ToxStrategies scientists Drs. Allison Franzen and Susan Borghoff are among the authors of a new paper in the journal Critical Reviews in Toxicology. The work identifies an adverse outcome pathway (AOP), for kidney tumors that occur specifically in male rats through a mode of action (MoA) that is not relevant to humans—inducing α2u-globulin nephropathy (α2u-N). The authors define both the molecular initiating event (MIE) and key events (KEs) that lead to the occurrence of kidney tumors in male rats following chronic exposure to chemicals that have been shown to operate through this a2u-N MoA. Based on the confidence in the data identified to support this AOP, it can be used for hazard identification with the development of assays for the MIE and selected KEs, thereby decreasing the use of animal testing for regulatory applications.