AR
🔍 What is AR?
The AR gene encodes the androgen receptor, a nuclear hormone receptor that binds androgens (e.g., testosterone and dihydrotestosterone). AR acts as a transcription factor regulating genes involved in male sexual development and maintenance.
📊 Prevalence of AR Alterations in Cancer
| Cancer Type | AR Alterations Prevalence |
|---|---|
| Prostate cancer | Nearly all advanced prostate cancers show AR alterations (amplification, mutations, splice variants) |
| Breast cancer | ~10-15% (especially in some triple-negative subtypes) |
| Other cancers | Rare but occasionally seen in other hormone-sensitive tumors |
⚙️ Mechanism of Oncogenic Activation
- AR amplification and overexpression: Increase sensitivity to low androgen levels, driving prostate cancer progression.
- Point mutations in AR can alter ligand specificity or confer resistance to anti-androgen therapies.
- Splice variants lacking the ligand-binding domain can result in constitutive, ligand-independent activity.
- Activated AR promotes transcription of genes driving proliferation and survival in hormone-dependent tumors.