DDR1 and neoplasm: Aligned with our observation of T cell exclusion in the tumor core of FR‒ tumors (Figs. 1k, 3h), we found an exclusive enrichment of DDR1, a collagen I receptor, within FR‒ tumors (Supplementary Fig. S6o, p), suggesting a potential interplay between tumor and stroma in FR‒ HCCs, particularly with CAF-FAP characterized by high expression of COL1A1 (Fig. 4b).