Osteotropic cancer diagnosis by an osteocalcin inspired molecular imaging mimetic.

Abstract

BACKGROUND:

Although microcalcifications of hydroxyapatite can be found in both benign and malignant osteotropic tumors, they are mostly seen in proliferative lesions, including carcinoma. The aim of this present study is to develop a molecular imaging contrast agent for selective identification of hydroxyapatite calcification in human osteotropic tumor tissues ex vivo and in human osteosarcoma cells in vitro.

METHODS:

A bioinspired biomarker, hydroxyapatite binding peptide (HABP), was designed to mimic natural protein osteocalcin property in vivo. A fluorescein isothiocyanate dye conjugated HABP (HABP-19) was utilized to characterize hydroxyapatite on human osteotropic tumor tissue sections ex vivo and to selectively image hydroxyapatite calcifications in human osteosarcoma cells in vitro.

RESULTS:

Using a HABP-19 molecular imaging probe, we have shown that it is possible to selectively image hydroxyapatite calcifications in osteotropic cancers ex vivo and in human SaOS-2 osteosarcoma cells in vitro.

CONCLUSION:

Hydroxyapatite calcifications were selectively detected in osteotropic tissues ex vivo and in the early stage of the calcification process of SaOS-2 human osteosarcoma in vitro using our HABP-19 molecular imaging probe. This new target-selective molecular imaging probe makes it possible to study the earliest events associated with hydroxyapatite deposition in various osteotropic cancers at the cellular and molecular levels.

GENERAL SIGNIFICANCE:

It potentially could be used to diagnose and treat osteotropic cancer or to anchor therapeutic agents directing the local distribution of desired therapy at calcified sites.

• Authors: Jae Sam Lee, Ching-Hsuan Tung
• Journal: Biochimica et biophysica acta (Biochim Biophys Acta) Vol. 1830 Issue 10 Pg. 4621-7 (Oct 2013) ISSN: 0006-3002 [Print] Netherlands
• PMID: 23688398 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)
• Copyright: Copyright © 2013 Elsevier B.V. All rights reserved.

Chemical References

• Osteocalcin
• Durapatite
• Fluorescein-5-isothiocyanate

Topics

• Bone Neoplasms (diagnosis, metabolism)
• Cell Line, Tumor
• Durapatite (metabolism)
• Fluorescein-5-isothiocyanate
• Humans
• Molecular Mimicry
• Osteocalcin (metabolism)
• Osteosarcoma (diagnosis, metabolism)
• Tissue Array Analysis