Expression of hepatocyte nuclear factor-1 alpha mRNA in human anaplastic thyroid cancer cell lines and tumors

Background: Hepatocyte nuclear factor (HNF)-1 alpha and HNF-1 beta are related transcription factors that are mainly expressed in liver cells. Our previous study showed that HNF-1 beta was highly expressed in papillary thyroid cancer cell lines and tumors. HNF-1 alpha mRNA, however, was not detected in differentiated thyroid cancer cell lines. The objective of this study was to determine whether HNF-1 alpha is expressed in dedifferentiated anaplastic thyroid cancer cells. Methods: Total RNA isolated from six anaplastic thyroid cancer cell lines and 38 surgical samples was analyzed for HNF-1 alpha mRNA by conventional reverse-transcription polymerase chain reaction (RT-PCR) or real-time RTPCR. HNF-1 alpha DNA binding activity was measured by gel retardation assay and HNF-1 alpha protein was identified by Western blotting. Results: HNF-1 alpha mRNA was expressed in four of the six anaplastic cell lines. The presence of HNF-1 alpha protein and DNA binding activity was detected in three lines with higher HNF-1 alpha mRNA level. Three cell lines also expressed HNF-1b. HNF-1 alpha transcripts were also detected in five out of six anaplastic tumors, but not in the papillary tumors except one with weak PCR signal. Conclusion: HNF-1 alpha mRNA was detected in high frequency in anaplastic thyroid cancer cell lines and tumors. HNF-1 alpha might play a role in the pathogenesis of anaplastic thyroid cancer.