Abstract
Kaposi's sarcoma (KS) herpesvirus (KSHV) is the etiological agent of several immunodeficiency-linked cancers, including KS. Our previous work showed that the proto-oncogene c-kit is upregulated in KSHV-infected endothelial cells (ECs), as well as in KS lesions. We show here that KSHV-dependent induction of both c-kit mRNA and protein requires the establishment of a latent infection and that this upregulation occurs in primary DMVECs as well as in immortalized DMVECs (eDMVECs). Interestingly, we find that while the lymphatic EC (LEC) subpopulation exhibits KSHV-induced c-Kit upregulation, the blood EC (BEC) subpopulation does not. Despite this upregulation of c-Kit, receptor activation and phosphorylation of downstream effectors such as MAP Kinase Erk 1/2 and GSK-3 still requires the addition of exogenous c-Kit ligand, stem cell factor (SCF). These data indicate that KSHV does not induce constitutive c-Kit signaling, but instead upregulates c-Kit receptor levels, thus allowing infected ECs to respond to endogenous and exogenous SCF. Nonetheless, inhibition of either c-Kit activation or its downstream effectors reverses the characteristic spindle phenotype of infected eDMVECs. Together, these results contribute to our overall understanding of the role that the c-kit proto-oncogene plays in KS pathogenesis.
Original language | English (US) |
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Pages (from-to) | 174-185 |
Number of pages | 12 |
Journal | Virology |
Volume | 390 |
Issue number | 2 |
DOIs | |
State | Published - Aug 1 2009 |
Keywords
- Endothelial cells
- Herpesvirus 8
- KSHV
- Kaposi's sarcoma
- Viral transformation
- c-kit
ASJC Scopus subject areas
- Virology