SPARC and Patent ductus arteriosus: On this basis, a novel drug formulation consisting of paclitaxel associated with albumin (Abraxane or nab-paclitaxel) has been hypothesized to accumulate in and potentially deplete PDA tumor stroma via binding of albumin to SPARC-positive fibroblasts, thus representing a mechanism for targeting a specific cell type within the PDA tumor microenvironment [188].