The invention generally relates to methods for determining aggressiveness of a cancer and treatment thereof. Certain aspects of the invention provide methods that involve conducting an assay on a lipid droplet in order to detect an amount of a biomarker within the lipid droplet, and determining aggressiveness of a cancer based upon the amount of the biomarker within the lipid droplet. Other aspects of the invention provide methods for treating a cancer that involve administering an agent that blocks storage of cholesteryl ester in a lipid droplet.
