Targeting IGF-1R: at a crossroad.

In this issue of ONCOLOGY, Golan and Javle provide an excellent update on targeting the insulin growth factor (IGF-1R) in gastrointestinal cancers. The review opens with the statement “IGF-1–directed therapy is currently at a crossroads”; this truly sums up the current status of the field. Decades of laboratory and preclincial research have shown a role for IGF-1R in many cancers; however, this hypothesis is now being tested directly in clinical trials. The crossroads the authors refer to, which several other targeted therapies have previously arrived at, is a dangerous one. The requirement for rapid clinical development of therapeutics demanded by both the pharmaceutical industry and patient advocates results in the risk that several therapies will be abandoned simply because trials have been performed in unselected populations. In this commentary, we will not dwell on the large literature implicating IGF-IR in cancer, but rather focus on the road forward for development of IGF-1R inhibitors.