Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Breast Cancer”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8Linked to original sources

Prophylaxis approach to a-symptomatic post-menopausal women: breast cancer.

Breast cancer is the most common cancer of women worldwide. Its frequency increases throughout the female lifespan. Epidemiological research has clearly identified important reproductive risk factors for breast cancer, including age at menarche, age at menopause, age at first-term pregnancy and nulliparity, which provide important clues to the hormonal origin of this disease. The widespread use of exogenous sex steroids as contraceptive agents and as hormonal replacement therapy has been a source of concern and generates discussion about their effects on breast health. Lifestyle changes, exercise or diet could play a role in primary prevention of breast cancer. Regular exercise, ingestion of adequate amounts of fruit and vegetables, limiting alcohol consumption, avoidance of obesity in post-menopausal women, and perhaps the use of olive oil, may all have a protective effect and should be considered by women. There is insufficient scientific evidence of the role played by phyto-oestrogens on breast cancer risk. Other preventive measures that include the use of drugs such as statins or aspirin should not be recommended until we have more information about their effects on the breast. Especially for high-risk women, all the aforementioned measures may be not enough, and chemo-prevention should be considered. The use of selective oestrogen receptor modulators (SERMs) to reduce breast cancer risk is still being evaluated. Tamoxifen was the first SERM approved for the reduction of breast cancer incidence in women at high risk. However its use has limitations, due to significant side effects. Raloxifene has been approved for the prevention and treatment of post-menopausal osteoporosis and has provided excellent indications of breast cancer risk reduction, with a more favourable profile than tamoxifen.

Anticarcinogenic Agents↗

Women's psychological reactions to breast cancer.

Breast cancer is the cancer most studied in terms of psychological and psychosocial aspects because of the high prevalence and mortality of the disease and the psychological effects of surgery on an organ rich in meaning. The diagnosis of breast cancer, treatment, and treatment sequelae are major stressors for any woman; however, the psychological impact of the diagnosis and women's emotional responses vary considerably depending on medical parameters of the disease, the patient's psychological make-up and coping abilities, and the availability of emotional and financial support. We document the experience of breast cancer at all phases of the disease for a majority of psychologically healthy women and describe the emotional responses of women who are at high genetic risk of developing breast cancer. Having a comprehensive understanding of psychologically healthy women's reactions to breast cancer is necessary as we attempt to define standards of care and treatment guidelines for both psychologically healthy women with breast cancer and for those with psychiatric disorders that antedate or complicate breast cancer treatment.

Adaptation, Psychological↗

Does lack of tocopherols and tocotrienols put women at increased risk of breast cancer?

Breast cancer is the leading site of new cancers in women and the second leading cause (after lung cancer) of cancer mortality in women. Observational studies that have collected data for dietary exposure to alpha-tocopherol with or without the other related tocopherols and tocotrienols have suggested that vitamin E from dietary sources may provide women with modest protection from breast cancer. However, there is no evidence that vitamin E supplements confer any protection whatever against breast cancer. Observational studies that have assessed exposure to vitamin E by plasma or adipose tissue concentrations of alpha-tocopherol have failed to provide consistent support for the idea that alpha-tocopherol provides any protection against breast cancer. In addition, evidence from studies in experimental animals suggest that alpha-tocopherol supplementation alone has little effect on mammary tumors. In contrast, studies in breast cancer cells indicate that alpha- gamma-, and delta-tocotrienol, and to a lesser extent delta-tocopherol, have potent antiproliferative and proapoptotic effects that would be expected to reduce risk of breast cancer. Many vegetable sources of alpha-tocopherol also contain other tocopherols or tocotrienols. Thus, it seems plausible that the modest protection from breast cancer associated with dietary vitamin E may be due to the effects of the other tocopherols and the tocotrienols in the diet. Additional studies will be required to determine whether this may be the case, and to identify the most active tocopherol/tocotrienol.

Journal Article↗

PDZ-binding kinase/T-LAK cell-originated protein kinase, a putative cancer/testis antigen with an oncogenic activity in breast cancer.

Breast cancer is one of the most common cancers among women. To discover molecular targets that are applicable for development of novel breast cancer therapy, we previously did genome-wide expression profile analysis of 81 breast cancers and found dozens of genes that were highly and commonly up-regulated in breast cancer cells. Among them, we here focused on one gene that encodes PDZ-binding kinase/T-LAK cell-originated protein kinase (PBK/TOPK), including a kinase domain. Northern blot analyses using mRNAs of normal human organs, breast cancer tissues, and cancer cell lines indicated this molecule to be a novel cancer/testis antigen. Reduction of PBK/TOPK expression by small interfering RNA resulted in significant suppression of cell growth probably due to dysfunction in the cytokinetic process. Immunocytochemical analysis with anti-PBK/TOPK antibody implicated a critical role of PBK/TOPK in an early step of mitosis. PBK/TOPK could phosphorylate histone H3 at Ser10 in vitro and in vivo, and mediated its growth-promoting effect through histone H3 modification. Because PBK/TOPK is the cancer/testis antigen and its kinase function is likely to be related to its oncogenic activity, we suggest PBK/TOPK to be a promising molecular target for breast cancer therapy.

Antigens, Neoplasm↗

Identification of genes with altered expression in medullary breast cancer vs. ductal breast cancer and normal breast epithelia.

Medullary breast cancer (MCB) is a morphologically and biologically distinct subtype that, despite cytologically highly malignant characteristics, has a favorable prognosis compared to the more common infiltrating ductal breast carcinoma. MCB metastasizes less frequently, which has been attributed to both immunological and endogenous cellular factors, although little is known about the distinct biology of MCB that may contribute to the improved outcome of MCB patients. To identify candidate genes, we performed gene array expression analysis of cell lines of MCB, ductal breast cancer and normal breast epithelia, and the differential expression of a panel of candidate genes was further validated by quantitative PCR and immunohistochemical analysis of cell lines and tumor biopsies. A limited number of genes, including several members of the GAGE and insulin growth factor binding protein (IGFBP) gene families, Vav1, monoglyceride lipase and NADP+-dependent malic enzyme, exhibited altered expression in MCB vs. ductal breast cancer, and the differences for some of these genes were confirmed on an extended panel of cell lines by quantitative PCR. Immunohistochemical analysis further established that the expression of monoglyceride lipase was restricted to ductal breast cancer and present in 77% of these tumors, while Vav1 was restricted to MCB and present in 60% of tumors. In this study, we have identified genes that are differentially expressed in MCB vs. ductal breast cancer and further analysis of the gene products should illuminate the biological differences between MCB and ductal breast cancer.

Antigens, Neoplasm↗

Epidemiology, prevention, and early detection of breast cancer.

Breast cancer is the most common cancer among women worldwide. Genetic, environmental, and gene-environment interactions are discussed in relation to breast cancer etiology. A major advance in the study of inherited forms of breast cancer occurred with the identification of two genes, BRCA1 and BRCA2, that may account for a majority of inherited forms of breast cancer cases. Hypotheses have been formulated concerning the importance of timing of exposures to environmental agents and a possible role of "xenogenetics" in relation to breast cancer risk. With respect to early detection, regular mammography screening for women aged 50 years and older is clearly associated with a significant reduction in breast cancer mortality, but mammography among women aged 40 to 49 remains controversial. Concerning chemoprevention, the risks and benefits of tamoxifen continue to be clarified, retinoids hold promise, and monoterpenes have emerged as a possible chemopreventive agent.

Adult↗

Prevention of breast cancer.

Breast cancer is the most common cancer in women in the United Kingdom and despite advances in treatment, metastatic disease remains incurable and many women die from the disease. There is extensive biologic and clinical evidence implicating estrogenic stimulation in the development and progression of breast cancer. The success of tamoxifen in adjuvant breast cancer trials in delaying the recurrence of disease and preventing second primary breast cancers and, in postmenopausal women, conferring a survival benefit, has led to increasing interest in the use of tamoxifen as a chemopreventive agent against breast cancer. It remains to be seen whether tamoxifen will act as a true preventive agent or whether it will merely delay the appearance of breast cancer, in which case the use of the drug may alter the natural history of the disease in women who have been exposed to tamoxifen. The optimal duration of drug intervention, the appropriate target population for chemoprevention, and the cost-benefit ratio of tamoxifen prevention are all issues that must be formally addressed in carefully controlled trials. Some data concerning duration and side effects are already available from epidemiologic studies and long-term clinical follow-up of patients exposed to tamoxifen.

Antineoplastic Agents↗

Vitamin D receptor (VDR) expression is not a prognostic factor in breast cancer.

Breast cancer is characterized by its early haematogenous dissemination. Current modalities of risk assessment in lymph node-negative patients, to determine which patients should receive adjuvant chemotherapy, are not effective. The aim of this study was to analyze whether vitamin D receptor (VDR) status is a prognostic factor that may be of importance for the assessment of recurrence in breast cancer. VDR expression was analyzed immunohistochemically in breast cancer patients (n=228). No statistically significant correlations were found comparing VDR expression with histopathological data (tumor stage, lymph node status, grading, histological tumor type), with the expression of estrogen receptors (ER) or progesterone receptors (PR), with the proliferation marker Ki-67, with the tumor suppressor gene p53 or with the S-phase index. Our findings indicate that VDR protein expression is not a prognostic factor in breast cancer. The strong VDR immunoreactivity that we observed in breast cancer specimens supports the body of evidence that breast cancer may be a target for therapeutically applied vitamin D analogues.

Breast Neoplasms↗

A review of physical activity and breast cancer.

Breast cancer risk is influenced by endogenous hormones. Physical activity may offer one means for the primary prevention of breast cancer through its influence on ovarian hormones. This influence is manifested by changes in age at menarche and the number and nature of ovulatory menstrual cycles, factors that themselves are related to breast cancer risk. Animal experimental studies show that breast cancer risk is decreased by exercise at the time of tumor initiation but not necessarily by exercise during tumor promotion. Epidemiologic studies indicate, overall, a decreased risk of breast cancer among those women who are more physically active, whereas experimental studies of the effects of exercise in women have shown that exercise can influence characteristics of the menstrual cycle. Nevertheless, the experimental studies in women and epidemiologic studies of physical activity and breast cancer risk have been hampered by a number of methodologic limitations. The major problems in the epidemiologic studies include crude and incomplete measurements of physical activity over a woman's lifetime and inadequate control for potential confounding factors. Experimental studies of the effects of physical activity on menstrual activity in women have not adequately quantified the intensity of activity and the resultant effects on menstrual cycle changes.

Animals↗

Pharmacotherapy for male breast cancer.

Breast cancer in males is uncommon, occurring at approxiamtely 1% of the rate of female breast cancer. Male breast carcinomas tend to be highly positive for hormone receptors, including oestrogen, progesterone and androgen receptors. Owing to this, hormone therapy is recommended as the primary treatment modality. Adjuvant therapy is recommended for male breast cancers with large size or positive axillary nodes. For metastatic disease, options for therapy include tamoxifen, orchiectomy, anti-androgens with or without luteinising hormone releasing hormone analogues or combination chemotherapy. The newer hormonal treatments, such as the selective aromatase inhibitors or novel antioestrogens, have not yet been well studied in male breast cancer but have potential for efficacy in this disease.

Androgen Antagonists↗

Differences in Ki67 and c-erbB2 expression between screen-detected and true interval breast cancers.

Breast cancer screening facilitates the early detection of breast cancer, although a significant number of tumors still arise in the interval between screening. The objective of this study was to measure the expression of five markers of proven prognostic significance in symptomatic breast cancer (estrogen receptor, progesterone receptor, p53, Ki67, and c-erbB2) in screen-detected and interval breast cancers to identify biological markers that may be associated with the emergence of symptomatic breast cancer in the screening interval. The expression of estrogen receptor, progesterone receptor, p53, Ki67, and c-erbB2 was assessed in a series of 51 true interval and 84 screened-detected invasive tumors by immunohistochemistry. Interval cancers tended to be of higher histological grade and were of larger pathological size than screen-detected cancers. Expression of estrogen receptor was 1.7-fold lower (P<0.001), whereas expression of p53 was 2.5-fold (P<0.01), Ki67 2.4-fold (P<0.001), and c-erbB2 3.6-fold higher (P<0.01) in true interval cancers compared with screen-detected invasive cancers. There was no significant difference in progesterone receptor expression. The most important differences identified by multiple logistic regression analysis were in the expression of Ki67 and c-erbB2. The differences in the expression of these markers were more important than clinical features such as pathological grade and size. Using the logistic regression model, 83% of the tumors analyzed in this study could be correctly assigned as interval or screen-detected tumors on the basis of Ki67 and c-erbB2 expression. The importance of high expression of Ki67 in interval cancers compared with screen-detected cancers suggests that tumors may become symptomatic in the screening interval as a result of increased levels of cell proliferation. The inclusion of c-erbB2 in the regression equation suggests that this growth factor receptor may play a significant role in stimulating the rapid growth of interval cancers.

Aged↗

BRCA1 and BRCA2 in breast cancer.

Breast cancer, one of the most common serious malignancies affecting women, occurs in hereditary and sporadic forms. Hereditary breast cancer accounts for 5-10% of all cases and has some distinctive clinical features compared with sporadic breast cancer. The recently identified genes BRCA1 and BRCA2 appear to account for the majority of hereditary breast cancer in US and European populations. Both of these genes have already been localized and isolated; however, the exact functions of their proteins are not clear yet. The detection of LOH in the 17q21 and 13q12-q13 regions, where the BRCA1 and BRCA2 genes are located, indicates that BRCA1 and BRCA2 act as tumor suppressor genes. The list of identified germline mutations in BRCA1 and BRCA2 is still growing, and mutation carriers have a substantial lifetime risk of both breast and ovarian cancer. However, it is still undetermined whether BRCA1 and BRCA2 play similar important roles in sporadic breast cancer. This paper reviews the current advances in BRCA1/BRCA2 research: the structure of their genes and proteins, their mutation frequencies, their possible roles in both hereditary and sporadic breast cancers, and their functions in transcriptional regulation and DNA repair.

BRCA1 Protein↗

Mechanisms in the skeletal complications of breast cancer.

Breast cancer is the most common malignancy in women, with a worldwide prevalence of 1.5 million throughout the industrialized countries. Its mortality rate is second only to lung cancer in the USA and Europe. Its high incidence and prevalence makes it a major public health problem. Up to one-third of women with early stage breast cancer will eventually succumb to the disease, and most of these will develop bone metastases during the course of the disease. Approximately 70% of patients with breast cancer have bone metastases, with 27% having lung and liver metastases. Hypercalcemia also is very common in advanced breast cancer, manifesting itself in one-third of patients late in the disease. Breast cancer accounts for approximately 25% of the cases of hypercalcemia in cancer. The major skeletal complications of breast cancer--hypercalcemia and bone metastases--almost certainly share certain mechanisms and these will be discussed.

Bone Neoplasms↗

Second primary cancers following breast cancer in the Japanese female population.

To assess the risk of developing second primary cancers following breast cancer in Japanese females, we performed a retrospective cohort study of 2786 patients who were newly diagnosed with breast cancer at our hospital between 1970 - 1994, until the end of 1995 (average follow-up period, 8.6 years). The expected number of each second primary cancer was calculated by multiplying the number of appropriate person-years at risk by the corresponding age- and calendar period-specific cancer incidence rates for women obtained from the Osaka Cancer Registry. One hundred and seventeen patients developed a second primary cancer other than subsequent breast cancer, yielding an observed-to-expected ratio (O / E) of 1.3 [95% confidence interval (CI) = 1.1 - 1.6]. The risk for developing a second primary cancer was significantly elevated during the first year following the diagnosis of breast cancer, and decreased with the passage of time to unity. A significantly increased risk was noted for the development of ovarian cancer (O / E = 2.4, 95% CI = 1.0 - 4.6), thyroid cancer (O / E = 3.7, 95% CI = 1.5 - 7.6) and non-Hodgkin's lymphoma (NHL) (O / E = 3.5, 95% CI = 1.4 - 7.1) among the breast cancer patients compared with the general population. Patients who received hormonal therapy as the breast cancer treatment showed a significantly increased risk for ovarian cancer (O / E = 5.5, 95% CI = 1.8 - 12.9). Patients who received chemotherapy as the breast cancer treatment had an increased risk for NHL (O / E = 5.0, 95% CI = 1.6 - 11.6). These findings indicate that Japanese female patients with breast cancer had a 30% higher risk of developing a second primary cancer than the general population, the higher risk being manifested in the early period following the diagnosis of breast cancer. Medical surveillance of breast cancer patients for NHL, as well as for ovarian cancer and thyroid cancer, is required.

Adult↗

Tissue and serum sialidase levels in breast cancer.

Breast cancer is both one of the most common and one of the most treatable of all human malignancies. It has been suggested by various investigators that sialic acid increases in the sera of cancerous patients. In cancer patients, an increase in the levels of serum sialic acid may also be due to an increase in the activity of serum or tissue sialidase. The purpose of the present investigation was to determine whether the concentration of sialidase in serum and breast tissue could be used as a tumor marker in breast cancer. In this study; serum sialidase levels in 26 patient with breast cancer and 31 controls were found to be 77.04+/-25.07 U/l and 55.56+/-7.50 U/l, respectively. The mean tissue sialidase levels in 26 breast cancer patients and 13 controls were 39.76+/-17.03 U/g protein and 14.30+/-7.09 U/g protein, respectively. Serum and tissue sialidase levels in breast cancer were significantly higher than those found in the control group (P < 0.001). The mean serum and tissue sialidase levels in 14 Grade I-II and 12 Grade III breast cancer patients were found to be 67.73+/-11.87 U/l and 33.41+/-12.17 U/g protein and 87.89+/-31.94 U/l and 47.17+/-19.30 U/g protein, respectively. Also we found a significant difference between the levels of serum and tissue sialidase in Grade I-II and III (P < 0.05).

Biomarkers, Tumor↗

Genomic approaches in the management and treatment of breast cancer.

Breast cancer is the most common malignancy afflicting women from Western cultures. It has been estimated that approximately 211 000 women will be diagnosed with breast cancer in 2003 in the United States alone, and each year over 40 000 women will die of this disease. Developments in breast cancer molecular and cellular biology research have brought us closer to understanding the genetic basis of this disease. Unfortunately, this information has not yet been incorporated into the routine diagnosis and treatment of breast cancer in the clinic. Recent advancements in microarray technology hold the promise of further increasing our understanding of the complexity and heterogeneity of this disease, and providing new avenues for the prognostication and prediction of breast cancer outcomes. The most recent application of microarray genomic technologies to studying breast cancer will be the focus of this review.

Biomarkers, Tumor↗

COX-2 induction by heparanase in the progression of breast cancer.

Breast cancer confined within the lactiferous duct or lobule, without invading the stroma, is called ductal carcinoma in situ (DCIS), whereas breast cancer that has invaded the stroma through the basal membrane is called invasive cancer. Heparanase, an endo-beta-D-glucuronidase that specifically degrades heparan sulfate proteoglycans (HSPGs) in the extracellular matrix (ECM), plays an important role when breast cancer cells breach the basal membrane. Recently, we have reported that heparanase is involved in angiogenesis through direct induction of cyclo-oxygenase-2 (COX-2). COX-2 induces vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) and is thus involved in neovascularization. The present study was undertaken to analyze surgically resected breast cancer specimens for heparanase and COX-2 expression, using specimens from 59 patients with invasive cancer and 85 patients with DCIS (including 41 cases of DCIS adjacent to invasive cancer). This study yielded the following results: a) the distribution of heparanase within tumor tissue was identical to that of COX-2; b) heparanase expression was more frequent in invasive cancer than in non-invasive cancer; c) a close positive correlation was noted between heparanase and COX-2 expression (this correlation was particularly strong in cases of invasive cancer); and d) COX-2 expression was always seen in cases positive for heparanase expression. Our results indicate that heparanase expression increases during the progression of breast cancer into invasive cancer, and that this change is accompanied by increased COX-2 expression. They also suggest that heparanase may play a novel role for COX-2 mediated tumor angiogenesis in breast-cancer progression.

Adult↗

Genomic approaches to understanding and treating breast cancer.

Breast cancer is the most common malignancy afflicting women from Western cultures. It has been estimated that approximately 211,000 women will be diagnosed with breast cancer in 2003 in the United States alone, and distressingly each year over 40,000 women will die of this disease. Developments in breast cancer molecular and cellular biology research have brought us closer to understanding the genetic basis of this disease. Unfortunately, this information has not yet to be incorporated into the routine diagnosis and treatment of breast cancer in the clinic. Recent advancements in microarray technology hold the promise of further increasing our understanding of the complexity and heterogeneity of this disease, and providing new avenues for the prognostication and prediction of breast cancer outcomes. The most recent application of microarray genomic technologies to studying breast cancer will be the focus of this review.

Journal Article↗