The Cover

The alternative reading frame protein p14ARF is a small basic tumor suppressor expressed in the nucleus and nucleoli in response to oncogene activation or after loss of normal cell cycle control. The image shows scattered p14ARF positive cells (brown) by immunohistochemistry in a case of cervical carcinoma in situ counterstained with hematoxylin and eosin. In addition to nuclear staining some diffuse cytoplasmic reactivity can be seen. For details, see J.L. Wang et al., in this issue.