TGIF1是一种重要的转录调控因子，其表达失常与肿瘤的发生和转移有关。本研究从分子水平、细胞水平、整体动物和人群研究四个层面探讨TGIF1与乳腺癌发生转移之间的关系及其分子生物学机制。首先，以两种高度转移的乳腺癌细胞(4T1和MDA-MB-231)为模型构建TGIF1低表达细胞株和以低转移的人乳腺癌细胞(MCF-7)为模型构建TGIF1过表细胞株，观察细胞体外迁移及侵袭能力变化；其次，动物体内实验观察TGIF1过表达/低表达的乳腺癌细胞在体内发生转移的差异；进一步，在人群乳腺癌组织标本中观察TGIF1和Twist表达及TGIF1与不同肿瘤病理类型、肿瘤分期和肿瘤转移状态的关系；最后，本研究在分子水平深入探讨TGIF1对Twist表达调控的分子机制。

TGIF1 is an important transcription factor, which is involved in occurance and metastasis of various types of cancer. In this study, we will focus on to explore the association between TGIF1 and breast cancer metastasis and its related molecular mechanism on the base of four aspects such as moleculer level, cellular level, animal model and population study. First, we will observe the difference in migration and invasion between TGIF1 overexpressed/silenced breast cancer cells and their controls correspondingly. Secondly, we will observe the difference in metastasis between TGIF1 overexpressed/silenced breast cancer cells and their controls correspondingly in vivo. Thirdly, we will observe the correlation of Twist expression with TGIF1 expression in human breast cancer samples and the correlation of TGIF1 expression with different histological type, stage and metastatic status. At last, we will explore the molecular mechanism of the effects of TGIF1 on Twist expression.