How exactly does RNAi help in fighting against cancer gene ?
Have you read this wiki article yet? It's got some nice information and should explain a great deal about RNAi.
AFAIK, there are no approved therapies that use RNAi against any disease, including cancer.
I watched a Ted-ed video about it which says that this method can be used for such purposes.
I read an article about Telomerase mutation that can cause tumors to grow and spread quickly. Oddly enough if Telomerase activity is healthy it slows the aging process.
People are certainly trying to develop such therapies and they can, in principle, be used against cancer, but to date no one has shown such therapies to be safe and effective in clinical trials. There are some promising therapies in clinical trials that may turn out to be safe and effective, but no such therapies have been approved by the FDA yet.
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