Tiffanie Stewart

Targeted and controlled anticancer drug delivery and release with magnetoelectric nanoparticles.

It is a challenge to eradicate tumor cells while sparing normal cells. We used magnetoelectric nanoparticles (MENs) to control drug delivery and release. The physics is due to electric-field interactions (i) between MENs and a drug and (ii) between drug-loaded MENs and cells. MENs distinguish cancer cells from normal cells through the membrane’s electric properties; cancer cells have a significantly smaller threshold field to induce electroporation. In vitro and in vivo studies (nude mice with SKOV-3 xenografts) showed that (i) drug (paclitaxel (PTX)) could be attached to MENs (30-nm CoFe2O4@BaTiO3 nanostructures) through surface functionalization to avoid its premature release, (ii) drug-loaded MENs could be delivered into cancer cells via application of a d.c. field (~100 Oe), and (iii) the drug could be released off MENs on demand via application of an a.c. field (~50 Oe, 100 Hz). The cell lysate content was measured with scanning probe microscopy and spectrophotometry. MENs and control ferromagnetic and polymer nanoparticles conjugated with HER2-neu antibodies, all loaded with PTX were weekly administrated intravenously. Only the mice treated with PTX-loaded MENs (15/200 μg) in a field for three months were completely cured, as confirmed through infrared imaging and post-euthanasia histology studies via energy-dispersive spectroscopy and immunohistochemistry.

Physics considerations in targeted anticancer drug delivery by magnetoelectric nanoparticles

In regard to cancer therapy, magnetoelectric nanoparticles (MENs) have proven to be in a class of its own when compared to any other nanoparticle type. Like conventional magnetic nanoparticles, they can be used for externally controlled drug delivery via application of a magnetic field gradient and image-guided delivery. However, unlike conventional nanoparticles, due to the presence of a non-zero magnetoelectric effect, MENs provide a unique mix of important properties to address key challenges in modern cancer therapy: (i) a targeting mechanism driven by a physical force rather than antibody matching, (ii) a high-specificity delivery to enhance the cellular uptake of therapeutic drugs across the cancer cell membranes only, while sparing normal cells, (iii) an externally controlled mechanism to release drugs on demand, and (iv) a capability for image guided precision medicine. These properties separate MEN-based targeted delivery from traditional biotechnology approaches and lay a foundation for the comp...

Multiferroic coreshell magnetoelectric nanoparticles as NMR sensitive nanoprobes for cancer cell detection

Magnetoelectric (ME) nanoparticles (MENs) intrinsically couple magnetic and electric fields. Using them as nuclear magnetic resonance (NMR) sensitive nanoprobes adds another dimension for NMR detection of biological cells based on the cell type and corresponding particle association with the cell. Based on ME property, for the first time we show that MENs can distinguish different cancer cells among themselves as well as from their normal counterparts. The core-shell nanoparticles are 30 nm in size and were not superparamagnetic. Due to presence of the ME effect, these nanoparticles can significantly enhance the electric field configuration on the cell membrane which serves as a signature characteristic depending on the cancer cell type and progression stage. This was clearly observed by a significant change in the NMR absorption spectra of cells incubated with MENs. In contrast, conventional cobalt ferrite magnetic nanoparticles (MNPs) did not show any change in the NMR absorption spectra. We conclude that different membrane properties of cells which result in distinct MEN organization and the minimization of electrical energy due to particle binding to the cells contribute to the NMR signal. The nanoprobe based NMR spectroscopy has the potential to enable rapid screening of cancers and impact next-generation cancer diagnostic exams.

Caffeine and Insomnia in People Living With HIV From the Miami Adult Studies on HIV (MASH) Cohort

&NA; We explored the relationship between caffeine consumption, insomnia, and HIV disease progression (CD4+ T cell counts and HIV viral loads). Caffeine intake and insomnia levels were measured using the Modified Caffeine Consumption Questionnaire and the Pittsburgh Insomnia Rating Scale (PIRS) in 130 clinically stable participants who were living with HIV, taking antiretroviral therapy, and recruited from the Miami Adult Studies on HIV cohort. Linear regressions showed that caffeine consumption was significantly and adversely associated with distress score, quality‐of‐life score, and global PIRS score. Linear regression analyses also showed that global PIRS score was significantly associated with lower CD4+ T cell counts and higher HIV viral loads. Caffeine could have precipitated insomnia in susceptible people living with HIV, which could be detrimental to their disease progression states.

Abstract B47: A novel mechanism for field-controlled high-specificity targeted anticancer drug delivery and on-demand release using magnetoelectric nanoparticles

Background: An important challenge in chemotherapy is targeted drug delivery to eradicate tumor cells while sparing normal cells. The circulatory system can deliver a drug to almost every cell in the body; however, delivering the drug specifically into the tumor cell and then releasing it on demand remains a formidable task. Nanoparticles posses unique properties to address this issue. Despite their great potential, a significant problem remains to ensure that the drug is not prematurely released in the plasma or interstitial space but is released at an appropriate rate once at the target site. Recently, we discovered a new class of “smart” multifunctional nanostructures known as magnetoelectric nanoparticles (MENs) that enables a high-efficacy “communication” between intrinsic electric fields at the intra-cellular level, which are inherent to the cellular membrane nature, and external magnetic fields, to control targeted drug delivery and release into specific tumor cells on demand. Herein, the results of a comprehensive in vitro study and an in vivo study on using MENs to treat ovarian cancer (OC) are presented. Methods: A specific combination of d.c. and a.c.-magnetic fields is used to externally control and separate delivery and release functions, respectively. MENs in a wide diameter range, 5-1000nm, are made of coreshell CoFe2O4@BaTiO3 nanostructures. The novel approach is compared to current state-of-the-art nanotechnology deliveries including (i) active immunochemotherapeutic approaches using polymer nanoparticles conjugated with monoclonal antibodies (mAbs) and (ii) passive enhanced permeability and retention (EPR)-based approach using polymer nanoparticles without any immunoactive reagents. Mitotic inhibitor paclitaxel (PTX)–loaded MENs are administrated through systemic IV injection into a lateral tail vein or through localized subcutaneous injection directly into the tumor site. The tumor progression is monitored through infrared (IR) imaging witth mAb-conjugated fluorescent agent Her2Sense 645. Post euthanasia, the cell morphology and the tumor presence in different organs are further studied with HE 2015 Oct 23-26; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2016;76(3 Suppl):Abstract nr B47.

Abstract 2199: Magnetoelectric nanoparticles for high-specificity treatment of cancer

Introduction: Delivering a drug specifically into the tumor cell past its membrane and then releasing the drug into the tumor cells without affecting the normal cells remains a formidable challenge. Unlike any other nanoparticles, magnetoelectric nanoparticles (MENs) display a non-zero magnetoelectric (ME) effect and thus present a unique capability to use external magnetic fields to control intrinsic electric fields associated with cell membranes and the interaction between MENs and therapeutic loads. Because cancer and normal cells of the same type have different electric properties, MENs is used for high-specificity targeted delivery. An a.c. magnetic field is used to trigger drug release off the nanoparticles. Brief Methods: 30-nm CoFe 2 O 4 -BaTiO 3 core shell MENs, with a magnetization of 1 emu/g, a coercivity of 300 Oe, and a ME coefficient of 10-100 mV cm -1 Oe -1 were prepared with a coprecipitation process. MENs were coated with fluorescein isothiocyanate to monitor their intra-cellular transport through a high-contrast confocal microscopy. Three cancer cell lines including Skov-3 (Ovarian adenocarcinoma), U87-MG (Glioblastoma), and MCF-7A (Breast adenocarcinoma), and two normal cell lines including brain endothelial cells (Brain EC) and ovarian cells HOMEC were cultured at 37°C. The transport of MENs loaded with drugs, peptides, and RNAs through the cell membranes and the consequent release of the load under different d.c. and a.c. magnetic fields were studied through confocal microscopy and photoabsorption spectroscopy, respectively. Trypan-blue viability count was used to assess cell growth inhibition under different study conditions. Atomic force microscopy of the cell membranes was conducted to understand the interaction between the nanoparticles and the cells. Summary of new data: Comparison of MENs with purely magnetic iron oxide nanoparticles showed that the penetration through the cancer cell membrane could be achieved only with MENs. It took d.c. fields of 100 Oe and over 1000 Oe to nanoelectroporate the membranes of SKOV-3 and HOMEC cell lines, respectively. An a.c. magnetic field with a strength of 50 Oe and a near-d.c. frequency of 100 Hz was sufficient to enable release of a therapeutic load off MENs. All the cancer cell lines under study showed membrane penetration threshold d.c. fields at least a factor of ten smaller compared to their normal counterparts. Conclusion: MENs displayed unique capabilities for externally controlled high-specificity targeted anticancer drug delivery and release on demand via application of d.c. and a.c. magnetic fields, respectively. Because MENs rely on a physical mechanism rather than antibody-mediated delivery, they can be used for high specificity delivery and high-efficacy controlled release of a broad range of therapeutic loads including drugs, peptides, and RNAs to treat many different cancers. Citation Format: Emmanuel Stimphil, Abhi Nagesetti, Tiffanie S. Stewart, Alexa Rodzinski, Rakesh Guduru, Ping Liang, Carolyn Runowicz, Sakhrat Khizroev. Magnetoelectric nanoparticles for high-specificity treatment of cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2199. doi:10.1158/1538-7445.AM2017-2199

Lower Plasma Zinc Levels in Hyperglycemic People Living with HIV in the MASH cohort.

BACKGROUND Zinc deficiency is prevalent in HIV and hyperglycemic patients. Antiretroviral therapy (ART) is a treatment to control HIV progression; however it increases the risk for hyperglycemia. The objective of this study was to assess the plasma zinc levels in hyperglycemic people living with HIV (PLWH). METHODS Secondary analysis was conducted on the data from the Miami Adult Studies in HIV (MASH) cohort in Florida. Patients were categorized into hyperglycemic group (fasting blood glucose ≥100 mg/dL) and normal group (<100 mg/dL). RESULTS Plasma zinc status and CD4 levels were lower in the hyperglycemic group, however the difference was not significant. There was a greater percentage of plasma zinc deficiency in the hyperglycemic group (69%) compared to the normoglycemic group (64%). DISCUSSION Although not statistically significant, related biomarkers such as plasma zinc levels and CD4 levels were lower in the hyperglycemic group. This may be due to the role zincplays in the immune system. Due to the fact that there was a higher percentage of plasma zinc deficiency in the hyperglycemic group (69%) compared to the normoglycemic group (64%), it is important to monitor and manage blood glucose levels to minimize complications. Our findings along with previous findings suggest that zinc supplementation may benefit hyperglycemic PLWH.

Abstract 2204: Targeted, controlled anticancer drug delivery and release with magnetoelectric nanoparticles

Most cancer therapy is nonspecific, aimed at all dividing cells, resulting in untoward side effects. Our study demonstrates the effectiveness of magnetoelectric nanoparticles (MENs), which have been developed to address the critical issue of normal cell off-targeting in cancer treatment, in both in-vitro and in-vivo studies, as well as characterizes their biodistribution and clearance. Exploiting the difference in electric properties between normal and cancer cell membranes, MENs are able to enter cancerous cells carrying a therapeutic payload and release the payload intracellularly with the application of an external magnetic field, while not affecting normal cells. SKOV-3 human ovarian carcinoma cells were used as a model to showcase the unique cancer targeting capabilities of these CoFe2O4@BaTiO3 nanostructures coated with the mitotic inhibitor Paclitaxel (PTX). The MENs-PTX bond was characterized in the lysate of treated cells using spectroscopic analysis and scanning probe microscopy. SKOV-3 xenografted athymic nude mice were treated via subcutaneous or IV injection on a weekly basis with a MEN, conventional ferromagnetic nanoparticle (MN), or polymer nanoparticle (PLGA) formulation. Biodistribution and clearance of MENs is one of the most important open questions addressed in this study. Our approach is to investigate the key parameters that affect the therapeutic index, i.e. the maximum tolerated dose, blood circulation half-life and biodistribution due organ accumulation. The approach is to study factors such as the size and shape of MENs, chemical composition, targeting ligand functionalization, MENs’ biodegradability, and microenvironment and other biological barriers. Besides using conventional fluorescent markers, a novel nanoparticle distribution approach based on energy-dispersion spectroscopy (EDS) is exploited. In-vitro studies on the cell lysate of MENs treated SKOV-3 cells determined reliable entry into the cells by MENs with the application of a small magnetic field (∼100 Oe) and reliable payload release with the application of an a.c. magnetic field (∼50 Oe, 100 Hz). In-vivo studies demonstrated that the MENs-PTX formulation in combination with an externally applied magnetic field reduces tumor growth rate when injected subcutaneously, and fully cures the cancer when delivered via IV-injection. The MENs formulation was more successful in treating the tumor than both MN and PLGA formulations. EDS confirmed the presence of MENs in tumor tissues. MENs provide a novel mechanism by which cancer cells are targeted (using the difference in the cancer electric cell membrane properties compared to normal cells) and a drug payload is released (externally triggered with the application of an a.c. magnetic field) reliably. The underlying physics of the electric field interactions involved in the MENs drug delivery system was demonstrated here using ovarian cancer, but can be applied to virtually any cancer. Citation Format: Alexandra Rodzinski, Rakesh Guduru, Emmanuel Stimphil, Tiffanie Stewart, Ping Liang, Carolyn Runowicz, Sakhrat Khizroev. Targeted, controlled anticancer drug delivery and release with magnetoelectric nanoparticles. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2204.

Abstract 1346: Magnetoelectric particles cross blood brain barrier to deliver anti-tumor peptide to glioblastoma cells with on-demand release

Background: Despite significant progress in targeted drug delivery, glioblastoma is one of the least treatable tumors today. Delivering therapy across the blood-brain barrier (BBB) and overcoming resistance of tumor cells to current treatments remains a formidable task. The objective of the current in vitro and in vivo study was to show how a new class of multifunctional nanoparticles termed magnetoelectric nanoparticles (MENs) are used to achieve high-efficacy delivery of a therapeutic load across BBB, then release the load on demand, without affecting normal cells, via application of a specially tailored command sequence of D.C. and A.C. magnetic fields. Methods: Growth hormone (GH)-releasing hormone (GHRH) antagonists, a class of anti-tumor peptides, block the release of tumorigenic insulin-like growth factors. Glioblastoma cell line U87 MG were treated with 1 μM of GHRH antagonist MIA-690 bound to GMO-MENs in MEM media supplemented with 5% FBS and 1% penstrep. In parallel, an in vitro BBB experiment, designed using transwells, applied a D.C. magnetic field gradient to determine optimal field and exposure time for MENs to penetrate the BBB. Next, experimental cells were placed on a D.C. magnetic field (100 Oe) for 12 h to induce nanoelectroporation, then an A.C. field (∼50 Hz) for 2 h to release the peptide intracellularly. Control cells were treated with MIA-690 peptide only, GMO-MENs only, and MIA-690 bound to GMO-MENs at varying magnetic fields and exposure times. Cells were incubated at 37°C with 5% CO2 in a humidified atmosphere. At 24 h and 48 h post-treatment, trypan-blue vital stain assessed cell growth inhibition. Cells were then washed and lysed to measure the concentration of MENs, and MIA-690 using ICP-MS and spectrophotometry, respectively. AFM and SEM-EDS imaged MENs in cell lysate and brain tissue from mice IV injected with MENs, to find signature peaks of Ba and Ti representing the outer core of MENs, to ascertain if particles cross the BBB in vivo. Summary of data: Glioblastoma cells treated with MIA-690 bound to GMO-MENs on a D.C. magnetic field for 12 h, then an A.C. field for 2 h exhibited the greatest penetration of MENs and inhibition of tumor growth. AFM and SEM-EDS imaging showed MENs in cell lysate treated with D.C. for 12 h, but not 2 h or with no magnetic field, confirming application of a low D.C. field for 12 h triggers MENs’ penetration. On-demand MIA-690 intracellular release was highest after exposure to 12 h of D.C. field, then A.C. field at 50 Hz. Confocal microscopy confirmed a transfer of at least 50% of drug-loaded MENs across in vitro BBB, requiring 200 Oe/cm for 5 h. SEM-EDS images of brain slices taken from mice treated with MENs confirmed the presence of Ba and Ti, indicating MENs are able to cross BBB in vivo. Conclusion: Functionalized MENs are effective in treating glioblastomas using targeted, on-demand release of anti-tumor drug with the ability to cross the BBB. Citation Format: Tiffanie Stewart, Emmanuel Stimphil, Rakesh Guduru, Alexandra Rodzinski, Ping Liang, Carolyn Runowicz, Ren-Zhi Cai, Luis Salgueiro, Andrew Schally, Sakhrat Khizroev. Magnetoelectric particles cross blood brain barrier to deliver anti-tumor peptide to glioblastoma cells with on-demand release. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1346.

Statistical Estimates from Black Non-Hispanic Female Breast Cancer Data

BACKGROUND The use of statistical methods has become an imperative tool in breast cancer survival data analysis. The purpose of this study was to develop the best statistical probability model using the Bayesian method to predict future survival times for the black non-Hispanic female breast cancer patients diagnosed during 1973- 2009 in the U.S. MATERIALS AND METHODS We used a stratified random sample of black non-Hispanic female breast cancer patient data from the Surveillance Epidemiology and End RESULTS (SEER) database. Survival analysis was performed using Kaplan-Meier and Cox proportional regression methods. Four advanced types of statistical models, Exponentiated Exponential (EE), Beta Generalized Exponential (BGE), Exponentiated Weibull (EW), and Beta Inverse Weibull (BIW) were utilized for data analysis. The statistical model building criteria, Akaike Information Criteria (AIC), Bayesian Information Criteria (BIC), and Deviance Information Criteria (DIC) were used to measure the goodness of fit tests. Furthermore, we used the Bayesian approach to obtain the predictive survival inferences from the best-fit data based on the exponentiated Weibull model. RESULTS We identified the highest number of black non-Hispanic female breast cancer patients in Michigan and the lowest in Hawaii. The mean (SD), of age at diagnosis (years) was 58.3 (14.43). The mean (SD), of survival time (months) for black non- Hispanic females was 66.8 (30.20). Non-Hispanic blacks had a significantly increased risk of death compared to Black Hispanics (Hazard ratio: 1.96, 95%CI: 1.51-2.54). Compared to other statistical probability models, we found that the exponentiated Weibull model better fits for the survival times. By making use of the Bayesian method predictive inferences for future survival times were obtained. CONCLUSIONS These findings will be of great significance in determining appropriate treatment plans and health-care cost allocation. Furthermore, the same approach should contribute to build future predictive models for any health related diseases.