Deficiency in DNA Damage Repair Proteins Promotes Prostate Cancer Cell Migration through Oxidative Stress
Philippa Lantwin,
Adam Kaczorowski,
Cathleen Nientiedt,
Constantin Schwab,
Martina Kirchner,
Viktoria Schütz,
Magdalena Görtz,
Markus Hohenfellner,
Anette Duensing,
Albrecht Stenzinger,
Stefan Duensing
Affiliations
Philippa Lantwin
Molecular Urooncology, Department of Urology, University Hospital Heidelberg, Im Neuenheimer Feld 517, D-69120 Heidelberg, Germany
Adam Kaczorowski
Molecular Urooncology, Department of Urology, University Hospital Heidelberg, Im Neuenheimer Feld 517, D-69120 Heidelberg, Germany
Cathleen Nientiedt
Department of Medical Oncology, University Hospital Heidelberg, National Center for Tumor Diseases (NCT), Im Neuenheimer Feld 460, D-69120 Heidelberg, Germany
Constantin Schwab
Institute of Pathology, University Hospital Heidelberg, Im Neuenheimer Feld 224, D-69120 Heidelberg, Germany
Martina Kirchner
Institute of Pathology, University Hospital Heidelberg, Im Neuenheimer Feld 224, D-69120 Heidelberg, Germany
Viktoria Schütz
Department of Urology, University Hospital Heidelberg, National Center for Tumor Diseases (NCT), Im Neuenheimer Feld 420, D-69120 Heidelberg, Germany
Magdalena Görtz
Department of Urology, University Hospital Heidelberg, National Center for Tumor Diseases (NCT), Im Neuenheimer Feld 420, D-69120 Heidelberg, Germany
Markus Hohenfellner
Department of Urology, University Hospital Heidelberg, National Center for Tumor Diseases (NCT), Im Neuenheimer Feld 420, D-69120 Heidelberg, Germany
Anette Duensing
Department of Urology, University Hospital Heidelberg, National Center for Tumor Diseases (NCT), Im Neuenheimer Feld 420, D-69120 Heidelberg, Germany
Albrecht Stenzinger
Institute of Pathology, University Hospital Heidelberg, Im Neuenheimer Feld 224, D-69120 Heidelberg, Germany
Stefan Duensing
Molecular Urooncology, Department of Urology, University Hospital Heidelberg, Im Neuenheimer Feld 517, D-69120 Heidelberg, Germany
Introduction: DNA damage repair gene deficiency defines a subgroup of prostate cancer patients with early metastatic progression and unfavorable disease outcome. Whether deficiency in DNA damage repair genes directly promotes metastatic dissemination is not completely understood. Methods: The migratory behavior of prostate cancer cells was analyzed after siRNA-mediated knockdown of DNA damage repair and checkpoint proteins, including BRCA2, ATM, and others, using transwell migration assays, scratch assays and staining for F-actin to ascertain cell circularity. Cells deficient in BRCA2 or ATM were tested for oxidative stress by measuring reactive oxygen species (ROS). The effects of ROS inhibition on cell migration were analyzed using the antioxidant N-acetylcysteine (NAC). The correlation between BRCA2 deficiency and oxidative stress was ascertained via immunohistochemistry for methylglyoxal (MG)-modified proteins in 15 genetically defined primary prostate cancers. Results: Prostate cancer cells showed a significantly increased migratory activity after the knockdown of BRCA2 or ATM. There was a significant increase in ROS production in LNCaP cells after BRCA2 knockdown and in PC-3 cells after BRCA2 or ATM knockdown. Remarkably, the ROS scavenger NAC abolished the enhanced motility of prostate cancer cells after the knockdown of BRCA2 or ATM. Primary prostate cancers harboring genetic alterations in BRCA2 showed a significant increase in MG-modified proteins, indicating enhanced oxidative stress in vivo. Conclusions: Our results indicate that DNA damage repair gene deficiency may contribute to the metastatic dissemination of prostate cancer through enhanced tumor cell migration involving oxidative stress.
