Cancer May Have Its Own Stem Cells
Not one, not two, but three brand new studies point to growing evidence that the reason cancer is so stubbornly resistant to treatment is that it has its very own stem cells. These cells may allow the cancer to start growing again. Speaking to a HealthDay reporter, Dr. Max Wicha, director of the University of Michigan Comprehensive Cancer Center, commented on one of the studies, which was published online in the journal Nature."Cancer stem cells are still controversial, but with progress in studies like these, it's less about whether they exist and more about 'what does this mean?'" he said.
One study involved mice with a common and particularly lethal form of brain cancer. Lead researcher Luis Prada of the University of Texas Southwestern Medical Center in Dallas and colleagues genetically engineered mice so they would develop the cancer. After that they created a "transgene" that would only to become active in stem cells in healthy adult brains and they gave the transgene a green fluorescent marker. Finally, they added a virus gene that would self-destruct if treated with a drug called acyclovir. When they put the transgene into the mice with tumors, cells in the tumors were green.
HealthDay quotedPrada as saying, "The next obvious question was: Since the 'transgene' was designed to be active in stem cells, might these be stem cells?" To answer their question, the research team gave acyclovir to the mice. "And when we did that, the tumors stopped growing," Prada said.
"It's interesting that all the studies came to the same conclusion with different types of cancer," Wicha told HealthDay. He added that early clinical studies are already in the works using drugs to target the cancer stem cells.