Expression of Smo in pancreatic cancer CD44+CD24+cells and construction of a lentiviral expression vector to silence Smo.

The present study focused on the roles of members of the Hedgehog (Hh) signaling pathway in the maintenance of malignant biological characteristics, such as tumorigenesis, similar to that of pancreatic tumor cells. Cluster of differentiation (CD)44+CD24+/CD44-CD24- cells were isolated from three different pancreatic cancer cell lines by flow cytometry. Among the three pancreatic cancer cell lines, the SW1990 cell line exhibited the highest percentage of CD44+CD24+ cells, which accounted for 39.9% of the total. The expression of members of the Hh signaling pathway in CD44+CD24+/CD44-CD24- cells was detected using reverse transcription-polymerase chain reaction and western blot analysis. The results demonstrated that members of the Hh signaling pathway were differentially expressed in CD44+CD24+ cells compared with CD44-CD24-, normal pancreatic duct cells and unsorted SW1990 cells. In addition, lentiviral expression vectors expressing Smoothened (Smo) small interfering RNA (siRNA) were constructed. Following transfection with the lentiviral expression vectors, Smo expression was markedly reduced in CD44+CD24+ cells. The present study represents a preliminary investigation into the biological characteristics of CD44+CD24+ pancreatic cancer cells.