TACSTD2

TACSTD2
Identifiers
Aliases	TACSTD2, EGP-1, EGP1, GA733-1, GA7331, GP50, M1S1, TROP2, tumor-associated calcium signal transducer 2, tumor associated calcium signal transducer 2
External IDs	OMIM: 137290; MGI: 1861606; GeneCards: TACSTD2
Available structures
PDB	Ortholog search: PDBe RCSB
List of PDB id codes
	2MAE, 2MVK, 2MVL
Gene location (Human)
Chr.	Chromosome 1 (human)
End	58,577,252 bp
Gene location (Mouse)
Chr.	Chromosome 6 (mouse)
End	67,512,780 bp
RNA expression pattern
	Top expressed in
	palpebral conjunctiva; ; mucosa of pharynx; ; nasal epithelium; ; bronchial epithelial cell; ; amniotic fluid; ; oral cavity; ; gingival epithelium; ; skin of thigh; ; human penis; ; epithelium of nasopharynx;
	Top expressed in
	corneal stroma; ; lip; ; esophagus; ; skin of back; ; urothelium; ; skin of external ear; ; transitional epithelium of urinary bladder; ; cervix; ; granulocyte; ; skin of abdomen;
	More reference expression data
	; ;
	More reference expression data
Gene ontology
Molecular function	protein binding; signaling receptor activity; cadherin binding involved in cell-cell adhesion;
Cellular component	integral component of membrane; cytosol; lateral plasma membrane; membrane; plasma membrane; integral component of plasma membrane; basal plasma membrane; extracellular exosome; nucleus; extracellular space; bicellular tight junction;
Biological process	ureteric bud morphogenesis; response to stimulus; negative regulation of ruffle assembly; negative regulation of cell motility; cell surface receptor signaling pathway; negative regulation of branching involved in ureteric bud morphogenesis; cell population proliferation; regulation of epithelial cell proliferation; negative regulation of stress fiber assembly; negative regulation of substrate adhesion-dependent cell spreading; negative regulation of epithelial cell migration; visual perception; cell-cell adhesion; positive regulation of stem cell differentiation;
	Sources:Amigo / QuickGO
Orthologs
Databases	NCBI: entry; OMA: entry
	4070
	56753
	ENSG00000184292
	ENSMUSG00000051397
	P09758
	Q8BGV3
	NM_002353
	NM_020047
	NP_002344
	NP_064431
	Wikidata
View/Edit Human	View/Edit Mouse

Tumor-associated calcium signal transducer 2 (Trop-2) is a protein that is encoded by the TACSTD2 gene. The protein was identified via the monoclonal antibody GA733 (giving the name GA733-1). It was separately characterized as an epithelial cell-surface antigen (EGP-1) that was later recognized as a calcium signal transducer (TACSTD2/Trop-2).

This intronless gene is located at the short arm of chromosome 1 (1p32.1). It encodes a carcinoma-associated antigen that is closely related to epithelial cell adhesion molecule (EpCAM/TACSTD1). It transduces an intracellular calcium signal and acts as a cell surface receptor.

It is expressed in low levels in normal epithelia but is overexpressed in the membranes of many epithelial-derived cancers, including breast (especially triple-negative breast cancer), lung, gastric, colorectal, pancreatic, and ovarian, cancers. High expression of TACSTD2 in cancer drives proliferation and is associated with worse outcomes. Mutations of this gene result in gelatinous drop-like corneal dystrophy, an autosomal recessive disorder characterized by severe corneal amyloidosis leading to blindness.

Tissue distribution

Trop-2 expression was originally described in trophoblasts (placenta) and fetal tissues (e.g., lung). Later, its expression was described in the normal stratified squamous epithelium of the skin, uterine cervix, esophagus, and tonsillar crypts.

Function

Trop-2 plays a role in tumor progression by interacting with molecular signaling pathways traditionally associated with cancer development and progression. Aberrant overexpression of Trop-2 has been described in several solid cancers, such as colorectal, renal, lung, and breast cancers. Trop-2 expression has been described in some rare and aggressive malignancies, e.g., salivary duct, anaplastic thyroid, uterine/ovarian, and neuroendocrine prostate cancers. This overexpression is caused by deregulation at a transcriptional and posttranscriptional level.

Clinical significance

Cancer

Trop-2 causes cancer cell growth, proliferation, invasion, migration, and survival of cancer cells. Trop-2 is associated with tumor aggressiveness and poor prognosis. Tumor cell proliferation is disturbed when Trop-2 is knocked down. Trop-2 is a possible prognostic biomarker to identify high-risk patients, as well as an attractive therapeutic target for late-stage disease.

Therapeutics

This antigen is the target of antibody-drug conjugates including sacituzumab govitecan, datopotamab deruxtecan (Dato-DXd), and sacituzumab tirumotecan. In May 2026, Merck announced that its Phase 3 sacituzumab tirumotecan TroFuse-005 trial met both primary endpoints (overall survival + progression-free survival) in patients with advanced or recurrent endometrial cancer who had progressed after platinum chemotherapy and immunotherapy. it has Breakthrough Therapy Designation for EGFR-mutated NSCLC.

References

1 2 3 GRCh38: Ensembl release 89: ENSG00000184292 – Ensembl, May 2017
1 2 3 GRCm38: Ensembl release 89: ENSMUSG00000051397 – 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.
1 2 Goldenberg DM, Stein R, Sharkey RM (June 2018). "The emergence of trophoblast cell-surface antigen 2 (TROP-2) as a novel cancer target". Oncotarget. 9 (48): 28989–29006. doi:10.18632/oncotarget.25615. PMC 6034748. PMID 29989029.
↑ Linnenbach AJ, Seng BA, Wu S, Robbins S, Scollon M, Pyrc JJ, et al. (March 1993). "Retroposition in a family of carcinoma-associated antigen genes". Molecular and Cellular Biology. 13 (3): 1507–1515. doi:10.1128/MCB.13.3.1507. PMC 359462. PMID 8382772.
↑ Calabrese G, Crescenzi C, Morizio E, Palka G, Guerra E, Alberti S (April 2001). "Assignment of TACSTD1 (alias TROP1, M4S1) to human chromosome 2p21 and refinement of mapping of TACSTD2 (alias TROP2, M1S1) to human chromosome 1p32 by in situ hybridization". Cytogenetics and Cell Genetics. 92 (1–2): 164–165. doi:10.1159/000056891. PMID 11306819. S2CID 9708614.
1 2 "Entrez Gene: TACSTD2 tumor-associated calcium signal transducer 2".
1 2 3 Wen Y, Ouyang D, Zou Q, Chen Q, Luo N, He H, et al. (December 2022). "A literature review of the promising future of TROP2: a potential drug therapy target". Annals of Translational Medicine. 10 (24): 1403. doi:10.21037/atm-22-5976. PMC 9843409. PMID 36660684.
1 2 Vranic S, Gatalica Z (February 2022). "Trop-2 protein as a therapeutic target: A focused review on Trop-2-based antibody-drug conjugates and their predictive biomarkers". Bosnian Journal of Basic Medical Sciences. 22 (1): 14–21. doi:10.17305/bjbms.2021.6100. PMC 8860310. PMID 34181512.
↑ Datopotamab deruxtecan showed clinically meaningful overall survival improvement vs. chemotherapy in patients with advanced nonsquamous non-small cell lung cancer in TROPION-Lung01 Phase III trial
↑ "Merck Announces TroFuse-005 Trial Evaluating Sacituzumab Tirumotecan (Sac-TMT) Met Primary Endpoints of Overall Survival (OS) and Progression-Free Survival (PFS) in Certain Patients With Advanced or Recurrent Endometrial Cancer". Merck.com. 2026-05-18. Retrieved 2026-05-22.

Linnenbach AJ, Wojcierowski J, Wu SA, Pyrc JJ, Ross AH, Dietzschold B, et al. (January 1989). "Sequence investigation of the major gastrointestinal tumor-associated antigen gene family, GA733". Proceedings of the National Academy of Sciences of the United States of America. 86 (1): 27–31. Bibcode:1989PNAS...86...27L. doi:10.1073/pnas.86.1.27. PMC 286396. PMID 2911574.
Fornaro M, Dell'Arciprete R, Stella M, Bucci C, Nutini M, Capri MG, et al. (September 1995). "Cloning of the gene encoding Trop-2, a cell-surface glycoprotein expressed by human carcinomas". International Journal of Cancer. 62 (5): 610–618. doi:10.1002/ijc.2910620520. PMID 7665234. S2CID 23260113.
El Sewedy T, Fornaro M, Alberti S (January 1998). "Cloning of the murine TROP2 gene: conservation of a PIP2-binding sequence in the cytoplasmic domain of TROP-2". International Journal of Cancer. 75 (2): 324–330. doi:10.1002/(SICI)1097-0215(19980119)75:2<324::AID-IJC24>3.0.CO;2-B. PMID 9462726.
Ripani E, Sacchetti A, Corda D, Alberti S (May 1998). "Human Trop-2 is a tumor-associated calcium signal transducer". International Journal of Cancer. 76 (5): 671–676. doi:10.1002/(SICI)1097-0215(19980529)76:5<671::AID-IJC10>3.0.CO;2-7. PMID 9610724.
Tsujikawa M, Kurahashi H, Tanaka T, Nishida K, Shimomura Y, Tano Y, et al. (April 1999). "Identification of the gene responsible for gelatinous drop-like corneal dystrophy". Nature Genetics. 21 (4): 420–423. doi:10.1038/7759. PMID 10192395. S2CID 2275476.
Nakamura T, Nishida K, Dota A, Adachi W, Yamamoto S, Maeda N, et al. (May 2000). "Gelatino-lattice corneal dystrophy: clinical features and mutational analysis". American Journal of Ophthalmology. 129 (5): 665–666. doi:10.1016/S0002-9394(00)00369-X. PMID 10844062.
Kinoshita S, Nishida K, Dota A, Inatomi T, Koizumi N, Elliott A, et al. (July 2000). "Epithelial barrier function and ultrastructure of gelatinous drop-like corneal dystrophy". Cornea. 19 (4): 551–555. doi:10.1097/00003226-200007000-00029. PMID 10928776. S2CID 43011710.
Tsujikawa M, Tsujikawa K, Maeda N, Watanabe H, Inoue Y, Mashima Y, et al. (August 2000). "Rapid detection of M1S1 mutations by the protein truncation test". Investigative Ophthalmology & Visual Science. 41 (9): 2466–2468. PMID 10937555.
Ha NT, Fujiki K, Hotta Y, Nakayasu K, Kanai A (July 2000). "Q118X mutation of M1S1 gene caused gelatinous drop-like corneal dystrophy: the P501T of BIGH3 gene found in a family with gelatinous drop-like corneal dystrophy". American Journal of Ophthalmology. 130 (1): 119–120. doi:10.1016/S0002-9394(00)00596-1. PMID 11004271.
Tasa G, Kals J, Muru K, Juronen E, Piirsoo A, Veromann S, et al. (November 2001). "A novel mutation in the M1S1 gene responsible for gelatinous droplike corneal dystrophy". Investigative Ophthalmology & Visual Science. 42 (12): 2762–2764. PMID 11687514.
Yoshida S, Kumano Y, Yoshida A, Numa S, Yabe N, Hisatomi T, et al. (June 2002). "Two brothers with gelatinous drop-like dystrophy at different stages of the disease: role of mutational analysis". American Journal of Ophthalmology. 133 (6): 830–832. doi:10.1016/S0002-9394(02)01407-1. PMID 12036680.
Ren Z, Lin PY, Klintworth GK, Iwata F, Munier FL, Schorderet DF, et al. (June 2002). "Allelic and locus heterogeneity in autosomal recessive gelatinous drop-like corneal dystrophy". Human Genetics. 110 (6): 568–577. doi:10.1007/s00439-002-0729-z. PMID 12107443. S2CID 24052349.
Ha NT, Chau HM, Cung LE, Thanh TK, Fujiki K, Murakami A, et al. (March 2003). "A novel mutation of M1S1 gene found in a Vietnamese patient with gelatinous droplike corneal dystrophy". American Journal of Ophthalmology. 135 (3): 390–393. doi:10.1016/S0002-9394(02)01952-9. PMID 12614764.
Gires O, Eskofier S, Lang S, Zeidler R, Münz M (2003). "Cloning and characterisation of a 1.1 kb fragment of the carcinoma-associated epithelial cell adhesion molecule promoter". Anticancer Research. 23 (4): 3255–3261. PMID 12926061.
Tian X, Fujiki K, Li Q, Murakami A, Xie P, Kanai A, et al. (March 2004). "Compound heterozygous mutations of M1S1 gene in gelatinous droplike corneal dystrophy". American Journal of Ophthalmology. 137 (3): 567–569. doi:10.1016/j.ajo.2003.08.008. PMID 15013888.
Murakami A, Kimura S, Fujiki K, Fujimaki T, Kanai A (2004). "Mutations in the membrane component, chromosome 1, surface marker 1 (M1S1) gene in gelatinous drop-like corneal dystrophy". Japanese Journal of Ophthalmology. 48 (4): 317–320. doi:10.1007/s10384-003-0064-5. PMID 15295654. S2CID 28358081.

This article on a gene on human chromosome 1 is a stub. You can help Wikipedia by adding missing information.

[refGRCh38Ensembl-1] 1 2 3 GRCh38: Ensembl release 89: ENSG00000184292 – Ensembl, May 2017

[refGRCm38Ensembl-2] 1 2 3 GRCm38: Ensembl release 89: ENSMUSG00000051397 – 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.

[Goldenberg_2018-5] 1 2 Goldenberg DM, Stein R, Sharkey RM (June 2018). "The emergence of trophoblast cell-surface antigen 2 (TROP-2) as a novel cancer target". Oncotarget. 9 (48): 28989–29006. doi:10.18632/oncotarget.25615. PMC 6034748. PMID 29989029.

[Linnenbach_1993-6] Linnenbach AJ, Seng BA, Wu S, Robbins S, Scollon M, Pyrc JJ, et al. (March 1993). "Retroposition in a family of carcinoma-associated antigen genes". Molecular and Cellular Biology. 13 (3): 1507–1515. doi:10.1128/MCB.13.3.1507. PMC 359462. PMID 8382772.

[Calabrese_2001-7] Calabrese G, Crescenzi C, Morizio E, Palka G, Guerra E, Alberti S (April 2001). "Assignment of TACSTD1 (alias TROP1, M4S1) to human chromosome 2p21 and refinement of mapping of TACSTD2 (alias TROP2, M1S1) to human chromosome 1p32 by in situ hybridization". Cytogenetics and Cell Genetics. 92 (1–2): 164–165. doi:10.1159/000056891. PMID 11306819. S2CID 9708614.

[entrez-8] 1 2 "Entrez Gene: TACSTD2 tumor-associated calcium signal transducer 2".

[Wen_2022-9] 1 2 3 Wen Y, Ouyang D, Zou Q, Chen Q, Luo N, He H, et al. (December 2022). "A literature review of the promising future of TROP2: a potential drug therapy target". Annals of Translational Medicine. 10 (24): 1403. doi:10.21037/atm-22-5976. PMC 9843409. PMID 36660684.

[Vranic_2022-10] 1 2 Vranic S, Gatalica Z (February 2022). "Trop-2 protein as a therapeutic target: A focused review on Trop-2-based antibody-drug conjugates and their predictive biomarkers". Bosnian Journal of Basic Medical Sciences. 22 (1): 14–21. doi:10.17305/bjbms.2021.6100. PMC 8860310. PMID 34181512.

[11] Datopotamab deruxtecan showed clinically meaningful overall survival improvement vs. chemotherapy in patients with advanced nonsquamous non-small cell lung cancer in TROPION-Lung01 Phase III trial

[12] "Merck Announces TroFuse-005 Trial Evaluating Sacituzumab Tirumotecan (Sac-TMT) Met Primary Endpoints of Overall Survival (OS) and Progression-Free Survival (PFS) in Certain Patients With Advanced or Recurrent Endometrial Cancer". Merck.com. 2026-05-18. Retrieved 2026-05-22.