A new discovery about how cancer cells prepare the way for tumor growth and spread may lead to new treatments that stop it.
Cancer cells are known to release tiny exosomes which are packed with proteins and other molecules that make the tissue conditions more favorable for tutor progressions in many different ways. The molecules are able to remodel the environment of the cancer cells and are able to insert cancer genes into other cells and signal the immune system not to attack them, all making it easier for tumors to grow and for the cancer to spread to other parts of the body and invade nearby tissue. The spread of cancer is a complex process called metastasis. Researchers now have discovered a protein that controls the release of exosomes from cancer cells to promote tumor progression and metastasis.
This protein is Munc13-4 and it is often largely found in lung, breast, and pancreatic tumors and it is activated by binding to calcium. The researchers found that calcium triggered exosome secretion in aggressive breast cancer cells however when they removed Munc13-4 in the breast cancer cells, calcium no longer caused the cells to secrete exosomes. This was also the case when they replaced Munc13-4 with a mutant form that cannot bind to calcium.
Having greater knowledge about this protein will allow us to produce drugs which are more focused to be able to prevent cancer growth in future and provide a target for cancer therapy.
“Overall, we think that increased expression of Munc13-4, combined with elevated calcium levels, drives enhanced exosome release by highly aggressive cancer cells, and that Munc13-4 is a potential target for therapeutic intervention.” -Prof. Thomas F. J. Martin