Immune checkpoint inhibitors (ICIs) have become a crucial component in the treatment of bladder cancer (BLCA). ICIs enhance the ability of T cells to attack tumors by blocking immune inhibitory pathways such as PD-1, PD-L1, or CTLA-4. However, the response to ICIs varies significantly among BLCA patients, with only a small percentage of patients benefit from these agents. Screening for potential beneficiaries is an essential path for the development of precision medicine. Encouragingly, some molecular markers, such as chemokines, may serve as predictors of effective immune response in BLCA [
1‐
5]. In addition, the development of interventions targeting chemokines may help enhance the effectiveness of immune therapy for BLCA.
As a secreted chemokine, C-X-C motif Chemokine Ligand 10 (CXCL10) is primarily produced by fibroblasts, cancer cells, endothelial cells, and monocytes in response to IFN-γ secretion [
6]. Through binding to its unique receptor, CXC chemokine receptor 3 (CXCR3), CXCL10 exhibits pleiotropic functions in tumor biology [
7]. Specifically, the CXCL10-CXCR3 axis can regulate immune cell activation, differentiation and migration to promote anti-tumor immunity through paracrine signaling. Conversely, tumor-derived CXCL10 can interact with CXCR3 to induce tumor cell proliferation, angiogenesis, and other pro-tumorigenic effects [
6,
8‐
10]. CXCL10 has been demonstrated to coordinate anti-tumor immunity in BLCA. In the study by Tian et al., an immune signature containing CXCL10 demonstrated significant correlation with the immune microenvironment of BLCA, offering a new perspective for immunotherapy of BLCA [
11]. In the healthy bladders of mice, Seow et al. found that the use of Bacillus Calmette-Guerin (BCG) alone significantly upregulated CXCL10 [
12]. Conversely, in human bladder tissues, Muthuswamy et al. found that the use of BCG alone did not result in upregulation of CXCL10. However, the combination of BCG with IFNα and poly-I was found to be effective in enhancing CXCL10 in BLCA tissues and promoting cytotoxic T lymphocytes (CTLs) infiltration [
13]. Ibrahim and colleagues conducted more in-depth research and made similar findings: the use of PGE2 antagonists alone, and the combination with BCG and indomethacin, can selectively enhance the chemoattractant factor CXCL10 for CTLs, achieving immune reprogramming in BLCA [
14]. Additionally, research from Japanese scholars indicates that neutrophils expressing MHC class II and CXCL10 internally suggest a state of BCG-induced anti-tumor activity in BLCA [
15]. Although the above studies suggest the potential of CXCL10 as a biomarker for immunotherapy in BLCA, overall, there is still a lack of research exploring the relationship between CXCL10 and recent immunotherapies, such as ICIs, in BLCA.
In the present research, we utilized multiple public databases to explore the expression patterns, prognostic value, and genomic instability of CXCL10 in BLCA. Moreover, we conducted an investigation into the role of CXCL10 in the BLCA immune microenvironment and its impact on immunotherapy. Our study provides new insights into the potential application of immunotherapy for BLCA.