Fig. 1

RNA recovery from filter-trapped K1 cells fixed for liquid-based cytology. RNA was extracted from the fixed K1 cells after incubation with Proteinase K-containing for the indicated periods at 55 °C. RNA recovery from K1 cells fixed with CytoRich-Red (a) and CytoRich-Blue (b). Black bars and gray bars represent the RNA yield from 20,000 to 100,000 cells, respectively. Quality of RNAs extracted from K1 cells fixed with CytoRich-Red (c) and CytoRich-Blue (d). The analysis using Agilent 2100 bioanalyzer revealed that 28S and 18S ribosomal RNAs (correspond to the bands at approximately 1900 nt and 3900 nt on the charts, respectively) remained nearly intact, leading to high RINs. N/A not assessed