LDLR and colorectal carcinoma: While OxPt/SN38 maintained intratumoral drug concentrations above IC50 values for CT26 and MC38 murine CRC cells and for HT29, HCT116, and SW480 human CRC cells for 72 h (Tables S7 and S8, Supporting Information), OxPt/SN38 with LDLR blockade, like the free drugs, failed to maintain intratumoral drug concentrations above IC50 values beyond 24 h.