD blocks NADPH generation, which inhibits the usual reductive directionality of 11ß-HSD1, to effectively replace 11ß-HSD2 function in human-derived cell line models, suppress the concentration of biologically active glucocorticoids in prostate cancer, and reverse enzalutamide resistance in mouse xenograft models. Similarly, pharmacologic blockade of H6PD with rucaparib normalizes tumor glucocorticoid metabolism in human cell lines and reinstates responsiveness to enzalutamide in mouse xenograft models. Our data show that blockade of H6PD, which is essential for glucocorticoid synthesis in humans, normalizes glucocorticoid metabolism and reverses enzalutamide resistance in mouse xenograft models. We credential H6PD as a pharmacologic vulnerability for treatment of next-generation androgen receptor antagonist-resistant prostate cancer by depleting tumor glucocorticoids.


Assuntos
Desidrogenases de Carboidrato/antagonistas & inibidores , Resistencia a Medicamentos Antineoplásicos , Glucocorticoides , Neoplasias da Próstata/tratamento farmacológico , Glucocorticoides/farmacologia , Humanos , Masculino , Receptores de Glucocorticoides , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Urology ; 134: 192-198, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31542460

RESUMO

OBJECTIVE: To test the hypothesis that transurethral prostate procedures (TUPPs) eliminating tissue result in greater medication discontinuation and lower de novo initiation rates than procedures inducing tissue necrosis. METHODS: Retrospective review of all men undergoing first time TUPPs at a large tertiary center from 2001 to 2016 was completed. Procedure type and urologic medication use before, 3-12 months after, and greater than 12 months after TUPP were analyzed with simple open prostatectomy as a comparator. Tissue-eliminating TUPPs included transurethral resection of the prostate and laser prostatectomy. Tissue-necrosing procedures included microwave therapy (transurethral microwave therapy) and radiofrequency ablation (transurethral needle ablation), which were grouped in analyses. Medication types were 5-alpha reductase inhibitors (5ARI), alpha blockers, anticholinergics, and beta-3 agonists (B3A). RESULTS: A total 5150 TUPPs were analyzed. Preoperative medication use significantly varied across TUPPs for 5ARI (P <.01), alpha-blockers (P .01), and anticholinergics (P .047), but not B3A (P .476). Transurethral resection of the prostate and laser prostatectomy were associated with significantly higher medication discontinuation rates and lower resumption and initiation rates compared to tissue-necrosing procedures. Relative to TUPPs, simple prostatectomy had significantly higher medication discontinuation, as well as the lowest resumption and initiation rates. CONCLUSION: Tissue-eliminating benign prostatic hyperplasia procedures were associated with better medication discontinuation, resumption, and de novo initiation rates compared to tissue-necrosing benign prostatic hyperplasia procedures.


Assuntos
Uso de Medicamentos/estatística & dados numéricos , Micro-Ondas/uso terapêutico , Prostatectomia , Hiperplasia Prostática/terapia , Terapia por Radiofrequência , Ressecção Transuretral da Próstata , Inibidores de 5-alfa Redutase/uso terapêutico , Antagonistas Adrenérgicos alfa/uso terapêutico , Agonistas de Receptores Adrenérgicos beta 3/uso terapêutico , Idoso , Antagonistas Colinérgicos/uso terapêutico , Desprescrições , Humanos , Masculino , Prostatectomia/métodos , Estudos Retrospectivos
4.
Endocrinology ; 160(9): 2180-2188, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31271415

RESUMO

Castration-resistant prostate cancer (PCa) almost invariably occurs after androgen deprivation therapy for metastatic disease and is driven in part by androgen synthesis within the tumor. 3ß-hydroxysteroid dehydrogenase isoenzyme-1 catalyzes the conversion of adrenal precursor steroids into potent androgens essential for PCa progression. A common 1245 A→C missense-encoding single nucleotide polymorphism in HSD3B1 (rs1047303), the gene that encodes this enzyme, leads to a more stable protein that is resistant to degradation and thus increased production of potent androgens from adrenal precursors, facilitating castration-resistant PCa development. Consistent with this mechanism, this adrenal-permissive HSD3B1(1245C) genotype is associated with inferior outcomes after androgen deprivation therapy for advanced PCa, and increased sensitivity to pharmacologic blockade of adrenal precursors in metastatic disease. Herein, we review current knowledge of the mechanisms conferred by HSD3B1 genotype to alter androgen physiology and accelerate development of castration-resistant disease and its associations with clinical PCa outcomes. In light of its effect on steroid physiology, we also discuss its potential associations with non-PCa phenotypes.


Assuntos
Glândulas Suprarrenais/metabolismo , Complexos Multienzimáticos/genética , Progesterona Redutase/genética , Neoplasias de Próstata Resistentes à Castração/genética , Esteroide Isomerases/genética , Androgênios/biossíntese , Desidroepiandrosterona/administração & dosagem , Suplementos Nutricionais , Genótipo , Humanos , Masculino , Complexos Multienzimáticos/fisiologia , Fenótipo , Progesterona Redutase/fisiologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/terapia , Esteroide Isomerases/fisiologia
5.
Int J Mol Sci ; 19(11)2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30469358

RESUMO

G-rich DNA sequences have the potential to fold into non-canonical G-Quadruplex (GQ) structures implicated in aging and human diseases, notably cancers. Because stabilization of GQs at telomeres and oncogene promoters may prevent cancer, there is an interest in developing small molecules that selectively target GQs. Herein, we investigate the interactions of meso-tetrakis-(4-carboxysperminephenyl)porphyrin (TCPPSpm4) and its Zn(II) derivative (ZnTCPPSpm4) with human telomeric DNA (Tel22) via UV-Vis, circular dichroism (CD), and fluorescence spectroscopies, resonance light scattering (RLS), and fluorescence resonance energy transfer (FRET) assays. UV-Vis titrations reveal binding constants of 4.7 × 106 and 1.4 × 107 M-1 and binding stoichiometry of 2⁻4:1 and 10⁻12:1 for TCPPSpm4 and ZnTCPPSpm4, respectively. High stoichiometry is supported by the Job plot data, CD titrations, and RLS data. FRET melting indicates that TCPPSpm4 stabilizes Tel22 by 36 ± 2 °C at 7.5 eq., and that ZnTCPPSpm4 stabilizes Tel22 by 33 ± 2 °C at ~20 eq.; at least 8 eq. of ZnTCPPSpm4 are required to achieve significant stabilization of Tel22, in agreement with its high binding stoichiometry. FRET competition studies show that both porphyrins are mildly selective for human telomeric GQ vs duplex DNA. Spectroscopic studies, combined, point to end-stacking and porphyrin self-association as major binding modes. This work advances our understanding of ligand interactions with GQ DNA.


Assuntos
DNA/química , Quadruplex G , Substâncias Intercalantes/química , Porfirinas/química , Telômero/química , DNA/efeitos dos fármacos , Humanos , Substâncias Intercalantes/farmacologia , Porfirinas/farmacologia , Espermina/química , Telômero/efeitos dos fármacos
6.
Neuromodulation ; 21(7): 665-668, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30092121

RESUMO

INTRODUCTION: Implanted intrathecal drug delivery systems (IDDS) are increasingly used in the treatment of spasticity and in patients with refractory pain. Literature discussing complications associated with intrathecal pump placement is widely available. However, reports of complications following the removal of chronically placed catheters are scarce. We reviewed our series of patients who had surgery to remove the intrathecal catheter. METHODS: Retrospective review was performed for all patients who underwent surgery to remove a catheter linked to an IDDS between 2010 and 2016. Patients older than 18 years were included in final analysis. Demographic (including age at removal, sex, BMI, and comorbidities) and etiologic characteristics (indications of IDDS implant and explant, interval between implant and explant, and concomitant surgery) were analyzed. Simple logistic regression was performed to seek any potential predictor of complications. RESULTS: Fifty-nine patients underwent removal of their intrathecal catheter after variable periods (mean interval of 189 months). On eight occasions, patients developed complications after catheter removal (mean interval between implant and explant was 76 months for these cases). Retained catheter was the cause of complications in half of these occasions. Persistent cerebrospinal fluid leak was the next most common complication, with requirement of an external ventricular drain and lumbar drain to facilitate wound healing on two separate occasions. CONCLUSION: Removal of an intrathecal catheter from IDDS systems may cause complications that in some cases require additional surgery.


Assuntos
Cateteres de Demora/efeitos adversos , Bombas de Infusão Implantáveis/efeitos adversos , Infusão Espinal/efeitos adversos , Espasticidade Muscular/cirurgia , Dor/cirurgia , Adulto , Idoso , Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/etiologia , Dor/etiologia , Pseudomonadaceae , Estudos Retrospectivos
7.
Neuromodulation ; 21(5): 513-519, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28833931

RESUMO

OBJECTIVE: Spinal cord stimulation (SCS) is a safe, reversible surgical treatment for complex regional pain syndrome and failed back surgery syndrome refractory to conventional medical management. Paddle electrodes are routinely used for the permanent implant because of the reduced risk of migration, lower energy requirements, and expanded coverage options. The risks associated with paddle lead removal are not well defined in the literature. METHODS: We retrospectively reviewed the outcomes of all patients at the Cleveland Clinic who underwent removal of SCS paddle electrodes between 2009 and 2016. RESULTS: We identified 68 patients during this interval who had a paddle electrode removed. The most common reason for removal was loss of coverage or effect (75%), followed by infection (13.24%), and the need for magnetic resonance imaging for diagnostic purposes (8.82%). Postoperative complications occurred in eight patients (11.75%), two of which were classified as major (2.94%). One of these patients developed a postoperative cerebrospinal fluid leak, and another suffered a large suprafascial hematoma. Both patients underwent reoperation. Minor complications were reported in six patients (8.82%) and included wound dehiscence, infection, and prolonged ileus in one case. On average, patients who developed complications lost 20 mL more blood during surgery than those who did not develop complications (p = 0.006). CONCLUSION: One of the benefits of SCS therapy is the reversibility of the procedure. However, removal is not without some risk though the overall risk of minor or major complication is low. Patients who are considering removal should be counseled appropriately. Prophylactic removal is not recommended. However, when removal is needed, surgeons and pain specialists must be familiar with these complications and their management.


Assuntos
Síndromes da Dor Regional Complexa/etiologia , Eletrodos Implantados/efeitos adversos , Síndrome Pós-Laminectomia/etiologia , Complicações Pós-Operatórias/etiologia , Traumatismos da Medula Espinal/etiologia , Estimulação da Medula Espinal/efeitos adversos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Reoperação , Estudos Retrospectivos , Medula Espinal , Adulto Jovem
8.
Neuromodulation ; 20(5): 444-449, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28466562

RESUMO

INTRODUCTION: Deep brain stimulation (DBS) is a well-recognized treatment for patients with movement disorders and other neurological diseases. The implantable pulse generator (IPG) is a fundamental component of the DBS system. Although IPG implantation and replacement surgeries are comparatively minor procedures relative to the brain lead insertion, patients often require multiple IPG replacements during their lifetime with each operation carrying a small but possibly cumulative risk of complications. To better educate our patients and improve surgical outcomes, we reviewed our series of patients at our institution. METHODS: Using electronic health record data, we retrospectively reviewed all initial and subsequent IPG surgeries from patients who underwent at least one IPG surgery between the years of 2010 and 2015 at the Cleveland Clinic main campus. We calculated infection rates for initial IPG implantation surgeries and the infection rate for subsequent replacements. Fisher's exact tests were used to evaluate the chance of an infection between the initial implantation and replacement. Fisher's exact tests and simple logistic regression analyses were used to determine the predictive ability of selected demographic and clinical variables RESULTS: Our final sample included 697 patients and 1537 surgeries. For all patients, the infection rate at the first surgery was 2.01%; at the second surgery, it was 0.44%; and at the third surgery, it was 1.83%. When considering only patients that underwent at least three replacement surgeries (n = 114) the infection rate did not change in a significant manner with subsequent interventions compared to the first replacement. No other variable of interest was a significant predictor of infection. CONCLUSION: We did not find increasing rates of infection with subsequent IPG replacement procedures.


Assuntos
Estimulação Encefálica Profunda/instrumentação , Estimulação Encefálica Profunda/tendências , Eletrodos Implantados/tendências , Reoperação/instrumentação , Reoperação/tendências , Infecção da Ferida Cirúrgica/cirurgia , Idoso , Idoso de 80 Anos ou mais , Estimulação Encefálica Profunda/efeitos adversos , Eletrodos Implantados/efeitos adversos , Eletrodos Implantados/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação/efeitos adversos , Estudos Retrospectivos , Infecção da Ferida Cirúrgica/diagnóstico , Infecção da Ferida Cirúrgica/etiologia
9.
J Neurosurg Spine ; 26(5): 628-637, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28291408

RESUMO

OBJECTIVE Improvements in imaging technology have steadily advanced surgical approaches. Within the field of spine surgery, assistance from the O-arm Multidimensional Surgical Imaging System has been established to yield superior accuracy of pedicle screw insertion compared with freehand and fluoroscopic approaches. Despite this evidence, no studies have investigated the clinical relevance associated with increased accuracy. Accordingly, the objective of this study was to investigate the clinical outcomes following thoracolumbar spinal fusion associated with O-arm-assisted navigation. The authors hypothesized that increased accuracy achieved with O-arm-assisted navigation decreases the rate of reoperation secondary to reduced hardware failure and screw misplacement. METHODS A consecutive retrospective review of all patients who underwent open thoracolumbar spinal fusion at a single tertiary-care institution between December 2012 and December 2014 was conducted. Outcomes assessed included operative time, length of hospital stay, and rates of readmission and reoperation. Mixed-effects Cox proportional hazards modeling, with surgeon as a random effect, was used to investigate the association between O-arm-assisted navigation and postoperative outcomes. RESULTS Among 1208 procedures, 614 were performed with O-arm-assisted navigation, 356 using freehand techniques, and 238 using fluoroscopic guidance. The most common indication for surgery was spondylolisthesis (56.2%), and most patients underwent a posterolateral fusion only (59.4%). Although O-arm procedures involved more vertebral levels compared with the combined freehand/fluoroscopy cohort (4.79 vs 4.26 vertebral levels; p < 0.01), no significant differences in operative time were observed (4.40 vs 4.30 hours; p = 0.38). Patients who underwent an O-arm procedure experienced shorter hospital stays (4.72 vs 5.43 days; p < 0.01). O-arm-assisted navigation trended toward predicting decreased risk of spine-related readmission (0.8% vs 2.2%, risk ratio [RR] 0.37; p = 0.05) and overall readmissions (4.9% vs 7.4%, RR 0.66; p = 0.07). The O-arm was significantly associated with decreased risk of reoperation for hardware failure (2.9% vs 5.9%, RR 0.50; p = 0.01), screw misplacement (1.6% vs 4.2%, RR 0.39; p < 0.01), and all-cause reoperation (5.2% vs 10.9%, RR 0.48; p < 0.01). Mixed-effects Cox proportional hazards modeling revealed that O-arm-assisted navigation was a significant predictor of decreased risk of reoperation (HR 0.49; p < 0.01). The protective effect of O-arm-assisted navigation against reoperation was durable in subset analysis of procedures involving < 5 vertebral levels (HR 0.44; p = 0.01) and ≥ 5 levels (HR 0.48; p = 0.03). Further subset analysis demonstrated that O-arm-assisted navigation predicted decreased risk of reoperation among patients undergoing posterolateral fusion only (HR 0.39; p < 0.01) and anterior lumbar interbody fusion (HR 0.22; p = 0.03), but not posterior/transforaminal lumbar interbody fusion. CONCLUSIONS To the authors' knowledge, the present study is the first to investigate clinical outcomes associated with O-arm-assisted navigation following thoracolumbar spinal fusion. O-arm-assisted navigation decreased the risk of reoperation to less than half the risk associated with freehand and fluoroscopic approaches. Future randomized controlled trials to corroborate the findings of the present study are warranted.


Assuntos
Imageamento Tridimensional , Vértebras Lombares/cirurgia , Fusão Vertebral , Cirurgia Assistida por Computador , Vértebras Torácicas/cirurgia , Tomografia Computadorizada por Raios X , Parafusos Ósseos , Feminino , Fluoroscopia , Humanos , Estimativa de Kaplan-Meier , Tempo de Internação , Masculino , Erros Médicos , Pessoa de Meia-Idade , Duração da Cirurgia , Readmissão do Paciente , Falha de Prótese , Reoperação , Estudos Retrospectivos , Resultado do Tratamento
10.
J Biol Inorg Chem ; 21(2): 227-39, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26748794

RESUMO

G-quadruplexes are non-canonical DNA structures formed by guanine-rich DNA sequences that are implicated in cancer and aging. Understanding how small molecule ligands interact with quadruplexes is essential both to the development of novel anticancer therapeutics and to the design of new quadruplex-selective probes needed for elucidation of quadruplex biological functions. In this work, UV-visible, fluorescence, and circular dichroism spectroscopies, fluorescence resonance energy transfer (FRET) melting assays, and resonance light scattering were used to investigate how the Pt(II) and Pd(II) derivatives of the well-studied 5,10,15,20-tetrakis(N-methyl-4-pyridyl)porphyrin (TMPyP4) interact with quadruplexes formed by the human telomeric DNA, Tel22, and by the G-rich sequences from oncogene promoters. Our results suggest that Pt- and PdTMPyP4 interact with Tel22 via efficient π-π stacking with a binding affinity of 10(6)-10(7) M(-1). Under porphyrin excess, PtTMPyP4 aggregates using Tel22 as a template; the aggregates reach maximum size at [PtTMPyP4]/[Tel22] ~8 and dissolve at [PtTMPyP4]/[Tel22] ≤ 2. FRET assays reveal that both porphyrins are excellent stabilizers of human telomeric DNA, with stabilization temperature of 30.7 ± 0.6 °C for PtTMPyP4 and 30.9 ± 0.4 °C for PdTMPyP4 at [PtTMPyP4]/[Tel22] = 2 in K(+) buffer, values significantly higher as compared to those for TMPyP4. The porphyrins display modest selectivity for quadruplex vs. duplex DNA, with selectivity ratios of 150 and 330 for Pt- and PdTMPyP4, respectively. This selectivity was confirmed by observed 'light switch' effect: fluorescence of PtTMPyP4 increases significantly in the presence of a variety of DNA secondary structures, yet the strongest effect is produced by quadruplex DNA.


Assuntos
Quadruplex G , Paládio/química , Platina/química , Porfirinas/química , Espalhamento de Radiação , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
11.
FEBS J ; 281(7): 1726-37, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24494857

RESUMO

Guanine quadruplexes (GQ) are four-stranded DNA structures formed by guanine-rich DNA sequences. The formation of GQs inhibits cancer cell growth, although the detection of GQs in vivo has proven difficult, in part because of their structural diversity. The development of GQ-selective fluorescent reporters would enhance our ability to quantify the number and location of GQs, ultimately advancing biological studies of quadruplex relevance and function. N-methylmesoporphyrin IX (NMM) interacts selectively with parallel-stranded GQs; in addition, its fluorescence is sensitive to the presence of DNA, making this ligand a possible candidate for a quadruplex probe. In the present study, we investigated the effect of DNA secondary structure on NMM fluorescence. We found that NMM fluorescence increases by about 60-fold in the presence of parallel-stranded GQs and by about 40-fold in the presence of hybrid GQs. Antiparallel GQs lead to lower than 10-fold increases in NMM fluorescence. Single-stranded DNA, duplex, or i-motif, induce no change in NMM fluorescence. We conclude that NMM shows promise as a 'turn-on' fluorescent probe for detecting quadruplex structures, as well as for differentiating them on the basis of strand orientation.


Assuntos
Corantes Fluorescentes/química , Quadruplex G , Mesoporfirinas/química , DNA de Cadeia Simples/química , Fluorescência
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