Anticalins directed against the fibronectin extra domain B as diagnostic tracers for glioblastomas

TY - JOUR

T1 - Anticalins directed against the fibronectin extra domain B as diagnostic tracers for glioblastomas

AU - Albrecht, Valerie

AU - Richter, Antonia

AU - Pfeiffer, Sarah

AU - Gebauer, Michaela

AU - Lindner, Simon

AU - Gieser, Eugenie

AU - Schüller, Ulrich

AU - Schichor, Christian

AU - Gildehaus, Franz Josef

AU - Bartenstein, Peter

AU - Tonn, Jörg-Christian

AU - Skerra, Arne

AU - Glass, Rainer

N1 - © 2015 UICC.

PY - 2016/3/1

Y1 - 2016/3/1

N2 - The standard of care for diagnosis and therapy monitoring of gliomas is magnetic resonance imaging (MRI), which however, provides only an indirect and incomplete representation of the tumor mass, offers limited information for patient stratification according to WHO-grades and may insufficiently indicate tumor relapse after antiangiogenic therapy. Anticalins are alternative binding proteins obtained via combinatorial protein design from the human lipocalin scaffold that offer novel diagnostic reagents for histology and imaging applications. Here, the Anticalins N7A, N7E and N9B, which possess exquisite specificity and affinity for oncofetal fibronectin carrying the extra domain B (ED-B), a well-known proangiogenic extracellular matrix protein, were applied for immunohistochemical studies. When investigating ED-B expression in biopsies from 41 patients with confirmed gliomas of WHO grades I to IV, or in non-neoplastic brain samples, we found that Anticalins specifically detect ED-B in primary glioblastoma multiforme (GBM; WHO IV) but not in tumors of lower histopathological grade or in tumor-free brain. In primary GBM samples, ED-B specific Anticalins locate to fibronectin-rich perivascular areas that are associated with angiogenesis. Anticalins specifically detect ED-B both in fixed tumor specimen and on vital cells, as evidenced by cytofluorometry. Beyond that, we labeled an Anticalin with the γ-emitter (123) I and demonstrated specific binding to GBM-tissue samples using in vitro autoradiography. Overall, our data indicate that ED-B specific Anticalins are useful tools for the diagnosis of primary GBM and related angiogenic sites, presenting them as promising tracers for molecular tumor imaging.

AB - The standard of care for diagnosis and therapy monitoring of gliomas is magnetic resonance imaging (MRI), which however, provides only an indirect and incomplete representation of the tumor mass, offers limited information for patient stratification according to WHO-grades and may insufficiently indicate tumor relapse after antiangiogenic therapy. Anticalins are alternative binding proteins obtained via combinatorial protein design from the human lipocalin scaffold that offer novel diagnostic reagents for histology and imaging applications. Here, the Anticalins N7A, N7E and N9B, which possess exquisite specificity and affinity for oncofetal fibronectin carrying the extra domain B (ED-B), a well-known proangiogenic extracellular matrix protein, were applied for immunohistochemical studies. When investigating ED-B expression in biopsies from 41 patients with confirmed gliomas of WHO grades I to IV, or in non-neoplastic brain samples, we found that Anticalins specifically detect ED-B in primary glioblastoma multiforme (GBM; WHO IV) but not in tumors of lower histopathological grade or in tumor-free brain. In primary GBM samples, ED-B specific Anticalins locate to fibronectin-rich perivascular areas that are associated with angiogenesis. Anticalins specifically detect ED-B both in fixed tumor specimen and on vital cells, as evidenced by cytofluorometry. Beyond that, we labeled an Anticalin with the γ-emitter (123) I and demonstrated specific binding to GBM-tissue samples using in vitro autoradiography. Overall, our data indicate that ED-B specific Anticalins are useful tools for the diagnosis of primary GBM and related angiogenic sites, presenting them as promising tracers for molecular tumor imaging.

KW - Antibodies

KW - Antigens, CD31

KW - Brain Neoplasms

KW - Cell Line, Tumor

KW - Fibronectins

KW - Glioblastoma

KW - Humans

KW - Immunohistochemistry

KW - Lipocalins

KW - Molecular Imaging

KW - Peptide Library

KW - Protein Binding

KW - Protein Structure, Tertiary

KW - Journal Article

KW - Research Support, Non-U.S. Gov't

U2 - 10.1002/ijc.29874

DO - 10.1002/ijc.29874

M3 - SCORING: Journal article

C2 - 26421425

VL - 138

SP - 1269

EP - 1280

JO - INT J CANCER

JF - INT J CANCER

SN - 0020-7136

IS - 5

ER -