The molecular genetics of breast cancer: The contribution of comparative genomic hybridization

Comparative genomic hybridization (CGH) has been the technique of choice over the last 10 years for mapping DNA copy number changes in human tumors. Here we review the literature to demonstrate how CGH has contributed to the comprehension of molecular aspects of breast tumorigenesis. At least two distinct molecular pathways of breast cancer have been characterized that show a strong correlation with histological grade. It seems that grade I invasive ductal carcinomas (IDCs) arise from well-differentiated ductal carcinoma in situ (DCIS), whereas grade III IDCs come from poorly differentiated DCIS. In addition, dedifferentiation from a low- to a high-grade breast cancer has proven an unlikely phenomenon. CGH has been instrumental in dissecting distinct molecular pathways toward breast malignancy and in establishing a direct relationship between genotype and clinical pathological features. (C) 2005 Elsevier GrnbH. All rights reserved.

Plasma membrane calcium-ATPase 2 and 4 in human breast cancer cell lines

There is evidence to suggest that plasma membrane Ca2+-ATPase (PMCA) isoforms are important mediators of mammary gland physiology. PMCA2 in particular is upregulated extensively during lactation. Expression of other isoforms such as PMCA4 may influence mammary gland epithelial cell proliferation and aberrant regulation of PMCA isoform expression may lead or contribute to mammary gland pathophysiology in the form of breast cancers. To explore whether PMCA2 and PMCA4 expression may be deregulated in breast cancer, we compared mRNA expression of these PMCA isoforms in tumorigenic and non-tumorigenic human breast epithelial cell lines using real time RT-PCR. PMCA2 mRNA has a higher level of expression in some breast cancer cell lines and is overexpressed more than 100-fold in ZR-75-1 cells, compared to non-tumorigenic 184135 cells. Although differences in PMCA4 mRNA levels were observed between breast cell lines, they were not of the magnitude observed for PMCA2. We conclude that PMCA2 mRNA can be highly overexpressed in some breast cancer cells. The significance of PMCA2 overexpression on tumorigenicity and its possible correlation with other properties such as invasiveness requires further study. (c) 2005 Elsevier Inc. All rights reserved.

The impact of rehabilitation support services on health-related quality of life for women with breast cancer

As the number of women surviving breast cancer increases, with implications for the health system, research into the physical and psychosocial sequelae of the cancer and its treatment is a priority. This research estimated self-reported health-related quality of life (HRQoL) associated with two rehabilitation interventions for breast cancer survivors, compared to a non-intervention group. Women were selected if they received an early home-based physiotherapy intervention (DAART, n = 36) or a group-based exercise and psychosocial intervention (STRETCH, n = 31). Questionnaires on HRQoL, using the Functional Assessment of Cancer Therapy - Breast Cancer plus Arm Morbidity module, were administered at pre-, post-intervention, 6- and 12-months post-diagnosis. Data on a non-intervention group (n = 208) were available 6- and 12-months post-diagnosis. Comparing pre/post-intervention measures, benefits were evident for functional well-being, including reductions in arm morbidity and upper-body disability for participants completing the DAART service at one-to-two months following diagnosis. In contrast, minimal changes were observed between pre/post-intervention measures for the STRETCH group at approximately 4-months post-diagnosis. Overall, mean HRQoL scores (adjusted for age, chemotherapy, hormone therapy, high blood pressure and occupation type) improved gradually across all groups from 6- to 12-months post-diagnosis, and no prominent differences were found. However, this obscured declining HRQoL scores for 20-40% of women at 12 months post-diagnosis, despite receiving supportive care services. Greater awareness and screening for adjustment problems among breast cancer survivors is required throughout the disease trajectory. Early physiotherapy after surgery has the potential for short-term functional, physical and overall HRQoL benefits.

Randomized controlled trial of an educational intervention for managing fatigue in women receiving adjuvant chemotherapy for early-stage breast cancer

Purpose To evaluate the efficacy of a psychoeducational intervention in improving cancer-related fatigue. Patients and Methods This randomized controlled trial involved 109 women commencing adjuvant chemotherapy for stage I or II breast cancer in five chemotherapy treatment centers. Intervention group patients received an individualized fatigue education and support program delivered in the clinic and by phone over three 10- to 20-minute sessions 1 week apart. Instruments included a numeric rating scale assessing confidence with managing fatigue; 11-point numeric rating scales measuring fatigue at worst, average, and best; the Functional Assessment of Cancer Therapy-Fatigue and Piper Fatigue Scales; the Cancer Self-Efficacy Scale; the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30; and the Hospital Anxiety and Depression Scale. For each outcome, separate analyses of covariance of change scores between baseline (T1) and the three follow-up time points (T2, T3, and T4) were conducted, controlling for the variable's corresponding baseline value. Results Compared with the intervention group, mean difference scores between the baseline (T1) and immediate after the test (T2) assessments increased significantly more for the control group for worst and average fatigue, Functional Assessment of Cancer Therapy-Fatigue, and Piper fatigue severity and interference measures. These differences were not observed between baseline and T3 and T4 assessments. No significant differences were identified for any pre- or post-test change scores for confidence with managing fatigue, cancer self-efficacy, anxiety, depression, or quality of life. Conclusion Preparatory education and support has the potential to assist women to cope with cancer-related fatigue in the short term. However, further research is needed to identify ways to improve the potency and sustainability of psychoeducational interventions for managing cancer-related fatigue.

A cost-effectiveness analysis of two rehabilitation support services for women with breast cancer

The purpose of this research was to estimate the cost-effectiveness of two rehabilitation interventions for breast cancer survivors, each compared to a population-based, non-intervention group (n = 208). The two services included an early home-based physiotherapy intervention (DAART, n = 36) and a group-based exercise and psychosocial intervention (STRETCH, n = 31). A societal perspective was taken and costs were included as those incurred by the health care system, the survivors and community. Health outcomes included: (a) 'rehabilitated cases' based on changes in health-related quality of life between 6 and 12 months post-diagnosis, using the Functional Assessment of Cancer Therapy - Breast Cancer plus Arm Morbidity (FACT-B+4) questionnaire, and (b) quality-adjusted life years (QALYs) using utility scores from the Subjective Health Estimation (SHE) scale. Data were collected using self-reported questionnaires, medical records and program budgets. A Monte-Carlo modelling approach was used to test for uncertainty in cost and outcome estimates. The proportion of rehabilitated cases was similar across the three groups. From a societal perspective compared with the non-intervention group, the DAART intervention appeared to be the most efficient option with an incremental cost of $1344 per QALY gained, whereas the incremental cost per QALY gained from the STRETCH program was $14,478. Both DAART and STRETCH are low-cost, low-technological health promoting programs representing excellent public health investments.

The impact of breast cancer on the lives of middle-aged women: Results from the Australian longitudinal study of women's health

This article investigated the impact of breast cancer (BC) in middle-aged Australian women (45-50 years). Two waves of data collected 2 years apart from a longitudinal survey of 12,177 women identified 3 groups: (a) 11,933 (98%) who reported never having had BC, (b) 181 (1.5%) who reported a diagnosis of BC at Time 1, and (c) 63 (0.5%) who reported onset of BC between Time I and Time 2. Repeated measures analysis of variance was used to compare the 3 groups. Women with recent onset of BC experienced significant changes across a range of functioning compared with the other 2 groups. Compared with women with no BC, women with longer established onset of BC had significantly worse health and social outcomes, but these were associated with small effect sizes. Both groups of women with BC reported less impact on mental and emotional health than on other areas of functioning.

Psychosocial impact of newly diagnosed advanced breast cancer

The purpose of this study was to delineate the key emotional concerns of women newly diagnosed with recurrent or metastatic breast cancer. Sixty-six women diagnosed with metastatic breast cancer within the previous 6 months, receiving treatment at the Medical Oncology Departments of two metropolitan teaching hospitals, completed measures of HADS, IES, CARES-SF and Memorial Symptom Assessment Scale, and participated in a semistructured interview. There were high levels of psychological morbidity, 56.7% of women younger than 55 years qualifying as 'cases' on the HADS, compared with 34.5% of women aged over 55 years. The total HADS score was significantly correlated with the Global and Physical Subscales of the MSAS and CARES. Women younger than 55 years had significantly higher levels of intrusive and avoidant symptoms than women over 55 years. Women also reported high numbers of physical symptoms. Key themes which emerged during the interviews were: difficulties in communicating with doctors, perceived delay in diagnosis, the emotional impact, concerns about the family, feelings about why the cancer developed, other life stress and trauma, and use of non-prescribed treatments. Copyright (c) 2004 John Wiley & Sons, Ltd.

Molecular characterization and cancer risk associated with BRCA1 and BRCA2 splice site variants identified in multiple-case breast cancer families

Genetic screening of women from multiple-case breast cancer families and other research-based endeavors have identified an extensive collection of germline variations of BRCA1 and BRCA2 that can be classified as deleterious and have clinical relevance. For some variants, such as those in the conserved intronic splice site regions which are highly likely to alter splicing, it is not possible to classify them based on the identified DNA sequence variation alone. We studied 11 multiple-case breast cancer families carrying seven distinct splice site region genetic alterations in BRCA1 or BRCA2 (BRCA1, c.IVS6-2delA, c.IVS9-2A>C, c.IVS4-1G>T, c.IVS20+1G>A and BRCA2, c.IVS17-1G>C, c.IVS20+1G>A, c.IVS7-1G>A) and applied SpliceSiteFinder to predict possible changes in efficiency of splice donor and acceptor sites, characterized the transcripts, and estimated the average age-specific cumulative risk (penetrance) using a modified segregation analysis. SpliceSiteFinder predicted and we identified transcipts that illustrated that all variants caused exon skipping, and all but two led to frameshifts. The risks of breast cancer to age 70 yrs, averaged over all variants, over BRCA1 variants alone, and over BRCA2 variants alone, were 73% (95% confidence interval 47-93), 64% (95%CI 28-96) and 79% (95%CI 48-98) respectively (all P

Isoform specific changes in PPAR alpha and beta in colon and breast cancer with differentiation

To investigate the role of peroxisome proliferator-activated receptors (PPARs) chi and beta in the differentiation of colon cancer cells, we differentiated HT-29 cells using sodium butyrate (NaB) and culturing post-confluence and assessed differentiation using the marker intestinal alkaline phosphatase. While PPAR chi levels only changed with culturing post confluence, PPAR beta levels increased independent of the method of differentiation. To explore further the differences induced by NaB. we assessed changes in both PPAR isoforms in MCF-7 breast cancer cells cultured in the presence of NaB over 48 h. Again a very different expression pattern was observed with PPAR-1 increasing after 4 h and remaining elevated, while PPAR beta increased transiently. Our studies suggest that the expression of PPARs is dependent upon both the method of differentiation and on time. Moreover, these studies show that changes in levels are not required for the differentiation of colon cancer cell lines, whereas changes in PPAR beta are more closely associated with differentiation. (c) 2005 Elsevier Inc. All rights reserved.

Cost-effectiveness of screening with contrast enhanced magnetic resonance imaging vs X-ray mammography of women at a high familial risk of breast cancer

Contrast enhanced magnetic resonance imaging (CE MRI) is the most sensitive tool for screening women who are at high familial risk of breast cancer. Our aim in this study was to assess the cost-effectiveness of X-ray mammography (XRM), CE MRI or both strategies combined. In total, 649 women were enrolled in the MARIBS study and screened with both CE MRI and mammography resulting in 1881 screens and 1-7 individual annual screening events. Women aged 35-49 years at high risk of breast cancer, either because they have a strong family history of breast cancer or are tested carriers of a BRCA1, BRCA2 or TP53 mutation or are at a 50% risk of having inherited such a mutation, were recruited from 22 centres and offered annual MRI and XRM for between 2 and 7 years. Information on the number and type of further investigations was collected and specifically calculated unit costs were used to calculate the incremental cost per cancer detected. The numbers of cancer detected was 13 for mammography, 27 for CE MRI and 33 for mammography and CE MRI combined. In the subgroup of BRCA1 (BRCA2) mutation carriers or of women having a first degree relative with a mutation in BRCA1 (BRCA2) corresponding numbers were 3 (6), 12 (7) and 12 (11), respectively. For all women, the incremental cost per cancer detected with CE MRI and mammography combined was 28 pound 284 compared to mammography. When only BRCA1 or the BRCA2 groups were considered, this cost would be reduced to 11 pound 731 (CE MRI vs mammography) and 15 pound 302 (CE MRI and mammography vs mammography). Results were most sensitive to the unit cost estimate for a CE MRI screening test. Contrast-enhanced MRI might be a cost-effective screening modality for women at high risk, particularly for the BRCA1 and BRCA2 subgroups. Further work is needed to assess the impact of screening on mortality and health-related quality of life.

A novel plant toxin, persin, with in vivo activity in the mammary gland, induces Bim-dependent apoptosis in human breast cancer cells

Phytochemicals have provided an abundant and effective source of therapeutics for the treatment of cancer. Here we describe the characterization of a novel plant toxin, persin, with in vivo activity in the mammary gland and a p53-, estrogen receptor-, and Bcl-2-independent mode of action. Persin was previously identified from avocado leaves as the toxic principle responsible for mammary gland-specific necrosis and apoptosis in lactating livestock. Here we used a lactating mouse model to confirm that persin has a similar cytotoxicity for the lactating mammary epithelium. Further in vitro studies in a panel of human breast cancer cell lines show that persin selectively induces a G(2)-M cell cycle arrest and caspase-dependent apoptosis in sensitive cells. The latter is dependent on expression of the BH3-only protein Bim. Bim is a sensor of cytoskeletal integrity, and there is evidence that unique structure of the compound, persin could represent a novel class of microtubule-targeting agent with potential specificity for breast cancers.