A Novel Approach
CHORI Research Offers New Clues to Tumor Growth
This subset of larger tumors – about 5 percent of all hemangiomas – can be destructive to the cartilage in the nose and ears, or result in permanent visual deficit, depending on where they grow; discovering what causes them is the first step in figuring out how to prevent them.
In a new report in the March issue of Pediatrics, however, Dr. Lammer and his colleagues at the University of California at San Francisco, have suggested a new thought: that in some of these hemangiomas, the cause of the problem derives from cranial neural crest cells, rather than from the cells that line the blood vessel walls.
The basis for this new theory comes from certain observations Dr. Lammer and his colleagues made through analyzing photographs from nearly 300 patients with facial hemangiomas.
“What you see is that among a certain group of hemangiomas, the blood vessel tumor reaches a border, and then just stops there – consistently and reproducibly among a variety of kids,” says Dr. Lammer.
The boundaries at which this subset of facial tumors stop parallel exactly embryonic boundaries of facial development.
Says Dr. Lammer, “These tumors are respecting boundaries that can only be determined by the end of the first month after conception. They grow to the edge of a segment that has basically been defined since the embryo stage of the baby. This is a clue that in certain hemangiomas, the thing that has gone wrong may be within the cranial neural crest cells, even though they do not contribute the cells that form the blood vessel wall.”
Cranial neural crest cells are suspect because they play a critical role in embryonic development. Their potential involvement in hemangioma pathogenesis suggests the need for alternative approaches to hemangioma research that involve studying the molecular and cellular processes that regulate embryonic facial development.
“It should redirect some of the research to focus on cells other than just the blood vessel cells,” explains Dr. Lammer. “That’s the bottom line. We’re trying to get people to look for abnormalities in other cell types than just blood vessels.”
The new publication goes a long way toward making that redirection possible. In addition, the research was presented at the first National Institutes of Health (NIH) conference on infantile hemangiomas, Infantile Hemangiomas: Current Knowledge, Future Directions (April 7-9, 2005).
“This was the first time ever that a group of people got together for a two-day conference exclusively focused on infantile hemangiomas,” says Dr. Lammer.
Organized by one of Dr. Lammer’s UCSF colleagues, Ilona Frieden, MD, the conference represents a fresh approach in hemangioma research, with the results of the new study leading the way toward the possibility of unraveling hemangioma pathogenesis. A summary of the conference was published in Pediatric Dermatology 2005 Sep-Oct;22(5):383-406.
Monday, May 16, 2011 11:33 PM