Dr. Mina Bissell has spent the past thirty years questioning the status quo of our understanding of the development of cancer.
Traditional thinking was that a single cancer cell inside a single cell is enough to cause cancer, but to Bissell this didn’t make sense as the human body is made up of somewhere between 10 and 70 trillion cells and if even 0.000001% of these cells were cancerous you would be a walking tumor.
Her experiments have led her to the conclusion that humans aren’t just constantly filled with cancerous cells because of context and architecture. One of her early experiments focused on a type of chicken cancer that others had been able to isolate and then re-grow in adult chickens and cultures, but her team would show that in a chicken embryo no cancer would develop. These findings led Bissell to conclude that the microenvironment in which the cancer cells reside dominates the cancer genes–it tells the cancer cell what to do.
In another study looking at mammary glands, Bissell removed the specific functioning cells that created milk from mice and placed these cells in a dish and within a few days the cells had lost their structure and no longer could produce milk. To support her conclusion that context influences cell structure and function she reintroduced an extracellular matrix, or ECM, to the cells in the dish and was able to signal the cells to make the same structures as before and the cells reformed and created milk in the dish.
By using an ECM Bissell was able to revert malignant cells to normal phenotypes showing that abnormal genomes should be capable of becoming “normal” if tissue architecture is restored. Her overarching conclusion is that growth and malignant behavior are regulated at the level of tissue organization, and tissue organization is dependent on the ECM and the microenvironment.
The insight Bissell and her lab continue to provide the medical community in terms of the development and treatment of cancer cells may one day lead to new ways of treating existing cancer and possibly prevention.
Written by Angela Goad