Selective destruction of transformed cells by reovirus: Cellular targets and active reovirus proteins analysis

It is known that Reovirus selectively destroys transformed cells, but the complex mechanism is not completely understood at this time. In this study, gene expression was examined by comparing Reovirus-infected SV-40 transformed human embryonic fibroblasts, with mock-infected cells. Among the 40 genes shown to be altered, 38 genes were up regulated, and 2 genes were down regulated. Out of the 40 genes having differential gene expression, 8 were significantly over induced. 3 of these were DNA binding transcription factors. Activation of transcription factors following Reovirus infection suggests that gene expression is essential in Reovirus induced transformed cell killing. Another 3 genes were found to be tumor suppressor proteins and oncogenes expressed downstream of the Ras pathway. The over expression of these was shown to induce apoptosis induced cell killing by Reovirus. Finally, 2 of the 8 significantly up regulated genes cause cell cycle progression inhibition. The cell cycle arrest then leads to cell death.