title: Optimization of Early Response Monitoring and Prediction of Cancer Antiangiogenesis Therapy via Noninvasive PET Molecular Imaging Strategies of Multifactorial Bioparameters.
abstract: Objective: Antiangiogenesis therapy (AAT) has provided substantial benefits regarding improved outcomes and survival for suitable patients in clinical settings. Therefore, the early definition of therapeutic effects is urgently needed to guide cancer AAT. We aimed to optimize the early response monitoring and prediction of AAT efficacy, as indicated by the multi-targeted anti-angiogenic drug sunitinib in U87MG tumors, using noninvasive positron emission computed tomography (PET) molecular imaging strategies of multifactorial bioparameters.Methods:U87MG tumor mice were treated via intragastric injections of sunitinib (80 mg/kg) or vehicle for 7 consecutive days. Longitudinal MicroPET/CT scans with18F-FDG,18F-FMISO,18F-ML-10 and18F-Alfatide II were acquired to quantitatively measure metabolism, hypoxia, apoptosis and angiogenesis on days 0, 1, 3, 7 and 13 following therapy initiation. Tumor tissues from a dedicated group of mice were collected for immunohistochemical (IHC) analysis of key biomarkers (Glut-1, CA-IX, TUNEL, ανβ3and CD31) at the time points of PET imaging. The tumor sizes and mouse weights were measured throughout the study. The tumor uptake (ID%/gmax), the ratios of the tumor/muscle (T/M) for each probe, and the tumor growth ratios (TGR) were calculated and used for statistical analyses of the differences and correlations.Results:Sunitinib successfully inhibited U87MG tumor growth with significant differences in the tumor size from day 9 after sunitinib treatment compared with the control group (P < 0.01). The uptakes of18F-FMISO (reduced hypoxia),18F-ML-10 (increased apoptosis) and18F-Alfatide II (decreased angiogenesis) in the tumor lesions significantly changed during the early stage (days 1 to 3) of sunitinib treatment; however, the uptake of18F-FDG (increased glucose metabolism) was significantly different during the late stage. The PET imaging data of each probe were all confirmed via ex vivo IHC of the relevant biomarkers. Notably, the PET imaging of18F-Alfatide II and18F-FMISO was significantly correlated (all P < 0.05) with TGR, whereas the imaging of18F-FDG and18F-ML-10 was not significantly correlated with TGR.Conclusion: Based on the tumor uptake of the PET probes and their correlations with MVD and TGR,18F-Alfatide II PET may not only monitor the early response but also precisely predict the therapeutic efficacy of the multi-targeted, anti-angiogenic drug sunitinib in U87MG tumors. In conclusion, it is feasible to optimize the early response monitoring and efficacy prediction of cancer AAT using noninvasive PET molecular imaging strategies of multifactorial bioparameters, such as angiogenesis imaging with18F-Alfatide II, which represents an RGD-based probe.
authors.affiliation: Department of Radiology, Shanghai Pulmonary Hospital, Tongji University School of Medicine, 507 Zhengmin Road, Shanghai 200433, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Bao
authors.affiliation: Department of Nuclear Medicine, Fudan University Shanghai Cancer Center.
authors.forename: Ming-Wei
authors.initials: MW
authors.lastname: Wang
authors.affiliation: Department of Nuclear Medicine, Fudan University Shanghai Cancer Center.
authors.forename: Jian-Min
authors.initials: JM
authors.lastname: Luo
authors.affiliation: Department of Nuclear Medicine, Fudan University Shanghai Cancer Center.
authors.forename: Si-Yang
authors.initials: SY
authors.lastname: Wang
authors.affiliation: Department of Nuclear Medicine, Fudan University Shanghai Cancer Center.
authors.forename: Yong-Ping
authors.initials: YP
authors.lastname: Zhang
authors.affiliation: Department of Nuclear Medicine, Fudan University Shanghai Cancer Center.
authors.forename: Ying-Jian
authors.initials: YJ
authors.lastname: Zhang
mesh_terms: D020533:Angiogenesis Inhibitors / Q000008:administration & dosage*; D000818:Animals; D004195:Disease Models, Animal; D016903:Drug Monitoring / Q000379:methods*; D005909:Glioblastoma / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology; D064593:Heterografts; D007211:Indoles / Q000008:administration & dosage*; D008137:Longitudinal Studies; D051379:Mice; D057054:Molecular Imaging / Q000379:methods*; D009389:Neovascularization, Pathologic / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology; D049268:Positron-Emission Tomography / Q000379:methods*; D011379:Prognosis; D011758:Pyrroles / Q000008:administration & dosage*; D000077210:Sunitinib
chemical_list: D020533:Angiogenesis Inhibitors; D007211:Indoles; D011758:Pyrroles; D000077210:Sunitinib
keywords:  18F-ML-10; 18F-Alfatide II; 18F-FDG; 18F-FMISO; Antiangiogenesis therapy; Molecular imaging probe; PET; Sunitinib.; Therapy response