FAP and neoplasm: In contrast, the specific depletion of FAP-positive fibroblasts either with genetic approaches (Feig et al. 2013; Arnold et al. 2014; Kraman et al. 2010) and immunologic methods (Lee et al. 2005; Loeffler et al. 2006; Kakarla et al. 2013; Ostermann et al. 2008; Schuberth et al. 2013; Tran et al. 2013; Wang et al. 2014) resulted in an inhibition of tumor growth.