Interaction between viral proteins and hosts and its disturbance in the cellular responses to ionising radiation

Abstract

Purpose: Human malignant tumours are frequently found to be infected with a variety of viruses. The interaction of virus-encoded proteins with host cells proteins is highlighted in connection with the effect of viral proteins on DNA damage signalling and its impact on the sensitivity of cancer cells to ionising radiation.

Conclusion: The interaction of virus-encoded proteins with host cells not only plays an important role in viral infection and the consequential pathogenesis, but may also have an influence on the response of infected cancers to radiotherapy or chemotherapy. A series of viral proteins have already been demonstrated to interact with host proteins that are associated with cellular responses to DNA double-strand breaks, including DNA repair, apoptosis and cell cycle checkpoints, and this interaction results in mislocalisation, degradation, inactivation or activation of these host proteins. Some others directly or indirectly regulate the transcriptional level of a number of host genes or post-transcriptional modification of host proteins responding to ionising radiation, which leads to accumulation or downregulation of these gene products. These interactions between viral proteins and the hosts contribute to some extent to altered cellular radiosensitivity. Fully and accurately understanding the biological significance of viral infection to radiation will promote the future development of individualised strategies of cancer radiotherapy.

Keywords:

• Radiosensitivity
• DNA DSB repair
• cell cycle checkpoints
• apoptosis
• viral proteins
• DNA damage signalling