代谢综合征与乳腺癌

研究显示,代谢综合征可增加女性乳腺癌的患病风险,在绝经后妇女中表现更明显.这种作用可能通过胰岛素抵抗影响雌激素和性激素结合球蛋白水平、高胰岛素血症的直接或间接作用以及脂肪因子水平异常等机制实现.因此,对于我国乳腺癌发病率可能随代谢综合征人群不断扩大而上升的趋势应予以足够重视.     

腹内脂肪与胰岛素抵抗

腹内脂肪与胰岛素抵抗的关系密切,它在形态、脂解等方面不同于皮下脂肪。脂肪细胞分泌的细胞因子在胰岛素抵抗的发生发展中有着重要的作用。明确腹内脂肪致胰岛素抵抗的机制有益于代谢综合征的防治。     

腹内脂肪与胰岛素抵抗

腹内脂肪与胰岛素抵抗的关系密切,它在形态、脂解等方面不同于皮下脂肪.脂肪细胞分泌的细胞因子在胰岛素抵抗的发生发展中有着重要的作用.明确腹内脂肪致胰岛素抵抗的机制有益于代谢综合征的防治.     

代谢综合征与遗传

代谢综合征是指一组与糖尿病和心血管疾病发病风险增加相关联的症候群。不同学术组织对于代谢综合征的定义有所不同,但其基本要素主要包括胰岛素抵抗、异常葡萄糖代谢、高血压、致动脉粥样硬化的脂代谢紊乱、肥胖等。家系研究以及双生子研究显示遗传因素在代谢综合征中各个组分中都扮演着不同程度的重要角色。在代谢综合征患者中有一部分是由于单基因突变所导致的特殊类型的代谢综合征,这些患者的共同特点包括脂质萎缩以及严重的胰岛素抵抗等。导致这些特殊类型代谢综合征发生的单基因突变包括AKT2R274H,PPARs家族的PPARγF388L基因突变、PPARγArg397Cys基因突变、PPARγP467L与PPARγV290M基因突变,核纤层蛋白A／C基因的lamin A G602S突变、LMNA R482W突变等。此外,由于对代谢综合征的定义和理解不同,在代谢综合征的遗传学研究中造成了很大困难。     

代谢综合征发病机制研究进展

随着经济的发展和人们生活水平的提高以及生活方式的改变,代谢综合征（metabolic syndrome,MS）的患病率逐年上升。代谢综合征是一种涉及多种代谢异常、与心血管病紧密联系的疾病状态。肥胖或超重、糖调节异常或糖尿病、高血压和高血脂是MS的重要组成元素。代谢综合征一直是人们关注的热点,但截止目前确切机制仍不明确。主要围绕肥胖与胰岛素抵抗展开研究,特别是在脂毒性和脂肪分泌因子的调控以及各种炎性因子的影响方面取得了一些进展。     

代谢综合征：动脉粥样硬化危险因素的聚集

代谢综合征是动脉粥样硬化危险因素的聚集状态,包括肥胖、高血压、血糖异常、血脂紊乱等,共同的病理基础是肥胖和胰岛素抵抗。高胰岛素血症、脂肪因子、高血糖、血脂异常和高血压导致内皮细胞损伤和血管炎症,促进动脉粥样硬化发展。提高对代谢综合征的认识有助于从整体观念出发防治肥胖带来的相关疾病。     

2型糖尿病大血管病变机理和糖尿病治疗

2型糖尿病大血管病变与代谢综合征密切相关.现代医学认为两者的根本原因是胰岛素抵抗,导致糖耐量下降,血脂紊乱,高胰岛素血症,高血压和高凝状态等.从系统论的观点阐述了代谢综合征的相互关系和2型糖尿病大血管病变发病机理,并进一步从该观点阐明2型糖尿病的防治策略.     

代谢综合征:动脉粥样硬化危险因素的聚集

代谢综合征是动脉粥样硬化危险因素的聚集状态,包括肥胖、高血压、血糖异常、血脂紊乱等,共同的病理基础是肥胖和胰岛素抵抗.高胰岛素血症、脂肪因子、高血糖、血脂异常和高血压导致内皮细胞损伤和血管炎症,促进动脉粥样硬化发展.提高对代谢综合征的认识有助于从整体观念出发防治肥胖带来的相关疾病.     

一把双刃剑:胰岛素样生长因子-Ⅰ的双向作用

胰岛素样生长因子-Ⅰ(insulin-like growth factor-Ⅰ,IGF-Ⅰ)作为一种有丝分裂原,一方面可以促进生长、减少胰岛素抵抗、治疗生长激素不敏感综合征、心衰及肾衰等;另一方面,高水平的IGF-Ⅰ却又与前列腺癌、乳腺癌及结肠直肠癌等相关.同一种活性物质却具有差异如此大的作用,本文将综述并从哲学的思维和视角认识IGF-Ⅰ的双向作用.     

一把双刃剑：胰岛素样生长因子-I的双向作用

胰岛素样生长因子-I（insulin--likegrowthfactor—I,IGF—I）作为一种有丝分裂原,一方面可以促进生长、减少胰岛素抵抗、治疗生长激素不敏感综合征、心衰及肾衰等;另一方面,高水平的IGF—I却又与前列腺癌、乳腺癌及结肠直肠癌等相关。同一种活性物质却具有差异如此大的作用,本文将综述并从哲学的思雏和视角认识IGF—I的双向作用。     

Cowden Syndrome

Cowden syndrome is an autosomal dominant inherited cancer syndrome characterized by multiple hamartomas which may develop in any organ. Mucocutaneous papillomas and trichilemmomas are hallmarks of the syndrome. Affected individuals are at high risk of developing both benign and malignant disease of the thyroid and breast. Epithelial thyroid carcinoma occurs in 3–10% of affected individuals while women have a 25–50% lifetime risk of developing adenocarcinoma of the breast. Because of the cancer risk, it is imperative that health care providers recognize Cowden syndrome. The susceptibility gene has been localized to 10q22-23 and preliminary studies demonstrate no genetic heterogeneity.     

Clinical Characterization and Risk Profile of Individuals Seeking Genetic Counseling for Hereditary Breast Cancer in Brazil

Hereditary breast cancer (HBC) accounts for 5–10% of breast cancer cases and it significantly increases the lifetime risk of cancer. Our objective was to evaluate the sociodemographic variables, family history of cancer, breast cancer (BC) screening practices and the risk profile of cancer affected or asymptomatic at-risk women that undergo genetic counseling for hereditary breast cancer in public Brazilian cancer genetics services. Estimated lifetime risk of BC was calculated for asymptomatic women using the Gail and Claus models. The majority of women showed a moderate lifetime risk of developing BC, with an average risk of 19.7% and 19.9% by the Gail and Claus models, respectively. The average prior probability of carrying a BRCA1/2 gene mutation was 16.7% and overall only 32% fulfilled criteria for a hereditary breast cancer syndrome as assessed by family history. We conclude that a significant number of individuals at high-risk for HBC syndromes may not have access to the benefits of cancer genetic counseling in these centers. Contributing factors may include insufficient training of healthcare professionals, disinformation of cancer patients; difficult access to genetic testing and/or resistance in seeking such services. The identification and understanding of these barriers is essential to develop specific strategies to effectively achieve cancer risk reduction in this and other countries were clinical cancer genetics is not yet fully established.     

Association between socioeconomic status and metabolic syndrome in women: testing the reserve capacity model

OBJECTIVE: Low socioeconomic status (SES) environments may impede the development of a bank of resources, labeled reserve capacity, and may also be stressful, thereby depleting available reserves. In consequence, lower SES persons may experience more negative emotions, leading to adverse health consequences. The authors tested the reserve capacity model in relation to the metabolic syndrome. DESIGN: There were 401 initially healthy women who followed longitudinally for 12 years. Self-reported characteristics, stressors, and cardiovascular risk factors were measured repeatedly. Structural equation modeling was used to evaluate hypothesized relationships. MAIN OUTCOME MEASURE: Metabolic syndrome factor. RESULTS: Confirmatory factor analysis verified reserve capacity as the aggregate of optimism, self-esteem, and social support, and negative emotion as the aggregate of depressive symptoms, anger, and tension. Structural equation modeling showed two pathways to the metabolic syndrome factor, (chi2(59) = 111.729, p < .0001 chi2/df = 1.894; CFI = .956; RMSEA = .047): direct from low SES to the metabolic syndrome factor (B = -0.19, t = -3.24, p = .001); and indirect, from low SES to low reserve capacity to high negative emotions to the metabolic syndrome factor (B = -0.024, t = -2.05, p = .04). CONCLUSION: Low SES may increase risk for metabolic syndrome, in part, through reserve capacity and negative emotions.     

Exploring Emotion-Regulation and Autonomic Physiology in Metastatic Breast Cancer Patients: Repression, Suppression, and Restraint of Hostility

We examined relationships between three emotion-regulation constructs and autonomic physiology in metastatic breast cancer patients (N = 31). Autonomic measures are not often studied in breast cancer patients and may provide evidence of an increase in allostatic load. Patients included participated as part of a larger clinical trial of supportive-expressive group therapy. Systolic and diastolic blood pressure and heart rate were assessed at a semi-annual follow-up. We averaged 3 resting assessments and used measures of Repression, Suppression, Restraint of Hostility, and Body Mass Index as predictors of autonomic response. We found that higher repression was significantly associated with higher diastolic blood pressure, while higher restraint of hostility was significantly associated with higher systolic blood pressure. A repressive emotion regulation style may be a risk factor for higher sympathetic activation possibly increasing allostatic load, while restraint of hostility may be a protective factor for women with metastatic breast cancer.     

Participation in Breast Cancer Genetic Counseling: The Influence of Educational Level, Ethnic Background, and Risk Perception

Genetic counseling has been suggested as a means of providing information and support to women with a family history of breast cancer. Yet women who undergo cancer genetic counseling in the United States generally consist of only a subset of those at risk, namely well-educated, upper-middle class, European American and Jewish women. We report outcomes from a study that provided a unique opportunity to determine whether women of African American, European American, Native American, or Ashkenazi Jewish ancestry have varying interest in having cancer genetic counseling. The study offered a genetic counseling session to 97 women with a family history of breast cancer who were participating in a larger interview study designed to assess attitudes toward genetic testing for breast cancer. The study offered genetic counseling free of charge to all study participants with a family history of breast cancer, removing the potential barriers of cost, the need for a physician referral, and lack of awareness of genetic counseling. Fifty women out of the 97 women offered genetic counseling (52%) accepted the offer by completing a session. Those who accepted genetic counseling had a higher educational level, a higher perceived risk of breast cancer, and were more likely to expect a positive BRCA1 or BRCA2 genetic test if they were to undergo genetic testing. When controlling for education level, there was no correlation between the participants' ethnic background and acceptance of a genetic counseling session. Outreach efforts to minority populations may increase awareness of the availability of genetic counseling and may facilitate participation by such populations.     

Breast Cancer in Men: Emasculation by Association?

The occurrence of breast cancer in men is rare in comparison to women. Public knowledge that men can get breast cancer and of male breast self-examination are lacking. Research in the course and treatment of breast cancer in men is needed. Men generally present in more advanced stages of breast cancer than women, and have a poorer prognosis. In this article, the epidemiology, common symptoms, diagnostic methods, and current treatment of breast cancer in men are described. Gender differences in presentation and course of illness are discussed. Additionally, the psychological implications of breast cancer for male gender roles and masculine identity are explored. Directions for further investigation are given. Treatment providers are encouraged to educate themselves and their male patients on breast cancer in men and male breast examination techniques so that this disease may be identified earlier in its course and survival rates improved.     

对保乳手术及预防性乳腺切除术的思考

鉴于对乳腺癌是全身性疾病的认识,为提高术后生存质量,目前乳腺癌治疗中保乳手术日益受到重视.而为了阻断高危险性的乳腺向乳腺癌发展,预防性乳房切除术也正在被患者接受.保留乳腺与预防性切除乳腺的医学实践反映了目前人们对乳腺癌的深层认识,值得深入思考.     

Cancer Genetics Service Interest in Women with a Limited Family History of Breast Cancer

Women with a limited family history of breast cancer may be interested in cancer genetics information although their objective risk of breast cancer may not indicate routine referral to cancer genetics services. This study examined factors related to interest and use of cancer genetics services in a community sample of women with a limited family history of breast cancer (N = 187) who had no previous contact with cancer genetics services. Participants provided demographic information and ratings of perceived risk, cancer distress, attitudes, and intentions to initiate cancer genetics services. Participants were given information about a cancer genetics clinic that served women having concerns about their breast cancer risk. Women were contacted within 6 weeks and 8 months following their study appointment. Six weeks following their study appointment, 25% of women had initiated cancer genetics services. Eight months following their study appointment, 18% of women reported having completed a cancer genetics service appointment. Baseline intentions independently predicted both initiation at 6 weeks and appointment at 8 months. Cancer distress was positively associated with cancer genetics service initiation and appointment. Results suggest that some women with a limited family history of breast cancer are interested in seeking out cancer genetics information. Women with a limited family history of breast cancer may benefit from the availability of cancer genetics information provided through primary healthcare settings.     

Genes and family environment in familial clustering of cancer

Familial clustering of a disease is defined as the occurrence of the disease within some families in excess of what would be expected from the occurrence in the population. It has been demonstrated for several cancer types, ranging from rare cancers as the adenomatosis-coli-associated colon cancer or the Li-Fraumeni syndrome to more common cancers as breast cancer and colon cancer. Familial clustering, however, is merely an epidemiological pattern, and it does not tell whether genetic or environmental causes or both in combination are responsible for the familial clustering. Familial clustering may be due to genetic predisposition to the disease, but exposure to environmental factors — shared by members of some families, but not by members of other families — may also cause familial clustering and hence mimic genetic inheritance in the study of nuclear families. Based on assumptions regarding the individual steps in the biological process starting with exposure to carcinogens and ending with death from disseminated cancer we suggest that genetic and environmental factors may both be involved in most of these steps. The present paper focuses on research methodologies necessary to discriminate between the effect of genes and family environment in the development of cancer.     

Factors Influencing Perceptions of Breast Cancer Genetic Counseling among Women in an Urban Health Care System

The study assessed perceptions of breast cancer genetic counseling. Focus groups were conducted with twenty women (ages < = 50 years) in a Midwestern, urban health system identified as at above average risk of developing hereditary breast cancer and referred for breast cancer genetic counseling following mammography. All participants associated the words “breast cancer” with fear. African American women who received breast cancer genetic counseling may have channeled their fear into increased vigilance related to breast health. African American women who did not receive breast cancer genetic counseling were most knowledgeable about it. In contrast, Caucasian women who did not receive it reported uncertainty about the role of genetic counseling and testing in assessing breast cancer risk, mistrust in medical professionals, and lack of trust in the accuracy of genetic tests. The results could be used to help develop interventions to improve informed decision-making regarding breast cancer genetic counseling.