Cell and Developmental Biology Commons^™

Synergistic Effects Of Nanosecond Pulsed Plasma And Electric Field On Inactivation Of Pancreatic Cancer Cells In Vitro, Edwin A. Oshin, Zobia Minhas, Ruben M. L. Colunga Biancatelli, John D. Catravas, Richard Heller, Siqi Guo, Chunqi Jiang

Bioelectrics Publications

Nanosecond pulsed atmospheric pressure plasma jets (ns-APPJs) produce reactive plasma species, including charged particles and reactive oxygen and nitrogen species (RONS), which can induce oxidative stress in biological cells. Nanosecond pulsed electric field (nsPEF) has also been found to cause permeabilization of cell membranes and induce apoptosis or cell death. Combining the treatment of ns-APPJ and nsPEF may enhance the effectiveness of cancer cell inactivation with only moderate doses of both treatments. Employing ns-APPJ powered by 9 kV, 200 ns pulses at 2 kHz and 60-nsPEF of 50 kV/cm at 1 Hz, the synergistic effects on pancreatic cancer cells (Pan02) …

Gene Expression Under Combined Hypoxia And Acidosis In Chondrosarcoma, Michael Stacey, Kostika Vangjeli, Christopher Osgood

Bioelectrics Publications

Chondrosarcomas are the second most common cause of bone cancer and are removed surgically with wide margins. On recurrence, they are resistant to chemo and radiation therapy and new treatment options are critically required. This tumor type produces hyaline cartilage, a cartilage normally formed under hypoxic and acidic environment due to lack of vasculature in cartilage. Paradoxically, chondrosarcomas arise in the well vascularized, oxygen rich environment of the bone. Hypoxia and acidosis are two stressors where the cellular effects are typically reported separately even though cells experience combined effects of hypoxia and acidosis. Given the mechanistic links between hypoxia and …

Identification Of Proteins Involved In Cell Membrane Permeabilization By Nanosecond Electric Pulses (Nsep), Giedre Silkuniene, Uma Mangalanathan, Alessandra Rossi, Peter A. Mollica, Andrei G. Pakhomov, Olga N. Pakhomova

Bioelectrics Publications

The study was aimed at identifying endogenous proteins which assist or impede the permeabilized state in the cell membrane disrupted by nsEP (20 or 40 pulses, 300 ns width, 7 kV/cm). We employed a LentiArray CRISPR library to generate knockouts (KOs) of 316 genes encoding for membrane proteins in U937 human monocytes stably expressing Cas9 nuclease. The extent of membrane permeabilization by nsEP was measured by the uptake of Yo-Pro-1 (YP) dye and compared to sham-exposed KOs and control cells transduced with a non-targeting (scrambled) gRNA. Only two KOs, for SCNN1A and CLCA1 genes, showed a statistically significant reduction in …

Modification Of The Tumor Microenvironment Enhances Anti-Pd-1 Immunotherapy In Metastatic Melanoma, Guilan Shi, Megan Scott, Cathryn G. Mangiamele, Richard Heller

Bioelectrics Publications

Resistance to checkpoint-blockade treatments is a challenge in the clinic. Both primary and acquired resistance have become major obstacles, greatly limiting the long-lasting effects and wide application of blockade therapy. Many patients with metastatic melanoma eventually require further therapy. The absence of T-cell infiltration to the tumor site is a well-accepted contributor limiting immune checkpoint inhibitor efficacy. In this study, we combined intratumoral injection of plasmid IL-12 with electrotransfer and anti-PD-1 in metastatic B16F10 melanoma tumor model to increase tumor-infiltrating lymphocytes and improve therapeutic efficacy. We showed that effective anti-tumor responses required a subset of tumor-infiltrating CD8⁺ and CD4 …

Electroporation And Cell Killing By Milli- To Nanosecond Pulses And Avoiding Neuromuscular Stimulation In Cancer Ablation, Emily Gudvangen, Vitalii Kim, Vitalij Novickij, Federico Battista, Andrei G. Pakhomov

Bioelectrics Publications

Ablation therapies aim at eradication of tumors with minimal impact on surrounding healthy tissues. Conventional pulsed electric field (PEF) treatments cause pain and muscle contractions far beyond the ablation area. The ongoing quest is to identify PEF parameters efficient at ablation but not at stimulation. We measured electroporation and cell killing thresholds for 150 ns–1 ms PEF, uni- and bipolar, delivered in 10- to 300-pulse trains at up to 1 MHz rates. Monolayers of murine colon carcinoma cells exposed to PEF were stained with YO-PRO-1 dye to detect electroporation. In 2–4 h, dead cells were labeled with propidium. Electroporation and …

In Vivo Metabolic Analysis Of The Anticancer Effects Of Plasma-Activated Saline In Three Tumor Animal Models, Miao Qi, Dehui Xu, Shuai Wang, Bing Li, Sansan Peng, Qiaosong Li, Hao Zhang, Runze Fan, Hai-Lan Chen, Michael G. Kong

Bioelectrics Publications

In recent years, the emerging technology of cold atmospheric pressure plasma (CAP) has grown rapidly along with the many medical applications of cold plasma (e.g., cancer, skin disease, tissue repair, etc.). Plasma-activated liquids (e.g., culture media, water, or normal saline, previously exposed to plasma) are being studied as cancer treatments, and due to their advantages, many researchers prefer plasma-activated liquids as an alternative to CAP in the treatment of cancer. In this study, we showed that plasma-activated-saline (PAS) treatment significantly inhibited tumor growth, as compared with saline, in melanoma, and a low-pH environment had little effect on tumor growth in …

Plasmonic-Based Biosensor For The Early Diagnosis Of Prostate Cancer, Thakshila Liyanage, Bayan Alharbi, Linh Quan, Aurora Esquela-Kerscher, Gymama Slaughter

Bioelectrics Publications

A tapered optical fiber (TOF) plasmonic biosensor was fabricated and used for the sensitive detection of a panel of microRNAs (miRNAs) in human serum obtained from noncancer and prostate cancer (PCa) patients. Oncogenic and tumor suppressor miRNAs let7a, let-7c, miR-200b, miR-141, and miR-21 were tested as predictive cancer biomarkers since multianalyte detection minimizes false-positive and false-negative rates and establishes a strong foundation for early PCa diagnosis. The biosensing platform integrates metallic gold triangular nanoprisms (AuTNPs) laminated on the TOF to excite surface plasmon waves in the supporting metallic layer and enhance the evanescent mode of the fiber surface. …

Alkaline Plasma-Activated Water (Paw) As An Innovative Therapeutic Avenue For Cancer Treatment, Bolun Pang, Zhijie Liu, Sitao Wang, Yuting Gao, Miao Qi, Dehui Xu, Renwu Zhou, Dingxin Liu, Michael G. Kong

Bioelectrics Publications

Plasma-activated water (PAW) is considered to be an effective anticancer agent due to the diverse aqueous reactive oxygen and nitrogen species (RONS: ROS and RNS), but the drawback of low dose and short duration of RONS in acidified PAW limits their clinical application. Herein, this Letter presents an innovative therapeutic avenue for cancer treatment with highly-effective alkaline PAW prepared by air surface plasma. This anticancer alkaline formulation is comprised of a rich mixture of highly chemical RONS and exhibited a prolonged half-life compared to acidified PAW. The H₂O₂, NO₂-, and ONOO^-/O_{2 …}

Connexin Hemichannel Activation By S-Nitrosoglutathione Synergizes Strongly With Photodynamic Therapy Potentiating Anti-Tumor Bystander Killing, Chiara Nardin, Chiara Peres, Sabrina Putti, Tiziana Orsini, Claudia Colussi, Flavia Mazzarda, Marcello Raspa, Ferdinando Scavizzi, Anna Maria Salvatore, Francesco Chiani, Abraham Tettey-Matey, Yuanyuan Kuang, Guang Yang, Mauricio A. Retamal, Fabio Mammano

Bioelectrics Publications

In this study, we used B16-F10 cells grown in the dorsal skinfold chamber (DSC) preparation that allowed us to gain optical access to the processes triggered by photodynamic therapy (PDT). Partial irradiation of a photosensitized melanoma triggered cell death in non-irradiated tumor cells. Multiphoton intravital microscopy with genetically encoded fluorescence indicators revealed that bystander cell death was mediated by paracrine signaling due to adenosine triphosphate (ATP) release from connexin (Cx) hemichannels (HCs). Intercellular calcium (Ca²⁺) waves propagated from irradiated to bystander cells promoting intracellular Ca²⁺ transfer from the endoplasmic reticulum (ER) to mitochondria and rapid activation of …

Effect Of He Plasma Jet Versus Surface Plasma On The Metabolites Of Acute Myeloid Leukemia Cells, Dehui Xu, Ning Ning, Yujing Xu, Wenjie Xia, Hai-Lan Chen, Michael G. Kong

Bioelectrics Publications

Cold atmospheric plasma, including plasma jet and surface plasma, can promote the apoptosis of cancer cells without causing significant damage to surrounding normal cells, which was hopeful to be applied to the clinical cancer therapy. However, experimental plasma devices used directly to clinical experiments has challenges in technology and methods, especially the difference in killing tumor cells efficiency of these two common plasma sources. Therefore, it is great necessity to explore the differences in treating tumors between different plasma sources. This paper achieved good killing efficiency by using two kinds of cold atmospheric plasma generating devices, namely plasma jet and …

Stobe Photography Mapping Of Cell Membrane Potential With Nanosecond Resolution, Allen S. Kiester, Bennett L. Ibey, Zachary N. Coker, Andrei G. Pakhomov, Joel N. Bixler

Bioelectrics Publications

The ability to directly observe membrane potential charging dynamics across a full microscopic field of view is vital for understanding interactions between a biological system and a given electrical stimulus. Accurate empirical knowledge of cell membrane electrodynamics will enable validation of fundamental hypotheses posited by the single shell model, which includes the degree of voltage change across a membrane and cellular sensitivity to external electric field non-uniformity and directionality. To this end, we have developed a high-speed strobe microscopy system with a time resolution of ~ 6 ns that allows us to acquire time-sequential data for temporally repeatable events (non-injurious …

Modulation Of Ros In Nanosecond-Pulsed Plasma-Activated Media For Dosage-Dependent Cancer Cell Inactivation In Vitro, Chunqi Jiang, Esin Bengisu Sozer, Shutong Song, Nicola Lai, P. Thomas Vernier, Sigi Guo

Bioelectrics Publications

Dosage control of reactive oxygen and nitrogen species (RONS) is critical to low-temperature plasma applications in cancer therapy. Production of RONS by atmospheric pressure, nonequilibrium plasmas in contact with liquid may be modulated via plasma conditions including plasma treatment time and pulse voltage and repetition frequency. In this study, a terephthalic acid-based probe was used to measure hydroxyl radicals [OH_aq] in water exposed to plasma and to demonstrate that the OH_ag concentration increases linearly with treatment time. Fluorometric measurements of hydrogen peroxide concentration in plasma-activated water show a linear relationship between the H₂O₂ production …

Nanosecond Pulsed Electric Fields Induce Endoplasmic Reticulum Stress Accompanied By Immunogenic Cell Death In Murine Models Of Lymphoma And Colorectal Cancer, Alessandra Rossi, Olga N. Pakhomova, Peter A. Mollica, Maura Casciola, Uma Mangalanathan, Andrei G. Pakhomov, Claudia Muratori

Bioelectrics Publications

Depending on the initiating stimulus, cancer cell death can be immunogenic or non-immunogenic. Inducers of immunogenic cell death (ICD) rely on endoplasmic reticulum (ER) stress for the trafficking of danger signals such as calreticulin (CRT) and ATP. We found that nanosecond pulsed electric fields (nsPEF), an emerging new modality for tumor ablation, cause the activation of the ER-resident stress sensor PERK in both CT-26 colon carcinoma and EL-4 lymphoma cells. PERK activation correlates with sustained CRT exposure on the cell plasma membrane and apoptosis induction in both nsPEF-treated cell lines. Our results show that, in CT-26 cells, the activity of …

Intratumoral Delivery Of Plasmid Il12 Via Electroporation Leads To Regression Of Injected And Noninjected Tumors In Merkel Cell Carcinoma, Shailender Bhatia, Natalie V. Longino, Natalie J. Miller, Rima Kulikauskas, Jayasri G. Iyer, Dafina Ibrani, Astrid Blom, David R. Byrd, Upendra Parvathaneni, Christopher Twitty, Jean S. Campbell, Mai H. Le, Sharron Gargosky, Robert H. Pierce, Richard Heller, Adil Daud, Paul Nghiem

Bioelectrics Publications

Purpose: Interleukin-12 (IL12) promotes adaptive type I immunity and has demonstrated antitumor efficacy, but systemic administration leads to severe adverse events (AE), including death. This pilot trial investigated safety, efficacy, and immunologic activity of intratumoral delivery of IL12 plasmid DNA (tavo) via in vivo electroporation (i.t.-tavo-EP) in patients with Merkel cell carcinoma (MCC), an aggressive virus-associated skin cancer.

Experimental Design: Fifteen patients with MCC with superficial injectable tumor(s) received i.t.-tavo-EP on days 1, 5, and 8 of each cycle. Patients with locoregional MCC (cohort A, N = 3) received one cycle before definitive surgery in week 4. …

Il-12 Gene Electrotransfer Triggers A Change In Immune Response Within Mouse Tumors, Guilan Shi, Chelsea Edelblute, Sezgi Arpag, Cathryn Lundberg, Richard Heller

Bioelectrics Publications

Metastatic melanoma is an aggressive skin cancer with a relatively low survival rate. Immune-based therapies have shown promise in the treatment of melanoma, but overall complete response rates are still low. Previous studies have demonstrated the potential of plasmid IL-12 (pIL-12) delivered by gene electrotransfer (GET) to be an effective immunotherapy for melanoma. However, events occurring in the tumor microenvironment following delivery have not been delineated. Therefore, utilizing a B16F10 mouse melanoma model, we evaluated changes in the tumor microenvironment following delivery of pIL-12 using different GET parameters or injection of plasmid alone. The results revealed a unique immune cell …

Inactivation Of Myeloma Cancer Cells By Helium And Argon Plasma Jets: The Effect Comparison And The Key Reactive Species, Zeyu Chen, Qingjie Cui, Chen Chen, Dehui Xu, Dingxin Liu, H. L. Chen, Michael G. Kong

Bioelectrics Publications

In plasma cancer therapy, the inactivation of cancer cells under plasma treatment is closely related to the reactive oxygen and nitrogen species (RONS) induced by plasmas. Quantitative study on the plasma-induced RONS that related to cancer cells apoptosis is critical for advancing the research of plasma cancer therapy. In this paper, the effects of several reactive species on the inactivation of LP-1 myeloma cancer cells are comparatively studied with variable working gas composition, surrounding gas composition, and discharge power. The results show that helium plasma jet has a higher cell inactivation efficiency than argon plasma jet under the same discharge …

Nanopulse Stimulation (Nps) Induces Tumor Ablation And Immunity In Orthotopic 4t1 Mouse Breast Cancer: A Review, Stephen J. Beebe, Brittany P. Lassiter, Siqi Guo

Bioelectrics Publications

Nanopulse Stimulation (NPS) eliminates mouse and rat tumor types in several different animal models. NPS induces protective, vaccine-like effects after ablation of orthotopic rat N1-S1 hepatocellular carcinoma. Here we review some general concepts of NPS in the context of studies with mouse metastatic 4T1 mammary cancer showing that the postablation, vaccine-like effect is initiated by dynamic, multilayered immune mechanisms. NPS eliminates primary 4T1 tumors by inducing immunogenic, caspase-independent programmed cell death (PCD). With lower electric fields, like those peripheral to the primary treatment zone, NPS can activate dendritic cells (DCs). The activation of DCs by dead/dying cells leads to increases …

Tumor Cell Death After Electrotransfer Of Plasmid Dna Is Associated With Cytosolic Dna Sensor Upregulation, Katarina Znidar, Masa Bosnjak, Nina Semenova, Olga N. Pakhomova, Loree Heller, Maja Cemazar

Bioelectrics Publications

Cytosolic DNA sensors are a subgroup of pattern recognition receptors (PRRs) and are activated by the abnormal presence of the DNA in the cytosol. Their activation leads to the upregulation of pro-inflammatory cytokines and chemokines and can also induce cell death. The presence of cytosolic DNA sensors and inflammatory cytokines in TS/A murine mammary adenocarcinoma and WEHI 164 fibrosarcoma cells was demonstrated using real time reverse transcription polymerase chain reaction (RT-PCR), western blotting and enzyme-linked immunosorbent assay (ELISA). After electrotransfer of plasmid DNA (pDNA) using two pulse protocols, the upregulation of DNA-depended activator of interferon regulatory factor or Z-DNA binding …

Upregulation Of Dna Sensors In B16.F10 Melanoma Spheroid Cells After Electrotransfer Of Pdna, Katarina Znidar, Masa Bosnjak, Tanja Jesenko, Loree C. Heller, Maja Cemazar

Bioelectrics Publications

Increased expression of cytosolic DNA sensors, a category of pattern recognition receptor, after control plasmid DNA electrotransfer was observed in our previous studies on B16.F10 murine melanoma cells. This expression was correlated with the upregulation of proinflammatory cytokines and chemokines and was associated with cell death. Here, we expanded our research to include the influence of features of cells in a 3-dimensional environment, which better represents the tumors’ organization in vivo. Our results show that lower number of cells were transfected in spheroids compared to 2-dimensional cultures, that growth was delayed after electroporation alone or after electrotransfer of plasmid …

Wild-Type P53 Enhances Endothelial Barrier Function By Mediating Rac1 Signalling And Rhoa Inhibition, Nektarios Barabutis, Christiana Dimitropoulou, Betsy Gregory, John D. Catravas

Bioelectrics Publications

Inflammation is the major cause of endothelial barrier hyper-permeability, associated with acute lung injury and acute respiratory distress syndrome. This study reports that p53 "orchestrates" the defence of vascular endothelium against LPS, by mediating the opposing actions of Rac1 and RhoA in pulmonary tissues. Human lung microvascular endothelial cells treated with HSP90 inhibitors activated both Rac1- and P21-activated kinase, which is an essential element of vascular barrier function. 17AAG increased the phosphorylation of both LIMK and cofilin, in contrast to LPS which counteracted those effects. Mouse lung microvascular endothelial cells exposed to LPS exhibited decreased expression of phospho-cofilin. 17AAG treatment …

Alteration Of Metabolite Profiling By Cold Atmospheric Plasma Treatment In Human Myeloma Cells, Dehui Xu, Yujing Xu, Ning Ning, Qingjie Cui, Zhijie Liu, Xiaohua Wang, Dingxin Liu, Hailan Chen, Michael G. Kong

Bioelectrics Publications

BACKGROUND: Despite new progress of chemotherapy in multiple myeloma (MM) clinical treatment, MM is still a refractory disease and new technology is needed to improve the outcomes and prolong the survival. Cold atmospheric plasma is a rapidly developed technology in recent years, which has been widely applied in biomedicine. Although plasma could efficiently inactivate various tumor cells, the effects of plasma on tumor cell metabolism have not been studied yet.

METHODS: In this study, we investigated the metabolite profiling of He plasma treatment on myeloma tumor cells by gas-chromatography time-of-flight (GC-TOF) mass-spectrometry. Meanwhile, by bioinformatic analysis such as GO and …

Nano-Pulse Stimulation Ablates Orthotopic Rat Hepatocellular Carcinoma And Induces Innate And Adaptive Memory Immune Mechanisms That Prevent Recurrence, Brittany P. Lassiter, Siqi Guo, Stephen J. Beebe

Bioelectrics Publications

Nano-pulse stimulation (NPS), previously called nsPEFs, induced a vaccine-like effect after ablation of orthotopic N1-S1 hepatocellular carcinoma (HCC), protecting rats from subsequent challenges with N1-S1 cells. To determine immunity, immune cell phenotypes were analyzed in naïve, treated and protected rats. NPS provides a positive, post-ablation immuno-therapeutic outcome by alleviating immunosuppressive T regulatory cells (Treg) in the tumor microenvironment (TME), allowing dendritic cell influx and inducing dynamic changes in natural killer cells (NKs), NKT-cells and T-lymphocytes in blood, spleen and liver. NPS induced specific increases in NKs and NKT-cells expressing CD8 and activation receptors CD314-NKG2D and CD161 (NK1.1) in the TME …

Electrotransfer Of Different Control Plasmids Elicits Different Antitumor Effectiveness In B16.F10 Melanoma, Masa Bosnjak, Tanjo Jesenko, Urska Kamensek, Gregor Sersa, Jaka Lavrencak, Loree Heller, Maja Cemazar

Bioelectrics Publications

Several studies have shown that different control plasmids may cause antitumor action in different murine tumor models after gene electrotransfer (GET). Due to the differences in GET protocols, plasmid vectors, and experimental models, the observed antitumor effects were incomparable. Therefore, the current study was conducted comparing antitumor effectiveness of three different control plasmids using the same GET parameters. We followed cytotoxicity in vitro and the antitumor effect in vivo after GET of control plasmids pControl, pENTR/U6 scr and pVAX1 in B16.F10 murine melanoma cells and tumors. Types of cell death and upregulation of selected cytosolic DNA sensors and cytokines were …

Cold Atmospheric Plasma As A Potential Tool For Multiple Myeloma Treatment, Dehui Xu, Yujing Xu, Qingjie Cui, Dingxin Liu, Zhijie Liu, Xiaohua Wang, Yanjie Yang, Niaojuan Feng, Rong Liang, Hailan Chen, Kai Ye, Michael G. Kong

Bioelectrics Publications

Multiple myeloma (MM) is a fatal and incurable hematological malignancy thus new therapy need to be developed. Cold atmospheric plasma, a new technology that could generate various active species, could efficiently induce various tumor cells apoptosis. More details about the interaction of plasma and tumor cells need to be addressed before the application of gas plasma in clinical cancer treatment. In this study, we demonstrate that He+O₂ plasma could efficiently induce myeloma cell apoptosis through the activation of CD95 and downstream caspase cascades. Extracellular and intracellular reactive oxygen species (ROS) accumulation is essential for CD95-mediated cell apoptosis in response …

Nano-Pulse Stimulation For The Treatment Of Pancreatic Cancer And The Changes In Immune Profile, Sigi Guo, Niculina I. Burcus, James Hornef, Yu Jing, Chunqi Jiang, Richard Heller, Stephen J. Beebe

Bioelectrics Publications

A Pancreatic cancer is a notorious malignant neoplasm with an extremely poor prognosis. Current standard of care is rarely effective against late-stage pancreatic cancer. In this study, we assessed nanopulse stimulation (NPS) as a local treatment for pancreatic cancer in a syngeneic mouse Pan02 pancreatic cancer model and characterized corresponding changes in the immune profile. A single NPS treatment either achieved complete tumor regression or prolonged overall survival in animals with partial tumor regression. While this is very encouraging, we also explored if this local ablation effect could also result in immune stimulation, as was observed when NPS led to …

Enhanced Electric Pulse Technology For The Ablation Of Pancreatic Cancer, Siqi Guo, Niculina I. Burcus, Chelsea M. Edelblute, James Hornef, Chunqi Jiang, Karl Schoenbach, Richard Heller, Stephen J. Beebe

Bioelectrics Publications

Electric pulse based technology has been developed and studied as a non-thermal ablation method for local control of pancreatic cancer. Irreversible electroporation (IRE) has shown a significant survival benefit for local advanced pancreatic cancer in clinical trials. However, incomplete ablation with local recurrence and major complications limit the potential of this new technology. We have developed an integrated moderate heating electric pulse delivery system which consists of controllable tumor heating, multi-parameter monitoring and electric pulse delivery. The impedance of tumor is greatly decreased after moderate heating at 42°C for 1–2 min, which does not cause any cell death. Moderate heating …

Anti-Proliferative Role Of Recombinant Lethal Toxin Of Bacillus Anthracis On Primary Mammary Ductal Carcinoma Cells Revealing Its Therapeutic Potential, Rekha Khandia, Bramhadev Pattnaik, Katherikamem Rajukumar, Atul Pateriya, Sandeep Bhatia, Harshad Murugkar, Anil Prakash, Hare Krishna Pradhan, Kildeep Dhama, Ashol Munjal, Sunil K. Joshi

Bioelectrics Publications

Bacillus anthracis secretes three secretary proteins; lethal factor (LF), protective antigen (PA) and edema factor (EF). The LF has ability to check proliferation of mammary tumors, chiefly depending on mitogen activated protein kinase (MAPK) signaling pathway. Evaluation of therapeutic potential of recombinant LF (rLF), recombinant PA (rPA) and lethal toxin (rLF + rPA = LeTx) on the primary mammary ductal carcinoma cells revealed significant (p < 0.01) reduction in proliferation of tumor cells with mean inhibition indices of 28.0 ±1.37% and 19.6 ± 1.47% respectively. However, treatment with rPA alone had no significant anti-proliferative effect as evident by low mean inhibition index of 3.4 ± 3.87%. The higher inhibition index observed for rLF alone as compared to LeTx is contrary to the existing knowledge on LF, which explains the requirement of PA dependent endocytosis for its enzymatic activity. Therefore, the plausible existence of PA independent mode of action of LF including direct receptor mediated endocytosis or modulation of signal transduction cascade via unknown means is hypothesized. In silico protein docking analysis of other cellular receptors for any plausibility to play the role of receptor for LF revealed c-Met receptor showing strongest affinity for LF (H bond = 19; Free energy = …

Effect Of Twisted Fiber Anisotropy In Cardiac Tissue On Ablation With Pulsed Electric Fields, Fei Xie, Christian W. Zemlin

Bioelectrics Publications

Background: Ablation of cardiac tissue with pulsed electric fields is a promising alternative to current thermal ablation methods, and it critically depends on the electric field distribution in the heart.

Methods: We developed a model that incorporates the twisted anisotropy of cardiac tissue and computed the electric field distribution in the tissue. We also performed experiments in rabbit ventricles to validate our model. We find that the model agrees well with the experimentally determined ablation volume if we assume that all tissue that is exposed to a field greater than 3 kV/cm is ablated. In our numerical analysis, we considered …

Radio-Frequency Plasma Polymerized Biodegradable Carrier For In Vivo Release Of Cis-Platinum, Sudhir Bhatt, Fatemeh Valamanesh, Jerome Pulpytel, Rea Lo Dico, Aliby Baiyukha, Iman Al-Dybiat, Marc Pocard, Farzaneh Arefi-Khonsari, Massoud Mirshahi

Bioelectrics Publications

A low pressure plasma process based on plasma deposition has been used to develop a drug delivery strategy. In this study, a drug delivery system based on different layers of plasma co-polymerized Poly ε-caprolactone-Polyethylene glycol (PCL-PEG) co-polymers was deposited on biocompatible substrates. Cis-platinum (118 μgm/cm²) was used as an anti-cancer drug and incorporated for local delivery of the chemotherapeutic agent. The co-polymer layers and their interaction with cancer cells were analyzed by scanning electron microscopy. Our study showed that the plasma-PCL-PEG coated cellophane membranes, in which the drug, was included did not modify the flexibility and appearance of …

Mechanisms Of Nanosecond Pulsed Electric Field (Nspef)-Induced Cell Death In Cells And Tumors, Stephen J. Beebe

Bioelectrics Publications

The evolution of pulse power technology from high power physics to biology and medicine places nanosecond pulsed electric fields (nsPEFs) in positions for in vitro and in vivo applications as non-ligand agonists that not only bypass plasma membrane receptors for induction of intracellular signaling pathways, but also bypass intracellular oncogenic impasses to induce cell death by regulated mechanisms. Based on work reviewed here, a likely scenario for cell and tumor demise includes nsPEF-induced permeabilization of the plasma membrane, Ca2+ influx, dissipation of the mitochondrial membrane potential, which is likely due to events beyond permeabilization of the inner mitochondrial membrane, cytochrome …