A better understanding of how breast cancer occurs
The National Centres of Competence in Research (NCCRs) operate on an interdisciplinary principle. In one project carried out by the NCCR “Molecular Oncology – From Basic Research to Therapeutic Approaches", a biologist at the EPF Lausanne and a pathologist from the Lausanne University Hospital are studying how breast cells are attacked by cancer.
"We didn’t plan on working together to start with," comments Cathrin Brisken. "After all, we come from two very different worlds," adds Maryse Fiche. Cathrin Brisken is Assistant Professor at the Swiss Institute for Experimental Cancer Research (ISREC) at the EPF Lausanne. Maryse Fiche works as a Doctor at the Institute for Pathology of Lausanne University Hospital (CHUV). Although the two women come from different backgrounds – basic research and clinical practice – the two have been working together since 2004 within the NCCR "Molecular Oncology ". Their work focuses on a problem that is at once scientifically complex and of major significance to public health: breast cancer. It is one of the most prevalent types of cancer in western industrialized countries. Approximately one in nine women is afflicted by it. In Switzerland 5,000 new cases are diagnosed every year.
Researchers and doctors still know very little about the mechanisms that lead to the occurrence of mammary tumours. One thing is sure however: a hundred years ago these tumours were much less common. At that time, most women did not menstruate until they were 16 and had their first child at 18. "Epidemiological studies have shown that a woman’s risk of breast cancer rises with the increasing number of menstruation cycles before her first pregnancy," explains Cathrin Brisken. The female sexual hormones are the culprits: oestrogen, progesterone and prolactin. After each ovulation, they trigger cell division in the breast glands. However, errors can arise during division, leading to uncontrolled cell growth and the occurrence of malignant tumours.
The Biologist therefore began to explore how hormones influence breast physiology and the role they play in cancer occurrence. The mammary gland is a complex structure, and the "micro-environment in which the cells are located, plays a significant role in cancer occurrence," stresses the researcher. In order to understand the mechanisms involved, the scientists work with genetically modified mice. However, they also use healthy human cells from cosmetic surgery and cancer cells from the operating theatres of the Department of Oncology at the CHUV. "Without the support of Maryse Fiche we would not have access to these cells," emphasises Cathrin Brisken.
Through the research on this breast tissue "we can prove that the hormones affect the breast cells directly and indirectly," explains Cathrin Brisken. "Without hormones, nothing happens in the mammary gland. But if oestrogen and progesterone are present, the cells respond and release a series of substances that influence the adjacent cells." "If we understand what goes on at molecular level in the various tumour groups and sub-groups, we can offer patients more specific treatments," explains Maryse Fiche. This is precisely the aim of the basic research: to offer every woman with breast cancer a specifically tailored therapy.
Working with teams from different backgrounds is extremely important to the success of such projects, because breast cancer research is a multidisciplinary field. "We got together to give the people working in basic research closer contact with practitioners", emphasised Maryse Fiche. "I left medicine fifteen years ago", adds Cathrin Brisken. "However Maryse Fiche comes to the EPF Lausanne regularly and teaches students on the team who, although they have a molecular biology background, don’t know much about breast cancer.
Pathology is also given the attention it deserves. "Molecular classification of frequently occurring breast tumours is increasingly replacing the traditional morphological classification. Studies conducted on mice help us understand the disease," explains Maryse Fiche. The Biologist and the Pathologist are extremely satisfied with their collaboration in the NCCR. In fact they would like to involve oncologists in their work to advance research into the hormone modulation of breast cancer. Interdisciplinary cooperation has a bright future.