NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.

Molecular Imaging and Contrast Agent Database (MICAD) [Internet]. Bethesda (MD): National Center for Biotechnology Information (US); 2004-2013.

Cover of Molecular Imaging and Contrast Agent Database (MICAD)

Molecular Imaging and Contrast Agent Database (MICAD) [Internet].

Show details

89Zr-Desferrioxamine-anti-epithelial glycoprotein-1 hRS7 humanized monoclonal antibody

, PhD
National for Biotechnology Information, NLM, NIH, Bethesda, MD

Created: ; Last Update: April 19, 2012.

Chemical name:89Zr-Desferrioxamine-anti-epithelial glycoprotein-1 hRS7 humanized monoclonal antibody
Abbreviated name:89Zr-Df-hRS1
Agent category:Antibody
Target:Epithelial glycoprotein-1 (EGP-1, also known as TROP2)
Target category:Receptor
Method of detection:Positron emission tomography (PET)
Source of signal/ contrast:89Zr
  • Checkbox In vitro
  • Checkbox Rodents
Click on protein, nucleotide (RefSeq), and gene for more information about EGP-1



Epithelial glycoprotein-1 (EGP-1, also known as TROP2) is a transmembrane glycoprotein (46 kDa) identified with murine IgG1 monoclonal antibody (mAb) RS7 raised against human non-small cell lung carcinoma (1). EGP-1 is also present in human carcinomas of the stomach, bladder, breast, ovary, uterus, and prostate, but it is not expressed in most normal tissues. EGP-1 is expressed at low levels in glandular cells in the bronchus, breast, prostate, skin, and pancreas. EGP-1 activates intracellular calcium mobilization (2) and protein kinase C (3) after binding with RS7. EGP-1 is a cell-surface receptor with unknown physiological ligand and cellular functions. However, EGP-1 has been implicated in the activation of the ERK/MAPK pathway, leading to downstream alterations in cellular proliferation, migration, invasion, and survival of cancer cells (4). EGP-1 overexpression has been associated with increased tumor invasiveness and decreased overall survival rates in multiple types of human carcinomas (5, 6). van Rij et al. (7) evaluated 89Zr-desferrioxamine-hRS7 (89Zr-Df-hRS7) as a 89Zr-based positron emission tomography (PET) agent in human prostate PC-3 tumors in nude mice.



Df-hRS7 was prepared by conjugation of N-succinyldesferrioxamine tetrafluorophenol to hRS7 for 30 min at 25°C. Df-hRS7 was purified with column chromatography (7). There was one Df moiety per mAb. Df-hRS7 was incubated with 89Zr-oxalate in HEPES buffer (pH 7) for 90 min at 25°C. 89Zr-Df-hRS7 was purified with column chromatography. This procedure provided a radiolabeling yield of 60%, with a specific activity of 82 MBq/nmol (2.2 mCi/nmol) and a radiochemical purity of >95%.

In Vitro Studies: Testing in Cells and Tissues


Immunostaining of PC-3 tumor sections with hRS7 showed the expression of EGP-1 in the membranes and cytosol of PC-3 tumor cells (7). Immunochemical analysis of three human primary prostate tumor sections showed high homogeneous and consistent expression of EGP-1 in all three tumors and metastases in a lymph node and in the liver. The immunoreactivity of 89Zr-Df-hRS7 was >80%.

Animal Studies



van Rij et al. (7) injected 11 MBq (0.3 mCi (0.13 nmol)) 89Zr-Df-hRS7 into male nude mice (n = 5) bearing the EGP-1–positive PC-3 prostate tumors for PET imaging at 1, 3, and 7 d. PET imaging estimated tumor accumulation of 31%, 46%, and 55% injected dose/gram (ID/g) at 1, 3, and 7 d after injection of 89Zr-Df-hRS7, respectively. The radioactivity in the blood was 16% ID/g at 1 d and declined to 6% ID/g at 7 d. The tumors were clearly visualized at 3 d and 7 d. There was little accumulation in the other organs except the femur (~3% ID/g at 3 d and ~10% ID/g at 7 d). The tumor/liver ratios were 2.9, 6.5, and 7.7 at 1, 3, and 7 d, respectively. Co-injection of excess hRS7 (3.3 nmol) inhibited accumulation in the tumors to 10% ID/g at 3 d after injection. Little inhibition was observed in the other organs, including the femur. The imaging studies were not confirmed by ex vivo biodistribution.

Other Non-Primate Mammals


No publication is currently available.

Non-Human Primates


No publication is currently available.

Human Studies


No publication is currently available.


Stein R., Chen S., Sharkey R.M., Goldenberg D.M. Murine monoclonal antibodies raised against human non-small cell carcinoma of the lung: specificity and tumor targeting. Cancer Res. 1990;50(4):1330–6. [PubMed: 2153458]
Ripani E., Sacchetti A., Corda D., Alberti S. Human Trop-2 is a tumor-associated calcium signal transducer. Int J Cancer. 1998;76(5):671–6. [PubMed: 9610724]
Basu A., Goldenberg D.M., Stein R. The epithelial/carcinoma antigen EGP-1, recognized by monoclonal antibody RS7-3G11, is phosphorylated on serine 303. Int J Cancer. 1995;62(4):472–9. [PubMed: 7635574]
Cubas R., Zhang S., Li M., Chen C., Yao Q. Trop2 expression contributes to tumor pathogenesis by activating the ERK MAPK pathway. Mol Cancer. 2010;9:253. [PMC free article: PMC2946292] [PubMed: 20858281]
Varughese J., Cocco E., Bellone S., de Leon M., Bellone M., Todeschini P., Schwartz P.E., Rutherford T.J., Pecorelli S., Santin A.D. Uterine serous papillary carcinomas overexpress human trophoblast-cell-surface marker (Trop-2) and are highly sensitive to immunotherapy with hRS7, a humanized anti-Trop-2 monoclonal antibody. Cancer. 2011;117(14):3163–72. [PMC free article: PMC3128671] [PubMed: 21246534]
Bignotti E., Todeschini P., Calza S., Falchetti M., Ravanini M., Tassi R.A., Ravaggi A., Bandiera E., Romani C., Zanotti L., Tognon G., Odicino F.E., Facchetti F., Pecorelli S., Santin A.D. Trop-2 overexpression as an independent marker for poor overall survival in ovarian carcinoma patients. Eur J Cancer. 2010;46(5):944–53. [PubMed: 20060709]
van Rij C.M., Sharkey R.M., Goldenberg D.M., Frielink C., Molkenboer J.D., Franssen G.M., van Weerden W.M., Oyen W.J., Boerman O.C. Imaging of prostate cancer with immuno-PET and immuno-SPECT using a radiolabeled anti-EGP-1 monoclonal antibody. J Nucl Med. 2011;52(10):1601–7. [PubMed: 21865288]


  • PubReader
  • Print View
  • Cite this Page
  • PDF version of this page (581K)
  • MICAD Summary (CSV file)

Search MICAD

Limit my Search:

Related information

  • PMC
    PubMed Central citations
  • PubMed
    Links to PubMed

Similar articles in PubMed

See reviews...See all...

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...