title: Biodistribution and imaging of [99mTc]-HYNIC-RGD in MDA-MB-231 and NTERA-2 cancer cell xenografts.
abstract: OBJECTIVE
  Increased expression of αvβ3 integrins is involved in tumour angiogenesis. Targeting these receptors with a dedicated peptide containing the RGD sequence may provide information about the receptor status in and around the tumour and about the angiogenesis process involved. The aim of this study was to compare the uptake of [Tc]-HYNIC-RGD in two types of tumours that either express or do not express the αvβ3 receptor (NTERA-2 and MDA-MB-231, respectively) and discuss the use of this tracer in experimental models of angiogenesis.
  
  
  METHODS
  Uptake of intravenously injected [Tc]-HYNIC-RGD was studied ex vivo and in vivo. Histological analysis of excised tumours was carried out. Percentages of the injected dose uptake per gram of tissue were compared between the two types of tumours and in the periphery and centre of each tumour.
  
  
  RESULTS
  [Tc]-HYNIC-RGD was rapidly cleared from blood circulation and excreted through the kidneys. Residual activity was retained in the intestine. Tumour uptake of [Tc]-HYNIC-RGD was high and homogeneous for αvβ3-positive cell lines (1.94±0.26%ID/g). Tumour uptake was weak and distributed only in the tumour periphery for αvβ3-negative cell lines (0.10±0.02%ID/g, tumour periphery; 0.06±0.01%ID/g, tumour core; P=0.01). These results correlated with vessel distribution.
  
  
  CONCLUSIONS
  Uptake of [Tc]-HYNIC-RGD was more intense in αvβ3-positive cell lines than in αvβ3-negative cell lines, but tracer distribution was more representative of angiogenic locations in αvβ3-negative cell lines. Further clinical and preclinical studies are needed on the use of RGD-related tracers.
authors: Department of Nuclear Medicine, Henri Becquerel Centre and QuantIF-LITIS EA4108, University of Rouen, Cedex, France. pierre.bohn@chb.unicancer.fr
authors: Pierre
authors: P
authors: Bohn
authors: Romain
authors: R
authors: Modzelewski
authors: Jean
authors: J
authors: Rouvet
authors: Mélanie
authors: M
authors: Briand
authors: Soizic
authors: S
authors: Dutoit
authors: Jean-Yves
authors: JY
authors: Pille
authors: Jean-Michel
authors: JM
authors: Picquenot
authors: Nicolas
authors: N
authors: Aide
authors: Pierre
authors: P
authors: Vera
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D002471:Cell Transformation, Neoplastic; D003952:Diagnostic Imaging / Q000379:methods*; D006801:Humans; D015609:Organotechnetium Compounds / Q000737:chemistry / Q000493:pharmacokinetics*; D010456:Peptides, Cyclic / Q000737:chemistry / Q000493:pharmacokinetics*; D011854:Radiochemistry; D051381:Rats; D011923:Rats, Nude; D013724:Teratoma / Q000000981:diagnostic imaging / Q000473:pathology; D014018:Tissue Distribution; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed
chemical_list: D015609:Organotechnetium Compounds; D010456:Peptides, Cyclic; C585528:technetium 99m HYNIC-RGD