Proteomic Analysis of Primary Lung Cancer Aimed at Clinical Application

Abstract

Proteomic analysis is a comprehensive analysis of proteins. Recent advances in this field enable its application to clinical samples including surgically resected specimens and body fluids. In clinical applications its main techniques consist of 2-dimensional polyacrylamide gel electrophoresis (2-DE) and mass spectrometry (MS). Using 2-DE and surgically resected lung cancer specimens we identified napsin A, which was specific for primary lung adenocarcinoma, and reticulocalbin, which was related to resistance to platinum-based adjuvant chemotherapy. Furthermore, using MS we attempted to explore biomarkers for the selection of postoperative adjuvant chemotherapy with uracil-tegafur (PAC), and clarified that patients with no expression of either vimentin or myosin IIA showed a significantly better outcome, regardless of PAC. Though we hope that proteomic technology will contribute to the establishment of both a new screening method for the early detection and individualized therapy of lung cancer, several technical issues for the investigation of clinical samples have not yet been resolved. The main issues concern the dynamic range for analysis of clinical samples. It is important that the purpose of the proteomic analysis is clarified, and appropriate sample preparation suited for the purpose is essential.