Stem Cells and the Development of Sebaceous Glands

For the first time, researchers from the University of Copenhagen have studied and outlined the development of sebaceous glands in the skin. The study, published yesterday in Nature Cell Biology, provides greater insight into skin development and maintenance and into the way cancer mutations affect the behavior of stem cells.

“We demonstrate for the first time ever how the sebaceous glands that contribute to the natural moisture of the skin are formed and how they are maintained throughout life by stem cells,” says first author Marianne Stemann Andersen. “This knowledge may be transferred to individuals with sebaceous gland conditions, e.g., acne or very dry skin.”

The researchers found that when a stem cell divides and gives rise to two daughter cells, it leads to the formation of two new stem cells more often than to the formation of mature sebaceous gland cells. This way, the sebaceous gland continues to grow until it reaches its mature size. At this point, the behavior of the stem cells changes, and new cells only emerge when mature sebaceous gland cells burst to release their moisturizing lipids on the skin.

But when the researchers introduced a common and specific cancer mutation, the behavior of the stem cells changed. Surprisingly, the mutation did not cause cells to divide more often; instead, it gave them the tendency to generate more stem cells rather than maturing sebaceous gland cells when they divided.

“In this case, the result is a sebaceous gland, which—similar to tumors—continues to grow,” says senior author Kim Jensen. “We hope this knowledge can contribute to the design of better cancer treatment.”

According to coauthor Svetlana Ulyanchenko, the previous belief was that this mutation causes cells to divide more frequently. But the new research shows that its effect on the frequency of cell division is actually quite low.

“Instead, stem cells with the cancer mutation are much more likely to divide into two new stem cells than generating mature sebaceous gland cells. This explains why the sebaceous gland continues to grow after we introduce this mutation to the skin,” Ulyanchenko says. “In connection with cancer therapies that target cells that divide frequently, this means that cancer cells and normal cells are just as likely to be targets of the treatments. If we are able to determine what controls how often cells divide when mutated, we may be able to develop therapies that specifically affect cancer cells.”