These stromal cells include tumour fibroblasts, which express growth factors such as TGFβ2 that act on the adjacent tumour cells (van Zijl et al, 2009), as well as proteins of the extracellular matrix, which are modified by matrix metalloproteinases derived from tumour cells to regulate tumour invasion and angiogenesis (Kalluri, 2003). Here, TGFB2 is linked to neoplasm.