PDGFRB and neoplasm: Owing to the high expression of PDGFRβ in tumor-associated pericytes (Paulsson et al., 2009) and the high affinity and specificity of ZPDGFRβ affibody for PDGFRβ (Lindborg et al., 2011; Tao et al., 2017), pericyte-targeted delivery can be achieved by the conjugation of PS to the ZPDGFRβ affibody.