Genetic Risk Factor for Prostate Cancer
Abstract
NKX3.1 is a homeoprotein with prostate-specific expression in adults. Loss of NKX3.1 correlates with prostate cancer progression. NKX3.1 protein expression is reduced to varying degrees in virtually all primary prostate cancers. The NKX3.1 gene is affected by deletion and/or promoter hypermethylation in 90% of primary prostate cancers. NKX3.1 acts as a transcription factor by binding directly to DNA. NKX3.1 also complexes and coactivates other transcription factors such as serum response factor. We have now found that NKX3.1 complexes with the DNA unwinding enzyme topoisomerase I. NKX3.1 binds to topoisomerase I in a stoichiometric relationship and enhances scissile strand DNA cleavage by topoisomerase I. NKX3.1 does not affect religation of relaxed DNA by topoisomerase I. We also found that NKX3.1 mediates DNA damage repair after cells are exposed to gamma-irradiation. The effect on DNA repair is mediated in cooperation with topoisomerase I. Loss of NKX3.1 expression that occurs early in prostate cancer may predispose to DNA damage and thereby facilitate prostate cancer progression.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2005
- Accession Number
- ADA434784
Entities
People
- Edward P. Gelmann
Organizations
- Georgetown University