By Janet Fang
Posting in Cancer
Using DNA extracted from healthy prostates, scientists have designed a vaccine that uses the immune system to attack cancerous cells, curing 80% of the test mice.
UK and Mayo Clinic researchers have created a vaccine that cured prostate tumors in mice.
By using the immune system to attack tumors, this novel ‘immunotherapy’ treatment doesn’t rely on toxic chemotherapy or radiation.
It contains bits of DNA from the organ where tumors can develop – so it’s like a vaccine, which contains weakened viruses to be destroyed and remembered by the immune system. But unlike a traditional vaccine, this therapeutic vaccine doesn’t prevent disease… it treats it.
The researchers assembled genetic snippets from healthy human prostate tissue into a DNA library, and then the DNA bits were inserted into a swarm of viruses. This then was introduced intravenously into mice.
Then their tumors shrank, and 80% of them were cured with 9 virus injections. The researchers say the technique could be applied to many other kinds of aggressive cancers.
So all infections, allergens, and tumors have unique protein tags – called antigens – that trigger a response from the immune system. The prostate DNA made the virus vector produce a wide range of prostate antigens.
After exposure to the mutated viruses, the mouse immune systems recognized the antigens expressed in the virus and produced an immune response that attacked the prostate tumors.
“By expressing all of these proteins in highly immunogenic viruses, we increased their visibility to the immune system,” says study author Richard Vile from Mayo Clinic. “The immune system now thinks it is being invaded by the viruses, which are expressing cancer-related antigens that should be eliminated."
There were no observed side effects and no trace of autoimmune disease in the mice; their immune cells attacked only cancerous cells.
And that’s possible here because the DNA library was harvested from the same organ as the tumor, he explains. The immune system ‘self-selected’ the cancer antigens to respond to and didn't react against other healthy parts of the body.
Clinical trials could begin within the next 2 years.
Just a couple months ago, the FDA approved Bristol-Myers Squibb’s ipilimumab, or Yervoy, an immunotherapy drug for advanced melanoma patients.
The study was published yesterday in Nature Medicine.
Image: syringes by alvimann via morgueFile
Jun 19, 2011
It's not clear how the mice immune system knew to "self-select" only the cancerous antigens to attack, especially after being injected with DNA from healthy human prostates. The researchers started with DNA from *human* prostates, and injected them into mice with prostate tumors. Are these special mice that have DNA from humans already? Did their systems view the human DNA as invasive? Injecting human DNA into humans to provoke an immune response may not work as well as injecting human DNA into mice. It's just not clear to me how this works.
This approach is so far superior to the chemo/ radiation treatments that many people would be happy to take a risk on it rather than have to wait two years. Can anything be done to fast track its availability?
Since it sounds it work, why wait for two years, am willing to volunteer, because I have prostate cancer stage 4, have undergone radiation, chemo etc, although am not bed ridden now,and I go to work everyday, but still feel some side effect from my medications, from the Philippines.firstname.lastname@example.org
This is great news even though we have to wait for 2 years for trail results. I wonder when it will eventually be readily available worldwide. I hope it will be able to address all sorts of cancer. I am taking tumeric regularly but not sure of its efficacy but short of alternatives, I am going in the ayurvedic way.
Can you share that vaccine to us? for my mom..my mom has stage four breast cancer..im from the philippines (032)2731889..mitch
Can you share that vaccine to us? for my mom..my mom has stage four breat cancer..in the philippine (032)2731889..mitch
so then humans just need animal DNA to replace in the same manner, but this might be a mistake in writing/typing.. It would make more sense to use mouse DNA on mice in the first go around.
I'm so sorry to hear about your mother. This vaccine, unfortunately, won't be available for testing on humans for at least another two years.