A cell-based platform to potentiate oncolytic virus: Potential approach for cancer therapies.

21 Background: Oncolytic virotherapy has been pursued by multiple companies and institutions with few candidates reaching the clinic and demonstrating limited efficacy. The therapeutic potential of oncolytic viruses can be severely restricted by innate and adaptive immune barriers. To overcome this obstacle, we load and protect tumor selective CAL1 oncolytic vaccinia virus into adipose-derived stem cells (AD-MSC) to generate a new therapeutic agent called SNV1(SuperNova1). Methods: SNV1s were generated by incubating AD-MSC with CAL1 virus. SNV1 was analyzed for its ability to kill cancer cell lines and protect virus in the presence of active neutralizing antibodies and complement. In animals, SNV1 was intratumorally injected in various xenograft and syngeneic models. Viral biodistribution was also evaluated by PCR. Immune infiltration were analyzed using flow cytometry. Results: Compared to the naked virus, SNV1 showed improved protection against the humoral barriers and efficient eradication of various human cancer cell lines in vitro. Intratumoral SNV1 treatment showed statistically significant and potentiated tumor growth inhibition compared to control or CAL1 naked virus treatment in all tested models (prostate, breast, melanoma, colon, and prostate cancers). Importantly, local administration of SNV1 induced systemic therapeutic effects. Five days after SNV1 administration, tumor infiltrating lymphocytes (TILs) from both treated and untreated tumors showed increased CD4 and CD8 T-cell populations. As well as decreased frequency of Tregs, and improved effector to Treg ratios, which was associated with inhibition of tumor growth at the treated tumor site and also at distant untreated sites. Ongoing and persistent virus infection could be detected in the treated tumor as late as 15 days after administration. Conclusions: This study demonstrates the ability of our cell-based platform to protect and potentiate oncolytic vaccinia virus by circumventing the innate and adaptive immune barriers, resulting in enhanced oncolytic virotherapy. These findings provide fundamental rationale for the development of cell-based platforms to maximize the therapeutic potential of various oncolytic viruses.

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716 Cell-based virotherapy for targeting cancers

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2020-sitc2020.0716 ◽

2020 ◽

Vol 8 (Suppl 3) ◽

pp. A758-A758

Author(s):

Duong Nguyen ◽

Alberto Gomez ◽

Forrest Neuharth ◽

Ashley Alamillo ◽

Thomas Herrmann ◽

...

Keyword(s):

Stem Cells ◽

Vaccinia Virus ◽

Cancer Cells ◽

Neutralizing Antibodies ◽

Immune Cell ◽

Human Cancer ◽

Oncolytic Viruses ◽

Oncolytic Virotherapy ◽

Adaptive Immune ◽

Immune Barriers

BackgroundOncolytic virotherapy has been recognized as a promising new therapy for cancer for decades but only few viruses have been approved worldwide. The therapeutic potential of oncolytic viruses can be severely restricted by innate and adaptive immune barriers making oncolytic virus clinically inefficient. To overcome this obstacle, we utilized adipose-derived stem cells (AD-MSC) loaded with tumor selective CAL1 oncolytic vaccinia virus to generate a new therapeutic agent called SNV1 (SuperNova-1).MethodsCAL1 vaccinia virus was tested for its ability to replicate and selectively kill various human cancer cell lines in vitro and in vivo. Additionally, CAL1 was loaded into adipose-derived mesenchymal stem cells to generate SuperNova1 (SNV1). Both CAL1 and SNV1 were tested for their ability to kill cancer cells in the presence of active complement and neutralizing antibodies in cell culture as well as in mice. Immune cell infiltration of the treated and untreated tumors was analyzed by flow cytometry.ResultsCAL1 showed preferential amplification and killed various tested human (PC3, FaDu, MDA-MB-231, RPMI) and mouse cancer cells (CT26, EMT6, TRAMP-C2, RM1). In animals, CAL1 caused tumor regression in PC3 and CT26 mouse models without signs of toxicity. SNV1 significantly enhanced protection of CAL1 virus from clearance by the immune system as compared to naked CAL1 virus, leading to higher therapeutic efficacy in animals. Five days after SNV1 administration, tumor infiltrating lymphocytes (TILs) from both treated and untreated tumors showed increased CD4 and CD8 T-cell infiltrations. Importantly, we documented a decreased frequency of Tregs, and improved effector to Treg ratios, which was associated with inhibition of tumor growth at the treated tumor site and also at distant untreated sites.ConclusionsCAL1 is potentially used as an oncolytic agent. In addition, SNV1 cell-based platform protects and potentiates oncolytic vaccinia virus by circumventing humoral innate and adaptive immune barriers, resulting in enhanced oncolytic virotherapy. Particularly, SNV1 provided instantly active viral particles for immediate infection and simultaneous release of therapeutic proteins in the injected tumors.

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Generation of Genetically RGD σ1-Modified Oncolytic Reovirus That Enhances JAM-A-Independent Infection of Tumor Cells

Journal of Virology ◽

10.1128/jvi.01703-20 ◽

2020 ◽

Vol 94 (23) ◽

Author(s):

Takahiro Kawagishi ◽

Yuta Kanai ◽

Ryotaro Nouda ◽

Ichika Fukui ◽

Jeffery A. Nurdin ◽

...

Keyword(s):

Cell Lines ◽

Cancer Cell ◽

Cell Attachment ◽

Genetically Modified ◽

Cancer Cell Lines ◽

Oncolytic Viruses ◽

Peptide Sequence ◽

Attachment Protein ◽

Low Levels ◽

Entry Receptor

ABSTRACT Mammalian reovirus (MRV) strain type 3 Dearing (T3D) is a naturally occurring oncolytic virus that has been developed as a potential cancer therapeutic. However, MRV treatment cannot be applied to cancer cells expressing low levels of junctional adhesion molecule A (JAM-A), which is the entry receptor of MRV. In this study, we developed a reverse genetics system for MRV strain T3D-L, which showed high oncolytic potency. To modify the cell tropism of MRV, an arginine–glycine–aspartic acid (RGD) peptide with an affinity to integrin was inserted at the C terminus or loop structures of the viral cell attachment protein σ1. The recombinant RGD σ1-modified viruses induced remarkable cell lysis in human cancer cell lines with marginal JAM-A expression and in JAM-A knockout cancer cell lines generated by a CRISPR/Cas9 system. Pretreatment of cells with anti-integrin antibody decreased cell death caused by the RGD σ1-modified virus, suggesting the infection to the cells was via a specific interaction with integrin αV. By using mouse models, we assessed virulence of the RGD σ1-modified viruses in vivo. This system will open new avenues for the use of genetically modified oncolytic MRV for use as a cancer therapy. IMPORTANCE Oncolytic viruses kill tumors without affecting normal cells. A variety of oncolytic viruses are used as cancer therapeutics. Mammalian reovirus (MRV), which belongs to the genus Orthoreovirus, family Reoviridae, is one such natural oncolytic virus. The anticancer effects of MRV are being evaluated in clinical trials. Unlike other oncolytic viruses, MRV has not been genetically modified for use as a cancer therapeutic in clinical trials. Here, we used a reverse genetic approach to introduce an integrin-affinity peptide sequence into the MRV cell attachment protein σ1 to alter the natural tropism of the virus. The recombinant viruses were able to infect cancer cell lines expressing very low levels of the MRV entry receptor, junctional adhesion molecule A (JAM-A), and cause tumor cell death while maintaining its original tropism via JAM-A. This is a novel report of a genetically modified oncolytic MRV by introducing a peptide sequence into σ1.

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Redox Modulation at Work: Natural Phytoprotective Polysulfanes From Alliums Based on Redox-Active Sulfur

Current Pharmacology Reports ◽

10.1007/s40495-018-0153-2 ◽

2018 ◽

Vol 4 (5) ◽

pp. 397-407 ◽

Cited By ~ 5

Author(s):

Awais Anwar ◽

Emma Gould ◽

Ryan Tinson ◽

Javaid Iqbal ◽

Chris Hamilton

Keyword(s):

Cell Lines ◽

Cancer Cell ◽

Therapeutic Potential ◽

Antimicrobial Properties ◽

Molecular Targets ◽

Cancer Cell Lines ◽

Special Focus ◽

Anticancer Activities ◽

Comprehensive Overview ◽

Anticancer Properties

Abstract Purpose of review This article provides a brief overview of natural phytoprotective products of allium with a special focus on the therapeutic potential of diallyl polysulfanes from garlic, their molecular targets and their fate in the living organisms. A comprehensive overview of antimicrobial and anticancer properties of published literature is presented for the reader to understand the effective concentrations of polysulfanes and their sensitivity towards different human pathogenic microbes, fungi, and cancer cell lines. Recent findings The article finds polysulfanes potentials as new generation novel antibiotics and chemo preventive agent. The effective dose rates of polysulfanes for antimicrobial properties are in the range of 0.5–40 mg/L and for anticancer 20–100 μM. The molecular targets for these redox modulators are mainly cellular thiols as well as inhibition and/or activation of certain cellular proteins in cancer cell lines. Summary Antimicrobial and anticancer activities of polysulfanes published in the literature indicate that with further development, they could be promising candidates for cancer prevention due to their selectivity towards abnormal cells.

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Hemimethylation Patterns in Breast Cancer Cell Lines

Cancer Informatics ◽

10.1177/1176935119872959 ◽

2019 ◽

Vol 18 ◽

pp. 117693511987295 ◽

Cited By ~ 1

Author(s):

Shuying Sun ◽

Yu Ri Lee ◽

Brittany Enfield

Keyword(s):

Breast Cancer ◽

Dna Methylation ◽

Tumor Growth ◽

Cell Lines ◽

Cancer Cell ◽

Breast Cancer Cell ◽

Cancer Cell Lines ◽

Breast Cancer Cell Lines ◽

Entire Genome ◽

Cpg Sites

DNA methylation is an epigenetic event that involves adding a methyl group to the cytosine (C) site, especially the one that pairs with a guanine (G) site (ie, CG or CpG site), in a human genome. This event plays an important role in both cancerous and normal cell development. Previous studies often assume symmetric methylation on both DNA strands. However, asymmetric methylation, or hemimethylation (methylation that occurs only on 1 DNA strand), does exist and has been reported in several studies. Due to the limitation of previous DNA methylation sequencing technologies, researchers could only study hemimethylation on specific genes, but the overall genomic hemimethylation landscape remains relatively unexplored. With the development of advanced next-generation sequencing techniques, it is now possible to measure methylation levels on both forward and reverse strands at all CpG sites in an entire genome. Analyzing hemimethylation patterns may potentially reveal regions related to undergoing tumor growth. For our research, we first identify hemimethylated CpG sites in breast cancer cell lines using Wilcoxon signed rank tests. We then identify hemimethylation patterns by grouping consecutive hemimethylated CpG sites based on their methylation states, methylation “M” or unmethylation “U.” These patterns include regular (or consecutive) hemimethylation clusters (eg, “MMM” on one strand and “UUU” on another strand) and polarity (or reverse) clusters (eg, “MU” on one strand and “UM” on another strand). Our results reveal that most hemimethylation clusters are the polarity type, and hemimethylation does occur across the entire genome with notably higher numbers in the breast cancer cell lines. The lengths or sizes of most hemimethylation clusters are very short, often less than 50 base pairs. After mapping hemimethylation clusters and sites to corresponding genes, we study the functions of these genes and find that several of the highly hemimethylated genes may influence tumor growth or suppression. These genes may also indicate a progressing transition to a new tumor stage.

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Xenografting of Cancer Cell Lines for In Vivo Screening of the Therapeutic Potential of HDAC Inhibitors

Methods in Molecular Biology - HDAC/HAT Function Assessment and Inhibitor Development ◽

10.1007/978-1-4939-6527-4_15 ◽

2016 ◽

pp. 211-215 ◽

Cited By ~ 1

Author(s):

Daniel Nettersheim ◽

Sina Jostes ◽

Hubert Schorle

Keyword(s):

Cell Lines ◽

Cancer Cell ◽

Therapeutic Potential ◽

Hdac Inhibitors ◽

Cancer Cell Lines ◽

In Vivo Screening

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Quercetin conjugated with silica nanoparticles inhibits tumor growth in MCF-7 breast cancer cell lines

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2018.04.174 ◽

2018 ◽

Vol 500 (4) ◽

pp. 860-865 ◽

Cited By ~ 22

Author(s):

Fahimeh Aghapour ◽

Ali Akbar Moghadamnia ◽

Andrea Nicolini ◽

Seydeh Narges Mousavi Kani ◽

Ladan Barari ◽

...

Keyword(s):

Breast Cancer ◽

Tumor Growth ◽

Silica Nanoparticles ◽

Cell Lines ◽

Cancer Cell ◽

Breast Cancer Cell ◽

Cancer Cell Lines ◽

Breast Cancer Cell Lines ◽

Mcf 7

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Inhibition of cMET in an experimental model of pancreatic cancer.

Journal of Clinical Oncology ◽

10.1200/jco.2013.31.4_suppl.185 ◽

2013 ◽

Vol 31 (4_suppl) ◽

pp. 185-185

Author(s):

Sven A. Lang ◽

Franziska Brandes ◽

Edward K. Geissler

Keyword(s):

Pancreatic Cancer ◽

Tumor Growth ◽

Cancer Cells ◽

Cell Lines ◽

Cancer Cell ◽

Pancreatic Cancer Cell ◽

Cancer Cell Lines ◽

Human Pancreatic Cancer ◽

Oncogenic Signaling

185 Background: In human pancreatic cancer, expression of cMET is associated with poor survival. So far, activation/expression of cMET by hepatocyte growth factor (HGF) has been shown to induce proliferation and motility in cancer cells. Therefore, we hypothesized that inhibition of cMET in human pancreatic cancer cell lines impairs oncogenic signaling and tumor growth. Methods: Pancreatic cancer cell lines (HPAF-II, MiaPaCa2, L3.6pl, BxPC3, Panc02) and the cMET inhibitor INC280 (Novartis Oncology, Basel) were used. MiaPaCa2 and L3.6pl pancreatic cancer cells were grown with gemcitabine up to 500 and 250 nM, respectively (then called MiaPaCa2(G500) and L3.6pl(G250)). MTT and Boyden Chamber assays were used to determine effects of INC280 on growth and motility of cells in vitro. Expression of growth factor receptors, activation of signaling intermediates and expression of transcription factors were assessed by Western blotting. Finally, in vitro results were validated in an orthotopic tumor model using L3.6pl pancreatic cancer cell line. Results: All pancreatic cancer cell lines showed expression of cMET. In vitro treatment of cancer cells with INC280 led to a minor, dose-dependent inhibition of growth even when cells were supplemented with HGF. In contrast, migration assays showed a significant reduction of cancer cell motility upon INC280 when cells were stimulated with HGF (P<0.05). Regarding oncogenic signaling, INC280 led to inhibition of HGF-induced phosphorylation of AKT, ERK and FAK. In addition, c-Myc expression was diminished in cancer cells. Interestingly, gemcitabine resistant cell line MiaPaCa2(G500) showed higher cMET expression levels compared to the normal MiaPaCa2. Stimulation of MiaPaCa2(G500) with HGF led to strong induction of oncogenic signaling and tumor cell motility, an effect that was significantly diminished by INC280. Moreover, results from in vivo experiments show that therapy with INC280 (10 mg/kg/d) significantly reduces tumor growth as determined by final tumor weight (P<0.05). Conclusions: In pancreatic cancer cell lines, targeting cMET with INC280 abrogates oncogenic signaling in vitro and impairs tumor growth in vivo. Therefore, the concept of cMET inhibition warrants further preclinical evaluation.

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