Crotty, Thomas B.

PURPOSE: To estimate the efficacy of contralateral prophylactic mastectomy in women with a personal and family history of breast cancer. PATIENTS AND METHODS: We followed the course of 745 women with a first breast cancer and a family history of breast and/or ovarian cancer who underwent contralateral prophylactic mastectomy at the Mayo Clinic between 1960 and 1993. Family history information and cancer follow-up information were obtained from the medical record, a study-specific questionnaire, and telephone follow-up. Life-tables for contralateral breast cancers, which consider age at first breast cancer, current age, and type of family history, were used to calculate the number of breast cancers expected in our cohort had they not had a prophylactic mastectomy. RESULTS: Of the 745 women in our cohort, 388 were premenopausal (age < 50 years) and 357 were post- menopausal. Eight women developed a contralateral breast cancer. Six events were observed among the premenopausal women, compared with 106.2 predicted, resulting in a risk reduction of 94.4% (95% confidence interval [CI], 87.7% to 97.9%). For the 357 postmenopausal women, 50.3 contralateral breast cancers were predicted, whereas only two were observed, representing a 96.0% risk reduction (95% CI, 85.6% to 99.5%). CONCLUSION: The incidence of contralateral breast cancer seems to be reduced significantly after contralateral prophylactic mastectomy in women with a personal and family history of breast cancer.

Endothelial NO synthase (eNOS) is an enzyme responsible for the production of a potent vasodilator and a key regulator of vascular tone, NO. In peripheral arteries, expression of a recombinant eNOS gene increases production of NO in the blood vessel wall. This approach appears to be a promising strategy for gene therapy of cerebrovascular disease. The major objective of the present study was to determine whether a recombinant eNOS gene (AdCMVNOS) can be functionally expressed in cerebral arteries. Replication-defective recombinant adenovirus vectors encoding bovine eNOS and Escherichia coli beta-galactosidase (AdCMVLacZ) genes, driven by the cytomegalovirus promoter, were used for ex vivo gene transfer. Rings of canine basilar artery were incubated with increasing titers of the vectors in MEM. Twenty-four or forty-eight hours after gene transfer, expression and function of AdCMVNOS were evaluated by (1) immunohistochemical staining, (2) isometric tension recording, and (3) cGMP radioimmunoassay. Transfection with AdCMVNOS resulted in the expression of recombinant eNOS protein in the vascular adventitia and endothelium, associated with significantly reduced contractile responses to UTP and enhanced endothelium-dependent relaxation to calcium ionophore A23187. Basal production of cGMP was significantly increased in the transfected vessels. The reduced contractions to UTP with increased cGMP production were reversed by a NOS inhibitor, NG-monomethyl-L-arginine. Contractions to UTP or production of cGMP were not affected in arteries transfected with AdCMVLacZ reporter gene. The results of the present study represent the first successful transfer and functional expression of recombinant eNOS gene in cerebral arteries. Our findings suggest that cerebral arterial tone can be modulated by recombinant eNOS expression in the vessel wall. (Circ Res. 1997;80:327-335.)

Background Adventitial gene transfer may serve as a tool to study vascular biology and may have therapeutic potential. We investigated the hypothesis that adenovirus-mediated transfer of the gene for endothelial nitric oxide synthase (eNOS) to the adventitia would alter vascular reactivity. Methods and Results Rabbit carotid arteries were surgically isolated and adenoviral vectors encoding eNOS (AdeNOS) or β-galactosidase instilled into the periarterial sheath at a concentration of 1×10 10 pfu/mL. Arteries were harvested 4 days later for immunostaining, NOS enzymatic assay, measurement of cGMP, and vasomotor studies. Transgene expression in the adventitia was confirmed by histochemistry for β-galactosidase and immunostaining for eNOS with a monoclonal antibody. Calcium-dependent NOS enzymatic activity and cGMP levels were significantly greater in the AdeNOS-transduced arteries. Maximal contractions to phenylephrine (10 −5 mol/L) were diminished in the AdeNOS-transduced arteries (4.6±0.2 versus 5.6±0.2 g; P <.05), but in the presence of the eNOS inhibitor N G -monomethyl- l -arginine (3×10 −4 mol/L) there was no difference between the two groups (7.1±0.2 versus 7.5±0.3 g; P =NS). Relaxations to calcium ionophore obtained during submaximal contractions to phenylephrine were significantly enhanced in the AdeNOS-transduced arteries (−log EC 50 , 7.77±0.08 versus 7.45±0.07; P <.02). Conclusions We conclude that eNOS gene transfer to the adventitia alters vascular reactivity, as demonstrated by diminished contractile responses to phenylephrine and enhanced relaxations to calcium ionophore. This may represent a therapeutic strategy for vascular diseases characterized by decreased bioavailability of NO.

Abstract To determine the histologic differences in the airways of patients who died from sudden-onset asthma and the more common slow-onset asthma, we studied seven cases of fatal asthma. The numbers of eosinophilsand neutrophils, as well as extracellular deposition of their respective granule contents in the airway mucosa and submucosa, were determined and statistically analyzed. Four of the seven patients had slow-onset asthma attacks in which the time interval between onset of asthma and death was more than 2.5 h. In contrast, three patients had sudden-onset asthma in which the time interval between onset of asthma attack and death was less than 1 h. The four patients with slow-onset fatal asthma had more eosinophils (34.1 ± 6.3 in slow-onset; 9.7 ± 3.5 in sudden-onset; p = 0.002) and fewer neutrophils (4.8 ± 2.0 in slow-onset; 16.8 ± 5.4 in sudden-onset; p = 0.008) in the airway submucosa than did patients with sudden-onset fatal asthma. In addition, within the slow-onset fatal asthma group, eosinophils exceeded neutrophils in the airway submucosa (eosinophils &gt; neutrophils, p = 0.002). By contrast, within the sudden-onset fatal asthma group, neutrophils exceeded eosinophils (neutrophils &gt; eosinophils, p = 0.04). We suggest that sudden-onset fatal asthma is immunohistologically distinct from slow-onset fatal asthma and that it is characterized by a relative paucity of eosinophils in the face of an excess of neutrophils in the airway submucosa. These observations raise the possibility that the mechanism of airway inflammation as well as that of airway narrowing in sudden-onset fatal asthma may be quite distinct from those in slow-onset fatal asthma.

Abstract—The current study was designed to determine the effect of recombinant endothelial nitric oxide synthase (eNOS) gene expression on endothelium-dependent relaxations to bradykinin in isolated canine basilar, coronary, or femoral arteries. Arterial rings were exposed ex vivo (30 minutes at 37°C) to an adenoviral vector encoding either the eNOS gene (AdCMVeNOS) or the β-galactosidase reporter gene (AdCMVβ-Gal). Twenty-four hours after transduction, transgene expression was evident mainly in the adventitia. Expression of recombinant proteins was much higher in basilar arteries than in coronary or femoral arteries. Rings of control, AdCMVβ-Gal, and AdCMVeNOS arteries with and without endothelium were suspended for isometric tension recording. Levels of cGMP were measured by radioimmunoassay. In AdCMVeNOS basilar arteries with endothelium, relaxations to low concentrations of bradykinin (3×10−11to 10−9mol/L) were significantly augmented. In contrast, in coronary and femoral arteries with endothelium, AdCMVeNOS transduction did not affect relaxations to bradykinin. Removal of the endothelium abolished bradykinin-induced relaxations in control and AdCMVβ-Gal basilar arteries. However, in basilar arteries transduced with AdCMVeNOS even when the endothelium was removed, stimulation with bradykinin (3×10−11to 10−9mol/L) caused relaxations as well as increases in cGMP production. The relaxations to bradykinin were completely blocked by an NOS inhibitor,NG-nitro-l-arginine methyl ester. Electron microscopic analysis revealed that recombinant eNOS protein was expressed in fibroblasts of the basilar artery adventitia. These results suggest that genetically modified adventitial fibroblasts may restore production of NO in cerebral arteries without endothelium. Our findings support a novel concept in vascular biology that fibroblasts in the adventitia may play a role in the regulation of vascular tone after successful transfer and expression of recombinant eNOS gene.

Abstract—Macrophage colony stimulating factor (MCSF) is believed to play a key role in one of the earliest events in atherosclerosis, ie, monocyte to macrophage differentiation in the arterial intima. The aim of this study was to examine the biological effects of vascular wall expression of MCSF. A recombinant adenovirus vector encoding human MCSF (AdMCSF) was generated by standard techniques of homologous recombination in 293 cells. The rabbit carotid artery was transduced with AdMCSF. As negative controls, carotid arteries were transduced with either an adenoviral vector encoding β-galactosidase, an adenoviral vector encoding apolipoprotein E, or diluent alone. Intima-media thickness ratio was calculated 5 and 21 days after transduction. The cell type present in intimal infiltrates was analyzed by immunohistochemistry. MCSF expression was demonstrated in the vessel wall of AdMCSF-transduced vessels by reverse transcription–polymerase chain reaction and immunofluorescence. In contrast to control vessels, adenovirus-mediated MCSF expression was associated with an intimal cellular infiltrate consisting of smooth muscle cells and small numbers of macrophages. Whereas the intima-media thickness ratio was greater in AdMCSF-transduced vessels at 5 days, this difference was no longer statistically significant at 21 days. These results suggest that MCSF may play a role in recruitment of monocytes and macrophages to the vessel wall and may contribute to smooth muscle cell proliferation and migration.

OBJECTIVE—To demonstrate the strong association of diabetic mastopathy or sclerosing lymphocytic lobulitis with type 1 diabetes mellitus by studying appropriate control groups and to describe risk factors and natural history of the disorder. RESEARCH DESIGN AND METHODS—This was a retrospective cross-sectional study of four groups of patients conducted at a setting tertiary care medical center. We examined benign breast biopsies (investigator masked to identity) from age-matched patients with types 1 and 2 diabetes, autoimmune thyroid disease, or none of the above disorders for sclerosing lymphocytic lobulitis. Several risk factors proposed for the disorder (age at diagnosis of benign breast disease, duration of diabetes, age at onset of diabetes, prevalence of retinopathy, neuropathy, nephropathy and cheiroarthropathy, glycemic control, parity, oral contraceptive use, menopausal status, or number of breast biopsies) were evaluated, and patients were contacted to describe the natural history of the disorder. RESULTS—Sclerosing lymphocytic lobulitis was identified in 69.7% of the subjects with type 1 diabetes and 1.8% of those with autoimmune thyroid disease diagnosed with benign breast disease at surgery. It did not occur in patients with type 2 diabetes with or without insulin treatment or in control subjects. Only retinopathy and peripheral neuropathy were associated with sclerosing lymphocytic lobulitis. Breast carcinoma or lymphoma did not occur subsequently in any type 1 diabetes patient with or without sclerosing lymphocytic lobulitis. CONCLUSIONS—Sclerosing lymphocytic lobulitis is strongly associated with type 1 diabetes. Retinopathy and neuropathy are associated with the disorder. The risk of malignancy is not increased.