PT  - JOURNAL ARTICLE
AU  - Wei Li
AU  - Xiao-Mei Deng
AU  - Chuan-Xin Wang
AU  - Xiao Zhang
AU  - Gui-Xi Zheng
AU  - Jian Zhang
AU  - Jin-Bo Feng
TI  - Down-Regulation of HLA Class I Antigen in Human Papillomavirus Type 16 E7 Expressing HaCaT Cells: Correlate With TAP-1 Expression
AID  - 10.1111/IGC.0b013e3181cceec5
DP  - 2010 Feb 01
TA  - International Journal of Gynecologic Cancer
PG  - 227-232--227-232
VI  - 20
IP  - 2
4099  - http://ijgc.bmj.com/content/20/2/227-232.short
4100  - http://ijgc.bmj.com/content/20/2/227-232.full
SO  - Int J Gynecol Cancer2010 Feb 01; 20
AB  - Objectives: High-risk human papillomaviruses (HPVs) are the major causative agents of cervical cancer, and the E6 and E7 genes encode the major HPV oncoproteins. The E7 protein of high-risk HPV types disturbs cell cycle control and down-regulates components of the antigen presentation pathway, suggesting a role for E7 in tumor immune evasion. We previously reported that HPV-16 E7 expression and down-regulation of HLA class I was highly correlated in cervical lesions. This study was aimed to determine whether HPV-16 E7 oncoprotein could down-regulate surface HLA class I antigen in HPV-16 E7-transfected cells, and whether it had correlation with the expression of the transporter associated with antigen processing (TAP).Methods: The HPV-16 E7 open reading frame was transfected into HaCaT cells. After G418 selection, resistant colonies were individually picked and expanded into clonal cell lines. Using the fluoresence-activated cell sorting analysis, the levels of cell surface HLA class I antigen and intracellular TAP-1 and TAP-2 expressions were detected.Results Compared with the empty vector control, a statistical significant decrease of approximately 50% in cell surface HLA class I expression was observed in HPV-16 E7 expressing HaCaT cells (P < 0.001). Moreover, the expression of HPV-16 E7 in HaCaT cells resulted in decreased expression of TAP-1 that was essential for HLA class I expression at the cell surface, a statistical significant decrease of approximately 40% compared with that with the empty vector control (P < 0.001).Conclusions: Our finding demonstrates that HPV-16 E7 down-regulates surface HLA class I antigen, which in part correlates with the decrease of TAP-1.