microRNA-21 expression in the PDAC stroma is associated with poor prognosis.

(A) Representative images of histoscores for miR-21 in situ hybridization in PDAC tumor cells and stroma. These two cellular compartments were scored as 0 negative (not depicted), 1 weakly positive, 2 moderately positive, 3 strongly positive. (B) Kaplan-Meier analysis reveals that high miR-21 stromal expression is associated with decreased overall survival (P = 0.04). miR-21 expression intensity was dichotomized into high (n = 73) vs. low (n = 72) based on the median score of all tumors.