(C) A validation cohort of PDAC patients (n=21) that underwent direct resection was stained for CSF-1 (scale bar represents 100 µm), PSR (scale bar represents 500 µm) and α-SMA (scale bar represents 200 µm). OK8 is low in CSF-1 expression and high in PSR and α-SMA expression, while the opposite accounts for OK7. (D) Correlation of % of PSR in the tumor and CSF-1 expressing tumor cells, as indicated in panel C. R2 and P-value were analyzed with linear regression. n=21 primary PDAC samples (E) Correlation of % of α-SMA in the tumor and CSF-1 expressing tumor cells, as indicated in panel C, R2 and P-value were analyzed with linear regression. n=21 primary PDAC samples 