Pre-clinical observation highlighted that triple negative (estrogen receptor/progesterone receptor/human epidermal growth factor receptor)-breast cancer cells displayed resistance to retinoids due to the RARγ high expression profile.
The functional consequence of the interplay between c-Myc oncogene expression and the RARγ to RARα/β balance suggests that prevalence of RARγ over-RARα/β expression levels in breast cancer accompanied by c-Myc amplification or over-expression in breast cancer should be predictive of response to treatment with RARα-isotype-specific agonists and warrant monitoring during clinical trials.