Human c-myc transcription factor PuF identified as nm23-H2 nucleoside diphosphate kinase, a candidate suppressor of tumor metastasis.

A human gene encoding the c-myc purine-binding transcription factor PuF was identified by screening of a cervical carcinoma cell complementary DNA library with a DNA fragment containing PuF binding sites. The 17-kilodalton bacterially produced PuF was shown to have biological activity and properties similar to that of human PuF. DNA sequence analysis of recombinant PuF revealed perfect identity with the human nm23-H2 nucleoside diphosphate kinase gene, a potential negative regulator of cancer metastasis. These results provide a link between nm23 and the c-myc oncogene and suggest that the nm23 protein can function in vitro in the transcriptional regulation of c-myc expression.