Medicine and Health Sciences Commons^™

Electrotransfer Of Plasmid Dna Radiosensitizes B16f10 Tumors Through Activation Of Immune Response, Richard Heller

Medical Diagnostics & Translational Sciences Faculty Publications

Background
Tumor irradiation combined with adjuvant treatments, either vascular targeted or immunomodulatory, is under intense investigation. Gene electrotransfer of therapeutic genes is one of these approaches. The aim of this study was to determine, whether gene electrotransfer of plasmid encoding shRNA for silencing endoglin, with vascular targeted effectiveness, can radiosensitize melanoma B16F10 tumors.

Materials and methods
The murine melanoma B16F10 tumors, growing on the back of C57Bl/6 mice, were treated by triple gene electrotransfer and irradiation. The antitumor effect was evaluated by determination of tumor growth delay and proportion of tumor free mice. Furthermore, histological analysis of tumors (necrosis, apoptosis, …

The Role Of Neighborhood Characteristics In Late Stage Melanoma Diagnosis Among Hispanic Men In California, Texas, And Florida, 1996-2012, Valerie M. Harvey, Clinton W. Enos, Jarvis T. Chen, Hadiza Galadima, Karl Eschbach

Community & Environmental Health Faculty Publications

Background. Hispanics diagnosed with cutaneous melanoma are more likely to present at advanced stages but the reasons for this are unknown. We identify census tracts at high risk for late stage melanoma diagnosis (LSMD) and examine the contextual predictors of LSMD in California, Texas, and Florida. Methods. We conducted a cross-sectional study using geocoded state cancer registry data. Using hierarchical multilevel logistic regression models we estimated ORs and 95% confidence intervals for the impact of socioeconomic, Hispanic ethnic concentration, index of dissimilarity, and health resource availability measures on LSMD. Results. We identified 12,493 cases. In California, late …

Facilitation Of Electroporative Drug Uptake And Cell Killing By Electrosensitization, Olga N. Pakhomova, Betsy W. Gregory, Andrei G. Pakhomov

Bioelectrics Publications

Cell permeabilization by electric pulses (EP), or electroporation, is widely used for intracellular delivery of drugs and plasmids, as well as for tumour and tissue ablation. We found that cells pre-treated with 100-mus EP develop delayed hypersensitivity to subsequent EP applications. Sensitizing B16 and CHO cells by splitting a single train of eight 100-mus EP into two trains of four EP each (with 5-min. interval) decreased the LD(50) 1.5-2 times. Sensitization profoundly enhanced the electroporation-assisted uptake of bleomycin, a cell-impermeable cytotoxic agent accepted for killing tumours by electrochemotherapy. EP exposures that were not lethal per se caused cell death in …

Comparative Study Of Long-And Short-Pulsed Electric Fields For Treating Melanoma In An In Vivo Mouse Model, Xinhua Chen, Xinmei Chen, Karl H. Schoenbach, Shusen Zheng, R. James Swanson

Bioelectrics Publications

A mouse melanoma model was set up with green fluorescent protein (GFP) expression in vivo. With the same energy, long- (1 ms) and short- (300 ns) pulsed electric fields were delivered to two melanomas injected into the same mouse. The tumor growth and green fluorescence were followed up to compare the different treatment efficacy of long and short pulses. After two days post treatment, short pulse-treated tumors showed a significantly lower tumor volume compared with long pulse-treated tumors (n=8, p

Bioelectric Applications For Treatment Of Melanoma, Stephen J. Beebe, Karl H. Schoenbach, Richard Heller

Bioelectrics Publications

Two new cancer therapies apply bioelectric principles. These methods target tumor structures locally and function by applying millisecond electric fields to deliver plasmid DNA encoding cytokines using electrogene transfer (EGT) or by applying rapid rise-time nanosecond pulsed electric fields (nsPEFs). EGT has been used to locally deliver cytokines such as IL-12 to activate an immune response, resulting in bystander effects. NsPEFs locally induce apoptosis-like effects and affect vascular networks, both promoting tumor demise and restoration of normal vascular homeostasis. EGT with IL-12 is in melanoma clinical trials and nsPEFs are used in models with B16F10 melanoma in vitro and in …