Figure 1.

Expression levels of RNA-dependent protein kinase (PKR) in liver tumor tissues and adjacent normal tissues. Liver tumor tissue samples were collected from four hepatocellular carcinoma patients, and the (A) mRNA expression of PKR, as well as (B) protein expression of PKR and phosphorylation of PKR, were measured. (A) Relative fold changes of PKR mRNA expression levels, measured by reverse transcription quantitative polymerase chain reaction, in the liver tumor tissue and normal tissue samples. Error bars signify standard deviations (+/-) of three independent tests of tissue samples taken from the same patient. (B) PKR total protein and phosphorylation at Thr451 levels in tumor (T) and normal (N) tissue samples from patients 1–4 were measured with western blotting. β-actin served as an internal reference.