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S D Spivack

Publications and source records attributed to S D Spivack.

8 recordsLinked to original sources

Estrogen receptor alpha increases basal and cigarette smoke extract-induced expression of CYP1A1 and CYP1B1, but not GSTP1, in normal human bronchial epithelial cells.

Gender-specific estrogen receptor alpha (ERalpha) expression may plausibly influence lung carcinogenesis in females. Initial genome-wide microarray studies confirmed that carcinogen metabolism genes (CYP1A1, CYP1B1) were those most responsive to cigarette smoke extract (CSE) in normal bronchial epithelial (NHBE) cells. These two genes encoding phase I bioactivating enzymes and the GSTP1 gene encoding a phase II deactivating enzyme were then tested for induction by ERalpha. NHBE cells (native ERalpha-) were transfected with wild-type ERalpha-adenoviral constructs, and then exposed to CSE, 17beta-estradiol (E2), and/or the ERalpha inhibitor, ICI 182,780. The expression levels of CYP1A1, CYP1B1, and GSTP1 were then determined by RNA-specific quantitative RT-PCR and immunoassay. ERalpha increased the basal expression of CYP1B1 4.04-fold (P < 0.01) at the mRNA level and 6.5-fold at the protein level. ERalpha also increased the CSE-induced mRNA expression of CYP1B1 2.26-fold (P < 0.01), but not the protein expression. ERalpha did not alter the CYP1A1 mRNA levels, but did increase protein expression 2.0-fold (P < 0.01) on CSE exposure, and 6.2-fold (P < 0.01) upon E2 exposure. These effects could be inhibited by ICI 182,780. ERalpha did not alter the expression of GSTP1. Chromatin immunoprecipitation assay (ChIP) assay confirmed ERalpha binding to CYP1B1 promoter near the transcription start site. These results suggest that ERalpha regulates the CYP1B1 expression at a transcriptional level, and CYP1A1 expression at a translational level. These data raise the possibility that inter-gender differences in expression of ERalpha that are known to exist in human lung may contribute to inter-individual expression differences in CYP1A1 and CYP1B1, and to differences in carcinogen metabolism and mutation.

Adenoviridae↗

CYP1B1 expression in human lung.

Cytochrome P450 1B1 is a recently recognized phase I bioactivating enzyme with high affinity for both inhaled tobacco carcinogens and 17beta-estradiol. We evaluated the human lung expression of this multifunctional member of the P450 superfamily across 16 individuals. Expression of CYP1B1 was evaluated by qualitative reverse transcription-polymerase chain reaction and Western immunoblots performed on human tumor and nontumor lung tissue. Expression at both mRNA and protein levels was then correlated with smoking history, plasma biomarkers of tobacco exposure (nicotine and cotinine), gender, and tumor histology. CYP1B1 mRNA and protein were detected in 94 and 100% of individuals, respectively. Multivariate analysis confirmed that there were more subjects displaying CYP1B1 mRNA expression in tumor than nontumor tissue (p = 0.0003). Correlation of CYP1B1 protein with plasma cotinine levels was statistically marginal (p = 0.027). Self-reported smoking history, gender, and tumor histology did not correlate with gene expression in the multivariate model. After multivariate modeling for confounding factors, the expression patterns of 5 of 16 individuals appeared to differ from the group as a whole for mRNA and/or protein. We conclude that CYP1B1 is commonly expressed in human lung and hypothesize that it may be an important phase I enzyme with respect to human lung carcinogen metabolism, warranting an understanding of regulatory control and coding region polymorphisms.

Aryl Hydrocarbon Hydroxylases↗

Acute eosinophilic pneumonia associated with shock.

OBJECTIVE: To describe an unusual case of acute eosinophilic pneumonia (AEP) associated with hemodynamic instability. DESIGN: Case report, clinical. SETTINGS: Tertiary care intensive care unit (ICU). PATIENT: A single patient admitted to the ICU. INTERVENTIONS: Intravenous corticosteroids. MEASUREMENTS AND MAIN RESULTS: Resolution of distributive shock and respiratory failure. CONCLUSIONS: AEP with respiratory failure was first reported in 1989 as a distinct clinical entity. Patients with this variant of eosinophilic lung disease develop acute hypoxemic respiratory failure with a rapid response to treatment with corticosteroids, The characteristic feature of this syndrome is a predominance of eosinophils found in bronchoalveolar lavage fluid and lung biopsy. Despite the increasing number of reported cases, to our knowledge, distributive shock has not been reported as a feature of AEP. We report a unique case of AEP associated with shock and review the pertinent literature.

Acute Disease↗

The molecular epidemiology of lung cancer.

One in ten tobacco smokers develops bronchogenic carcinoma over a lifetime. The study of susceptibility of an individual and a population to lung cancer traditionally has been limited to the study of tobacco smoke dose and family history of cancer. New insights into lung carcinogenesis have made the study of molecular markers of risk possible in human populations in the emerging field of molecular epidemiology. This review summarizes data addressing the relationships of human lung cancer to polymorphisms of phase I procarcinogen-activating and phase II-deactivating enzymes and intermediate biomarkers of DNA mutation, such as DNA adducts, oncogene and tumor suppressor gene mutation, and polymorphisms. These parameters are reviewed as they relate to tobacco smoke exposure, procarcinogen metabolizing polymorphisms, and the presence of lung cancer. Problem areas in biomarker validation, such as cross-sectional data interpretation; tissue source, race, statistical power, and ethical implications are addressed.

Biomarkers, Tumor↗

Preoperative prediction of postoperative respiratory outcome. Coronary artery bypass grafting.

OBJECTIVE: The hypothesis that traditionally defined preoperative risk factors predict prolonged mechanical ventilation after coronary artery bypass graft surgery (CABG) was tested in our cohort. The predictive power of these factors was quantified, and specific patient subsets destined for prolonged mechanical ventilation after CABG surgery were defined. DESIGN: Five hundred thirteen consecutive patients undergoing CABG were prospectively evaluated. Preoperative pulmonary evaluation included clinical historic data, standard spirometry, and arterial blood gas. Preoperative cardiac parameters included clinical parameters and left ventricular function assessment. Nonthoracic organ (renal, endocrine, pancreas, liver) function was assessed. SETTING: University-based, tertiary referral center. INTERVENTIONS: None (observational only). OUTCOMES MEASURED: Duration of mechanical ventilation, duration of surgical ICU stay, and mortality. RESULTS: Multivariate regression analyses revealed that for the patient undergoing routine elective surgery and the patient undergoing urgent surgery, prolonged mechanical ventilation and death were rare events (8.3% and 2.0%, respectively). The combination of reduced left ventricular ejection fraction and the presence of selected preexisting comorbid conditions (clinical congestive heart failure, angina, current smoking, diabetes) served as modest risk factors for prolonged mechanical ventilation; their absence strongly predicted an uncomplicated postoperative respiratory course. No pulmonary diagnosis, mechanical lung function, or blood gas parameter substantially contributed to predicting adverse outcome. Classification and regression tree subgroup analysis refined specific factors important in specific subgroups. CONCLUSION: With the exception of left ventricular ejection fraction, no preoperative factors emerge as good predictors across all subgroups. This series suggests that pulmonary diagnosis, lung mechanics, and blood gas parameters do not offer the clinician global rules in predicting postoperative respiratory outcome, nor should they be used as exclusion crteria for CABG surgery.

Aged↗