216
imaging method for personalized cancer treatment by identifying and monitoring
patients who have increased tumor tryptophan metabolism and are potentially sensi-
tive to immunopharmacotherapy with indoleamine 2,3-dioxygenase inhibitors
(Juhász et al. 2009 ).
Image-Guided Personalized Drug Delivery in Cancer
Image-guided drug delivery (IGDD) in cancer is a form of individualized therapy
where imaging methods are used in guidance and monitoring of localized and tar-
geted delivery of therapeutics to the tumor. A systematic approach to IGDD requires
mechanisms for targeting, delivery, activation, and monitoring of the process.
Although the goal in IGDD is to optimize the therapeutic ratio through personalized
image-guided treatments, a major challenge is in overcoming the biological barriers
to the delivery of therapeutics into tumors and cells. Physiologic and quantitative
imaging techniques may serve as enabling tools that could potentially transform
many existing challenges into opportunities for advancement of the fi eld (Tandon
and Farahani 2011 ).
Tumor Imaging and Elimination by Targeted Gallium Corrole
Sulfonated gallium(III) corroles are intensely fl uorescent macrocyclic compounds
that spontaneously assemble with carrier proteins to undergo cell entry. In vivo
imaging and therapeutic effi cacy of a tumor-targeted corrole noncovalently assem-
bled with a heregulin-modifi ed protein directed at the human EGFR. Systemic
delivery of this protein-corrole complex results in tumor accumulation, which can
be visualized in vivo owing to intensely red corrole fl uorescence. Targeted delivery
in vivo leads to tumor cell death while normal tissue is spared in contrast with the
effects of doxorubicin, which can elicit cardiac damage during therapy and required
direct intratumoral injection to yield similar levels of tumor shrinkage compared
with the systemically delivered corrole (Agadjanian et al. 2009 ). The targeted com-
plex ablated tumors at >5 times a lower dose than untargeted systemic doxorubicin,
and the corrole does not damage heart tissue. Complexes remain intact in serum and
the carrier protein elicits no detectable immunogenicity. The sulfonated gallium(III)
corrole functions both for tumor detection and intervention with safety and targeting
advantages over standard chemotherapy.
Future Prospects of Molecular Imaging in Management of Cancer
Molecular imaging can improve therapeutic strategies that provide better patient
selection for therapeutic personalization than conventional methods and provides a
variety of new tools to accelerate the development of cancer therapies. The recent
drive to develop molecular imaging probes and standardize molecular imaging
10 Personalized Therapy of Cancer