Objective      To determine the expression profiles and distribution of T cell factor-3 (TCF-3) in non-small cell lung cancer (NSCLC).      Methods      TCF-3 expression was examined in 50 NSCLC tissue specimens and their corresponding normal lung specimens by immunohistochemical assay (S-P method). The mRNA levels of TCF-3 were detected in 5 cell lines of NSCLC (A549

H460

H226

H520 and SK-MES-1 cell lines ) and 2 human normal bronchial epithelial cell lines (HBE and BEP-2D cell lines) by real-time fluorescence quantitative PCR. The protein level of TCF-3 gene in the cell lines was detected by Western blotting.      Results      Among the 50 lung cancer specimens

24 samples showed high expression of TCF-3 (48%)

and 22 samples had the expression both in the cytoplasm and nuclei. But no TCF-3 expression was detected in 50 corresponding normal lung specimens. The expression of TCF-3 was found at mRNA and protein levels in the cell lines A549

H520

HBE

and BEP-2D.      Conclusion      TCF-3 is expressed in the NSCLC tissue as well as cell lines. TCF-3 protein is located in the nuclei and cytoplasm

but mainly in the former.