Through this Notice of Funding Opportunity (NOFO), the National Cancer Institute (NCI) encourages applications promoting transformative discoveries in cancer biology and/or oncology through the use of nanotechnology. Proposed projects should address major barriers in cancer biology and/or oncology using nanotechnology and should emphasize mechanistic studies toward fundamental understanding of nanomaterial and/or nanodevice interactions with biological systems. These studies should be performed in context of research concerning the delivery of nanoparticles and/or nano-devices to desired and intended cancer targets in vivo and/or characterization of detection and diagnostic devices in vitro. IRCN awards are expected to produce fundamental knowledge to aid future and more informed development of nanotechnology-based cancer interventions. The clinical translation of these interventions is outside of the scope of this NOFO.