Targeting nonhomologous end-joining through epidermal growth factor receptor inhibition: rationale and strategies for radiosensitization.
DNA double-strand breaks (DSBs) are the most lethal type of DNA damage induced by ionizing radiation or chemotherapeutic drugs used to eradicate cancer cells. The ability of cancer cells to effectively repair DSBs significantly influences the outcome of therapeutic regimens. Therefore, a new and important area of clinical cancer research is the development of DNA repair inhibitors that can be used as radio- or chemosensitizers. Nonhomologous end joining (NHEJ) is the predominant pathway for the repair of radiation-induced DSBs. A series of recent reports indicates that the epidermal growth factor receptor (EGFR) or its downstream components may modulate NHEJ through direct interaction with the DNA repair enzyme, DNA-dependent protein kinase. Because EGFR is overexpressed or activated in many cancers, these findings provide a compelling rationale for combining radiotherapy with therapies that block EGFR or its downstream signaling components. In this review, we delineate how these novel connections between a cell-surface receptor (EGFR) and a predominantly nuclear event (NHEJ) provide vulnerable nodes that can be selectively targeted to improve cancer therapy.
Mukherjee
Bipasha
B
Division of Molecular Radiation Biology, Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas 75390, TX, USA.
Choy
Hak
H
Nirodi
Chaitanya
C
Burma
Sandeep
S
D002453:Cell Cycle; D053903:DNA Breaks, Double-Stranded / Q000187:drug effects* / Q000528:radiation effects*; D004249:DNA Damage; D004260:DNA Repair; D045643:DNA Repair Enzymes / Q000187:drug effects / Q000528:radiation effects; D004273:DNA, Neoplasm / Q000187:drug effects / Q000528:radiation effects; D066246:ErbB Receptors / Q000037:antagonists & inhibitors*; D006801:Humans; D009369:Neoplasms / Q000188:drug therapy* / Q000532:radiotherapy*; D018787:Radiation Oncology / Q000379:methods; D011838:Radiation-Sensitizing Agents / Q000494:pharmacology*; D011995:Recombination, Genetic; D015398:Signal Transduction / Q000187:drug effects / Q000528:radiation effects
D004273:DNA, Neoplasm; D011838:Radiation-Sensitizing Agents; D066246:ErbB Receptors; D045643:DNA Repair Enzymes