Real-time RT-PCR analysis of anti-E7 RNA. CaSki cells were infected with R3616, R3617, R5225, and R5226 at an m.o.i. of 0.1, 1.0, and 3.2, and harvested at 16 h.p.i. Total RNA was extracted and reverse transcription performed. Real-time PCR using the cDNA samples was performed as described in Materials and Methods. The diagram shows the amount of anti-E7 RNA, corrected for the 18S rRNA levels in these samples. Both R5225 and R5226 express antisense RNA in a dose-dependent manner. The statistical significances of the differences in anti-E7 copy numbers in comparison with uninfected CaSki cells are indicated by asterisks above the columns (***: p < 0.001; ****: p < 0.0001).