Caring for the Kids

Children affected by cancer are the pivotal focus of Elizabeth Lawlor’s research.

by Lori Oliwenstein

Elizabeth Lawlor spent the first part of her career in medicine as a clinician, caring for children with cancer in Vancouver, British Columbia. And although it has been years since her focus shifted to laboratory science, she has never let the children for whom she is working stray far from her mind.

Lawlor, an M.D., Ph.D., and assistant professor of pediatrics and pathology at the Keck School of Medicine of USC, was recruited to Childrens Hospital Los Angeles in April 2004 to strengthen its Saban Research Institute’s program in sarcomas—tumors of connective tissues such as muscle or bone—and neural stem cells. Specifically, she is trying to understand the genetics of a type of sarcoma called Ewing’s sarcoma—a bone and soft tissue cancer found primarily in children and young adults—and its possible connection to stem cells from the neural crest, one of the early nervous system structures found in a developing embryo.

The evidence that Lawlor and others have gathered seems to point at these specific neural cells as the source of the tumors that plague a small subset of children, who are generally between the ages of 5 and 20 when their cancer is found. People in the second decade of life are most likely to be affected, although cases do occur with older and younger people.

“The central hypothesis about Ewing’s is that the tumors arise from very primitive cells that are embryonic in origin,” Lawlor explains, adding that the hypothesis holds that the tumors are due to cancerous changes in the genetic makeup of primitive stem cells of one kind or another. The front-running culprit is neural crest stem cells.

“We’re studying these neural crest stem cells and the expression of oncogenes in this stem-cell population because we believe that they are central to identifying key biologic features that will lead to novel treatments or cures for the Ewing’s sarcoma family of tumors,” Lawlor explains. “There is now substantial evidence that within a tumor mass, all cells are not the same, that there are cells that represent the very earliest cells of the cancer. I believe that these are the cells that cause disease occurrence, recurrence and, quite possibly, metastasis, and that if we don’t kill these critical stem cells, the tumor will come back.

“In fact, I think that this is why Ewing’s sarcoma has such a high rate of resistance to treatment and recurrence after treatment. And that’s why we’re focusing on this in my lab.”

Actually, she says, the central reason behind the work is the children who would be helped by the research.

“Pediatric diseases tend to be overlooked in larger institutions, but not here,” she says. “Here, there is a connection between the clinical and the research teams that makes it so much easier to take scientific knowledge and advances from the bench to the bedside and back again. And that’s good for everyone.”