biostudies-literatureSiqueira JMSalivary Gland Tumor BiorepositoryRyan Smith Adenoid Cystic Carcinoma FundAdenoid Cystic Carcinoma Research FoundationNIDCR NIH HHSWold FoundationU.S. Department of DefenseNCI NIH HHSDeWayne Everage Adenoid Cystic Carcinoma FundResearch Histology Core Laboratory658-666https://www.ebi.ac.uk/biostudies/studies/S-EPMC12419983biostudies-literatureUnknown54(8)<h4>Background</h4>Adenoid cystic carcinoma (ACC) is a common salivary gland carcinoma with high recurrence and distant metastasis rates. Currently, there is no standard systemic treatment available. TROP2 is a transmembrane glycoprotein involved in the oncogenesis of several tumors that can be therapeutically targeted by a TROP2-antibody-drug conjugate (ADC). We aimed to characterize TROP2 expression in ACC and assess TROP2 as a potential therapeutic target.<h4>Methods</h4>TROP2 immunohistochemistry was performed in a tissue microarray including 165 ACC of salivary gland. The tumors were grouped according to the histological pattern as non-solid, solid + non-solid, or solid. TROP2 protein expression in ACC cell lines was assessed and subjected to drug screening with TROP2-ADC.<h4>Results</h4>TROP2 expression was high in 59%, moderate in 30%, weak in 8%, and negative in 3% of cases. TROP2 expression was significantly higher in non-solid compared with solid or solid + non-solid (p < 0.001). Notably, TROP2 expression was heterogenous among the dual cellular component, with TROP2 expression identified predominantly in the ductal and not in the myoepithelial cells. In vitro drug screening demonstrated that TROP2-ADC had selective anti-tumor effect in TROP2 expressing ACC cells.<h4>Conclusions</h4>TROP2 expression is prevalent in ACC, particularly in the ductal cell component of the non-solid tumors. The pre-clinical drug screening findings provide a biological rationale for exploring TROP2 as a therapeutic target in TROP2-expressing ACC.<h4>Trial registration</h4>clinicaltrials.gov: NCT05884320; NCI-2023-04260.Journal of oral pathology & medicine : official publication of the International Association of Oral Pathologists and the American Academy of Oral PathologyTROP2 Expression in Salivary Gland Adenoid Cystic Carcinoma (ACC) According to Histologic Subtype: Therapeutic Implications.PMC12419983W81XWH-21-0409P30 CA016672NCI CA16672HHSN268200900039CHHSN268200900039C 04El-Naggar AKNunes FDMcGrail DJMatos LLde Sousa LGSpiotto MTHanna EYSiqueira JMHoff COMitani MFerrarotto RCarvalho GLMitani YMarques-Piubelli MLBonini FLin SYfalseTROP2 Expression in Salivary Gland Adenoid Cystic Carcinoma (ACC) According to Histologic Subtype: Therapeutic Implications.<h4>Background</h4>Adenoid cystic carcinoma (ACC) is a common salivary gland carcinoma with high recurrence and distant metastasis rates. Currently, there is no standard systemic treatment available. TROP2 is a transmembrane glycoprotein involved in the oncogenesis of several tumors that can be therapeutically targeted by a TROP2-antibody-drug conjugate (ADC). We aimed to characterize TROP2 expression in ACC and assess TROP2 as a potential therapeutic target.<h4>Methods</h4>TROP2 immunohistochemistry was performed in a tissue microarray including 165 ACC of salivary gland. The tumors were grouped according to the histological pattern as non-solid, solid + non-solid, or solid. TROP2 protein expression in ACC cell lines was assessed and subjected to drug screening with TROP2-ADC.<h4>Results</h4>TROP2 expression was high in 59%, moderate in 30%, weak in 8%, and negative in 3% of cases. TROP2 expression was significantly higher in non-solid compared with solid or solid + non-solid (p < 0.001). Notably, TROP2 expression was heterogenous among the dual cellular component, with TROP2 expression identified predominantly in the ductal and not in the myoepithelial cells. In vitro drug screening demonstrated that TROP2-ADC had selective anti-tumor effect in TROP2 expressing ACC cells.<h4>Conclusions</h4>TROP2 expression is prevalent in ACC, particularly in the ductal cell component of the non-solid tumors. The pre-clinical drug screening findings provide a biological rationale for exploring TROP2 as a therapeutic target in TROP2-expressing ACC.<h4>Trial registration</h4>clinicaltrials.gov: NCT05884320; NCI-2023-04260.2025-01-01T00:00:00Z2025 Sep2026-06-01T13:57:13.227Z2026-04-08T13:16:01.283ZS-EPMC124199834062499010.1111/jop.70008