Comprehensive multi-omics landscape exploration and functional characterization of TACSTD2 throughout pan-cancer

Tumor-associated calcium signal transducer 2 ( TACSTD2 ) is widely investigated in cancer research. Its overexpression across multiple cancers is linked to elevated tumor aggressiveness, metastasis, and poor prognosis, making it a potential biomarker for diagnosis, prognosis, and therapy. However, its role has not been explored at the multi-omics pan-cancer level. This study performed a comprehensive pan-cancer analysis to systematically investigate the expression profile, prognostic value, genetic alterations, functional pathways, immune infiltration, and therapeutic relevance of TACSTD2 across multiple cancer types. Besides, RT-qPCR was conducted to assess the expression of TACSTD2 in breast cancer cell lines. TACSTD2 showed widespread overexpression in different cancer types and was notably connected to poor prognosis, genomic instability, and pathways related to metastasis. Its expression levels were also closely correlated with immune infiltration and distinct immune subtypes. In triple-negative breast cancer (TNBC), spatial transcriptomic analysis confirmed that TACSTD2 was mainly expressed in malignant epithelial cells, and high TACSTD2 expression predicted unfavorable survival. Furthermore, RT-qPCR validation confirmed the upregulation of TACSTD2 in TNBC cell lines. Our findings indicate that TACSTD2 is closely associated with tumor progression and tumor microenvironment remodeling, supporting its potential as a biomarker. Importantly, TACSTD2 might represent potential biomarker and candidate target for TNBC.