SPECT imaging evaluation of 111indium-chelated cetuximab for diagnosing EGFR-positive tumor in an HCT-15-induced colorectal xenograft.
J Chin Med Assoc
; 80(12): 766-773, 2017 Dec.
Article
em En
| MEDLINE
| ID: mdl-28969991
ABSTRACT
BACKGROUND:
Epidermal growth factor receptor (EGFR) overexpressed in colorectal cancer (CRC) is a tumor target for developing the anti-tumor theranostic agents. Cetuximab, an anti-EGFR monoclonal antibody against EGFR-positive tumors, inhibits cell proliferation and growth was labeled with radioactive 111indium (111In) in this study for diagnosing EGFR-positive CRC. The aim of this study was to evaluate the efficacy of noninvasive nuclear imaging agent 111In-cetuximab and investigate the biological distribution of 111In-cetuximab in the HCT-15-induced EGFR-positive CRC tumor xenografts.METHODS:
We conjugated cetuximab with an isotope chelator, diethylene triamine penta acetic acid (DTPA), and consequently labeled cetuximab-DTPA with 111In and measured the labeling efficacy by an instant thin layer chromatography (iTLC). Furthermore, the 111In-cetuximab was investigated and compared for imaging small (50 mm3) and large (250 mm3) tumor of CRC xenografts, respectively.RESULTS:
The conjugated ratio between cetuximab and DTPA was 16 measured by MALDI-TOF-MS. The better labeling concentration of cetuximab with 10 mCi of 111In was calculated and experimented as 48 µg, resulting in labeling efficacy >80% detected by iTLC. The results revealed that the 111In-cetuximab accumulated in the both sizes of tumors as a reliable noninvasive diagnostic agent, whereas the ratio of tumor to muscle in the large tumor was 7.5-fold. The biodistribution data indicated that the 111In-cetuximab bound to tumor specifically that was higher than that in other organs.CONCLUSION:
We suggested that the 111In-cetuximab was potential for early diagnosis and prognostic monitor of EGFR-positive CRC in further clinical practice.Palavras-chave
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Radioisótopos de Índio
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Neoplasias Colorretais
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Tomografia Computadorizada de Emissão de Fóton Único
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Receptores ErbB
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Cetuximab
Tipo de estudo:
Diagnostic_studies
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Prognostic_studies
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Screening_studies
Limite:
Animals
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Humans
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Male
Idioma:
En
Revista:
J Chin Med Assoc
Assunto da revista:
MEDICINA
Ano de publicação:
2017
Tipo de documento:
Article