Description_x000D_ Biochem/physiol Actions_x000D_ MM11253 (SR11253) is a high-affinity RARγ-selective retinoid acid (RA) receptor antagonist (IC50 = 44 nM against ATRA for binding RARγ; IC50 =1 μM in case of RARα, RARβ, RXRα) that prevents >90% growth inhibitory effect of retinoids AHPN/CD437 (1 μM in CA-OV3 & SK-SKOV3 cultures) and M11389 (1 μM in SCC-25 squamous cell carcinoma cultures) when used at equal concentration. MM11253 also effectively blocks the inhibitory effect of R667 (RARγ agonist) against IL-1β-induced MMP production from rabbit corneal fibroblasts (80% vs. 11% inhibition by 0,1 nM R667, respectively, without or with 0.03 nM MM11253).