title: Infrared laser pulse triggers increased singlet oxygen production in tumour cells.
abstract: Photodynamic therapy (PDT) is a technique developed to treat the ever-increasing global incidence of cancer. This technique utilises singlet oxygen ((1)O2) generation via a laser excited photosensitiser (PS) to kill cancer cells. However, prolonged sensitivity to intensive light (6-8 weeks for lung cancer), relatively low tissue penetration by activating light (630 nm up to 4 mm), and the cost of PS administration can limit progressive PDT applications. The development of quantum-dot laser diodes emitting in the highest absorption region (1268 nm) of triplet oxygen ((3)O2) presents the possibility of inducing apoptosis in tumour cells through direct (3)O2 → (1)O2 transition. Here we demonstrate that a single laser pulse triggers dose-dependent (1)O2 generation in both normal keratinocytes and tumour cells and show that tumour cells yield the highest (1)O2 far beyond the initial laser pulse exposure. Our modelling and experimental results support the development of direct infrared (IR) laser-induced tumour treatment as a promising approach in tumour PDT.
authors: Photonics and Nanoscience Group, School of Engineering, Physics and Mathematics, University of Dundee, Dundee DD1 4HN, UK.
authors: S G
authors: SG
authors: Sokolovski
authors: Photonics and Nanoscience Group, School of Engineering, Physics and Mathematics, University of Dundee, Dundee DD1 4HN, UK.
authors: S A
authors: SA
authors: Zolotovskaya
authors: Centre for Research in Informatics and Systems Pathology (CRISP), University of Abertay Dundee, DD1 1HG, UK.
authors: A
authors: A
authors: Goltsov
authors: Division of Cancer Research, Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY, UK.
authors: C
authors: C
authors: Pourreyron
authors: Division of Cancer Research, Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY, UK.
authors: A P
authors: AP
authors: South
authors: Photonics and Nanoscience Group, School of Engineering, Physics and Mathematics, University of Dundee, Dundee DD1 4HN, UK.
authors: E U
authors: EU
authors: Rafailov
mesh_terms: D002118:Calcium / Q000378:metabolism; D016923:Cell Death / Q000528:radiation effects; D045744:Cell Line, Tumor; D006801:Humans; D007259:Infrared Rays / Q000009:adverse effects*; D007834:Lasers / Q000009:adverse effects*; D008027:Light; D009369:Neoplasms / Q000378:metabolism*; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism; D026082:Singlet Oxygen / Q000378:metabolism*; D012996:Solutions / Q000737:chemistry
chemical_list: D017382:Reactive Oxygen Species; D012996:Solutions; D026082:Singlet Oxygen; D002118:Calcium