Overexpression of xCT induces up-regulation of 14-3-3beta in Kaposi's sarcoma.
KSHV (Kaposi's sarcoma-associated herpesvirus), or HHV-8 (human herpesvirus 8), is associated with the pathogenesis of KS, the most common AIDS-related malignancy. xCT (functional subunit of the cystine/glutamate transporter xc- system) is known as the HHV-8 fusion-entry receptor as well as an oncogenic protein. How the xCT triggers the signal transduction of HHV-8 infection and the cell proliferation remains incomplete. We found that xCT was overexpressed in KS tissues and HHV-8-positive BCBL-1 cells. When xCT cDNA plasmids were transfected into the HHV-8-negative BJAB cells, the expression of 14-3-3beta and cell growth rate were increased. In contrast, the expression of 14-3-3beta and the cell growth rate of HHV-8-positive BCBL-1 cells were suppressed by either xCT siRNA (short interfering RNA) or an xCT inhibitor, sulfsalazine. These results suggest that 14-3-3beta is a downstream effector of xCT in KS to mediate the cell proliferation.
Zeng
Yan
Y
Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China.
Li
Yan
Y
Chen
Ri-Sheng
RS
He
Xin
X
Yang
Lei
L
Li
Wei
W
D048948:14-3-3 Proteins / Q000378:metabolism*; D027182:Amino Acid Transport System y+ / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D002460:Cell Line; D019288:Herpesvirus 8, Human / Q000235:genetics / Q000378:metabolism; D006801:Humans; D051379:Mice; D008822:Mice, Transgenic; D012514:Sarcoma, Kaposi / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation
D048948:14-3-3 Proteins; D027182:Amino Acid Transport System y+; C118895:SLC7A11 protein, human; C492255:Slc7a11 protein, mouse