Figure 4. Quantitative real-time
polymerase chain reaction analyses of p21WAF1/CIP1 mRNA
expression in human corneal endothelial cells at various ages. Total
RNA was isolated from HCECs of each group, and the first-strand cDNA
were aynthesized from equal amounts of total RNA. Quantitative
real-time PCR was performed to analyze p21WAF1/CIP1
mRNA expression. A shows the expression of p21WAF1/CIP1
from the eight age groups normalized to GAPDH mRNA. B
demonstrates fold change in p21WAF1/CIP1 expression
relative to the calibrator of the 20-year-old group. C is the
comparison of the average level of p21WAF1/CIP1 mRNA
expressed in HCECs between the young (≤ 30 years) and old (≥ 50 years)
donors. Data are presented as mean±standard deviation and a p<0.05
is considered to be statistically significant. Results indicate no
significant increase (p=0.875) in p21WAF1/CIP1 mRNA
expression in HCECs from the old donors.