kidney adrenal intestine 11 3 weeks foetal brain 10 6 weeks and foetal eye 16 5 weeks data not shown ish analysis of colorectal liver metastasis biopsies showed that expression of ecsm4 was restricted to vascular endothelial cells of the tumour vessels only fig1 and 18 no expression was detected in the surrounding normal tissue furthermore the enhanced expression in the vicinity of the necrotic tissues fig1 necrotic tissue is indicated by the bright signal labelled is indicative and consistent with induction of ecsm4 expression by hypoxia as such ecsm4 may be a novel hypoxia regulated gene the highly restricted expression pattern of ecsm4 in angiogenic vessels in normal and tumour tissues in adult is entirely consistent with the endothelial cell selective pattern of expression determined by the in silico analysis described in example 1 blocks of formalin fixed paraffin embedded tissues and tumours were obtained from the archives of the imperial cancer research fund breast pathology group at guys hospital london uk an antisense riboprobe to ecsm4 cdna was prepared for specific localisation of the ecsm4 mrna by in situ hybridisation the methods for pretreatment hybridisation washing and dipping of slides in ilford k 5 for autoradiography has been described previously poulsom r longcroft j m jeffrey r e rogers l and steel j h 1998 eur j histochem 42 121 132 films were exposed for 7 to 15 days before developing in kodak d19 and.