hiv may hold key to cancer cure
HIV may hold key to cancer cure PRINT FRIENDLY EMAIL STORY The World Today - Tuesday, 15 February , 2005 12:21:00 Reporter: Karen Barlow ELEANOR HALL: To an extraordinary good news twist on the disease which has been devastating communities around the world for decades, AIDS.
Scientists have discovered that HIV, the virus which causes AIDS, could in fact hold the key to curing cancer.
A research team from the University of California has disabled the AIDS causing parts of HIV and reprogrammed it as a cancer killer.
And while it may be several years before the technique can be used in humans, this gene therapy is proving to be successful in research on mice, as Karen Barlow reports.
KAREN BARLOW: Since the arrival of HIV in the later part of the last century, the virus which causes AIDS has cut a swathe through the world's population.
Last year alone a record 3.1 million people died of AIDS, mostly in developing nations where anti-retroviral drugs are neither fully nor cheaply available.
It has also caused fear, despair and misunderstanding.
Any cure is a long way off and researchers are focusing efforts on a preventative vaccine or improving the lives of HIV positive people through combination drug therapies.
But other researchers have been impressed by the virus's tenacity and killer instinct.
Elizabeth Withers-Ward from the Los Angeles AIDS Institute at the University of California says HIV has proven the best carrier in cancer gene therapy trials on mice.
ELIZABETH WITHERS-WARD: It's the perfect candidate in that it allows infection of, and integration of human cells, because it has the right machinery. It has the ability by the virus envelope or the outside of the virus, decorated with a protein, and that's, depending on what that protein is, it uses a certain cell on the outside of its host protein to bind and then get in.
So in this case we've changed the envelope to bind to antibodies and then, the antibody, once bound, will hone to the type of cell that it binds to.
KAREN BARLOW: The process would not led to an HIV infection, as Elizabeth Withers-Ward says the virus is stripped of its dangerous AIDS causing parts.
ELIZABETH WITHERS-WARD: We have taken out about 80 per cent of the HIV sequences and in that way, disabled the virus. And what we've left is the little bits that are necessary to get the DNA into the cell and then get it into the cell DNA.
It's a really profoundly important thing in gene therapy. It really is, because you can actually, in this case, specifically target the population of cells. It's the first time anyone's done that. I mean it's really cool.
KAREN BARLOW: In the California trials, the reprogrammed viruses bound themselves to lung cancer cells. Elizabeth Withers-Ward says they could be reprogrammed to release their load of therapeutic genes on all types of cancer cells.
ELIZABETH WITHERS-WARD: It's a tremendous powerful system and tool, precisely because you've modified the envelope to bind to antibodies and then, depending on what antibody you've put in there, it could bind to a lung tumour cell, a kidney tumour cell, you know, a brain tumour cell.
So, you could imagine, I mean there are endless possibilities of how this might be used.
KAREN BARLOW: And it'll certainly improve the reputation of HIV?
ELIZABETH WITHERS-WARD: I think so. I mean, if people would sort of be challenged with thinking about that idea seriously in terms of therapy, a lot of testing would be done and I think then people might feel safer. So, it's taking a very negative virus as it were, a virus with a very negative potential and turning parts of it into a very positive thing
