. . . . . . . "[Higher differentiated, estrogen-dependent, estrogen receptor (ER)-positive (ER+) mammary carcinoma cells have been found to contain relatively high levels of RAR-alpha and to be responsive to retinoids, whereas most undifferentiated, estrogen-independent, ER-negative (ER-) cells are characterized by low RAR-alpha expression and by retinoid resistance.]. Sentence from MEDLINE/PubMed, a database of the U.S. National Library of Medicine."@en . . . . . "2017-02-19"^^ . . "Gene-disease associations inferred from text-mining the literature."@en . "DisGeNET evidence - LITERATURE"@en . "2017-10-17T13:12:30+02:00"^^ . . . . . . . . . . . "v5.0.0.0" . "v5.0.0" .