title: Suppression subtractive hybridization identified differentially expressed genes in lung adenocarcinoma: ERGIC3 as a novel lung cancer-related gene.
abstract: BACKGROUND
  To understand the carcinogenesis caused by accumulated genetic and epigenetic alterations and seek novel biomarkers for various cancers, studying differentially expressed genes between cancerous and normal tissues is crucial. In the study, two cDNA libraries of lung cancer were constructed and screened for identification of differentially expressed genes.
  
  
  METHODS
  Two cDNA libraries of differentially expressed genes were constructed using lung adenocarcinoma tissue and adjacent nonmalignant lung tissue by suppression subtractive hybridization. The data of the cDNA libraries were then analyzed and compared using bioinformatics analysis. Levels of mRNA and protein were measured by quantitative real-time polymerase chain reaction (q-RT-PCR) and western blot respectively, as well as expression and localization of proteins were determined by immunostaining. Gene functions were investigated using proliferation and migration assays after gene silencing and gene over-expression.
  
  
  RESULTS
  Two libraries of differentially expressed genes were obtained. The forward-subtracted library (FSL) and the reverse-subtracted library (RSL) contained 177 and 59 genes, respectively. Bioinformatic analysis demonstrated that these genes were involved in a wide range of cellular functions. The vast majority of these genes were newly identified to be abnormally expressed in lung cancer. In the first stage of the screening for 16 genes, we compared lung cancer tissues with their adjacent non-malignant tissues at the mRNA level, and found six genes (ERGIC3, DDR1, HSP90B1, SDC1, RPSA, and LPCAT1) from the FSL were significantly up-regulated while two genes (GPX3 and TIMP3) from the RSL were significantly down-regulated (P < 0.05). The ERGIC3 protein was also over-expressed in lung cancer tissues and cultured cells, and expression of ERGIC3 was correlated with the differentiated degree and histological type of lung cancer. The up-regulation of ERGIC3 could promote cellular migration and proliferation in vitro.
  
  
  CONCLUSIONS
  The two libraries of differentially expressed genes may provide the basis for new insights or clues for finding novel lung cancer-related genes; several genes were newly found in lung cancer with ERGIC3 seeming a novel lung cancer-related gene. ERGIC3 may play an active role in the development and progression of lung cancer.
authors: Key Laboratory of Animal Models and Human Disease Mechanism, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China.
authors: Mingsong
authors: M
authors: Wu
authors: Tao
authors: T
authors: Tu
authors: Yunchao
authors: Y
authors: Huang
authors: Yi
authors: Y
authors: Cao
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D000077192:Adenocarcinoma of Lung; D000328:Adult; D000368:Aged; D015153:Blotting, Western; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D019295:Computational Biology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D015723:Gene Library; D020022:Genetic Predisposition to Disease; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D008875:Middle Aged; D009693:Nucleic Acid Hybridization; D010641:Phenotype; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D014162:Transfection; D015854:Up-Regulation
chemical_list: C517615:ERGIC3 protein, human; D008565:Membrane Proteins; D012333:RNA, Messenger
references: Lung Cancer. 2007 Jun;56(3):307-17
references: 17316888
references: Proc Natl Acad Sci U S A. 1996 Jun 11;93(12):6025-30
references: 8650213
references: Science. 2006 Oct 13;314(5797):268-74
references: 16959974
references: Lab Invest. 2002 Nov;82(11):1515-24
references: 12429811
references: Eur J Cancer. 2003 Sep;39(13):1936-47
references: 12932674
references: Lung. 1997;175(5):321-32
references: 9270989
references: Mol Biol (Mosk). 2006 Nov-Dec;40(6):1047-54
references: 17209433
references: Mol Cancer. 2006 Aug 08;5:30
references: 16893473
references: Int J Cancer. 2008 Jul 1;123(1):1-7
references: 18425819
references: J Clin Oncol. 2008 Nov 1;26(31):5060-6
references: 18794547
references: Cancer Invest. 2009 May;27(4):453-8
references: 19212831
references: J Cell Sci. 2006 Nov 15;119(Pt 22):4730-40
references: 17077122
references: J Cell Biol. 2001 Feb 5;152(3):503-18
references: 11157978
references: EMBO J. 2002 Nov 15;21(22):6095-104
references: 12426381
references: Gene. 2007 Jan 15;386(1-2):42-51
references: 17020792
references: J Mol Med (Berl). 2009 Jan;87(1):85-97
references: 18974965
references: Cancer Lett. 2004 Aug 20;212(1):83-93
references: 15246564
references: Oncol Rep. 2010 Aug;24(2):311-9
references: 20596615
references: Oncogene. 2002 May 23;21(23):3814-25
references: 12032850
references: Proc Natl Acad Sci U S A. 2003 Apr 15;100(8):4586-91
references: 12663859
references: Nat Protoc. 2008;3(6):1101-8
references: 18546601
references: Oncogene. 2004 Oct 7;23(46):7734-45
references: 15334068
references: Eur Respir J. 2001 Dec;18(6):1059-68
references: 11829087
references: Proc Natl Acad Sci U S A. 2001 Nov 20;98(24):13554-9
references: 11698669
references: Mol Cancer. 2009 Sep 07;8:72
references: 19735553
references: Lung Cancer. 2001 Jun;32(3):297-305
references: 11390011
references: J Biol Chem. 2004 Nov 5;279(45):47242-53
references: 15308636