Analysing breast cancer cells which were captured as they escaped from a primary tumour has helped provide the optimum clinical evidence to date of a popular theory concerning cancer metastasis.
The research study, below, has been published in Science, which reveals an improved method for plucking tumour cells from blood. It is a technique which could one day enable physicians / researchers to track the lifespan of a cancer without resorting to invasive biopsies.
As stated by Caroline Dive, Cancer Research UK (CRUK) researcher at the University of Manchester (UoM) - "It's very exciting," - and - "It's paving the way for an explosion of studies looking at these circulating tumour cells."
Modern day cancer treatments typically target tumour growth, but it is metastasis, which is the spread of the cells to other tissues that is fatal. Before drug developers can consider producing therapies that can halt the spread of cancer, unfortunately, they first need to properly understand how cells break free from a tumour, enter the bloodstream and subsequently colonise new tissue.
A long and treacherous road
The journey of cancer cells has for sometime puzzled researchers. In other words the cells that make up cancers in epithelial tissue, such as the surface cells of the lung and breast, prefer to stick together and are not best prepared for a rough-and-tumble trip through the bloodstream. However, one theory states that metastasising tumour cells activate pathways that are normally reserved for 'mesenchymal' cells, which are known to move around in developing embryos. Such a pathway has been dubbed the epithelial-mesenchymal transition or EMT and there are companies hard at work trying to develop drugs to target such a switch.
To date majority of the evidence supporting a role for the EMT in cancer spread has originated from animal models. Analyses of tumour cells circulating in the blood has been limited because the techniques employed tend to pick-up only epithelial cells. Dive continues in stating - "It was pioneering technology, but we've always been worried that if EMT was happening, we'd miss the mesenchymal tumour cells this way,"
Therefore, Daniel Haber and Shyamala Maheswaran, both at the Massachusetts General Hospital Cancer Centre, Boston, and their colleagues have managed to develop a new suite of markers to identify tumour cells circulating in the blood. They have tracked the cells and characterised their gene expression in 11 people undergoing chemotherapy for breast cancer.
In their research the team found that when the tumours responded to treatment, the proportion of circulating tumour cells featuring mesenchymal began to drop. Failure of therapy was followed by resurgence of mesenchymal tumour cells.
Going forward, as stated by Haber, they plan to repeat the research in more patients and tumour types. If thereafter the results stack-up, then they could provide drug developers with a list of new targets, as concluded by Klaus Pantel, a cancer researcher at the University Medical Centre Hamburg-Eppendorf, Germany.
Pantel also states that many of the circulating tumour cells have features of both mesenchymal and epithelial cells. This means that the hunt may have to be re-focused on to an intermediate cell type - "The cells that have gone all the way into a mesenchymal state may not be the bad guys after all." Original article available here
As with similar type of cancerous studies, the future potential of such research can be easily solved by nanotechnology.As stated previously, DCN Corp strongly believes it can supersede, by providing a dip controlling process which can accurately provide a life span screening in real-time. Going forward, if you and/or your colleagues are interested in making DCN Corp's alternative process reality - please ensure to contact the company as soon as practicably possible