Figure 4

MiR-21 is essential for PA1 CSPCs self-renewal. Flow cytometric signal intensities were used to compare isotype-IgG-APC (left-hand side) and CD133-APC (right-hand side) in PA1 cells. Panel A shows the comparison of CD133+ populations in vector-infected cells (upper panel) and in anti-miR21-infected PA1 cells (lower panel). Sphere formation assay images of the PA1 cell colonies (black arrows indicate the tumor sphere). The sphere colony images were taken under a phase contrast fluorescence microscope (40×). The image on the left-hand side indicates vector-infected cells and the image on the right-hand side indicates anti-miR21-infected PA1 cell sphere colonies (B). Signal intensities of isotype-IgG-APC in PA1 cells (left-hand side) were compared with those of CD133-APC in PA1 cells (right-hand side). CD133+ populations in vector-infected PA1 cells (upper panel) were compared with those in pre-miR21-infected PA1 cells (lower panel) (C). Sphere formation assay images of the PA1 cell colonies (black arrows indicate the tumor sphere). The sphere colony images were taken using a phase contrast fluorescence microscope (40×). The image on the left-hand side indicates vector-infected cell sphere colonies and the image on the right-hand side indicates pre-miR21-infected PA1 cell sphere colonies (D). The scale bar represents 200 μm. APC, allophycocyanin; CSPCs, cancer stem/progenitor cells; IgG, immunoglobulin G; miR, microRNA.