TYR as a multifunctional reporter gene regulated by the Tet-on system for multimodality imaging: an in vitro study.
The human tyrosinase gene TYR is a multifunctional reporter gene with potential use in photoacoustic imaging (PAI), positron emission tomography (PET), and magnetic resonance imaging (MRI). We sought to establish and evaluate a reporter gene system using TYR under the control of the Tet-on gene expression system (gene expression induced by doxycycline [Dox]) as a multimodality imaging agent. We transfected TYR into human breast cancer cells (MDA-MB-231), naming the resulting cell line 231-TYR. Using non-transfected MDA-MB-231 cells as a control, we verified successful expression of TYR by 231-TYR after incubation with Dox using western blot, cellular tyrosinase activity, Masson-Fontana silver staining, and a cell immunofluorescence study, while the control cells and 231-TYR cells without Dox exposure revealed no TYR expression. Detected by its absorbance at 405 nm, increasing concentrations of melanin correlated positively with Dox concentration and incubation time. TYR expression by Dox-induced transfected cells shortened MRI T1 and T2 relaxation times. Photoacoustic signals were easily detected in these cells. (18)F-5-fluoro-N-(2-[diethylamino]ethyl)picolinamide ((18)F-5-FPN), which targets melanin, quickly accumulated in Dox-induced 231-TYR cells. These show that TYR induction of melanin production is regulated by the Tet-on system, and TYR-containing indicator cells may have utility in multimodality imaging.
Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology; Hubei Key Laboratory of Molecular Imaging, Wuhan 430022, China.
Hongyan
H
Feng
Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology; Hubei Key Laboratory of Molecular Imaging, Wuhan 430022, China.
Xiaotian
X
Xia
Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology; Hubei Key Laboratory of Molecular Imaging, Wuhan 430022, China.
Chongjiao
C
Li
Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology; Hubei Key Laboratory of Molecular Imaging, Wuhan 430022, China.
Yiling
Y
Song
Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology; Hubei Key Laboratory of Molecular Imaging, Wuhan 430022, China.
Chunxia
C
Qin
Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology; Hubei Key Laboratory of Molecular Imaging, Wuhan 430022, China.
Yongxue
Y
Zhang
Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology; Hubei Key Laboratory of Molecular Imaging, Wuhan 430022, China.
Xiaoli
X
Lan
D002460:Cell Line; D004318:Doxycycline / Q000494:pharmacology*; D005455:Fluorescent Antibody Technique; D005786:Gene Expression Regulation / Q000187:drug effects*; D017930:Genes, Reporter; D005822:Genetic Vectors / Q000235:genetics; D006801:Humans; D066298:In Vitro Techniques; D016086:Lentivirus / Q000235:genetics; D008279:Magnetic Resonance Imaging / Q000379:methods; D008543:Melanins / Q000235:genetics / Q000378:metabolism; D057054:Molecular Imaging / Q000379:methods; D014442:Monophenol Monooxygenase / Q000235:genetics*; D064847:Multimodal Imaging / Q000379:methods*; D009876:Operon; D049268:Positron-Emission Tomography / Q000379:methods; D012097:Repressor Proteins / Q000378:metabolism*; D014161:Transduction, Genetic
D008543:Melanins; D012097:Repressor Proteins; C034811:tetracycline resistance-encoding transposon repressor protein; D014442:Monophenol Monooxygenase; D004318:Doxycycline