The primary focus of the Weeraratna laboratory is the study of how melanoma spreads, or metastasizes. The progression of melanoma from early to late stage involves a series of signaling changes within the cell, often described in terms of "pathways." In particular, Weeraratna focuses on the non-canonical Wnt signaling pathway and how changes in genes and their protein products involved in this pathway can lead to changes in how malignant cells multiply, move throughout the body, and invade other tissues.
In a related course of study, Weeraratna is also extremely interested in exploring how changes in the microenvironment contribute to both tumor progression and therapy resistance. These changes may be induced changes such as chemotherapy or irradiation, or more "natural" changes such as hypoxia and aging. As an example, melanoma incidence is increased in elderly patients, who also have a worse prognosis, and this could be due to a number of age-related factors, such as decreased immunity, but may also be due to changes in the aging microenvironment. Using melanoma cells and both young and old normal skin cells as a model, Weeraratna is trying to unravel just what these changes may be, and how they affect tumor progression.