PDCD1 and colorectal carcinoma: Taken together, these findings suggest that, in MASLD, CAF-derived HA acts on CD44-expressing TAMs and CRC cells to regulate PD-L1 expression; PD-L1 expression on M2-TAMs is associated with the distance and the density of CAFs near M2-TAMs; and the increased PD-L1 binds to PD-1 expressed on CD8+ T cells to support an immunosuppressive TME in metastatic foci in the presence of steatosis (Figure 6L).