First steps towards targeted liver cancer therapy
US researchers are developing a new form of immunotherapy, based on a 'monoclonal antibody' that appears to be able to block the growth of both mouse and human liver cancer cells in the laboratory.
Monoclonal antibodies are proteins that have been specifically modified to stick to other proteins on the surface of cancer cells.
This can interfere with the cell's function, or alert the body's immune system to the presence of a tumour.
The team initially discovered that a protein called 'platelet-derived growth factor receptor-alpha' (PDGFRa) was found at higher levels on the surface of liver cancer cells than on normal cells.
So the team developed a monoclonal antibody that could stick to PDGFRa.
Using cells grown in the laboratory, they found that the antibody could block the growth of cancer cells, and cause them to die at a much higher rate than normal cells.
Dr Satdarshan P Singh Monga, associate professor at the university's division of cellular and molecular pathology, commented: "We are very excited because this is the first targeted therapy for liver cancer.
"We now have identified a pathway that appears to be overly active in more than 70 per cent of the cancers we examined and, when targeted, leads to significant reduction in tumour cell proliferation and survival."
Dr Monga also pointed out that the therapy does not seem to adversely affect normal liver cells and concluded that the monoclonal antibody "is a highly targeted treatment for this disease".
High levels of PDGFRa have also been detected in other types of cancer, including brain, stomach and prostate tumours, as well as skin cancer, ovarian cancer and leukaemia, and the researchers suggest that the findings could therefore have implications for other cancers.
The research is published in the journal Molecular Cancer Therapeutics.