The human gastric cancer-associated DNA polymerase β variant D160N is a mutator that induces cellular transformation

Katherine A Donigan1, Suzanne E Hile, Kristin A Eckert

  • 1Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT 06520, United States.

DNA Repair
|February 21, 2012
PubMed

Insights

Mutations in the DNA Polymerase β (Pol β) gene are found in many human tumors. The D160N variant acts as a mutator, driving complex mutations linked to cancer development and progression.

Area of Science:

  • Molecular Biology
  • Genetics
  • Oncology

Background:

  • Approximately 30% of human tumors exhibit mutations in the POLB gene.
  • Some POLB mutations result in enzymes with altered activity, promoting cellular transformation.

Purpose of the Study:

  • To investigate the functional impact of the DNA Polymerase β (Pol β) variant Asp160Asn (D160N).
  • To determine if D160N induces complex mutations and contributes to tumorigenesis.

Main Methods:

  • Expression of the D160N variant in cells.
  • Assessment of cellular transformation markers (hyperproliferation, focus formation, anchorage-independent growth, invasion).
  • Analysis of mutation types induced by D160N.

Main Results:

  • D160N expression induced cellular transformation phenotypes.
  • D160N was identified as an active mutator polymerase.
  • D160N generates complex mutations.

Conclusions:

  • Complex mutagenesis driven by the D160N Pol β variant is a mechanism underlying observed cellular phenotypes.
  • These phenotypes are linked to tumorigenesis and tumor progression.

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