CLDN18

CLDN18
Identifiers
Aliases	CLDN18, SFTA5, SFTPJ, claudin 18
External IDs	OMIM: 609210; MGI: 1929209; HomoloGene: 9489; GeneCards: CLDN18; OMA:CLDN18 - orthologs
Gene location (Human)
Chr.	Chromosome 3 (human)
End	138,033,655 bp
Gene location (Mouse)
Chr.	Chromosome 9 (mouse)
End	99,599,320 bp
RNA expression pattern
	Top expressed in
	pylorus; ; lower lobe of lung; ; cardia; ; right lung; ; upper lobe of lung; ; upper lobe of left lung; ; body of stomach; ; gastric mucosa; ; visceral pleura; ; fundus;
	Top expressed in
	mucous cell of stomach; ; right lung lobe; ; epithelium of stomach; ; pyloric antrum; ; left lung; ; left lung lobe; ; blastocyst; ; duodenum; ; embryo; ; right kidney;
	More reference expression data
	; ; ; ;
	More reference expression data
Gene ontology
Molecular function	structural molecule activity; identical protein binding;
Cellular component	integral component of membrane; cell junction; plasma membrane; membrane; bicellular tight junction;
Biological process	negative regulation of protein localization to nucleus; TNFSF11-mediated signaling pathway; calcium-independent cell-cell adhesion via plasma membrane cell-adhesion molecules; digestive tract development; negative regulation of osteoclast development; negative regulation of bone resorption; response to ethanol;
	Sources:Amigo / QuickGO
Orthologs
	51208
	56492
	ENSG00000066405
	ENSMUSG00000032473
	P56856
	P56857
	NM_016369; NM_001002026
	NM_001194921; NM_001194922; NM_001194923; NM_019815
	NP_001002026; NP_057453
	NP_001181850; NP_001181851; NP_001181852; NP_062789
	Wikidata
View/Edit Human	View/Edit Mouse

Claudin-18 is a protein that in humans is encoded by the CLDN18 gene.⁵ It belongs to the group of claudins.

CLDN18 belongs to the large claudin family of proteins, which form tight junction strands in epithelial cells .⁶ [supplied by OMIM]⁵

Clinical significance

Isoform 2 (Claudin 18.2) is abundant in gastric tumors.⁷

Zolbetuximab targets Claudin 18.2 to help treat gastric and gastroesophageal junction cancers.⁸⁹ ¹⁰

References

GRCh38: Ensembl release 89: ENSG00000066405 – Ensembl, May 2017
GRCm38: Ensembl release 89: ENSMUSG00000032473 – Ensembl, May 2017
"Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
"Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
"Entrez Gene: CLDN18 claudin 18".
Niimi T, Nagashima K, Ward JM, et al. (2001). "claudin-18, a Novel Downstream Target Gene for the T/EBP/NKX2.1 Homeodomain Transcription Factor, Encodes Lung- and Stomach-Specific Isoforms through Alternative Splicing". Mol. Cell. Biol. 21 (21): 7380–90. doi:10.1128/MCB.21.21.7380-7390.2001. PMC 99911. PMID 11585919.
Antibody Shines in Advanced Gastric Cancer - IMAB362 leads to longer remission, better survival. June 2016
"Astellas' VYLOY™ (zolbetuximab) Approved in Japan for Treatment of Gastric Cancer a". www.prnewswire.com. 2024-03-26. Retrieved 2024-09-29.
Ouladan S, Orouji E (March 2025). "CAR-T Cells in Colorectal Cancer: Pioneering New Avenues in Solid Tumor Immunotherapy". Journal of Clinical Oncology. 42 (23): 2637–2639. doi:10.1200/JCO.24.02081. PMC 11895826. PMID 39805063.
Liu, Jian; Yang, Jing; Sun, Ying (July 2025). "CLDN18.2–targeting antibody–drug conjugate IBI343 in advanced gastric or gastroesophageal junction adenocarcinoma: a phase 1 trial". Nature Medicine. na (na): s41591-025-03783-8. doi:10.1038/s41591-025-03783-8. PMC 12443601. PMID 40670773.

External links

Human CLDN18 genome location and CLDN18 gene details page in the UCSC Genome Browser.

Further reading

Kniesel U, Wolburg H (2000). "Tight junctions of the blood–brain barrier". Cell. Mol. Neurobiol. 20 (1): 57–76. doi:10.1023/A:1006995910836. PMC 11537529. PMID 10690502. S2CID 26473781.
Heiskala M, Peterson PA, Yang Y (2001). "The roles of claudin superfamily proteins in paracellular transport". Traffic. 2 (2): 93–8. doi:10.1034/j.1600-0854.2001.020203.x. PMID 11247307. S2CID 12132159.
Tsukita S, Furuse M, Itoh M (2001). "Multifunctional strands in tight junctions". Nat. Rev. Mol. Cell Biol. 2 (4): 285–93. doi:10.1038/35067088. PMID 11283726. S2CID 36524601.
Tsukita S, Furuse M (2003). "Claudin-based barrier in simple and stratified cellular sheets". Curr. Opin. Cell Biol. 14 (5): 531–6. doi:10.1016/S0955-0674(02)00362-9. PMID 12231346.
González-Mariscal L, Betanzos A, Nava P, Jaramillo BE (2003). "Tight junction proteins". Prog. Biophys. Mol. Biol. 81 (1): 1–44. doi:10.1016/S0079-6107(02)00037-8. PMID 12475568.
Strausberg RL, Feingold EA, Grouse LH, et al. (2003). "Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences". Proc. Natl. Acad. Sci. U.S.A. 99 (26): 16899–903. Bibcode:2002PNAS...9916899M. doi:10.1073/pnas.242603899. PMC 139241. PMID 12477932.
Clark HF, Gurney AL, Abaya E, et al. (2003). "The Secreted Protein Discovery Initiative (SPDI), a Large-Scale Effort to Identify Novel Human Secreted and Transmembrane Proteins: A Bioinformatics Assessment". Genome Res. 13 (10): 2265–70. doi:10.1101/gr.1293003. PMC 403697. PMID 12975309.
Oh JH, Yang JO, Hahn Y, et al. (2006). "Transcriptome analysis of human gastric cancer". Mamm. Genome. 16 (12): 942–54. doi:10.1007/s00335-005-0075-2. PMID 16341674. S2CID 69278.
Matsuda Y, Semba S, Ueda J, et al. (2007). "Gastric and intestinal claudin expression at the invasive front of gastric carcinoma". Cancer Sci. 98 (7): 1014–9. doi:10.1111/j.1349-7006.2007.00490.x. PMC 11159341. PMID 17459057. S2CID 28029778.
Liu F, Koval M, Ranganathan S, Fanayan S, Hancock WS, Lundberg EK, Beavis RC, Lane L, Duek P, McQuade L, Kelleher NL, Baker MS (2015). "A systems proteomics view of the endogenous human claudin protein family". J Proteome Res. 15 (2): 339–359. doi:10.1021/acs.jproteome.5b00769. PMC 4777318. PMID 26680015.

[refGRCh38Ensembl-1] GRCh38: Ensembl release 89: ENSG00000066405 – Ensembl, May 2017

[refGRCm38Ensembl-2] GRCm38: Ensembl release 89: ENSMUSG00000032473 – Ensembl, May 2017

[3] "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.

[4] "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.

[entrez-5] "Entrez Gene: CLDN18 claudin 18".

[Niimi2001-6] Niimi T, Nagashima K, Ward JM, et al. (2001). "claudin-18, a Novel Downstream Target Gene for the T/EBP/NKX2.1 Homeodomain Transcription Factor, Encodes Lung- and Stomach-Specific Isoforms through Alternative Splicing". Mol. Cell. Biol. 21 (21): 7380–90. doi:10.1128/MCB.21.21.7380-7390.2001. PMC 99911. PMID 11585919.

[FAST-2016-7] Antibody Shines in Advanced Gastric Cancer - IMAB362 leads to longer remission, better survival. June 2016

[8] "Astellas' VYLOY™ (zolbetuximab) Approved in Japan for Treatment of Gastric Cancer a". www.prnewswire.com. 2024-03-26. Retrieved 2024-09-29.

[9] Ouladan S, Orouji E (March 2025). "CAR-T Cells in Colorectal Cancer: Pioneering New Avenues in Solid Tumor Immunotherapy". Journal of Clinical Oncology. 42 (23): 2637–2639. doi:10.1200/JCO.24.02081. PMC 11895826. PMID 39805063.

[10] Liu, Jian; Yang, Jing; Sun, Ying (July 2025). "CLDN18.2–targeting antibody–drug conjugate IBI343 in advanced gastric or gastroesophageal junction adenocarcinoma: a phase 1 trial". Nature Medicine. na (na): s41591-025-03783-8. doi:10.1038/s41591-025-03783-8. PMC 12443601. PMID 40670773.

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