Protein / target
Steroid 17-alpha-hydroxylase/17,20 lyase
Protein at a glance
Biological role
Steroid 17-alpha-monooxygenase
Strongest disease association
Congenital adrenal hyperplasia due to 17-alpha-hydroxylase deficiency
Therapeutic position
Established drug target
Derived from structured UniProt, Open Targets and literature data on this page.
Protein profile
Canonical identity and biological annotation from UniProt.
Function overview
A cytochrome P450 monooxygenase involved in corticoid and androgen biosynthesis.
View complete UniProt function annotationHide complete annotation
A cytochrome P450 monooxygenase involved in corticoid and androgen biosynthesis (PubMed:22266943, PubMed:25301938, PubMed:27339894, PubMed:9452426). Catalyzes 17-alpha hydroxylation of C21 steroids, which is common for both pathways. A second oxidative step, required only for androgen synthesis, involves an acyl-carbon cleavage. The 17-alpha hydroxy intermediates, as part of adrenal glucocorticoids biosynthesis pathway, are precursors of cortisol (Probable) (PubMed:25301938, PubMed:9452426). Hydroxylates steroid hormones, pregnenolone and progesterone to form 17-alpha hydroxy metabolites, followed by the cleavage of the C17-C20 bond to form C19 steroids, dehydroepiandrosterone (DHEA) and androstenedione (PubMed:22266943, PubMed:25301938, PubMed:27339894, PubMed:36640554, PubMed:9452426). Has 16-alpha hydroxylase activity. Catalyzes 16-alpha hydroxylation of 17-alpha hydroxy pregnenolone, followed by the cleavage of the C17-C20 bond to form 16-alpha-hydroxy DHEA (PubMed:36640554). Also 16-alpha hydroxylates androgens, relevant for estriol synthesis (PubMed:25301938, PubMed:27339894). Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate, and reducing the second into a water molecule, with two electrons provided by NADPH via cytochrome P450 reductase (CPR; NADPH-ferrihemoprotein reductase) (PubMed:22266943, PubMed:25301938, PubMed:27339894, PubMed:9452426)
Subcellular location
Domains and Gene Ontology detail (17)Hide
Gene Ontology
- Caxon
- Cendoplasmic reticulum
- Cendoplasmic reticulum membrane
- Cneuronal cell body
- Fheme binding
- Firon ion binding
- Flyase activity
- Foxygen binding
- Fsteroid 17-alpha-monooxygenase activity
- Pandrogen biosynthetic process
- Pcortisol biosynthetic process
- Pglucocorticoid biosynthetic process
Biological roles
What this protein does, drawn together from its UniProt function, Gene Ontology terms and Reactome pathways.
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Metabolic enzyme activity
- ·progesterone metabolic process
- ·steroid metabolic process
View underlying pathways (3)Hide underlying pathways
Concepts derived from UniProt GO Reactome — each badge above shows which sources supported that role.
Interaction neighbourhood
Proteins with the strongest functional or physical association. Node size and line weight reflect STRING confidence; hover or select a partner to inspect one association.
Functional and physical associations from STRING v12.0. Only associations with this protein are drawn — partner-to-partner links are not part of this evidence.
Approved medicines with mapped indications
Approved therapies targeting this protein, grouped by what they are approved to treat — the disease-first view of the medicines below. Relationships come from the canonical approved-indication graph (ChEMBL phase-4), the same source as the drug cards.
Approved indications from ChEMBL (phase-4), via the canonical drug→disease graph.
Drugs targeting this protein
How approved and investigational drugs engage this protein — mechanism and action type, direct vs complex targeting, and how broadly each acts across other targets. A drug-first view (the section above groups the approved ones disease-first); direct binders with few recorded targets are listed first.
Cytochrome P450 17A1 inhibitor
Indicated for Prostatic Neoplasms
ChEMBL mechanism, action type, target identity and approved indications. Open Targets clinical status.
Translational evidence
Why this target matters therapeutically, strongest evidence first. Disease associations are gene-level (via the gene that encodes this protein) and open into the full confidence synthesis; the development universe, tractability and safety annotations are target-level, from Open Targets.
Strongest disease associations · via encoding gene CYP17A1
Gene-level evidence surfaced through the gene CYP17A1that encodes this protein — not a direct protein–disease relationship. Ranked by Forefront's causal-directness weighting, so genetically- and clinically-evidenced diseases lead over ones that merely share the literature.
View evidence synthesis (5)Hide
The evidence agreement range shows how closely the independent evidence families agree — it is not a statistical confidence interval, and nothing here is fitted to outcome data. Derived from Open Targets evidence types under Forefront weighting; the per-type scores above show the calculation.
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Drug development
6 compounds recorded · 3 approved · 3 in clinical development
View all recorded compounds (6)Hide
Open Targets known-drugs universe. Drug name and highest clinical stage only — the disease relationship is NOT read from this slice (it carries trial-context noise); approved indications come from the canonical graph above.
Tractability
Small molecules — Strong
Protein degraders — Emerging
View underlying tractability evidence (5)Hide
Raw Open Targets tractability assessment buckets, by modality.
Clinical trials
Trials of drugs that target this protein — reached indirectly through those drugs, so a trial listed here studies the drug, not the protein. Ranked by active status, then clinical phase and recency, and spread across the targeting drugs.
View all trials (26)Hide
ClinicalTrials.gov via the drug-target graph.
What's happening now
Recent therapeutic activity around this target — regulatory actions, clinical trials and safety signals for 3 drugs that target this protein, plus publications where such a drug is a genuine subject. Every item is reached indirectly through the drug, not the protein itself; incidental mentions (a paper that merely measures a drug) and press items are excluded.
- Label change
Label change: ABIRATERONE ACETATE (ANDA208371)
- New publicationNiraparib and abiraterone acetate plus prednisone for HRR-deficient metastatic castration-sensitive prostate cancer: a randomized phase 3 trial.
- New publicationAR alterations inform circulating tumor DNA detection in metastatic castration resistant prostate cancer patients.
- New publicationLuteinizing hormone-releasing hormone receptor agonists and antagonists in prostate cancer: effects on long-term survival and combined therapy with next-generation hormonal agents.
- New publicationCirculating Tumor DNA Assessment for Treatment Monitoring Adds Value to PSA in Metastatic Castration-Resistant Prostate Cancer.
- New publicationRucaparib or Physician's Choice in Metastatic Prostate Cancer.
- Regulatory approval
Approval: Abiraterone Mylan (EMA)
- Regulatory approval
Approval: Abiraterone Krka (EMA)
- Regulatory approval
Approval: Abiraterone Accord (EMA)
- Regulatory approval
Approval: ABIRATERONE ACETATE (ANDA208371)
- Accelerated approval granted
Accelerated approval: Ketoconazole Esteve (previously Ketoconazole HRA) (EMA)
- Accelerated approval granted
Accelerated approval: Zytiga (EMA)
Objective event titles are shown unmodified; the event kind and significance line are derived from structured fields. Forefront AttentionEvent stream aggregating Europe PMC Regulatory filings ClinicalTrials.gov.