Figure 6. Schematic representation of the mechanistic role of TAMs in PDAC progression. In the tumor microenvironment, TAMs secrete TGF-β, which binds to the TGF-β receptors on the surface of PDAC cells and activates the TGF-β signaling pathway. This includes translocation of phosphorylated Smad2/3 (transcription factor) into the nucleus from the cytoplasm. The phospho-Smad2/3/4 complex upregulates Snail, a key transcriptional factor required for the expression of EMT-related genes. Subsequently, EMT promotes metastasis of PDAC cells.