Myoepithelial molecular markers in human breast carcinoma PMC42-LA cells are induced by extracellular matrix and stromal cells

The microenvironment plays a key role in the cellular differentiation of the two main cell lineages of the human breast, luminal epithelial, and myoepithelial. It is not clear, however, how the components of the microenvironment control the development of these cell lineages. To investigate how lineage development is regulated by 3-D culture and microenvironment components, we used the PMC42-LA human breast carcinoma cell line, which possesses stem cell characteristics. When cultured on a two-dimensional glass substrate, PMC42-LA cells formed a monolayer and expressed predominantly luminal epithelial markers, including cytokeratins 8, 18, and 19; E-cadherin; and sialomucin. The key myoepithelial-specific proteins alpha-smooth muscle actin and cytokeratin 14 were not expressed. When cultured within Engelbreth-Holm- Swarm sarcoma-derived basement membrane matrix (EHS matrix), PMC42-LA cells formed organoids in which the expression of luminal markers was reduced and the expression of other myoepithelial-specific markers (cytokeratin 17 and P-cadherin) was promoted. The presence of primary human mammary gland fibroblasts within the EHS matrix induced expression of the key myoepithelial-specific markers, alpha-smooth muscle actin and cytokeratin 14. Immortalized human skin fibroblasts were less effective in inducing expression of these key myoepithelial-specific markers. Confocal dual-labeling showed that individual cells expressed luminal or myoepithelial proteins, but not both. Conditioned medium from the mammary fibroblasts was equally effective in inducing myoepithelial marker expression. The results indicate that the myoepithelial lineage is promoted by the extracellular matrix, in conjunction with products secreted by breast-specific fibroblasts. Our results demonstrate a key role for the breast microenvironment in the regulation of breast lineage development.

Pain during mammography: implications for breast screening programmes

Pain experienced during mammography can deter women from attending for breast cancer screening. Review of the current literature on pain experienced during mammography reveals three main areas of interest: reports of the frequency of pain, identification of predictors of pain and strategies for responding to pain. Implications of this literature for breast screening programmes include the need for appropriate measurements of pain during mammography that are valid for screening populations, a further understanding of organizational factors involved in screening programmes that may be predictors of pain and for the development of valid strategies for responding to pain within breast screening programmes.

Womens satisfaction with their breast prosthesis: What determines a quality prosthesis

The aim of this study is to determine what factors constitute a quality prosthesis and ascertain which factors affect prosthesis satisfaction. Sixty-four women who received full funding for their prosthesis and 38 women who received their hospital’s usual fundingwere recruited. Women rated the information provided about breast prostheses very highly, with 85% reporting that it was "very good" or "excellent." Satisfaction was significantly associatedwith how well the prosthesis fit (1 week,p=.001; 3 months,p=.01), level of comfort (3 months,p=.005), and appearance of the prosthesis when worn (6 months,p = .001). Quality was significantly associated with how well it fit (1 week,p = .001; 3months,p = .001), how natural it felt (1 week,p = .001; 6months,p=.01), the weight of the prosthesis (3 months,p=.003), and appearance when worn (6 months,p = .03). The results will be used to improve women’s access to a quality prosthesis.

Quality of care for women presenting with benign breast conditions

The aim of the study was to investigate the management of women with benign breast problems. A consecutive sample of women (n = 194) was assessed who presented to public or private sector providers. The main reasons for referral were breast lumps (62%); 56% of women who attended the public sector did not receive any recommendation compared to 40% who attended the private sector and clinical/general practitioner reviews were recommended to more women in the private sector (54%). Reasons for the discrepancy between public and private patients require further investigation. (Intern Med J 2005; 35: 357–358)

Access to breast prostheses via a government-funded service in Victoria, Australia

For many women, the only alternative to breast reconstruction following a mastectomy is to use external prostheses, which need replacing regularly at a cost of up to $395 per prosthesis. Commonwealth and state governments across Australia have responded to this need by providing subsidies to assist in the purchase of breast prostheses. However, current arrangements have been highly variable and sometimes difficult to access. As part of a larger review of breast pros-thesis services in Victoria, Australia, the aim of this research was to evaluate client satisfaction among Victorian women who accessed funds through the State Government's Aids and Equipment Program, compare the responses of the program service providers with the experiences of clients accessing funding, and identify opportunities to improve service provision.

Experiences of men with breast cancer: a qualitative study

Background
Recent reports indicate that male breast cancer rates are increasing in North America. While there have been numerous large-scale studies examining women's experiences with breast cancer, to date there have been no North American studies examining what a man experiences with a breast cancer diagnosis. The objective of this qualitative study was to describe the experiences of a sample of Canadian men diagnosed with breast cancer.

Methods
After written informed consent, unstructured audio-taped interviews were conducted with 20 men. Since little is known about a man's experience with breast cancer, an exploratory qualitative approach was utilized.

Results
Participants experienced concerns related to the lack of awareness of male breast cancer within both public and health professional groups. Many men suffered stress related to the cancer diagnosis, body image concerns and role strain. The lack of male-specific breast cancer information was identified as a major concern. All denied interest in traditional support groups. In retrospect, a number of men felt the breast cancer experience vastly improved their lives.

Conclusions
Needs identified by participants include increased public and health professional awareness of male breast cancer, written information specific for men, and male participation in breast cancer research. Further study is also necessary to identify supports considered helpful by men with breast cancer and other malignancies.

Induction of epithelial to mesenchymal transition in PMC42-LA human breast carcinoma cells by carcinoma-associated fibroblast secreted factors

Background
Breast carcinoma is accompanied by changes in the acellular and cellular components of the microenvironment, the latter typified by a switch from fibroblasts to myofibroblasts.


Methods
We utilised conditioned media cultures, Western blot analysis and immunocytochemistry to investigate the differential effects of normal mammary fibroblasts (NMFs) and mammary cancer-associated fibroblasts (CAFs) on the phenotype and behaviour of PMC42-LA breast cancer cells. NMFs were obtained from a mammary gland at reduction mammoplasty, and CAFs from a mammary carcinoma after resection.


Results
We found greater expression of myofibroblastic markers in CAFs than in NMFs. Medium from both CAFs and NMFs induced novel expression of α-smooth muscle actin and cytokeratin-14 in PMC42-LA organoids. However, although conditioned media from NMFs resulted in distribution of vimentin-positive cells to the periphery of PMC42-LA organoids, this was not seen with CAF-conditioned medium. Upregulation of vimentin was accompanied by a mis-localization of E-cadherin, suggesting a loss of adhesive function. This was confirmed by visualizing the change in active β-catenin, localized to the cell junctions in control cells/cells in NMF-conditioned medium, to inactive β-catenin, localized to nuclei and cytoplasm in cells in CAF-conditioned medium.


Conclusion
We found no significant difference between the influences of NMFs and CAFs on PMC42-LA cell proliferation, viability, or apoptosis; significantly, we demonstrated a role for CAFs, but not for NMFs, in increasing the migratory ability of PMC42-LA cells. By concentrating NMF-conditioned media, we demonstrated the presence of factor(s) that induce epithelial-mesenchymal transition in NMF-conditioned media that are present at higher levels in CAF-conditioned media. Our in vitro results are consistent with observations in vivo showing that alterations in stroma influence the phenotype and behaviour of surrounding cells and provide evidence for a role for CAFs in stimulating cancer progression via an epithelial-mesenchymal transition. These findings have implications for our understanding of the roles of signalling between epithelial and stromal cells in the development and progression of mammary carcinoma.

Kernel-based naive bayes classifier for breast cancer prediction

The classification of breast cancer patients is of great importance in cancer diagnosis. Most classical cancer classification methods are clinical-based and have limited diagnostic ability. The recent advances in machine learning technique has made a great impact in cancer diagnosis. In this research, we develop a new algorithm: Kernel-Based Naive Bayes (KBNB) to classify breast cancer tumor based on memography data. The performance of the proposed algorithm is compared with that of classical navie bayes algorithm and kernel-based decision tree algorithm C4.5. The proposed algorithm is found to outperform in the both cases. We recommend the proposed algorithm could be used as a tool to classify the breast patient for early cancer diagnosis.

Understanding women's breast screening behaviour: a study carried out in South East London, with women aged 50-64 years

Objective To understand low uptake of breast cancer screening through exploring the personal reasoning underlying women's attendance or non-attendance, and identifying differences between those who attend and those who decline.

Design Cross-sectional survey.

Setting Community and home environments of women eligible for breast screening aged 50—64 years, living in South East London. Method Structured, self-completed or assisted-completion questionnaires.

Results The decision to attend or decline screening is rational and personally justifiable, engaging factors linked to emotions and attitude. Attitudes about breast screening and perceived personal importance of breast screening are the strongest predictors of attendance and non-attendance. There are differences between ethnic groups in perceptions of breast screening. Regular attendance at screening is associated with ethnicity, although consistent avoidance of mammography is not. Inconvenience is an important factor in missing appointments, and tends to be prolonged rather than specific to the time or day of the pre-booked invitation. GP and health worker advice are good persuaders towards attendance. Pain and anxiety during mammography are notable dissuaders against re-attending.

Conclusion Appropriate service provision requires consideration of local factors, as well as the medical needs of the population eligible for breast screening. Lay perceptions of potential personal costs of attending or not attending breast screening are important for guiding health promotion. Information providers should consider the language needs of a culturally and educationally mixed community. Health care professionals are well placed to encourage uptake of breast screening through disseminating information that promotes attendance, both within and outside the breast screening service.

Metallothionein 2A expression is associated with cell proliferation in breast cancer

Metallothioneins (MTs) belong to a family of cysteine-rich, metal-binding intracellular proteins, which have been linked with cell proliferation. In this study, expression levels of the 8 known MT-1 and MT-2 functional isoforms in human invasive ductal breast cancer specimens were determined by RT–PCR. The expression profiles of the MT protein and MT-2A mRNA were further evaluated in 79 cases of human invasive ductal breast carcinoma by immunohistochemistry and in situ hybridization, and correlated with cancer cell proliferation (determined by Ki-67 nuclear antigen immunolabeling). MT-1A, MT-1E, MT-1F, MT-1G, MT-1H, MT-1X and MT-2A but not MT-1B, were detected in breast cancer tissue samples. The MT-2A mRNA transcript was the highest among all the isoforms detected. A positive correlation was observed between MT-2A mRNA and MT protein expression with Ki-67 labeling (P = 0.0003 and P < 0.0001, respectively) but not with apoptosis (P = 0.1244 and P = 0.8189, respectively). Co-localization of the MT protein and Ki-67 nuclear antigen in breast cancer cells was demonstrated by double immunofluorescence staining. There was also significantly higher MT protein and MT-2A mRNA expression in histological grade 3 tumors than in histological grade 1 and 2 tumors. The finding that MT 2A appears to be the main isoform associated with cell proliferation in invasive ductal breast cancer tissues, may have therapeutic implications.

External breast prosthesis use: experiences and views of women with breast cancer, breast care nurses, and prosthesis fitters

After mastectomy, the provision of an appropriate breast prosthesis can help to improve body image and quality of life and reduce associated emotional distress. Although up to 90% of women use an external breast prosthesis after mastectomy, little is known about their experiences and satisfaction with breast prosthesis use. Focus groups were conducted with women who had been fitted with an external breast prosthesis, breast care nurses, and prosthesis fitters to explore women's experiences of prosthesis use. Qualitative thematic content analysis of focus group transcripts indicated that whereas women's initial reaction to the prosthesis generally was negative, this improved over time. Provision of adequate information and support, characteristics of the fitter and the fitting experience, and relationships with breast care nurses and prosthesis fitters were important to women's acceptance and satisfaction with their prosthesis. The study results highlighted the key role that breast care nurses play and the underestimation of the prosthesis fitter's role. Common themes concerning the impact of prosthesis use included body image, appearance, and feminine identity. These findings have important implications for professionals involved in the delivery of breast prostheses services.

The breast cancer related burden of morbidity and mortality in six European coutries

Background: The burden of breast cancer expressed in Disability Adjusted Life Years (DALYs) was compared for six European countries and its sensitivity to different sources of variation examined. Methods: DALYs were calculated using country-specific epidemiological data and European Disability Weights. Epidemiological data for 1996 were obtained for Denmark, England and Wales, France, the Netherlands, Spain and Sweden. Disability weights were empirically derived. Results:  Denmark and the Netherlands lost the largest number of DALYs (approximately 1100 DALYs per 100,000 women). They were followed by England (87% of the Danish burden), France (72%), Sweden (68%) and Spain (67%). 70 to 80% of the burden was caused by mortality. Cross-national variation in disease epidemiology was the largest source of variation in the burden of breast cancer. Variation in disability weights and uncertainty in epidemiological data had smaller effects. Conclusion: To compare the burden of breast cancer and most other types of cancer mortality rates provide sufficient information.

Extracellular matrix induces formation of organoids and changes in cell surface morphology in cultured human breast carcinoma cells PMC42-LA

In the lactating breast, the development of secretory alveoli consisting of differentiated cells arranged around a central lumen is dependent on signals from the extracellular environment of the cells. There are few cell lines that model this process. We previously showed that the human breast carcinoma line PMC42-LA can be induced to form organoids, reminiscent of secretory alveoli found in the lactating human breast. In this report, we used high-resolution scanning electron microscopy to show that the formation of organoids is accompanied by development of cell surface microvilli. Extracellular matrix-induced formation of microvilli occurred on the internal and external surfaces of cells in the organoids and not on surfaces in contact with the extracellular matrix. Organoid formation of PMC42-LA cells induced a rearrangement of the extracellular matrix, seen in the form of radiating fibers from the organoids. In summary, there is an interaction between PMC42-LA cells and the underlying extracellular matrix, which leads to the formation of polarized cells with well-developed microvilli. This is accompanied by organization of the extracellular matrix. PMC42-LA is a relevant model of the human breast for investigations into cell-cell and cell-matrix interactions.