Expression of the WT1 Wilms' tumor gene by normal and malignant human melanocytes

✍ Scribed by Ulrich Rodeck; Anna Bossler; Csaba Kari; Christopher W. Humphreys; Tibor Györfi; Jürgen Maurer; Eckhard Thiel; Hans D. Menssen

• Publisher: John Wiley and Sons
• Year: 1994
• Tongue: French
• Weight: 668 KB
• Volume: 59
• Category: Article
• ISSN: 0020-7136
• DOI: 10.1002/ijc.2910590116

✦ Synopsis

Abstract

We report expression of the wt I (Wilms' tumor) gene by cultured human melanoma cells. Using RNA polymerase chain reaction analysis, wt I transcripts were detected in 7 of 9 melanoma cell lines but not in 5 normal melanocyte strains. In Northern blot analysis, steady‐state wt I mRNA levels were found in 2 of 4 melanoma lines but not in normal melanocytes. Sequence analysis of the wt I cDNA expressed by melanoma cell line WM 902‐B revealed the presence of 4 previously published splice variants but no evidence for mutations in the coding region. Previous work has shown that WT I modulates transcription after binding to the early growth response (EGR)‐I sites present in the platelet‐derived growth factor (PDGF)‐A chain promoter; the PDGF‐A chain gene is known to be expressed by various melanoma cell lines. Based on these findings, we studied the relationship of wt I and PDGF‐A chain gene expression in melanoma cell lines. Co‐expression of the wt I and the PDGF‐A chain genes was observed in 2 melanoma cell lines with mutated p53 but not in 2 melanoma cell lines with wild‐type p53; this result is consistent with a previous report showing that, in the context of absent or mutated p53, WTI acts as a transcriptional activator, whereas in the presence of wild‐type p53 it acts as a repressor.