Expression of the WASP Verprolin-Homologues (WAVE Members) in Human Breast Cancer

Background: The WASP family proteins have been indicated to play a vital role in the formation of membrane protrusions required for cell locomotion. WAVE proteins are an important subfamily that also plays a crucial role in actin polymerisation, which is vital to cell migration. However, not much is known about the clinical significance of this subfamily in cancers. We report, for the first time, the expression of the WAVE molecules, at protein and mRNA levels, in human breast cancer. Materials and Methods: The expression of the 3 WAVE molecules at the mRNA and protein levels in a cohort of 122 human breast cancers and 32 normal breast tissues were analysed and correlated with the patients’ pathological and clinical information as well as outcome (120 months follow-up). Results: All 3 WAVE molecules were detected in mammary tissues. WAVE2 transcripts were expressed in high levels in all breast tumours. Over-expression of WAVE2 was seen in node-positive cases as well as in moderately and poorly differentiated tumours. Also, high levels of WAVE2 expression were associated with death due to disease (p = 0.02) at follow-up. No distinct associations were found between the WAVE1 and WAVE3 transcripts and the breast cancer cells.