Lo et al. BMC Cancer 2012, 12:235 http://www.biomedcentral.com/1471-2407/12/235 about the gene copy number alterations common or dif- ferential in Caucasian and Asian lung cancer patients. Functional studies using cell, animal, and clinical models will be conducted to identify their cellular functions and etiological roles in lung tumorigenesis. Additional files Additional file 1: Table S1. Overall list of lung cancer patient in array- CGH, and candidate gene validations. Additional file 2: Table S2. The selected 18 chromosome regions investigated in the current array-CGH study. Additional file 3: Figure S1. Array image and schematic illustrations of the Bayes regression approach for identifying the regions with chromosomal copy number changes. Additional file 4: Table S3. Primers and PCR conditions used in the current study. Additional file 5: Table S4. List of candidate genes in Asian and Caucasian lung cancer patients. Additional file 6: Table S5. Association between mRNA expression level and lung cancer clinicopathological parameters of four candidate genes in Asian. Abbreviations array-CGH: Array-comparative genomic hybridization; qPCR: Quantitative polymerase chain reaction; ADC: Adenocarcinoma; BAC: Bacterial artificial chromosomes; NSCLC: Non-small cell lung cancer; RT-qPCR: Reverse transcriptase-qPCR; LOH: Loss of heterozygosity; DAVID: Database for Annotation, Visualization and Integrated Discovery. Competing interests The authors declare that they have no competing interests. Authors’ contributions YCW and FYL designed this study. FYL and JWC performed research. ISC, FUT, and SSJ analyzed array data. HSH, RK, SN, and RS provided clinical samples. YCW ,YJC, and SFH provided experimental materials. YCW and FYL wrote the manuscript. All authors read and approved the final manuscript. Acknowledgments This work was supported in part by grant NSC99-2628-B-006-004-MY3 from the National Science Council and landmark project A0012 from the National Cheng Kung University (YCW), by grant NSC100-2319-B-004-001 (ISC) and also supported by NCI 5R01CA125541-04 and 5R01CA129501-03 (RS). Study sponsors had no involvement on study design, analysis and interpretation of data, and decision on the submitted manuscript. We thank the Bioinformatics Center of National Cheng-Kung University for providing the MetaCore™ analysis software. We also thank Dr. Jing-Jou Yan (Pathology Department, National Cheng-Kung University) for IHC data interpretation. Author details 1Department of Pharmacology and Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, No.1, University Road, Tainan 701, Taiwan. 2Institute of Cancer Research, National Health Research Institutes, Miaoli, Taiwan. 3Department of Life Sciences and Institute of Genome Sciences, National Yang Ming University, Taipei, Taiwan. 4Institute of Emergency and Critical Care Medicine, National Yang Ming University and Division of Thoracic Surgery, Taipei Veterans General Hospital, Taipei, Taiwan. 5Division of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli, Taiwan. 6Department of Medicine, Cancer Research Center, The University of Chicago Medical Center, Pritzker School of Medicine, Chicago, IL, USA. Received: 15 December 2011 Accepted: 12 May 2012 Published: 12 June 2012 Page 12 of 13 References 1. 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