Viral lymphomas: can antivirals be used to treat cancer?

Current knowledge suggests that EBV, KSHV and HTLV-1 contribute to lymphomagenesis by subverting the host-cell molecular signaling machinery to deregulate cell growth and survival. Some signaling pathways that are affected by these viruses are well characterized, such as the NF-kB pathway, which is activated by these three viruses to promote cellular survival by inhibiting apoptosis, thereby playing a critical role in tumorigenesis. Other pathways, such as MTOR and JAK-STAT are also likely involved in viral lymphomagenesis. This provides the opportunity to inhibit these cellular pathways using drugs developed for the treatment of other malignancies. However, since these compounds target cellular proteins, they always have the potential for toxicity. In the context of viral malignancies, we have the unique opportunity of targeting viral proteins, and developing completely specific therapies. Here we will examine the question of whether the pathobiology of EBV, KSHV and HTLV-1 will allow the use of such an approach.