Figure 1.

CAPaSC express integrin α_vβ₃. ProAgio induces CAPaSC apoptosis. (A) Levels of αV (IB, integrin αV) and β3 (IB, integrin β3) integrin in activated and inactivated human primary PaSC were analyzed by immunoblot. PaSC were activated by culturing for 48 hours in the presence of 5 ng/mL transforming growth factor (TGF)-β. Inactivated PaSC are the cells that are in day 1 culture without TGF-β. (B) (Left) Representative (tissue samples from 9 patients and a tissue array of 60 patients) images and (right) quantification of integrin β₃-positive cells in stromal and adenocarcinoma (cancer cells) areas of the IHC staining of integrin β₃ of PDAC patient tumor tissue samples (n = 69). (C and D) Overall survival (C) and relapse-free survival (D) of PDAC patients in the groups of high and low expression of integrin αv (ITGAV, top), integrin β₃ (ITGB3, middle), and α-SMA (ACTA2, bottom) were plotted from the KM-plotter data base. ITGAV, ITGB3, and ACTA2 expression high (red line) denotes that the mRNA levels of the gene in the tumor of the patients are higher than the median value of mRNA of the gene in the entire patient group, and expression low (black line) is defined by the mRNA levels of the gene in the tumor of the patients are lower than the median value of the mRNA of the gene in the entire patient group. The number at the bottom of each panel indicates patient number. The hazard ratio (HR) and log-rank P value are indicated in each panel. (E) Apoptosis in activated PaSC (act. PaSC, red bar) or inactivated (PaSC, grey bar) PaSC after treatment with the indicated concentrations of ProAgio was measured by an apoptosis kit. Cell apoptosis is presented as the percentage of apoptosis by defining the apoptosis of untreated cells as 0%. (F) Co-immunoprecipitation of caspase 8 with integrin β₃ (IP, integrin β₃) in extracts of activated human primary PaSC that were treated with 5 μmol/L ProAgio for 6 hours were analyzed by immunoblots (IB, caspase 8). Immunoblot of integrin β₃ (IB, integrin β₃) indicates the amount of β₃ precipitated down in the co-IP. Immunoblot of ProAgio (IB, ProAgio) indicates co-precipitation of ProAgio with integrin β₃. (G) Mean tumor volume of subcutaneous xenograft of Panc1 with (gray line, Panc1 + CAPaSC) or without (black line, Panc1) co-implantation of PaSC. (B, E, and G) Error bars represent means ± SEM. GAPDH, glyceraldehyde-3-phosphate dehydrogenase. ∗P < .05; ∗∗P < .01; ∗∗∗P < .001; ∗∗∗∗P < .0001. co-IP, co-immunoprecipitation; IB, immunoblot; IP, immunoprecipitation; n.s., denotes not significant.