Cardiovascular conditions leading to heart attacks and strokes are treated separately from common cancers of the prostate, breast or lung.
But it turns out these conditions involve some of the same critical mechanisms at the molecular level.
This provides clues to more effective therapies for cancer and cardiovascular diseases, but needs researchers in these fields to collaborate.
The European Science Foundation (ESF) recently organised a workshop that highlighted the progress already made in understanding key common mechanisms underlying both disease categories.
The workshop considered one of the most important molecular processes common to many cancers and cardiovascular diseases: the pathway known as the endothelin axis.
The endothelium is the thin layer of cells lining every blood vessel of the body.
This layer separates the blood from the vessel-walls and the smooth muscles, the contractions of which restrict and control blood flow.
These muscle contractions are controlled by proteins called endothelins manufactured by the endothelium cells.
Too many endothelins restrict blood flow, causing hypertension (high blood pressure) and contributing to other conditions such as acute coronary syndrome and stroke.
Some endothelins are signalling molecules that promote growth and retard apoptosis (cell death) which eliminates cells.
Some tumour cells, for example in ovarian carcinoma, exploit endothelins to suppress their death while they migrate to other parts of the body in the metastasis process, enabling the tumour to spread, usually with fatal results.
Understanding the endothelin axis and its role in cancer and cardiovascular disease is now growing as a result of collaboration between these medical research fields.
The role of endothelins had until recently been studied mostly in the context of cardiovascular disease rather than cancer.
Conversely, angiogenesis, which is the sprouting of new blood vessels from existing ones, has been studied mostly for its role in tumour growth, but not as a possible therapy for heart disease through developing new blood vessels to replace damaged ones.
Yet the same underlying molecular pathways are at work in both cases, with potential for synergy between the two research camps.
The workshop heard how the overlap between cancer and cardiovascular disease was of concern for research and development of new therapies and had practical considerations for immediate treatment.
Giovanna Trivella, the ESF workshop's convenor, from the Institute of Clinical Physiology at the National Research Council of Italy (CNR) in Pisa, said: 'Many patients that receive chemotherapies develop heart failure symptoms and the cardiologists have to interact with the oncology (cancer) specialists to make complex therapeutic decisions.' There has also been an overlap for many years in imaging technologies that play a role in studying both types of diseases in laboratories.
Positron electron tomography has been used in both fields to produce images of the body region, such as a tumour, under study.
Trivella added: 'The Positron Electron Tomography Laboratory has been used to study the field of cardiac microcirculation and ischemic myocardial metabolism and yet later on it also became a powerful tool in oncological diagnostic procedures.' There is also overlap between cardiovascular disease and cancer at the level of gene expression and regulation within cells and in particular the role of small RNA molecules called micro RNAs.
These molecules do not perform the role of RNA as traditionally understood in carrying genetic information from the DNA of genes to the protein factories called ribosomes.
Instead they control the expression of genes.
When this goes wrong, inflammatory processes can be triggered that increase the risk of cardiovascular diseases and cancers.
Giuseppe Rainaldi, the co-convenor of the workshop, said: 'The future direction is to investigate whether and how the different gene networks regulated by micro RNAs are organised as a whole.
'These studies will be necessary to understand complex biological processes and to approach micro-RNA-based therapy in a more efficient way.' The ESF workshop helped kick-start the studies by emphasising the need for greater integration between imaging technologies and molecular biology and for more fundamental research in physiology.
The ESF workshop, Molecular Signalling in Cardiovascular and Oncological Diseases: Similar and Shared Pathways, was held in Pisa, Italy, during July 2008.
