title: Recombinant lentivirus with enhanced expression of caudal-related homeobox protein 2 inhibits human colorectal cancer cell proliferation in vitro.
abstract: Caudal-related homeobox protein 2 (CDX2), a tumor suppressor in the adult colon, is overexpressed under a non-cancer specific cytomegalovirus promoter in certain tumor cells; furthermore, non-specific expression of CDX2 may result in aberrant side effects in normal cells. The human telomerase reverse transcriptase (hTERT) promoter is active in the majority of cancer cells but not in normal cells. Hypoxia is a key feature of solid tumors, and targeted genes may be significantly upregulated by five copies of hypoxia-response elements (HREs) under hypoxic conditions. However, the effect of CDX2 overexpression, as controlled by five copies of HREs and the hTERT promoter, on human colorectal cancer (CRC) cell proliferation in vitro remains to be fully elucidated. In the current study, a recombinant lentivirus containing the CDX2 gene under the control of five HREs and the hTERT promoter was generated. An immunofluorescence assay was used to detect CDX2 expression by the 5 HhC lentivirus, whereas an MTT assay was used to detect the effects of CoCl2 on the viability of LoVo cells. Western blot analysis was conducted in order to determine the relative ratios of recombinant CDX2 protein to the internal control β-actin, following 5 HhC/LoVo cell culture under normoxic and hypoxic conditions (100, 200, 300, 400 or 500 µmol/l CoCl2) for 24 h, then for 12, 24 or 36 h with the optimal concentration (300 µmol/l) of CoCl2. Reverse transcription polymerase chain reaction analysis was used to determine the transcription of recombinant CDX2 mRNA following culture of 5 HhC/LoVo cells under normoxic or hypoxic conditions. Finally, a cloning assay was used to detect the proliferative ability of 5 HhC/LoVo and 5 Hh cells. High CDX2 expression was observed in hTERT-positive LoVo cells under hypoxic conditions, an effect which was mimicked by treatment with CoCl2 to inhibit LoVo cell proliferation in vitro. High expression of CDX2 therefore provides a promising strategy for the development of novel targeted treatments and gene therapy for CRC.
authors.affiliation: Department of General Surgery, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China.
authors.forename: Sai
authors.initials: S
authors.lastname: He
authors.affiliation: Department of General Surgery, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China.
authors.forename: Xue-Jun
authors.initials: XJ
authors.lastname: Sun
authors.affiliation: Department of General Surgery, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China.
authors.forename: Jian-Bao
authors.initials: JB
authors.lastname: Zheng
authors.affiliation: Second Department of Cardiovascular Medicine, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710068, P.R. China.
authors.forename: Jie
authors.initials: J
authors.lastname: Qi
authors.affiliation: Department of General Surgery, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China.
authors.forename: Nan-Zheng
authors.initials: NZ
authors.lastname: Chen
authors.affiliation: Department of General Surgery, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Department of General Surgery, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China.
authors.forename: Guang-Bing
authors.initials: GB
authors.lastname: Wei
authors.affiliation: Department of General Surgery, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China.
authors.forename: Dong
authors.initials: D
authors.lastname: Liu
authors.affiliation: Department of General Surgery, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China.
authors.forename: Jun-Hui
authors.initials: JH
authors.lastname: Yu
authors.affiliation: Department of General Surgery, First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China.
authors.forename: Shao-Ying
authors.initials: SY
authors.lastname: Lu
authors.affiliation: Department of Anesthesiology, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710068, P.R. China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
mesh_terms: D000071616:CDX2 Transcription Factor; D015687:Cell Hypoxia; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D003035:Cobalt / Q000633:toxicity; D015179:Colorectal Neoplasms / Q000378:metabolism / Q000473:pathology; D005822:Genetic Vectors / Q000235:genetics / Q000378:metabolism*; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D016086:Lentivirus / Q000235:genetics*; D008856:Microscopy, Fluorescence; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000378:metabolism; D020218:Response Elements / Q000235:genetics; D019098:Telomerase / Q000235:genetics
chemical_list: D000071616:CDX2 Transcription Factor; C491270:CDX2 protein, human; D018398:Homeodomain Proteins; D012333:RNA, Messenger; D003035:Cobalt; C509186:TERT protein, human; D019098:Telomerase; C018021:cobaltous chloride
references.citation: J Transl Med. 2011;9:39
references.pmid: 21481255
references.citation: Langenbecks Arch Surg. 2015 Feb;400(2):129-43
references.pmid: 25701352
references.citation: J Cell Mol Med. 2010 Jan;14(1-2):18-29
references.pmid: 19840191
references.citation: Cancer Res. 2011 Jan 15;71(2):593-602
references.pmid: 21224344
references.citation: Nat Genet. 2003 Dec;35(4):323-30
references.pmid: 14625550
references.citation: Int J Mol Med. 2012 Nov;30(5):1173-9
references.pmid: 22960790
references.citation: Int J Oncol. 2010 Feb;36(2):509-16
references.pmid: 20043087
references.citation: Cell Signal. 2009 Dec;21(12):1846-56
references.pmid: 19686845
references.citation: Mol Cancer Res. 2011 Nov;9(11):1520-36
references.pmid: 21984181
references.citation: Am Surg. 2013 Apr;79(4):353-60
references.pmid: 23574843
references.citation: Hum Pathol. 2010 Oct;41(10):1438-47
references.pmid: 20709360
references.citation: J Pathol. 2010 Jan;220(1):87-96
references.pmid: 19806612
references.citation: J Biochem. 2012 May;151(5):477-81
references.pmid: 22496483
references.citation: Cancer Microenviron. 2008 Dec;1(1):69-83
references.pmid: 19308686
references.citation: Carcinogenesis. 2010 Feb;31(2):159-66
references.pmid: 19734199
references.citation: Magy Onkol. 2010 Dec;54(4):383-94
references.pmid: 21163770
references.citation: Exp Ther Med. 2012 Nov;4(5):859-864
references.pmid: 23226739
references.citation: Mol Ther. 2010 Feb;18(2):429-34
references.pmid: 19935775
references.citation: Oncogene. 2008 Jan 3;27(1):107-15
references.pmid: 17599044
references.citation: Pathol Oncol Res. 2011 Sep;17(3):743-51
references.pmid: 21626348
references.citation: Cell Death Dis. 2014;5:e1356
references.pmid: 25077542
references.citation: J Urol. 2013 Sep;190(3):1083-9
references.pmid: 23545100
references.citation: Mol Cell Endocrinol. 2010 Jan 15;314(1):118-27
references.pmid: 19628018
references.citation: Surg Oncol. 2014 Sep;23(3):167-76
references.pmid: 25126956
references.citation: Mol Cell Biochem. 2013 Apr;376(1-2):1-9
references.pmid: 23340976
references.citation: Int J Cancer. 2008 Jun 1;122(11):2628-33
references.pmid: 18338751
references.citation: Nature. 1997 Mar 6;386(6620):84-7
references.pmid: 9052785
references.citation: Br J Cancer. 2011 Jun 28;105(1):139-45
references.pmid: 21673686
references.citation: Mol Biol Rep. 2010 Oct;37(7):3239-47
references.pmid: 19876766
references.citation: Oncol Rep. 2010 Jul;24(1):97-104
references.pmid: 20514449
references.citation: Br J Cancer. 2007 Jun 18;96(12):1871-8
references.pmid: 17519901
references.citation: Eur J Pharm Biopharm. 2013 Sep;85(1):20-5
references.pmid: 23958315
references.citation: Carcinogenesis. 2013 Jun;34(6):1361-9
references.pmid: 23393221
references.citation: J Biol Chem. 2014 Nov 28;289(48):33343-54
references.pmid: 25320087
references.citation: Mol Med Rep. 2009 Nov-Dec;2(6):1017-22
references.pmid: 21475937
references.citation: Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi. 2010 Jun;26(6):525-9
references.pmid: 20487641
references.citation: Cell Biochem Biophys. 2014 Apr;68(3):463-73
references.pmid: 24078401