Mutational Spectrum of Gelsolin and Its Down Regulation Is Associated with Breast Cancer

Abstract

Cytoskeletal rearrangement occurs in variety of cellular processes and involves a wide spectrum of proteins. Gelsolin super family proteins control actin organization by severing and capping filament ends and nucleating actin assembly. Gelsolin is the founding member of this family and plays important role in pathogenesis of human neoplasia.This study aimed to investigate the germline mutations and expressional profile of Gelsolin in human breast cancer tissues. For germ line screening PCR-SSCP technique was used while expression was analyzed through quantitative real time PCR. Different types of mutations were observed in Gelsolin coding regions on exons 4, 10, 11, 14 and 15. These mutations include 3 missense nonsynonymous substitution mutations, 2 deletions, 1 insertion and 1 synonymous substitution mutation. Gelsolin transcript level was found significantly lower in breast tumor tissues compared to control samples (p=0.03). Low level of Gelsolin was found in metastatic patients (p=0.002) and patients who died from breast cancer (P=0.03) compared to disease free patients at final follow up. This study shows that level of Gelsolin is down regulated in breast cancer tissues and is linked with metastasis development and death in patients. It is concluded that genetic changes in coding regions of Gelsolin can potentially contribute to genetic instability. These genetic variations and expressional correlation with patient survival may prove to be of significant importance.