Porphyrin-Based Mesoporous Organosilica Nanoparticles for Two-Photon Rhabdomyosarcoma Targeting

Recently, we described porphyrin-based periodic mesoporous organosilica (PMO) nanoparticles synthesized from a large functional octatriethoxysilylated porphyrin precursor. The framework of the nanoparticles was formed by J-aggregates of porphyrins allowing two-photon excitation photodynamic therapy (TPE-PDT) and NIR imaging. In this study, we functionalized these PMO with polyethylene glycol (PEG) moieties and an analogue of mannose 6-phosphate functionalized on anomeric position (AMFA). These AMFA are known to efficiently target mannose 6-phosphate receptors (M6PR) which are over-expressed in various cancer cell lines (breast, prostate). Here we show that M6PR is also over-expressed in rhabdomyosarcoma (RMS) cell lines. We targeted this receptor with PMO-AMFA and efficiently performed TPE imaging and TPE-PDT of RMS cells. Furthermore the same treatment did not affect healthy myoblasts, which have a low expression of M6PR.