Breeding of the transgenic MMTV-PyMT mice with the transgenic mouse strain B6.129P2-Axltm1Dgen/J in order to study the role of Axl in mammary tumor development and metastasis

Axl is a member of the TAM (Tyro-Axl-Mer) receptor tyrosine kinases (RTK) transmembrane receptor tyrosine kinase. TAM family regulates whole range of cellular responses. Axl, particularly, is expressed in embryonic tissues and plays a role in the neural and mesenchymal development. In adult tissues its expression is restricted to smooth muscle cells. Relative to normal expression, increased level of Axl is specific for various disease states. In patients suffering from cancer Axl expression is associated with metastatic lesions and with poor overall patient survival. The B6.129P2-Axltm1Dgen/J mouse strain allow us to obtain a functional knockdown of Axl. The transgenic MMTV-PyMT mice develop mammary tumors with metastasis in the lung, by crossing this strain in an axl knockdown we will be able to see the effect of the absence of axl in tumor development and metastasis.This new animal model will allow us to compare the tumor signalisation in the presence or absence of Axl.