Figure 4

MiR203 opposes the activities of normal and cancer stem cells. (a) RT-qPCR analysis of total RNA for mature miR-203 expression levels isolated from parental (ML) and secondary mammospheres (2°-MS) of MCF-7 cells (mammospheres enrich for stem cells). Data are means±S.D.; n=3, asterisk indicates P<0.05. (b) Mammosphere formation assay of IMEC cells transiently transfected with miR-control of mature miR203 (60 nM); 25 000 cells were then transferred to low binding plates and grown for 14 days. Mammospheres were trypsinized and total cells were counted per experimental group (left), Representative 10 × phase contrast images of mammospheres from each experimental group (right). Data are means±S.E.; n=3, P-values are indicated. (c) Flow cytometric analysis of IMECs labeled with the stem cell enrichment markers CD24 and CD44. IMECs were transiently transfected with miR-control or mature miR203 (60 nM). Seventy-two hours after transfection, cells were labeled with CD24-PE and CD44-FITC and analyzed via flow cytometry. Representative flow cytometry density plots of CD24 versus CD44 from experiment conduced in triplicate