UV light killing efficacy of fluorescent protein-expressing cancer cells in vitro and in vivo.
We investigated the cell-killing efficacy of UV light on cancer cells expressing GFP in the nucleus and RFP in the cytoplasm (dual-color cells). After exposure to various doses of UVA, UVB, or UVC, apoptotic and viable cells were quantitated under fluorescence microscopy using dual-color 143B human osteosarcoma cells, HT-1080 human fibrosarcoma cells, Lewis lung carcinoma (LLC), and XPA-1 human pancreatic cancer cells in vitro. UV-induced cancer cell death was wave-length and dose dependent, as well as cell-line dependent. After UVA exposure, most cells were viable even when the UV dose was increased up to 200 J/m(2). With UVB irradiation, cell death was observed with irradiation at 50 J/m(2). For UVC, as little as 25 J/m(2) UVC irradiation killed approximately 70% of the 143B dual-color cells. This dose of UVB or UVA had almost no effect on the cancer cells. UV-induced cancer cell death varied among the cell lines. Cell death began about 4 h after irradiation and continued until 10 h after irradiation. UVC exposure also suppressed cancer cell growth in nude mice in a model of minimal residual cancer (MRC). No apparent side effects of UVC exposure were observed. This study opens up the possibility of UVC treatment for MRC after surgical resection.
Kimura
Hiroaki
H
AntiCancer, Inc., 7917 Ostrow Street, San Diego, California 92111, USA.
Lee
Claudia
C
Hayashi
Katsuhiro
K
Yamauchi
Kensuke
K
Yamamoto
Norio
N
Tsuchiya
Hiroyuki
H
Tomita
Katsuro
K
Bouvet
Michael
M
Hoffman
Robert M
RM
D000818:Animals; D017209:Apoptosis / Q000528:radiation effects*; D018827:Carcinoma, Lewis Lung / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008819:Mice, Nude; D008856:Microscopy, Fluorescence; D009369:Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D047368:Tumor Burden / Q000528:radiation effects; D014466:Ultraviolet Rays; D000097573:Red Fluorescent Protein
D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins; D000097573:Red Fluorescent Protein