Stroma targeting nuclear imaging and radiopharmaceuticals

License for destruction: tumor-specific cytokine targeting

Stroma is an integral part of solid tumors and plays a key role in growth promotion and immune suppression. Most current therapies focus on destroying tumors and/or abnormal vasculature. However, evidence is emerging that anticancer efficacy improves with vessel normalization rather than destruction. Specific targeting of cytokines into tumors provides proof-of-concept that tumor stroma is dynamic and can be remodeled to increase drug access and alleviate immune suppression. Changing the inflammatory milieu 'opens' tumors for therapy and thus provides a license for destruction. This involves reprogramming of paracrine signaling networks between multiple stromal components to break the vicious cycle of angiogenesis and immune suppression. With active immunotherapy rapidly moving into the clinic, local cytokine delivery emerges as an attractive adjuvant.

New frontiers in the design and synthesis of imaging probes for PET oncology: current challenges and future directions

Despite being developed over 30 years ago, 2-deoxy-2-[(18)F]fluoro-D-glucose remains the most frequently used radiotracer in PET oncology. In the last decade, interest in new and more specific radiotracers for imaging biological processes of oncologic interest has increased exponentially. This review summarizes the strategies underlying the development of those probes together with their validation and status of clinical translation; a brief summary of new radiochemistry strategies applicable to PET imaging is also included. The article finishes with a consideration of the challenges imaging scientists must overcome to bring about increased adoption of PET as a diagnostic or pharmacologic tool.