title: A novel approach to a bifunctional photosensitizer for tumor imaging and phototherapy.
abstract: Optical imaging has attracted a great attention for studying molecular recognitions because minute fluorescent tracers can be detected in homogeneous and heterogeneous media with existing laboratory instruments. In our preliminary study, a clinically relevant photosensitizer (HPPH, a chlorophyll-a analog) was linked with a cyanine dye (with required photophysical characteristics but limited tumor selectivity), and the resulting conjugate was found to be an efficient tumor imaging (fluorescence imaging) and photosensitizing agent. Compared to HPPH, the presence of the cyanine dye moiety in the conjugate produced a significantly higher uptake in tumor than skin. At a therapeutic/imaging dose, the conjugate did not show any significant skin phototoxicity, a major drawback associated with most of the porphyrin-based photosensitizers. These results suggest that tumor-avid porphyrin-based compounds can be used as "vehicles" to deliver the desired fluorescent agent(s) to tumor. The development of tumor imaging or improved photodynamic therapy agent(s) by itself represents an important step, but a dual function agent (fluorescence imaging and photodynamic therapy) provides the potential for tumor detection and targeted photodynamic therapy, combining two modalities into a single cost-effective "see and treat" approach.
authors.affiliation: PDT Center, Cell Stress Biology, Roswell Park Cancer Institute, Buffalo, New York 14263, USA.
authors.forename: Yihui
authors.initials: Y
authors.lastname: Chen
authors.forename: Amy
authors.initials: A
authors.lastname: Gryshuk
authors.forename: Samuel
authors.initials: S
authors.lastname: Achilefu
authors.forename: Tymish
authors.initials: T
authors.lastname: Ohulchansky
authors.forename: William
authors.initials: W
authors.lastname: Potter
authors.forename: Tuoxiu
authors.initials: T
authors.lastname: Zhong
authors.forename: Janet
authors.initials: J
authors.lastname: Morgan
authors.forename: Britton
authors.initials: B
authors.lastname: Chance
authors.forename: Paras N
authors.initials: PN
authors.lastname: Prasad
authors.forename: Barbara W
authors.initials: BW
authors.lastname: Henderson
authors.forename: Allan
authors.initials: A
authors.lastname: Oseroff
authors.forename: Ravindra K
authors.initials: RK
authors.lastname: Pandey
mesh_terms: D000818:Animals; D002460:Cell Line; D004285:Dogs; D051379:Mice; D015394:Molecular Structure; D009369:Neoplasms / Q000098:blood supply / Q000175:diagnosis* / Q000188:drug therapy*; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000737:chemistry* / Q000494:pharmacology / Q000627:therapeutic use*; D012867:Skin / Q000187:drug effects; D013057:Spectrum Analysis; D023041:Xenograft Model Antitumor Assays
chemical_list: D017319:Photosensitizing Agents