title: NOS1-, NOS3-, PIK3CA-, and MAPK-pathways in skin following radiation therapy.
abstract: BACKGROUND
  Essential molecular pathways such as the MAPK pathway, NO system, or the influence of PIK3CA as an oncogene are known to regulate fundamental signalling networks. However, few knowledge about their role in the occurrence of wound healing disorders (WHD) following radiation therapy (RT) exists. This study aims to evaluate the expression profiles of specific molecular pathway marker genes.
  
  
  METHODS
  Expression profiles of the genes encoding MAPK, NOS1, NOS3, and PIK3CA were analyzed, by RT-PCR, in specimens from patients with and without a history of RT to the head and neck. Clinical data on the occurrence of cervical WHDs were analyzed.
  
  
  RESULTS
  Expression analysis of patients with postoperative WHDs revealed a significant increase in MAPK expression compared to the control group without occurrence of postoperative WHDs. PIK3CA showed a significantly increased expression in patients with a history of RT. Expression analysis of all other investigated genes did not reveal significant differences.
  
  
  CONCLUSIONS
  This current study is able to show the influence of RT on different molecular pathways. This underlines the crucial role of specific molecular networks, responsible for the occurrence of long-term radiation toxicity such as WHDs. Additional studies should be carried out to identify possible starting points for therapeutic interventions.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Technical University of Munich (TUM), Ismaninger Str. 22, D-81675 Munich, Germany.
authors.forename: Steffen
authors.initials: S
authors.lastname: Koerdt
authors.affiliation: Department of Oral and Maxillofacial Surgery, Technical University of Munich (TUM), Ismaninger Str. 22, D-81675 Munich, Germany.
authors.forename: Nadine
authors.initials: N
authors.lastname: Tanner
authors.affiliation: Department of Oral and Maxillofacial Surgery, Technical University of Munich (TUM), Ismaninger Str. 22, D-81675 Munich, Germany.
authors.forename: Niklas
authors.initials: N
authors.lastname: Rommel
authors.affiliation: Department of Oral and Maxillofacial Surgery, Technical University of Munich (TUM), Ismaninger Str. 22, D-81675 Munich, Germany.
authors.forename: Nils H
authors.initials: NH
authors.lastname: Rohleder
authors.affiliation: Department of Oral and Maxillofacial Surgery, Technical University of Munich (TUM), Ismaninger Str. 22, D-81675 Munich, Germany.
authors.forename: Gesche
authors.initials: G
authors.lastname: Frohwitter
authors.affiliation: Department of Oral and Maxillofacial Surgery, Heidelberg University Hospital, Im Neuenheimer Feld 400, D-69120 Heidelberg, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Ristow
authors.affiliation: Department of Oral and Maxillofacial Surgery, Technical University of Munich (TUM), Ismaninger Str. 22, D-81675 Munich, Germany.
authors.forename: Klaus-Dietrich
authors.initials: KD
authors.lastname: Wolff
authors.affiliation: Department of Oral and Maxillofacial Surgery, Technical University of Munich (TUM), Ismaninger Str. 22, D-81675 Munich, Germany.
authors.forename: Marco R
authors.initials: MR
authors.lastname: Kesting
keywords: MAPK; NOS; PCR; PIK3CA; Radiation therapy