Molecular Mechanism of Local Drug Delivery with Paclitaxel-Eluting Membranes in Biliary and Pancreatic Cancer: New Application for an Old Drug

Figure 2

Paclitaxel-eluting membrane (PEM) implantation inhibits mTORC1 activation and hypoxia-inducible factor (HIF)-1 regulation in xenografted tumors. (a) Western blotting of phospho-S6K, S6K, phospho-S6, S6, phospho-4EBP1, and 4EBP1 expression levels in tumor lysates from HuCCT-1 tumors implanted with the PEM or control (+Plu) (left). Relative quantification of phosphoprotein expression levels is shown in the control (gray bars) or PEM (black bars) implanted tumors. Values are corrected for corresponding total antibody protein ; (right). (b) Western blotting of phospho-S6K and S6K expression levels in tumor lysates from indicated tumors from the PEM-implanted or control groups (left) and relative quantification of phospho-S6K expression levels (right). (c) Western blot of HIF-1α and HIF-1β in a protein extract from indicated tumors implanted with the PEM or control for 20 days (left). SCK xenograft tumors were treated with 0, 5, and 10% PEM and implanted for 7 days. Tumor protein lysates were prepared and analyzed for Raptor and HIF-1α protein expression. Immunoprecipitation and Western blotting were used to detect the endogenous Raptor-HIF-1α interaction (right). (d) Western blotting analysis of cyclin B1 expression levels in tumor lysates from indicated tumors treated with various concentrations of PEM (SCK, 0, 5, and 10%; CFPAC-1, 0, 1, and 5%).

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