title: In vivo photoacoustic tomography of EGFR overexpressed in hepatocellular carcinoma mouse xenograft.
abstract: EGFR is a promising cell surface target for in vivo imaging that is highly overexpressed in hepatocellular carcinoma (HCC), a common cancer worldwide. Peptides penetrate easily into tumors for deep imaging, and clear rapidly from the circulation to minimize background. We aim to demonstrate use of an EGFR specific peptide to detect HCC xenograft tumors in mice with photoacoustic imaging. Nude mice implanted with human HCC cells that overexpress EGFR were injected intravenously with Cy5.5-labeled EGFR and scrambled control peptides respectively. Photoacoustic images collected from 0 to 24 h. Photoacoustic signal peaked in tumors at 3 h post-injection. Images from 0 to 1.8 cm beneath the skin revealed increased target-to-background (T/B) ratio from tumors. The T/B ratio was significantly greater for the EGFR versus control peptide. Clearance of signal was observed by ∼24 h. EGFR overexpression was validated with immunofluorescence and immunohistochemistry. A peptide specific for EGFR delivered systemically can detect HCC xenograft tumors in vivo with photoacoustic imaging.
authors.affiliation: Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, United States.
authors.forename: Quan
authors.initials: Q
authors.lastname: Zhou
authors.affiliation: Department of Hepatobiliary Surgery, Peking University People's Hospital, Beijing, China.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Medicine, Division of Gastroenterology, University of Michigan, Ann Arbor, MI 48109, United States.
authors.forename: Juan
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Department of Medicine, Division of Gastroenterology, University of Michigan, Ann Arbor, MI 48109, United States.
authors.forename: Bishnu P
authors.initials: BP
authors.lastname: Joshi
authors.affiliation: Department of Medicine, Division of Gastroenterology, University of Michigan, Ann Arbor, MI 48109, United States.
authors.forename: Gaoming
authors.initials: G
authors.lastname: Li
authors.affiliation: Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, United States.
authors.forename: Xiyu
authors.initials: X
authors.lastname: Duan
authors.affiliation: Department of Biostatistics, University of Michigan, Ann Arbor, MI 48109, United States.
authors.forename: Rork
authors.initials: R
authors.lastname: Kuick
authors.affiliation: Department of Pathology, University of Michigan, Ann Arbor, MI 48109, United States.
authors.forename: Scott R
authors.initials: SR
authors.lastname: Owens
authors.affiliation: Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, United States; Department of Medicine, Division of Gastroenterology, University of Michigan, Ann Arbor, MI 48109, United States; Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, United States.
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Wang
keywords: AU, arbitrary units; EGFR, epidermal growth factor receptor; Epidermal growth factor receptor (EGFR); HCC, hepatocellular carcinoma; Hepatocellular carcinoma; Imaging; PA, photoacoustic; Peptide; Photoacoustic; T/B, target-to-background