**4.8 NOTCH**

DELTA/JAGGED acting through the NOTCH pathway are implicated in both cell fate in the normal human mammary gland (Raouf et al., 2008) and regulation of cancer stem cells (CSCs) in both ductal carcinoma *in situ* and in invasive carcinoma of the breast (Dontu et al., 2004; Stylianou et al., 2006). This pathway is known to be transcriptionally induced by TGFβ/SMAD signalling and contributes to EMT (Zavadil et al., 2004). This pathway is cell type specific and can be either oncogenic through activation of the NKFB pathway or it can be tumour suppressive. Wang et al., (2006) provided evidence demonstrating that NOTCH receptor signalling regulates SNAIL 1 and 2, ZEB1 and vimentin.
