Ovarian Cancer Linked to Stem Cells

Ovarian Cancer Linked to Stem Cells

Ovarian cancer has now joined the increasingly long list of cancers which have a stem-cell like “side population” of continuously multiplying cells. In a recently published study described on Reuters, scientists injected these cells into mice, who then developed tumors. The researchers hope that information about a specific patient’s cancer stem cells may eventually be an important component of diagnosis and treatment.

Private hESC Lines More Used Than Public

Private hESC Lines More Used Than Public

One of the ongoing arguments about federal support for embryonic stem cell research is whether or not the approved lines are as useful as un-approved lines. A Bloomberg article gives support to the idea that the federal lines are insufficient for really good research. According to the story, since 2003 246 stem cell samples have been sent to laboratories from the federal stem cell bank; in contrast, Harvard University has sent out 667 samples in the same time period. A stem cell researcher who was quoted said that the Harvard cells grow more rapidly than the federal cells, which may have been damaged by their age. They are also freer of genetic abnormalities. Basically, if you try to grow a stem cell over multiple generations, small errors will add up.

Another concern raised in the article is the fact that the stem cells approved for research may not be genetically very diverse; since they were obtained from left-over in-vitro fertilization embryos, they are more likely to represent a well-off white population than minority groups. Asian and other countries are beginning to supply stem cell lines to American researchers, but of course they can’t be purchased with federal dollars.

One other item was interesting; cells from Harvard were in at least one case obtained at no cost, compared to $10,000 from the government. I tried to find out from the Harvard website if this was usual, but there are no places to go to if you want stem cells—you must have to know somebody!

Hair Today, Muscle Tomorrow

Hair Today, Muscle Tomorrow

That headline is a bit misleading, because it’s not actually about hair, but there’s more news on stem cells from hair follicles. (Almost all the rest of the news is about the upcoming Senate vote—lots of people have opinions.) According to a press release, Researchers at the University of Pennsylvania School of Medicine have been able to differentiate stem cells obtained from scalp tissue into several kinds of cells. Hair follicles are already known to be a source of stem cells; in this research, the scientists looked at the stem cell niche, known as the hair follicle bulge. (Once again, the niche is showing its importance as part of what influences stem cell development.) They were able to obtain a new kind of stem cell from the scalp tissue and then cultured it under the same conditions as they would embryonic stem cells. The cells grew into masses called hair spheres, from which stem cells were isolated.

The researchers were then able to differentiate them into nerve cells, smooth muscle cells, and melanocytes (skin pigment cells), among other types by growing them on a medium with appropriate growth factors. The most successful of these was the smooth muscle cell type; 80% of the differentiated cells grew into smooth muscle tissue. In contrast, only 10% of the cells on the nerve medium grew dendrites and expressed neuronal proteins. They also produced neurotransmitter glutamate but not dopamine.

Besides demonstrating the multipotency of stem cells from the follicles, this research also shows that embryonic stem cell type medium can be used on non-embryonic stem cells to cause them to grow. At this point if I were a scientist I’d be using embryonic growth medium whenever possible—and if I were a biotech company, I’d be developing a scaffolded or multidimensional culture. It seems like the more that is learned about stem cells, the more important and complex the involvement of the environment is.