Altered phosphatidylcholines expression in sputum for diagnosis of non-small cell lung cancer

// Jianyong Zhang 1, * , Jianjun Xu 1, * , Haiyan Lu 2 , Jianhua Ding 2 , Dongliang Yu 1 , Penghui Li 2 , Jianwen Xiong 1 , Xingxing Liu 2 , Huanwen Chen 2 , Yiping Wei 1 1 Department of Cardiothoracic Surgery, the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi Province 330006, P. R. China 2 Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, East China Institute of Technology, Nanchang, Jiangxi Province 330013, P. R. China * These authors contributed equally to this work Correspondence to: Yiping Wei, email: weiyip2000@hotmail.com Huanwen Chen, email: chw8868@gmail.com Keywords: NSCLC, sputum, phosphatidylcholines, ND-EESI-MS Received: March 30, 2016 Accepted: July 19, 2016 Published: August 13, 2016 ABSTRACT Non–small cell lung cancer (NSCLC) is a leading cause of cancer mortality worldwide, and early diagnosis needs to be improved. We examined whether neutral desorption extractive electrospray ionization mass spectrometry (ND-EESI-MS) could be used to detect sputum lipids expression changes to enable earlier diagnosis. Overall, 167 NSCLC patients and 140 controls were enrolled. The main peaks in the sputum of patients with NSCLC patients differed from controls (83.3% of total variability), and the signals were not associated with pathological type, TNM stage or smoking history. The relative abundance of peaks at m/z734, m/ z756, m/z772, m/z782, m/z798 and m/z803 reliably distinguished NSCLC sputum from control. Collision-induced dissociation confirmed that m/z734, m/z756, and m/z772 represented [DPPC + H] + , [DPPC + Na] + , and [DPPC + K] + , respectively, and m/z782, m/z798, and m/z803 represented sphingomyelin, phosphatidylglycerol, and phosphatidylglycerolphosphate, respectively. The relative abundance of DPPC was clearly lower in NSCLC sputum than in control, and the relative abundances of phosphatidylglycerol and phosphatidylglycerolphosphate were higher in NSCLC sputum than in control. The detection of changes in sputum lipids with ND-EESI-MS may be a noninvasive, radiation-free, relatively inexpensive, repeatable, and efficient method for diagnosis of NSCLC.