In Vitro Radiosensitization Of Human Neuroblastoma Cells With Iron Oxide - Titanium Dioxide Core-Shell Nanocomposites Conjugated With 3,4-Dihydroxyphenylacetic Acid (Dopac)

Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Radiation therapy plays an important role in controlling tumor growth in cancers, including neuroblastoma, one of the most frequent extra cranial solid tumors in children. However, tumor radioresistance remains to be a major obstacle in clinical radiotherapy. In this study, we explored titanium dioxide core-shell nanocomposites conjugated with DOPAC (DOPAC-NCs) as radiosensitizers. Human neuroblastoma SK-N-AS and SK-N-DZ cell cultures were treated with or without of increasing concentrations of DOPAC-NCs (200-3000 nM) prior to irradiation. One hour later, cells were irradiated with a single dose of gamma radiation (0 - 10 Gy). Seventy-two hours following radiation treatment, cell proliferation/viability was assessed by MTS assay. Sham-irradiated cells served as a control. We have found that treatment of SK-N-AS and SK-N-DZ cells with DOPAC-NCs affected cell survival in a dose-dependent manner. Our data also demonstrated the evidence of DOPAC-NCs radiosensitization to gamma radiation. For examples, cell survival of SK-N-AS cells irradiated with 5 Gy and pre-treated with 1000 nM of DOPAC-NCs was as low as 35.6%. Oppositely, without radiation, treatment with the same concentration of DOPAC-NCs had no effect on cell viability. These findings provide in vitro evidence that DOPAC-NCs may be developed and employed as radiosensitizers in neuroblastoma radiation therapy. Citation Format: Salida Mirzoeva, William Liu, James R. Bolling, Karna R. Shah, Carol Hirschmugl, Julia Sedlmair, Tatjana Paunesku, Gayle E. Woloschak. In vitro radiosensitization of human neuroblastoma cells with iron oxide - titanium dioxide core-shell nanocomposites conjugated with 3,4-Dihydroxyphenylacetic acid (DOPAC). [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4918. doi:10.1158/1538-7445.AM2014-4918