Low levels of WWOX protein immunoexpression correlate with tumour grade and a less favourable outcome in patients with urinary bladder tumours

Aims: To correlate the immunohistochemical detection of WWOX with histological measures and disease progression within the whole spectrum of urothelial bladder neoplasms. Methods and results: One hundred and one patients with primary bladder tumours were retrospectively analysed. Immunohistochemically, a polyclonal antibody was utilized and the level of WWOX protein expression was analysed by using a combined score system based on intensity of the reaction and percentage of immunoreactive tumour cells. WWOX protein expression was consistently expressed in non‐neoplastic urothelium, whereas a progressive loss of immunoreactivity was observed as tumour grade and stage increased (P