Apurinic/apyrimidinic endonuclease expression in pediatric yolk sac tumors.
BACKGROUND
The enzyme apurinic/apyriminidic endonuclease/redox factor 1 (Ape1/ref1), a key protein in the base excision repair pathway, displays repair and redox activity. We examined the role of Ape1/ref1 and a protein it regulates, hypoxia inducible factor 1 alpha (HIF-1 alpha) in pediatric yolk sac tumors.


METHODS
Using an immunohistochemical evaluation, 16 pediatric yolk sac tumors were evaluated for Ape1/ref1 and HIF-1 alpha expression. Samples were obtained from archival tissue.


RESULTS
We demonstrated high levels of expression of Ape1/ref1 in 14/16 of the tumors. This expression was limited to the nucleus of the viable portion of each tumor. High levels of HIF-1 alpha expression was noted in half of the same tumors and localized to both the nucleus and cytoplasm of the viable tumor.


CONCLUSIONS
The high levels of expression of Ape1/ref1 in this group of chemosensitive tumors may be related to the subcellular location or redox regulatory activity of one of the other factors controlled by Ape1/ref1.
Thomson
B G
BG
Indiana University School of Medicine, Department of Pediatric Hematology/Oncology, Indianapolis, IN, USA. bthomson@iupui.edu
Tritt
R
R
Davis
M
M
Perlman
E J
EJ
Kelley
M R
MR
D019757:Carbon-Oxygen Lyases / Q000032:analysis*; D002675:Child, Preschool; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase; D004268:DNA-Binding Proteins / Q000032:analysis; D018240:Endodermal Sinus Tumor / Q000201:enzymology*; D005260:Female; D006801:Humans; D051793:Hypoxia-Inducible Factor 1; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009363:Neoplasm Proteins / Q000032:analysis*; D009687:Nuclear Proteins / Q000032:analysis; D014157:Transcription Factors / Q000032:analysis
D004268:DNA-Binding Proteins; C497442:HIF1A protein, human; D051793:Hypoxia-Inducible Factor 1; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D014157:Transcription Factors; D019757:Carbon-Oxygen Lyases; C085108:APEX1 protein, human; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase