Fig. 5: The role of viral integration in multi-staged progression of tumor.

Different colors of the cell nucleus denote different integration status of virus. Nuclei with green background and diverse white stripes represent cells with new integration at other sites on the basis of an original integration. Blue nuclei represent normal cells without any viral integration; while the red, purple, black represent cells with different integration sites. The background of the cells with passenger integration or without new integration is blurred; these cells which are at disadvantage will disappear sooner or later depending on their volume. Normal cells with blue nuclei cannot be identified by virome capture sequencing in watch points due to the absence of integration sites.