CDK4 as a Radioligand Therapy Target
CDK4, cyclin dependent kinase 4, is a cell-surface protein. In Human Protein Atlas immunohistochemistry, CDK4 staining is highest in head and neck cancer (100% of samples positive), cervical cancer (83% of samples positive) and thyroid cancer (100% of samples positive). Clinical status: Clinical-stage (up to phase 3, any modality).
Is CDK4 a good radioligand therapy target?
Scored against the six criteria that decide whether a protein can become a radioligand therapy:
- ✅ Cell-surface accessibility: Localized to the cell surface, so a radioligand can reach it from circulation.
- ✅ Tumor expression: High IHC staining in head and neck cancer, 100% of samples positive.
- ❔ Internalization: Not yet assessed.
- ✅ Clinical precedent: Clinical-stage (up to phase 3, any modality)
- ❔ Shedding: Not yet assessed.
- ❔ Normal-tissue dosimetry: Check kidney, liver, bone marrow and salivary expression in the Human Protein Atlas tissue atlas.
CDK4 expression in cancer
Protein expression of CDK4 across 20 cancer types from Human Protein Atlas immunohistochemistry. The score is a weighted staining intensity from 0 to 1; "% positive" is the share of patient samples with detectable staining.
| Cancer type | IHC score | Level | % positive |
|---|---|---|---|
| Head and Neck Cancer | 0.75 | High | 100% |
| Cervical Cancer | 0.69 | High | 83% |
| Thyroid Cancer | 0.67 | High | 100% |
| Ovarian Cancer | 0.64 | High | 92% |
| Melanoma | 0.61 | High | 100% |
| Skin Cancer | 0.53 | High | 83% |
| Bladder Cancer | 0.53 | High | 75% |
| Breast Cancer | 0.52 | High | 73% |
| Lung Cancer | 0.50 | Medium | 83% |
| Testicular Cancer | 0.44 | Medium | 83% |
| Lymphoma | 0.42 | Medium | 67% |
| Colorectal Cancer | 0.39 | Medium | 67% |
| Prostate Cancer | 0.36 | Medium | 73% |
| Glioma | 0.36 | Medium | 73% |
| Kidney Cancer | 0.27 | Medium | 64% |
| Neuroendocrine Tumors | 0.25 | Medium | 50% |
| Pancreatic Cancer | 0.24 | Medium | 55% |
| Liver Cancer | 0.21 | Medium | 36% |
| Gastric Cancer | 0.19 | Low | 33% |
| Endometrial Cancer | 0.14 | Low | 42% |
Is CDK4 internalized?
Nuclens has not yet extracted internalization evidence for CDK4. Internalization matters for radioligands because an internalizing receptor traps the radionuclide inside the tumor cell. Run a full analysis to pull the latest literature.
CDK4 clinical trials
Clinical-stage (up to phase 3, any modality). Nuclens hasn't indexed trials for CDK4 yet. Search ClinicalTrials.gov for CDK4 trials.
CDK4 normal tissue expression
Normal-tissue expression in dose-limiting organs (kidney, liver, bone marrow, salivary glands) drives radioligand dosimetry risk. Nuclens is re-validating its normal-tissue values, so they are not shown here yet. See CDK4 in the Human Protein Atlas tissue atlas, and read how normal-tissue expression predicts radioligand dosimetry risk.
CDK4 gene essentiality (DepMap)
CRISPR knockout effect across 1258 cancer cell lines: -0.74 (essential, below −0.5). Radioligands kill by radiation, not by blocking the target, so essentiality matters less than for inhibitors. A non-essential target can still be an excellent radioligand target.
Related head and neck cancer radioligand targets
EGFR · c-MET (MET) · HER3 (ERBB3) · ITGAV · SSTR2 · B7-H3 (CD276) · STEAP2 · Mesothelin (MSLN)
See all radioligand therapy targets in head and neck cancer.
See how CDK4 ranks against 15,000 targets for your indication.
Run a free analysisData sources
Subcellular localization: UniProt via Open Targets (CC BY 4.0 / CC0). Tumor immunohistochemistry: Human Protein Atlas (CC BY-SA 4.0). Clinical trials: ClinicalTrials.gov (public domain). Gene essentiality: DepMap (CC BY 4.0). Internalization and shedding: AI-extracted from PubMed abstracts, so verify against the cited papers before relying on them. Nuclens is a first-pass triage layer, not a substitute for wet-lab validation or clinical dosimetry. Derived expression data on this page is shared under CC BY-SA 4.0.