title: In Vivo Cancer Dual-Targeting and Dual-Modality Imaging with Functionalized Quantum Dots.
abstract: Semiconductor quantum dots (QDs), after surface modification to provide water solubility and biocompatibility, have a promising future in biomedical applications. In this study, a dual receptor-targeting dual-modality PET/near-infrared fluorescence (NIRF) probe was developed for accurate assessment of the pharmacokinetics and tumor-targeting efficacy of QDs.
  
  
  METHODS
  QDs were modified by β-Glu-RGD-BBN (RGD is arginine-glycine-aspartate acid, and BBN is bombesin) peptides and then labeled with (18)F via the 4-nitrophenyl-2-(18)F-fluoropropionate prosthetic group. Cytotoxicity and cell-binding assay of QD-RGD-BBN were performed with PC-3 cells. In vivo dual-modality PET/NIRF imaging of prostate tumor-bearing mice was investigated using QD-RGD-BBN and 2-(18)F-fluoropropionyl-QD-RGD-BBN ((18)F-FP-QD-RGD-BBN). An in vivo biodistribution study of (18)F-FP-QD-RGD-BBN was performed on normal mice.
  
  
  RESULTS
  QD-RGD-BBN exhibited strong red luminescence (600-800 nm) with the same maximum fluorescence wavelength (705 nm) as QD705 and slightly lower toxicity than that of QD705 in PC-3 cells at concentrations of greater than 30 μg/mL. Uptake of QD-RGD-BBN in PC-3 cells showed no significant decrease in the presence of an excess amount of dimer arginine-glycine-aspartate acid (RGD2) or bombesin(7-14) (BBN) peptide but was blocked significantly in the presence of an excess amount of NH2-RGD-BBN. Dual-function PET/NIRF imaging is able to accurately assess the biodistribution and tumor-targeting efficacy of the (18)F-labeled functionalized QDs.
  
  
  CONCLUSIONS
  The functionalized QD probe has great potential as a universal dual-targeting probe for detecting tumors in living subjects, opening up a new strategy for the development of multitargeting multimodality (18)F-labeled QD probes with improved tumor-targeting efficacy.
authors.affiliation: PET-CT Center, Department of Nuclear Medicine, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China; and.
authors.forename: Kongzhen
authors.initials: K
authors.lastname: Hu
authors.affiliation: PET-CT Center, Department of Nuclear Medicine, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China; and.
authors.forename: Hongliang
authors.initials: H
authors.lastname: Wang
authors.affiliation: PET-CT Center, Department of Nuclear Medicine, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China; and gtang0224@126.com niedahong@126.com.
authors.forename: Ganghua
authors.initials: G
authors.lastname: Tang
authors.affiliation: PET-CT Center, Department of Nuclear Medicine, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China; and.
authors.forename: Tingting
authors.initials: T
authors.lastname: Huang
authors.affiliation: College of Science, Southern China Agricultural University, Guangzhou, China gtang0224@126.com niedahong@126.com.
authors.forename: Xiaolan
authors.initials: X
authors.lastname: Tang
authors.affiliation: PET-CT Center, Department of Nuclear Medicine, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China; and.
authors.forename: Xiang
authors.initials: X
authors.lastname: Liang
authors.affiliation: PET-CT Center, Department of Nuclear Medicine, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China; and.
authors.forename: Shaobo
authors.initials: S
authors.lastname: Yao
authors.affiliation: PET-CT Center, Department of Nuclear Medicine, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China; and gtang0224@126.com niedahong@126.com.
authors.forename: Dahong
authors.initials: D
authors.lastname: Nie
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D001839:Bombesin / Q000493:pharmacokinetics; D003301:Copper Radioisotopes; D005260:Female; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D009369:Neoplasms / Q000000981:diagnostic imaging*; D009596:Nitrophenols / Q000737:chemistry; D009842:Oligopeptides / Q000737:chemistry; D010455:Peptides / Q000737:chemistry; D049268:Positron-Emission Tomography; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging; D045663:Quantum Dots; D018004:Receptors, Bombesin / Q000378:metabolism; D012666:Semiconductors; D013050:Spectrometry, Fluorescence; D014018:Tissue Distribution
chemical_list: D001672:Biocompatible Materials; D003301:Copper Radioisotopes; D009596:Nitrophenols; D009842:Oligopeptides; D010455:Peptides; D018004:Receptors, Bombesin; C024719:4-nitrophenyl; C047981:arginyl-glycyl-aspartic acid; D001839:Bombesin
keywords: GRPR; PET; fluorescence; integrin αvβ3; quantum dots