PT - JOURNAL ARTICLE AU - WAZIR, UMAR AU - LI, AMBER X. AU - WANG, CAROLYN CAI AU - GAO, HENSON HAN AU - MARTIN, TRACEY A. AU - JIANG, WEN G. AU - MOKBEL, KEFAH TI - CD84 as a Prognostic Biomarker and Therapeutic Target in Breast Cancer: Interconnections With PDL1, CD74, and Immune Tolerance Mechanisms AID - 10.21873/cgp.20521 DP - 2025 Jul 01 TA - Cancer Genomics - Proteomics PG - 557--563 VI - 22 IP - 4 4099 - http://cgp.iiarjournals.org/content/22/4/557.short 4100 - http://cgp.iiarjournals.org/content/22/4/557.full SO - Cancer Genomics Proteomics2025 Jul 01; 22 AB - Background/Aim: Cluster of differentiation 84 (CD84), a member of the signalling lymphocytic activating molecule (SLAM) family, has emerged as a potential prognostic biomarker and therapeutic target in breast cancer. This study explored CD84 expression and its correlation with clinicopathological features in a well-characterised cohort.Materials and Methods: Using quantitative real-time PCR, mRNA expression levels of CD84 and related molecules, including PDL1, CD74, and other immune tolerance markers, were analysed.Results: The findings reveal that elevated CD84 expression predicts poor overall survival, independent of conventional prognostic factors such as the Nottingham Prognostic Index (NPI). Notably, a combined signature of CD84, CD48, VAV1, and CTNNB1 demonstrated stronger prognostic power than individual markers. CD84 exhibited significant correlations with immunosuppressive molecules, including PDL1 and CD74, underscoring its role in fostering immune tolerance within the tumour microenvironment.Conclusion: CD84 may mediate an immunosuppressive phenotype, facilitating immune evasion in breast cancer. This highlights its potential as a therapeutic target, particularly in triple-negative breast cancer, to overcome immune resistance and enhance treatment efficacy.