Fig. 6.

Overexpression of pericyte marker NG2 in large-scale duct lesion formation. A: tissue map of pancreatic section with PanINs. Yellow box indicates the zoom-in area. The PanIN domain and area in transition to PanIN are enlarged for examination. Numbers 1-5 denote examples of PanIN-1. Green, NG2; red, vascular; white, nuclear and tissue autofluorescence. B: projection of NG2 overexpression in large-scale duct lesion formation. The view focuses on the zoom-in area in A. NG2 overexpression is notably observed in both the PanIN domain and the area in transition. C: quantitation of NG2 overexpression in duct lesion formation. Early stage duct lesion refers to the condition in Fig. 2, A–C. The NG2 signals associated with “Lesion” refer to the signals acquired from the perilesional region. A comparable size of the area was assigned to the normal acinar domain to derive the NG2 signals in the normal area. Line indicates average of data points (***P < 0.001). Note that because pancreatic stellate cells exist in the lesion microenvironment, we did not rule out that activated stellate cells could become NG2-positive and contribute to the increase in perilesional NG2 density. D–F: NG2-positive pericytes and perilesional myofibroblast-like cells in large-scale duct lesion formation. Numbers denote the same duct lesions shown in A and B. Cyan box in D is enlarged in F. White arrows in E and F: NG2-positive perivascular pericytes. Yellow arrows in D and F: perilesional NG2-positive myofibroblast-like cells.