PMID- 17608862
OWN - NLM
STAT- MEDLINE
DCOM- 20071003
LR  - 20101118
IS  - 0815-9319 (Print)
IS  - 0815-9319 (Linking)
VI  - 22
IP  - 7
DP  - 2007 Jul
TI  - Low-molecular-weight protein (LMP)2/LMP7 abnormality underlies the downregulation 
      of human leukocyte antigen class I antigen in a hepatocellular carcinoma cell 
      line.
PG  - 1155-61
AB  - BACKGROUND: Tumor cells may alter the expression of numerous components involved 
      in antigen-processing machinery to decrease human leukocyte antigen (HLA) class I 
      expression, allowing the tumor cells to escape immune surveillance. The purpose 
      of the present study was to investigate the involvement of these components in 
      the downregulation of HLA class I expression in human hepatocellular carcinoma 
      cell line BEL7,404. METHODS: Expression of HLA-I and antigen presentation-related 
      genes were analyzed by flow cytometry and polymerase chain reaction. The HLA 
      class I-deficient BEL7,404 cell was transfected with the low-molecular-weight 
      protein (LMP) 2 and LMP7 gene and were analyzed by flow cytometry for restoration 
      of surface HLA class I expression. RESULTS: The BEL7,404 cells downregulated the 
      expression of HLA class I antigen and lacked expression of LMP2 and LMP7. 
      Interferon (IFN)-gamma treatment increased the expression of LMP2 but not LMP7. 
      The LMP2-transfected BEL7,404 cells or LMP2 and LMP7-cotransfected cells restored 
      surface HLA class I expression while LMP7-transfected cells did not. However, in 
      IFN-gamma-treated BEL7,404 cells, transfection with the LMP7 gene induced more 
      HLA class I expression than mock transfection. CONCLUSIONS: The LMP2 gene was 
      required for the expression of HLA class I molecules in BEL7,404. The LMP7 was 
      not the major reason for loss of HLA class I in BEL7,404 cells, although the 
      supply of exogenous LMP7 could increase surface expression of HLA class I 
      antigen.
FAU - Shen, Yu-Qing
AU  - Shen YQ
AD  - State Education Ministry Laboratory of Developmental Genes and Human Diseases, 
      Jiangsu Provincial Key Laboratory of Gene Diagnosis and Therapy, Genetics 
      Research Center, Southeast University Medical School, Nanjing, Jiangsu Province, 
      China.
FAU - Zhang, Jian-Qiong
AU  - Zhang JQ
FAU - Xia, Mei
AU  - Xia M
FAU - Miao, Feng-Qing
AU  - Miao FQ
FAU - Shan, Xiang-Nian
AU  - Shan XN
FAU - Xie, Wei
AU  - Xie W
LA  - eng
GR  - TW005900-01A2/TW/FIC NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
PT  - Research Support, Non-U.S. Gov't
PL  - Australia
TA  - J Gastroenterol Hepatol
JT  - Journal of gastroenterology and hepatology
JID - 8607909
RN  - 0 (Histocompatibility Antigens Class I)
RN  - 0 (Multienzyme Complexes)
RN  - 144416-78-4 (LMP-2 protein)
RN  - EC 3.4.22.- (Cysteine Endopeptidases)
RN  - EC 3.4.25.1 (LMP7 protein)
RN  - EC 3.4.25.1 (Proteasome Endopeptidase Complex)
SB  - IM
MH  - Carcinoma, Hepatocellular/*immunology
MH  - Cell Line, Tumor
MH  - Cysteine Endopeptidases/*physiology
MH  - *Down-Regulation
MH  - Histocompatibility Antigens Class I/*physiology
MH  - Humans
MH  - Leukocytes/*immunology
MH  - Liver Neoplasms/*immunology
MH  - Multienzyme Complexes/*physiology
MH  - Proteasome Endopeptidase Complex
EDAT- 2007/07/05 09:00
MHDA- 2007/10/04 09:00
CRDT- 2007/07/05 09:00
PHST- 2007/07/05 09:00 [pubmed]
PHST- 2007/10/04 09:00 [medline]
PHST- 2007/07/05 09:00 [entrez]
AID - JGH4421 [pii]
AID - 10.1111/j.1440-1746.2006.04421.x [doi]
PST - ppublish
SO  - J Gastroenterol Hepatol. 2007 Jul;22(7):1155-61. doi: 
      10.1111/j.1440-1746.2006.04421.x.