|
| | ER | ER | ERα/ERβ heterodimer | AR |
|
| Proliferation | Stimulates (in the presence of E2 and coactivators) | Suppresses but may depend on variant
(only ER1 binds E2 with high affinity) | Data support suppression but may depend on ER variant and density of each receptor subtype | Stimulates or suppresses (may depend on concurrent signaling pathways activated) |
|
| Apoptosis | Suppresses (in the presence of E2 and coactivators) | Promotes (but may depend on variant) | Data support promotion but may depend on ER variant and density of each receptor subtype | Stimulates or suppresses (may depend on concurrent signaling pathways or variant) |
|
| PR
gene | Activates | Represses activation | Represses activation | — |
|
| Prognostic factor | Yes | Uncertain but possible | Uncertain but possible | Uncertain but possible |
|
| ERE binding | Yes | Only ER1, βins, and ER2 bind ERE | Yes | Androgen response element (ARE) |
|
| Dimerization with ER and ER1 | Yes | Yes for wild type and ins; ER2 binds ER only | — | No |
|
| Receptor variants | Best characterized is hER-alpha36 | At least 5
(ER1 (wild type), delta5, 18 a.a insert (ins), ERcx (ER2), and 5) | — | At least 7 splice variants have been identified (AR-V1, AR-V2, AR-V3, AR-V4, AR-V5, AR-V6, and AR-V7) but many more likely to exist |
|
| AF-2 | Independent | Dependent | — | — |
|
| Interaction with other signaling pathways | Yes | Yes | Yes | Yes |
|
