SLC44A4 as a Radioligand Therapy Target
SLC44A4, solute carrier family 44 member 4, is a cell-surface protein. In Human Protein Atlas immunohistochemistry, SLC44A4 staining is highest in prostate cancer (100% of samples positive), colorectal cancer (75% of samples positive) and pancreatic cancer (70% of samples positive). Clinical status: Clinical-stage (up to phase 1, any modality).
Is SLC44A4 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 prostate cancer, 100% of samples positive.
- ❔ Internalization: Not yet assessed.
- ✅ Clinical precedent: Clinical-stage (up to phase 1, any modality)
- ❔ Shedding: Not yet assessed.
- ❔ Normal-tissue dosimetry: Check kidney, liver, bone marrow and salivary expression in the Human Protein Atlas tissue atlas.
SLC44A4 expression in cancer
Protein expression of SLC44A4 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 |
|---|---|---|---|
| Prostate Cancer | 0.64 | High | 100% |
| Colorectal Cancer | 0.44 | Medium | 75% |
| Pancreatic Cancer | 0.43 | Medium | 70% |
| Gastric Cancer | 0.39 | Medium | 83% |
| Endometrial Cancer | 0.30 | Medium | 55% |
| Breast Cancer | 0.27 | Medium | 60% |
| Bladder Cancer | 0.26 | Medium | 67% |
| Neuroendocrine Tumors | 0.25 | Medium | 75% |
| Cervical Cancer | 0.24 | Medium | 46% |
| Lung Cancer | 0.23 | Medium | 50% |
| Ovarian Cancer | 0.21 | Medium | 46% |
| Liver Cancer | 0.12 | Low | 18% |
| Head and Neck Cancer | 0.11 | Low | 33% |
| Kidney Cancer | 0.08 | Low | 17% |
| Skin Cancer | 0.06 | Low | 9% |
| Melanoma | 0.06 | Low | 17% |
Not detected by IHC in: lymphoma, thyroid cancer, testicular cancer, glioma.
Is SLC44A4 internalized?
Nuclens has not yet extracted internalization evidence for SLC44A4. Internalization matters for radioligands because an internalizing receptor traps the radionuclide inside the tumor cell. Run a full analysis to pull the latest literature.
SLC44A4 clinical trials
Clinical-stage (up to phase 1, any modality). Nuclens hasn't indexed trials for SLC44A4 yet. Search ClinicalTrials.gov for SLC44A4 trials.
SLC44A4 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 SLC44A4 in the Human Protein Atlas tissue atlas, and read how normal-tissue expression predicts radioligand dosimetry risk.
SLC44A4 gene essentiality (DepMap)
CRISPR knockout effect across 1253 cancer cell lines: -0.07 (not essential). 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 prostate cancer radioligand targets
PSMA (FOLH1) · HER3 (ERBB3) · c-MET (MET) · EGFR · EPCAM · FAP · B7-H3 (CD276) · STEAP2
See all radioligand therapy targets in prostate cancer.
See how SLC44A4 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.