Role of the Tyrosine Kinase JAK2 in the Development and Progression of Breast Cancer

摘要

The ongoing proposal is aimed at examining the role of the Jak-Stat pathway and its contribution to breast cancer development and progression. To this end, the proposal has further examined the localization of Stat3 and Stat5a in oncogenic mouse models and human breast cancer samples. These data have demonstrated that the nuclear accumulation of Stat3 and Stat5a is a common feature of tumor samples from both mouse and human origin. Furthermore, experiments have established that expression of the water transporter aquaporin 5 (AQP5) is prevalent in oncogenic mouse models although its expression is independent of tumor grade. Finally, it has been demonstrated that the application of three defined protein markers has proved to be instrumental in the determination of stage- specific defects in mammary gland development. Although the generation of a Jak2 conditional knockout mouse model was unsuccessful, the data reported herein and in the literature strongly suggest a role for the Jak-Stat pathway in tumor development and/or progression.