Dr. Ramaswamy Discusses Tumor Heterogeneity

Sridhar Ramaswamy, MD, Tucker Gosnell Investigator and Associate Professor of Medicine, Massachusetts General Hospital Cancer Center, Harvard Medical School, Broad Institute of Harvard & MIT, and Harvard Stem Cell Institute, explains that every tumor, no matter what type, displays a certain degree of heterogeneity.

Heterogeneous cells can vary on both a molecular and genetic basis. Some cells differentiate on a cellular level by displaying various patches on the cell surface that are different than the rest of the cell. Cellular disparity may contribute to tumor recurrence and therapy resistance.

When examining the cells, different classifications arise. Some are pre-apoptotic and are near the point of programmed cell death; this type will not cause issues in the future. Other cells are senescent, which do not proliferate. The most interesting set are the sleeping or dormant cells, which can be implicated in drug tolerance. Sleeping cells are particularly interesting because of their ability to move in and out of the dormant state.

Ramaswamy notes that understanding the mechanism of heterogeneity may help understand the dynamics of tumor growth, which could lead to a more sustainable drug response.