PTPN18
Protein Tyrosine Phosphatase Non-Receptor Type 18
Gene Information Card
| Symbol | PTPN18 |
|---|---|
| Full Name | Protein Tyrosine Phosphatase Non-Receptor Type 18 |
| Gene Type | Protein coding |
| Chromosomal Location | 2q21.1 |
| NCBI Gene ID | 26469 ncbi.nlm.nih.gov/gene/26469 |
| Ensembl ID | ENSG00000162909 |
| UniProt ID | Q99952 |
| OMIM ID | 606592 |
| HGNC ID | 9659 |
| Aliases | PTP-HSCF, BDP1 |
Description
PTPN18 encodes a member of the protein tyrosine phosphatase (PTP) family. The encoded protein is a non-receptor type tyrosine phosphatase that dephosphorylates phosphotyrosine residues, regulating cellular signaling pathways. It is known to interact with and dephosphorylate HER2 (ERBB2), thereby modulating HER2 signaling in breast cancer. PTPN18 is also involved in hematopoietic stem cell factor signaling.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Breast cancer | PTPN18 dephosphorylates HER2, reducing oncogenic signaling; loss of expression may promote tumor progression | PMID: 23382219; COSMIC |
| Gastric cancer | Altered PTPN18 expression linked to HER2 pathway dysregulation | PMID: 25605248 |
| Colorectal cancer | PTPN18 expression changes observed in tumor tissues | COSMIC |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Breast | 15.2 | Medium |
| Stomach | 10.8 | Medium |
| Colon | 8.5 | Low |
| Bone marrow | 6.3 | Low |
| Lung | 5.1 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| MCF7 (breast cancer) | 12.4 | HER2-positive line |
| MDA-MB-231 (breast cancer) | 9.7 | Triple-negative line |
| K562 (leukemia) | 7.8 | Myelogenous leukemia line |
| HeLa (cervical cancer) | 6.5 | Cervical adenocarcinoma line |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.101C>T (p.Thr34Met) | Missense | <0.1% | Unknown functional effect; reported in COSMIC |
| c.452A>G (p.Asn151Ser) | Missense | <0.1% | Located in phosphatase domain; potential impact on activity |
| c.784G>A (p.Gly262Arg) | Missense | <0.1% | Reported in breast cancer samples |
Mutation functional classification
Loss of Function (LOF)
Not well characterized; some missense variants may reduce phosphatase activity.
Gain of Function (GOF)
No confirmed gain-of-function mutations reported.
Dominant Negative (DN)
No evidence for dominant-negative effects.
View complete mutation data：ClinVar: https://www.clinvar.com/gene/26469 COSMIC: https://cancer.sanger.ac.uk/cosmic/gene/analysis?ln=PTPN18
Gene Ontology (GO)
| • protein tyrosine phosphatase activity | • dephosphorylation |
| • signal transduction | • negative regulation of ERBB2 signaling pathway |
| • cytoplasm |
Pathways
• HER2 signaling pathway
• ErbB signaling pathway
• Protein tyrosine phosphatase activity
Protein Summary
PTPN18 is a 382-amino acid non-receptor protein tyrosine phosphatase with a single catalytic domain. It localizes to the cytoplasm and regulates signaling by dephosphorylating substrates such as HER2. Its expression is moderate in breast and gastric tissues, and it is implicated in cancer through modulation of oncogenic tyrosine kinase signaling.
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| PTPN18 Knockout HEK293 Cell Line | EDJ-KQ1384 | Human | 26469 | Details Get a Quote |
| PTPN18 Knockout A-549 Cell Line | EDJ-KQ22187 | Human | 26469 | Details Get a Quote |
| PTPN18 Knockout HCT 116 Cell Line | EDJ-KQ22189 | Human | 26469 | Details Get a Quote |
| PTPN18 Knockout HeLa Cell Line | EDJ-KQ22190 | Human | 26469 | Details Get a Quote |
| Ptpn18 Knockout BV-2 Cell Line | EDC90284 | Mouse | 19253 | Details Get a Quote |
Displaying Records 1 To 5 Of 5 Records
