Source: Cancer Research UK
TRIED AND TESTED blood pressure drug may improve the effects of chemotherapy, US scientists have shown.
Losartan belongs to a class of drugs called angiotensin inhibitors, which have been used as safe blood pressure medications for over a decade.
Dr Rakesh K Jain, director of the Steele Laboratory for Tumor Biology at MGH, said: “Unlike anti-angiogenesis drugs, which improve tumour blood flow by repairing the abnormal structure of tumour blood vessels, angiotensin inhibitors open up those vessels by releasing physical forces that are applied to tumour blood vessels when the gel-like matrix surrounding them expands with tumour growth.”
The team began to look at the physical reasons why chemotherapy drugs might not reach their intended target.
Collagen is a major part of the matrix that surrounds tumour blood vessels and previous studies show that losartan inhibits the formation of collagen.
The latest study, published in Nature Communications, looked at whether losartan and other drugs can affect the forces within tumours that compress and collapse blood vessels. The stresses occur when specialised cells in the tumours known as cancer-associated fibroblasts (CAFs) multiply and produce collagen and another component of the matrix called hyaluronan.
Working with mouse models, the team found that losartan suppressed the activity of CAFs. This inhibited the production of collagen and hyaluronan and prevented compression of blood vessels within tumours.
The study found that combined treatment with losartan and standard chemotherapy delayed tumour growth and extended survival in mouse models of breast and pancreatic cancer…READ FULL ARTICLE