» Articles » PMID: 40059728

Prognostic Value of Trop-2 Expression in Nonmetastatic Triple-Negative Breast Cancer and Correlation With Emerging Biomarkers

Overview
Journal Cancer Med
Specialty Oncology
Date 2025 Mar 10
PMID 40059728
Authors
Affiliations
Soon will be listed here.
Abstract

Introduction: Triple-Negative Breast Cancer (TNBC) is an aggressive breast cancer subtype, in which targeting the Trophoblast cell-surface antigen-2 (Trop-2), using antibody-drug conjugates (ADC), results in significant clinical improvement. However, clinicopathological correlations with Trop-2 protein expression levels remain limited in TNBC patients.

Methods: Here we assessed by immunohistochemistry (IHC) using the mouse monoclonal anti-Trop-2 antibody (Enzo, Cat. ENZ-ABS380) cell membrane Trop-2 expression levels and classified them in 3 H-Score classes, low (< 100), moderate (100-200), and strong (> 200). We also evaluated potential associations with clinicopathological variables including basal-like and molecular apocrine phenotypes, immune infiltrate characteristics, PTEN and PIK3CA alterations in a large retrospective series of 228 nonmetastatic TNBC patients.

Results: Trop-2 expression was evaluated as low, moderate and strong in 12.3%, 28.9%, and 58.8% of the cases respectively. Only 3 tumors showed no Trop-2 expression. Interestingly, Trop-2 expression was not associated with classical breast cancer clinicopathological variables, HER2 levels or molecular subtype, neither did we observe an association with relapse-free survival. Only a marginal association with pT1 tumors was observed, which tended to express increased levels of Trop-2 protein. In order to determine possible fluctuations of Trop-2 protein expression levels during the course of the disease, we studied a second independent cohort of 18 TNBC comprised of serial tissue samples (diagnostic biopsies, surgical resection specimens and corresponding patients-derived xenografts (PDX)). Trop-2 levels remained globally stable between cognate tumor samples with only one exception corresponding to a Trop-2-negative tumor giving rise to a Trop-2-positive PDX.

Conclusions: As Trop-2 expression appears nearly constant and independent of classical TNBC variables and outcome, association of anti-Trop-2 therapies with other targeted therapies can be evaluated without reducing the population in specific TNBC subgroups.

References
1.
Elias A . Triple-negative breast cancer: a short review. Am J Clin Oncol. 2009; 33(6):637-45. DOI: 10.1097/COC.0b013e3181b8afcf. View

2.
Zhao W, Kuai X, Zhou X, Jia L, Wang J, Yang X . Trop2 is a potential biomarker for the promotion of EMT in human breast cancer. Oncol Rep. 2018; 40(2):759-766. DOI: 10.3892/or.2018.6496. View

3.
Vidula N, Yau C, Rugo H . Trophoblast Cell Surface Antigen 2 gene (TACSTD2) expression in primary breast cancer. Breast Cancer Res Treat. 2022; 194(3):569-575. DOI: 10.1007/s10549-022-06660-x. View

4.
Guiu S, Mollevi C, Charon-Barra C, Boissiere F, Crapez E, Chartron E . Prognostic value of androgen receptor and FOXA1 co-expression in non-metastatic triple negative breast cancer and correlation with other biomarkers. Br J Cancer. 2018; 119(1):76-79. PMC: 6035246. DOI: 10.1038/s41416-018-0142-6. View

5.
Du Manoir S, Orsetti B, Bras-Goncalves R, Nguyen T, Lasorsa L, Boissiere F . Breast tumor PDXs are genetically plastic and correspond to a subset of aggressive cancers prone to relapse. Mol Oncol. 2014; 8(2):431-43. PMC: 5528550. DOI: 10.1016/j.molonc.2013.11.010. View