Tumor-infiltrating CD103+CD8+hnRNPA2B1+ tissue-resident T cells indicate poor prognosis in patients with clear cell renal cell carcinoma

Tumor heterogeneity and the complex immune microenvironment make it challenging to identify candidates for immunotherapy using dominant biomarkers. Tumor-infiltrating CD8+T cells, particularly CD103+CD8+ tissue-resident T cells and their specific subsets, are generally linked to better outcomes in many cancers, but their role in renal cancer remains largely unexplored. Here, we report that tumor-infiltrating CD103+CD8+hnRNPA2B1+ tissue-resident T cells can serve as an unfavorable prognostic factor for ccRCC patients and may be related to PD-1 treatment outcomes. We assessed the infiltration of CD103+CD8+T, CD103+CD8+hnRNPA2B1+T and other CD8+T cell subsets in ccRCC using multiplex immunofluorescence staining, and evaluated their links to patient clinicopathological features and prognosis. With published single-cell data from ccRCC patients treated with PD-1 therapy, we studied the expression differences of hnRNPA2B1 in tumor-infiltrating CD8+ T cells between responders and nonresponders. Compared with adjacent normal tissues, the infiltration levels of CD103+CD8+T, CD103+CD8+hnRNPA2B1+T cells, and CD103+CD8+Bhlhe40+T cells in ccRCC tissues were all significantly higher (all P values were <0.01). Moreover, patients with a higher degree of infiltration of these cells had worse overall survival (HR = 0.3490, 95% CI: 0.09338 to 1.304, P = 0.0144). All of them can serve as independent prognostic factors for ccRCC patients (HR = 3.753, 95% CI: 1.317 to 10.693, P = 0.013). Single-cell transcriptomics revealed that tumor-infiltrating CD8+T cells in patients responding to PD-1 antibody treatment had higher hnRNPA2B1 expression compared with nonresponders. In summary, our study indicates that tumor-infiltrating CD103+CD8+hnRNPA2B1+ tissue-resident T cells can serve as predictive factors and indicators for unfavorable prognosis and patient responses to PD-1 treatment outcomes in ccRCC patients.