Definition

A radioconjugate comprised of the microRNA-10b (miR-10b)-inhibitor TTX-MC138, which consists of an anti-miR10b antagomir conjugated to ultrasmall iron oxide nanoparticles, chelated with 1,4,7-triazacyclononane,1-glutaric acid-4,7 acetic acid (NODAGA) and radiolabeled with the radiotracer copper Cu 64, that may be used as an imaging agent for miR-10b-overexpressing tumor cells upon positron emission tomography (PET)-magnetic resonance imaging (PET-MRI). Upon administration of copper Cu 64 NODAGA- TTX-MC138, the TTX-MC138 moiety targets and binds to miR-10b inside tumor cells. This allows for visualization of miR-10b-overexpressing tumor cells upon imaging with PET-MRI. miR-10b, a mRNA that is highly expressed in a variety of metastatic tumor cells, plays a key role in tumor cell migration, invasion and metastasis.