Title:In Vivo Imaging of Apoptosis in Cancer: Potentials and Drawbacks of Molecular Probes
Volume: 1
Issue: 1
Author(s): Soyoun Kim, Kiweon Cha and In-San Kim
Affiliation:
Keywords:
Apoptosis, molecular imaging of cancer therapy, phosphatidylserine, caspase-3, Annexin A5, PS indicator,
aposense family, ApoPep-1, histone H1, 18F-ML10.
Abstract: Molecular imaging of apoptosis can be applied for diagnosis and/or therapeutics in the field of oncology since
it may allow rapid assessment of cancer treatment. Various imaging techniques are employed to visualize apoptotic cells
in vivo to probe function of enzymatic and morphologic events occurring during cell death. In the present review, we outline
recent investigation of imaging molecules targeting early apoptotic processes, such as externalization of phosphatidylserine,
activation of caspases, and other apoptotic changes which can be de novo targets on the cell surface or inside of
the cells. Including Annexin-A5 derivatives, which are the most successful and widely applied approaches in apoptosis
imaging based on specific interaction with phophatidylserine, current researches of other phosphatidylserine indicators,
caspase substrates/inhibitors, and numerous de novo imaging molecules are discussed with points of potential advantages
and drawbacks. Two of them, 99mTc- or 123I-labeled annexin A5 and 18F-ML10, have progressed to clinical trials which
hold great promise for specific imaging of apoptosis in several types of cancer patients for early assessment of therapy.
Furthermore, new targets and accompanying new tracers such as histone H1 and ApoPep-1, respectively, and development
of translatable labeling platforms will lead to a rapid expansion of apoptosis imaging allowing fast assessment of
therapy efficacy in cancer.