One deadly and defining characteristic of cancerous cells is that they divide in an unregulated manner, allowing the tumor to grow larger and become more disruptive to the body. Researchers at Mayo Clinic in Florida, led by Panos Anastasiadis and Antonis Kourtidis, have identified a critical difference between cancerous cells and noncancerous cells that could lead to a treatment therapy that corrects the root cause of the cells’ cancerous behavior. A treatment could turn off this rapid cell division so that cancerous cells no longer grow at an accelerated rate and are effectively transformed back into normal, noncancerous cells. The researchers may have effectively figured out how to apply the brakes to cancer.
Cancer researchers for some time now have been focusing on the proteins responsible for cell-to-cell adhesion, since these proteins are responsible for signaling when cell division should start or stop based on the detection of neighboring cells. An important discovery of the Mayo Clinic researchers was that for two of these adhesion proteins, E-cadherin and p120, their behavior was different in normal versus cancerous cells. After further examination, the researchers found that the difference between the “good” version of these proteins (proper regulators of cell growth) and the “bad” version (promoters of tumorigenesis) was the presence of the protein PLEKHA7. In the presence of this protein, a PLEKHA7-microprocessor complex binds to the apical region of epithelial cells and regulates the production of a set of microRNA that triggers the “good” behavior of E-cadherin and p120. In the absence of the PLEKHA-7 protein, the “bad” behavior is expressed and the cells are cancerous. By injecting these cells with the PLEKHA-7 protein or the microRNA chains that they produce, the researchers were able to make the tumorigenic behavior of cells disappear.
This method has been proven successful in vitro in human breast and bladder cancer cells, and the findings are published in Nature Cell Biology. Researchers are now looking into the best delivery method for this therapy, as well as considering how this new knowledge could be leveraged for more definitive cancer diagnostics.
Study in Nature Cell Biology: Distinct E-cadherin-based complexes regulate cell behaviour through miRNA processing or Src and p120 catenin activity…