| Summary: | 碩士 === 國立陽明大學 === 醫學生物技術暨檢驗學系暨研究所 === 99 === Lung cancer has been one of the most serious cancer problems in the world for many years. Based on microscopic appearance, lung cancers can be divided into two main types: small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). Because of poor prognosis, lacking adequate screening and early detection measures, lung cancer has high mortality rate and only about 2% of those diagnosed with lung cancer that has spread to other areas of the body are alive for five years after the diagnosis. Standard treatments for lung cancer include surgical resection, chemotherapy, and radiation therapy. Although various chemotherapeutic agents reached a therapeutic plateau with the response rate of 30-40%, a new treatment approach was developed specifically focused on certain molecular pathways. Currently, the main forms of targeted therapy agents are (a) small molecule inhibitors and (b) monoclonal antibodies. In this study, high-throughput proteomic based on mass spectrometer technology was used to identify potential therapeutic targets of lung cancer. Stable isotope labeling with amino acids in cell culture (SILAC) based quantitation was also utilized for comparative analysis of (i) lung cancer cell membrane with soluble proteomes and (ii) lung cancer cell membrane proteomes of metastatic CL1-5 with non-metastatic CL1-0. In total we identified 475 and 521 proteins (3,772 and 4,517 peptides, respectively) in CL1-0 and CL1-5, respectively proteomes. Approximately 127 and 134 proteins were enriched in membrane fraction of CL1-0 and CL1-5, respectively by quantitative analysis. These proteins were applied to STRAP for information of subcellular locations, 31 of 127 proteins were assigned to cell surface protein in CL1-0 and 32 of 134 in CL1-5. To find metastasis-related membrane proteins, the relative levels of SILAC-labeled CL1-0 (light) and CL1-5 (heavy) membrane proteins were analyzed. About 650 proteins (13,590 peptides) were identified and 185 of 650 proteins were assigned to plasma membrane. The number of 1.5-fold up-regulated and down-regulated membrane proteins in CL1-5 is 37 and 77, respectively. On the other hand, analysis of lung cancer cell CL1-5 membrane proteome using label-free proteomic approach. A total of 549 proteins (3,094 peptides) were identified in CL1-5 membrane proteome, 149 of 549 proteins assigned to plasma membrane and cell surface. Finally, candidates were identified by comprehensive analysis of MS-identified proteins and up-regulated genes in public lung cancer microarray. It is interesting of four candidates, SERCA2 (sarcoplasmic/endoplasmic reticulum calcium ATPase 2, encoded by ATP2A2), citrin (encoded by SLC25A13), GalNAc-T2 (polypeptide N-acetylgalactosaminyltransferase 2, encoded by GALNT2) and mortalin (encoded by HSPA9), which were identified in this study. It was reported that some candidates highly associated with cancer or non-cancer disease. These candidates must be further analysis for their physiological significance and the roles in cancer progression.
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