Protein that prevents spread of cancer

In a major breakthrough that might increase the survival rate of cancer patients, an American research team has identified a protein which inhibits spread of affected cells to other parts of the body from a carcinogenic tumour.

Researchers at Children's Hospital Boston have isolated a protein called prosaposin which stops metastasis or the spread of cancer cells to other parts of the body, by blocking the growth of blood vessels.
Assistant Professor Randoph S Watnick here found that metastatic tumours prepare landing places in distant organs for their migration, by secreting certain proteins that encourage tumour growth and attract feeder blood vessels.
Now, he and his colleagues show that non-metastatic tumours secrete a protein called prosaposin -- which inhibits metastasis by causing production of factors that block the growth of blood vessels. "Prosaposin, or derivatives that stimulate p53 activity in a similar manner in the tumour stroma, might be an effective way to inhibit the metastatic process in humans," says Watnick in his findings, which were published in the online edition of the Proceedings of the National Academy of Sciences during the week of June 22.