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Holy smoke. I heard of this idea but I didn't think it would work. Holy jumpin' mackerel!

This is, of course, only in vitro, where a number of things seem to work that end up killing the patient in vivo. But it is very promising. That it is a mechanism for apoptosis as well as gene suppression is even more exciting - there are a number of apoptosis-activators currently in clinical trials but I don't know of any that sound this promising. Oncology isn't a magazine known for hype or journalistic hysteria, either.

For those who care, the reason AIDS patients are in this is that they are a conveniently immune-suppressed population that is willing to act as human guinea pigs. I don't care how they got that way, I'm just glad they're volunteering. That is always the most difficult hurdle for treatments involving gross somatic effects, getting something approximating the human organism to act as a disease model for toxicity studies and projected dosages. Unless I'm missing something pretty big this is not a cure for AIDS, it's a potential cure for tumor cancers.

Yes, real tissues containing real cells pose challenges for a cancer drug that a test tube full of isolated cells does not. You have to get effective levels of the drug to all the cancer cells without hurting too many of the normal cells in which the cancer is embedded. And you have to get past enzymes and other things that can deactivate the drug.

Why discuss the HIV infected with RNAi? Simple. RNAi is a naturally occuring mechanism in the body that shuts of DNA when introduced to a double-straned RNA completment of that DNA. For instance in the case of HIV, which inserts it's genome into the cellular genome, we know the sequence of the mRNA used by HIV to manufacture, say a structural capsid protein, now if a complement of this mRNA can get into the cell, it will bind with this mRNA, creating a doublestrnded RNA molecule. Here's the RNAi part - special enzymes recognize this this doublestanded RNA and then they actively serach out the DNA complement and permantly shut if this gene. No structural protein gene - no virus.

It would work similarly in cancer to stop the production of certain cancer associated proteins.