Courtesy Stevenfruitsmaak via Wikimedia CommonsWhen a cancer cell (a tumor) appears in a particular organ or area of a body, it somehow signals the body's immune system to back off and leave it alone. This allows the cancerous tumor to grow and eventually metastasize to the lymph nodes and other parts of the body. It's as if the cancer grants itself a sort of diplomatic immunity against the body's natural antibodies from interfering with its destructive undertakings.
Now, researchers have found a drug that switches off this "don't touch" warning and allows the cancer to be diminished or entirely destroyed. And it works for several types of cancers, including those affecting the brain, liver, colon, breast, ovary and prostate.
A protein called CD47 is present in human blood cells and prevents those cells from being attacked by the body's immune system. The protein attaches to the surface of the blood cells and signals to the immune system that the blood cells are "okay" and shouldn't be destroyed. About ten years ago, biologist Irving Weissman and researchers at Stanford University's School of Medicine noticed higher levels (up to 3x more) of the same "don't touch" protein were present in leukemia cells, a blood disorder. The surprised Weissman realized that the blood cancer was co-opting the body's own defense system to work against itself, thereby stopping any attacks on the cancer. This left the cancer unmolested and able to grow and spread. After further testing, Weissman and his colleagues subsequently discovered that CD47 levels in many other cancers were also higher than levels in normal cells.
"What we've shown is that CD47 isn't just important on leukemias and lymphomas, it's on every single human primary tumor that we tested.“
The Weissman lab has now developed a promising drug that switches off this "don't touch" signal in cancer cells giving the body's immune system the green light to go after them. The drug has been tested in the laboratory using petri dishes containing treated and untreated cancer molecules. Immune cells (macrophages) were present in each sample. In the untreated sample, the macrophages ignored the cancerous molecules, while they readily attacked those treated with the anti-CD47 drug. In later tests, a variety of human cancer tumors were placed into lab mice and left to grow for two weeks. After the tumors grabbed hold, they were treated with the anti-CD47 therapy and the tumors shrunk considerably or disappeared altogether.
"The microenvironment of a real tumor is quite a bit more complicated than the microenvironment of a transplanted tumor," Weissman said, "and it's possible that a real tumor has additional immune suppressing effects."
The biologist is confident that the research will eventually move into human clinical trials within the next two years.
OK, I think the history of infectious disease is fascinating, and I'm a sucker for many things gross, but I'm still a bit surprised that I loved this little quiz game about the bubonic plague as much as I did. You gotta play. Did you love the animation and sound effects as much as I did?
New studies contradict the idea that duct tape is effective in curing warts. You might remember all the hubbub a few years ago that said the best way to get rid of warts was to put a piece of duct tape on the warty area and they would soon be dissolved away.
That study was done in 2002, but a new study done over a larger group of subjects showed that duct tape worked only 21 percent of the time in dissolving warts.
Warts are caused by a virus that hangs around in the outer layers of our skin. They’re in a place that’s hard for our bodies immune system to get its antibodies to attack the virus. The original theory behind the duct tape treatment concept was that rubber on the sticky side of the duct tape would irritate the skin enough to stimulate antibodies to go to the wart and kill it off.
But the new study found that duct tape was no more effective in treating warts than moleskin bandages, which are a cotton tape bandage similar to a Band-aid.
According to the experts in the field, the best way to treat warts is to use over-the-counter topical treatments that contain salicylic acid. Doctors will sometimes use laser therapy or liquid nitrogen to zap especially pesky warts. Without any treatment, most common warts will clear up on their own within two years.