Furthermore, in scRNA-seq profiling of CTLs from patients with advanced basal cell carcinoma (BCC)34, anti-PD-1 treatment induced an activated CD8+ T cell population that had lower ETS1 and higher IFNG expression than the exhausted population (Fig. 3k and Extended Data Fig. 5k), with similar effects observed in squamous cell carcinoma (SCC) (Extended Data Fig. 5l). Here, PDCD1 is linked to skin basal cell carcinoma.