Kaposi's Sarcoma Herpesvirus Is Associated with Osteosarcoma in Xinjiang Uyghur Population

Osteosarcoma is the most common malignant tumor of bone predominately affecting adolescents and young adults. Viral etiology of osteosarcoma has been proposed more than a half-century ago but never been proven by identifying any virus authentically associated with human osteosarcoma. The Uyghur ethnic population in Xinjiang China has an unusually high prevalence of Kaposi9s sarcoma-associated herpesvirus (KSHV) infection and elevated incidence of osteosarcoma. In the current study, we explored the possible association of KSHV infection and osteosarcoma occurrence. Our seroepidemiological study revealed that KSHV prevalence was significantly elevated in osteosarcoma patients versus the general population in the Xinjiang Uyghur population (OR, 10.23; 95%CI, 4.25, 18.89). The KSHV DNA genome and viral latent nuclear antigen LANA were detected in most osteosarcoma tumor cells. Gene expression profiling analysis showed that KSHV positive osteosarcoma represents a distinct subtype of osteosarcomas with viral gene-driven signaling pathways that are important for osteosarcoma development. We conclude that KSHV infection is a risk factor for osteosarcoma and KSHV is associated with some osteosarcomas, representing a newly identified viral-associated endemic cancer. Significance: Viral etiology of osteosarcoma was proposed previously but has never been proven by identifying any virus that is authentically associated with human osteosarcoma. The current study revealed an association of human osteosarcoma with KSHV infection in Uyghur osteosarcoma patients. First, this study provides the first evidence that supports the possible viral etiology of human osteosarcoma. The gene expression profiling study showed that KSHV-positive osteosarcoma represents a distinct subtype of osteosarcomas, which is of diagnostic, prognostic and therapeutic significance. Second, KSHV-associated osteosarcomas preferentially occur in children and young adults, predicting that KSHV-positive children in KSHV endemic region may be at great risk for osteosarcoma. Third, the finding extended the range of human cancers associated with viruses.