Figure 1. Detection of HPV E6/E7 in HNSCC cell lines. (A) RT-PCR was performed on total RNA harvested from HNSCC cell lines as described in Materials and Methods. Expected sizes of PCR fragments were detected using E6-specific primers (298 bp) and E7-specific primers (315 bp) in UPCI:SCC090, UM-SCC-47 and UD-SCC-2 cells. Expression of β-actin RNA was used as a control. (B) Three HPV-positive HNSCC cell lines were transfected with 100 nM nonspecific siRNA or siRNA directed against the E6/E7 bicistronic RNA. After 48 h, total RNA was prepared and E6/E7 RNA expression was assessed by RT-PCR. Similar results were obtained in three independent experiments.