title: Positron emission tomography of human hepatocellular carcinoma xenografts in mice using copper (II)-64 chloride as a tracer with copper (II)-64 chloride.
abstract: OBJECTIVE
  The aim of this study was to assess copper metabolism of human hepatocellular carcinoma (HCC) with positron emission tomographic (PET) imaging using copper (II)-64 chloride ((64)CuCl(2)) as a tracer.
  
  
  METHODS
  PET imaging of athymic mice (n = 5) bearing extrahepatic HCC xenografts was performed 24 hours after the intravenous injection of (64)CuCl(2), followed by ex vivo tissue radioactivity assay. Expression of human copper transporter 1 (hCTR1) in HCC cells and tissues was examined by real-time reverse transcription polymerase chain reaction and immunohistochemistry analysis, respectively.
  
  
  RESULTS
  The extrahepatic HCC xenografts in mice with increased uptake of (64)Cu radionuclide were visualized on the micro-PET images obtained 24 hours after the intravenous injection of (64)CuCl(2). PET quantitative analysis revealed increased (64)Cu radioactivity in tumor tissues (2.7 ± 0.6 %ID/g) compared to that in the soft tissue of the left shoulder opposite to the tumor site (0.6 ± 0.2 %ID/g) and the brain (0.7 ± 0.1 %ID/g) but lower than that of the liver (16.6 ± 1.3 %ID/g). Expression of hCTR1 in the HCC cells and xenograft tumor tissues was demonstrated by real-time reverse transcription polymerase chain reaction and immunohistochemistry analysis, respectively. The expression level of hCTR1 in the Hep3B HCC xenograft tissues was lower than that detected in the normal hepatic tissues and the tissue samples of well-differentiated primary HCC. Variable expression of hCTR1 was detected in the tissue samples of moderately differentiated primary HCC.
  
  
  CONCLUSIONS
  Extrahepatic human HCC xenografts in mice could be localized with (64)CuCl(2) PET imaging, which might be useful for the localization and quantitative assessment of copper metabolism in extrahepatic metastases of HCC in humans.
authors: Carman & Ann Adams Department of Pediatrics, Wayne State University School of Medicine, Detroit, MI, USA.
authors: Haiyuan
authors: H
authors: Zhang
authors: Huawei
authors: H
authors: Cai
authors: Xin
authors: X
authors: Lu
authors: Otto
authors: O
authors: Muzik
authors: Fangyu
authors: F
authors: Peng
mesh_terms: D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging* / Q000378:metabolism*; D003300:Copper / Q000378:metabolism*; D003301:Copper Radioisotopes; D007150:Immunohistochemistry; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism*; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D049268:Positron-Emission Tomography; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014183:Transplantation, Heterologous
chemical_list: D003301:Copper Radioisotopes; D003300:Copper; C028419:cuprous chloride