Biologists discover rotational motion of breast cells, required to avoid malignancy
In a study that holds major implications for breast cancer research as well as basic cell biology, scientists with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) have discovered a rotational motion that plays a critical role in the ability of breast cells to form the spherical structures in the mammary gland known as acini. This rotation, which the researchers call “CAMo,” for coherent angular motion, is necessary for the cells to form spheres. Without CAMo, the cells do not form spheres, which can lead to random motion, loss of structure and malignancy.
“What is most exciting to me about this stunning discovery is that it may finally give us a handle by which to discover the physical laws of cellular motion as they apply to biology,” says Mina Bissell, a leading authority on breast cancer and Distinguished Scientist with Berkeley Lab’s Life Sciences Division.
Bissell is a corresponding author of a paper describing this work in the Proceedings of the National Academy of Sciences (PNAS), along with Kandice Tanner, a post-doctoral physicist in Bissell’s research group. The PNAS paper is titled “Coherent angular motion in the establishment of multicellular architecture of glandular tissues.” Other authors were Hidetoshi Mori, Rana Mroue and Alexandre Bruni-Cardoso, also members of Bissell’s research group.
Healthy human epithelial cells in breast and other glandular tissue form either sphere-shaped acini or tube-shaped ducts. The cell and tissue polarity (function-enabling spatial orientations of cellular and tissue structures) that comes with the formation of acini is essential for the health and well-being of the breast. Loss of this polarity as a result of cells not forming spheres is one of the earliest signs of malignancy. However, despite all that is known about cell morphogenesis, the fundamental question as to how epithelial cells are able to assemble into spheres that are similar in size and shape to organs in vivo has until now been a mystery.
Kandice Tanner (left) and Mina Bissell led a research team that discovered a rotational motion in human breast cells - dubbed CAMo - that is critical for healthy cell development. (Photo by Roy Kaltschmidt, Berkeley Lab)
“We’ve discovered a novel type of cell motility where single cells undergo multiple rotations and cohesively maintain that rotational motion as they divide and assemble into acini,” says Tanner. “We’ve also demonstrated that this CAMo is a critical function for the establishment of spherical architecture and not simply a consequence of multicellular aggregates. If CAMo is disrupted, the final geometry is not a sphere.”