While not yet invasive, this activity could explain some reoccurrence and lowers the barrier for future invasive growth, according to Journal of Cell Biology paper.
Early-stage breast cancer that has not yet invaded the surrounding tissues may already contain highly motile cells, which brings the tumor one step closer to metastasis, report researchers at the Salk Institute for Biological Studies.
In their study, the Salk researchers used a tissue culture model that recreates the ducts of the mammary gland. They embedded human cells, isolated from breast tissue, in a 3-D matrix that mimics their natural surroundings. These cells spontaneously develop into so-called acini, hollow structures resembling tiny milk ducts.
Then they turned on the ERK1/2 MAP kinase pathway, a signaling cascade frequently activated during the development of tumors and watched in real time as breast cancer cells learned how to “walk.” “We quickly realized that there was a significant cell movement, which was quite surprising,” says lead author Gray Pearson, Ph.D., a postdoctoral researcher in the molecular and cell biology laboratory at the institute. “Within 24 hours, a large number of these spheres had lost their organization, and the cells started to dance around.”
While dangerously invasive cells can squeeze through the basement membrane and make a run for the surrounding tissue, motile cells still could not escape the confines of the ERK-activated acini. “But the acquisition of motility prior to invasion presumably lowers the barrier for future invasive growth,” explains Dr. Pearson.
The research is published in an upcoming issue of the Journal of Cell Biology.