Table 1

Accumulated data on RAR and RXR binding and transactivation of the used retinoids

RetinoidBinding (IC50, nm)aActivation (EC50, nm)b
9cRA (RAR/RXR)13c17c15c13c14c18c
tRA (RAR)7c5c6c6.7c2.8c3.5c
TTNPB (RAR)36d22d15d2.1c1.1c4.9c
RAR-subtype-selective agonist
AM80 (RAR-α)62e280e816e1.46e6.87e148.66e
AM580 (RAR-α)8e131e450e0.36e24.56e27.86e
CD417 (RAR-β)6500f36f426f71.1f3.56f69.1f
CD437 (RAR-γ)6500f2480f77f140f28.4f7.3f
RAR-subtype-selective antagonist
Ro 41-5253 (RAR-α)60d2400d3300d>1000d?g?g
RXR-reactive agonist
9cRA (RAR/RXR)70h?g?g1.5h?g?g
Ro 25-7386 (RXR-α)110i?g150i1.4i?g>10000i
  • a Retinoid concentration required to inhibit 50% of the binding of radioactively labeled RA.

  • b Retinoid concentration at which 50% of receptors are transcriptionally activated as determined in reporter assays applying RAR/RXR-subtype expression vectors and reporter genes under the control of response element-containing promoters.

  • c Le Motte et al. (16).

  • d Keidel et al. (17).

  • e K. Shudo, personal communication.

  • f B. Shroot, personal communication.

  • g unknown.

  • h Apfel et al. (18).

  • i M. Klaus, personal communication.