CARS imaging reveals FFAs impacts on M109 cells are observable in mammary cancer. (A) FFAs induced lipid accumulation and reduced cell-cell adhesion in human mammary cancer MCF-7 cell line. Upper panel: MCF-7 cells on day 0; lower panel: MCF-7 cells after 4 days of treatment with CM FFAs. (B) Lipid-rich cancer cells of a rat mammary carcinoma have disordered organization. Upper panel: lipid-poor rat mammary carcinoma; lower panel: lipid-rich rat mammary carcinoma. Positive CARS contrasts arise from lipid-rich membrane and intracellular lipid. Negative CARS contrasts indicate lipid-poor nuclei. Scale bars: 25 μm.