Increased Farnesoid X Receptor Expression in Non-small Cell Lung Cancer.

Abstract

Objective: Farnesoid X activated receptor (FXR) is one of the nuclear hormone receptors which is activated by farnesol and related molecules, and is specifically expressed in tissues in which bile acids function. Although hepatocellular carcinoma cells (HepG2) are reported to express FXR, there is no study examining its expression in other types of cancer. In this study, we studied the expression of FXR mRNA and protein in non-small cell lung cancers (NSCLC). Methods: The expression of FXR messenger RNA (mRNA) and protein in NSCLC was examined by reverse transcription-polymerase chain reaction (RT-PCR), Western blot analysis, and immunohistochemistry. Results: FXR mRNA was expressed in 6 of 8 NSCLC tissues by RT-PCR. Western blot analysis exhibited the presence of FXR protein in 8 of 9 NSCLC tissues. Immunohistochemistry showed immunoreactive FXR in 35 of 37 NSCLC tissues. The intensity and frequency of FXR expression was strongest in adenocarcinoma followed by squamous cell carcinoma and large cell carcinoma, respectively. Conclusion: Our results suggest that FXR may play a role in the pathogenesis of NSCLC.