journal contribution
posted on 2023-03-31, 17:34 authored by Libo Zhang, Paula Marrano, Sushil Kumar, Michael Leadley, Evelyn Elias, Paul Thorner, Sylvain Baruchel <p>PDF file - 229K, Supplementary Figure 1. Expression of SPARC and PTEN in neuroblastoma cell lines. SPARC and PTEN expression were assessed in a panel of eight neuroblastoma cell lines by Western Blot. For Western blot analysis, 50 microg protein was resolved over 10% polyacrylamide gels and transferred to a nitrocellulose membrane. The blot was blocked in blocking buffer (5% non-fat dry milk/1� Tween 20 in TBS) for 1 h at room temperature, incubated with polyclonal primary antibodies against SPARC (Cell Signaling Technology) and PTEN (Cell Signaling Technology) overnight at 4 {degree}C. The blot was then incubated with appropriate horseradish peroxidase conjugated secondary antibody and detected by enhanced chemiluminescence and autoradiography using X-ray film. beta-actin was detected on the same membrane and used as a loading control</p>
History
ARTICLE ABSTRACT
Purpose: To investigate the antitumor effect of nab-paclitaxel, an albumin-stabilized nanoparticle formulation of paclitaxel, on pediatric solid tumor models.Experimental Design: A panel of three rhabdomyosarcoma, one osteosarcoma and seven neuroblastoma cell lines were exposed to increasing concentrations of nab-paclitaxel in vitro. Cell viability was evaluated using the Alamar Blue Assay. Antitumor effect was further assessed in vivo in NOD/SCID xenograft and metastatic neuroblastoma mouse models. Tumor sections were analyzed by immunohistochemistry for cleaved caspase-3 and phospho-histone H3. Plasma and intratumoral paclitaxel concentrations were measured by liquid chromatography–mass spectrometry. Ratio of intratumoral and plasma concentration was compared between nab-paclitaxel and paclitaxel treatment groups.Results: Nab-paclitaxel displayed significant cytotoxicity against most pediatric solid tumor cell lines in vitro in a dose-dependent manner. In vivo, nab-paclitaxel showed antitumor activity in both rhabdomyosarcoma (RH4 and RD) and neuroblastoma [SK-N-BE(2) and CHLA-20] xenograft models. In the SK-N-BE(2) metastatic model, nab-paclitaxel treatment significantly extended animal survival compared with control (P < 0.01). Nab-paclitaxel treatment induced tumor cell-cycle arrest and apoptosis in vivo. In the RH4 model, increased local relapse-free intervals were observed with nab-paclitaxel treatment (37.7 ± 3.2 days) comparing with paclitaxel (13.6 ± 2.07 days). Local relapsed tumors following paclitaxel treatment proved to be paclitaxel-resistant and remained responsive to nab-paclitaxel. Mechanistically, a higher tumor/plasma paclitaxel drug ratio in favor of nab-paclitaxel was observed.Conclusions: Nab-paclitaxel showed significant antitumor activity against all pediatric solid tumors associated with an enhanced drug intratumor delivery. Furthermore, testing of nab-paclitaxel in pediatric solid-tumor patient population is under development. Clin Cancer Res; 19(21); 5972–83. ©2013 AACR.
