Abstract
Analysis of thyroid tumorigenesis in xenograft mouse model is important to study human thyroid cancer. Recent studies have made big strides toward understanding the molecular mechanisms by which thyroid hormone nuclear receptors (TR) act to maintain normal cellular functions in growth, differentiation, and development. Despite growing interest, the role of TR in oncogenesis remains to be fully elucidated. Two TR genes give rise to three major TR isoforms: TRα1, TRβ1, and TRβ2. These TR subtypes express in a tissue- and development-dependent manner. Research has been directed at understanding the mechanisms by which TR could mediate aberrant cellular signaling that contributes to oncogenesis, at dissecting possible distinct roles of TR isoforms in oncogenesis, and at the differential susceptibility of target tissues to the oncogenic actions of TR. This chapter gives a brief overview of the current undersatanding of known molecular oncogenic actions of TR. Here, we describe analysis of thyroid tumorigenesis used in interrogating the in vivo oncogenic actions of TR.