Downregulation of CRNN in ESCC.

<p>(A) qRT-PCR was used to compare CRNN mRNA levels between tumor and corresponding non-tumor tissues in 56 ESCC cases. **, <i>P</i><0.01. (B) Absent expression of CRNN could be observed in all tested ESCC cell lines in both mRNA level (upper panel) and protein level (lower panel) detected by RT-PCR and western blot analysis, respectively. GAPDH was used as a loading control. N1, pool total RNA or protein from 5 non-tumor esophageal tissue specimens. (C) Representatives of immunostaining with anit-CRNN antibody in ESCC cases. Positive staining (brown) was detected in non-tumor esophageal epithelial cells but not in tumor cells. The slide was counterstained with hematoxylin. Original magnification, 200×magnification. (D) Kaplan-Meier analysis shows that downregulation of CRNN was significantly associated with poorer overall survival in 249 ESCC cases (<i>P</i><0.001, Log-rank test).