Fine Needle Aspiration Cytology: A Tool to Study NHERF1 Expression as a Potential Marker of Aggressiveness in Lung Cancer.

Non-small cell lung cancer (NSCLC) is the leading cause of cancer death worldwide and cytology is often the only diagnostic approach. Na(+)/H(+) exchanger regulatory factor 1 (NHERF1) is a protein implicated in various cancers. However, the function of NHERF1 in lung cancer has not been described. The aim of this study was to evaluate the biological role of NHERF1 in lung tumors using fine needle aspirates cytology (FNAC) and to verify the utility and reliability of FNACs. We assessed NHERF1 expression by immunohistochemistry on 26 advanced NSCLC FNAC and on 18 surgical NSCLC samples. The relationship of its expression with clinicopathological features including stage and histotype was analyzed. In FNACs, cytoplasmic and nuclear NHERF1 expression was significantly higher than membranous expression. In surgical samples, cytoplasmic NHERF1 was significantly higher than both membranous and nuclear NHERF1 expression. In these tumors, a higher cytoplasmic and lower nuclear NHERF1 expression was observed compared to advanced NSCLCs (p < 0.0001, p < 0.05, respectively). In all 44 NSCLCs, a significant correlation was found between cytoplasmic NHERF1 expression and stage (p = 0.001), and between nuclear NHERF1 expression and histotype (p = 0.015). To our knowledge, this is the first study analyzing the immunohistochemical expression of NHERF1 in lung cancer using FNAC samples. We conclude that FNACs provide useful material for detection of NHERF1 localization and expression, and that high nuclear NHERF1 expression may be a potential marker of aggressiveness in NSCLC.