Histone modifiers at the crossroads of oncolytic and oncogenic viruses.

Cancer is a disease caused by loss of regulatory processes that control the cell cycle, resulting in increased proliferation. The loss of control can deregulate both tumor suppressors and oncogenes. Apart from cell intrinsic gene mutations and environmental factors, infection by cancer-causing viruses also induces changes that lead to malignant transformation. This can be caused by both expression of oncogenic viral proteins and also by changes in cellular genes and proteins that affect the epigenome. Thus, these epigenetic modifiers are good therapeutic targets, and several epigenetic inhibitors are approved for the treatment of different cancers. In addition to small molecule drugs, biological therapies, such as antibodies and viral therapies, are also increasingly being used to treat cancer. An HSV-1-derived oncolytic virus is currently approved by the US FDA and the European Medicines Agency. Similarly, an adenovirus-based therapeutic is approved for use in China for some cancer types. Because viruses can affect cellular epigenetics, the interaction of epigenome-targeting drugs with oncogenic and oncolytic viruses is a highly significant area of investigation. Here, we will review the current knowledge about the impact of using epigenetic drugs in tumors positive for oncogenic viruses or as therapeutic combinations with oncolytic viruses.

Prospective measurements of hearing threshold during military rifle training with in-ear, protected, noise exposure monitoring.

Although a causal relationship exists between military occupational noise exposure and hearing loss, researchers have struggled to identify and/or characterize specific operational noise exposures that produce measurable changes in hearing function shortly following an exposure. Growing evidence suggests that current standards for noise-exposure limits are not good predictors of true hearing damage. In this study, the aim was to capture the dose-response relationship during military rifle training exercises for noise exposure and hearing threshold. To capture exposure, a wearable system capable of measuring impulse noise simultaneously on-body and in-ear, behind hearing protection was used. To characterize hearing threshold changes, portable audiometry was employed within 2 h before and after exposure. The median 8-h time-weighted, protected, free-field equivalent in-ear exposure was 87.5 dBA at one site and 80.7 dBA at a second site. A significant dose-response correlation between in-ear noise exposure and postexposure hearing threshold changes across our population ( R = 0.40 , p = 0.0281) was observed. The results demonstrate an approach for establishing damage risk criteria (DRC) for in-ear, protected measurements based on hearing threshold changes. While an in-ear DRC does not currently exist, it may be critical for predicting the risk of injury for noise environments where protection is mandatory and fit status can vary.

Distortion product otoacoustic mapping measured pre- and post-loud sound exposures.

OBJECTIVE: Sampling distortion product otoacoustic emissions (DPOAEs) at multiple f2/f1 ratios and f2 frequency values produces a DPOAE "map." This study examined the efficacy of DPOAE mapping compared with pure tone audiometry and standard DPOAEs for detecting noise effects in subjects exposed to loud sound. DESIGN: A map significance score was developed as a single measure of map change. Significance scores were evaluated before and after exposure to: loud music (LM), controlled noise (CN), and firing range noise (FR) in three separate sets of subjects. Scores were compared to audiometry and standard DPOAE results in the LM study. STUDY SAMPLE: The LM and CN exposure studies involved 22, and 20 healthy young subjects respectively with normal hearing. Eight Marines were studied before and after FR exposure. RESULTS: After LM exposure, audiometry showed significant changes at 1, 2, 4, and 6 kHz. Standard DPOAE measures were also significantly different at several frequencies. Map significance scores detected changes more effectively and showed the distribution of DPOAE alterations. CONCLUSIONS: Map significance scores detected changes after noise exposure more reliably than audiometry and standard DPOAEs. Additionally, maps showed a diffuse response to sound exposure perhaps explaining why individual DP-grams appear less sensitive.

Vascular Smooth Muscle Remodeling in Conductive and Resistance Arteries in Hypertension.

Cardiovascular disease is a leading cause of death worldwide and accounts for >17.3 million deaths per year, with an estimated increase in incidence to 23.6 million by 2030. 1 Cardiovascular death represents 31% of all global deaths 2 -with stroke, heart attack, and ruptured aneurysms predominantly contributing to these high mortality rates. A key risk factor for cardiovascular disease is hypertension. Although treatment or reduction in hypertension can prevent the onset of cardiovascular events, existing therapies are only partially effective. A key pathological hallmark of hypertension is increased peripheral vascular resistance because of structural and functional changes in large (conductive) and small (resistance) arteries. In this review, we discuss the clinical implications of vascular remodeling, compare the differences between vascular smooth muscle cell remodeling in conductive and resistance arteries, discuss the genetic factors associated with vascular smooth muscle cell function in hypertensive patients, and provide a prospective assessment of current and future research and pharmacological targets for the treatment of hypertension.

Interaction Between Pannexin 1 and Caveolin-1 in Smooth Muscle Can Regulate Blood Pressure.

Objective- Sympathetic nerve innervation of vascular smooth muscle cells (VSMCs) is a major regulator of arteriolar vasoconstriction, vascular resistance, and blood pressure. Importantly, α-adrenergic receptor stimulation, which uniquely couples with Panx1 (pannexin 1) channel-mediated ATP release in resistance arteries, also requires localization to membrane caveolae. Here, we test whether localization of Panx1 to Cav1 (caveolin-1) promotes channel function (stimulus-dependent ATP release and adrenergic vasoconstriction) and is important for blood pressure homeostasis. Approach and Results- We use in vitro VSMC culture models, ex vivo resistance arteries, and a novel inducible VSMC-specific Cav1 knockout mouse to probe interactions between Panx1 and Cav1. We report that Panx1 and Cav1 colocalized on the VSMC plasma membrane of resistance arteries near sympathetic nerves in an adrenergic stimulus-dependent manner. Genetic deletion of Cav1 significantly blunts adrenergic-stimulated ATP release and vasoconstriction, with no direct influence on endothelium-dependent vasodilation or cardiac function. A significant reduction in mean arterial pressure (total=4 mm Hg; night=7 mm Hg) occurred in mice deficient for VSMC Cav1. These animals were resistant to further blood pressure lowering using a Panx1 peptide inhibitor Px1IL2P, which targets an intracellular loop region necessary for channel function. Conclusions- Translocalization of Panx1 to Cav1-enriched caveolae in VSMCs augments the release of purinergic stimuli necessary for proper adrenergic-mediated vasoconstriction and blood pressure homeostasis.

Targeting IGF2-IGF1R Signaling to Reprogram the Tumor Microenvironment for Enhanced Viro-Immunotherapy.

BACKGROUND: The FDA approval of oncolytic herpes simplex-1 virus (oHSV) therapy underscores its therapeutic promise and safety as a cancer immunotherapy. Despite this promise, the current efficacy of oHSV is significantly limited to a small subset of patients largely due to the resistance in tumor and tumor microenvironment (TME). METHODS: RNA sequencing (RNA-Seq) was used to identify molecular targets of oHSV resistance. Intracranial human and murine glioma or breast cancer brain metastasis (BCBM) tumor-bearing mouse models were employed to elucidate the mechanism underlying oHSV therapy-induced resistance. RESULTS: Transcriptome analysis identified IGF2 as one of the top secreted proteins following oHSV treatment. Moreover, IGF2 expression was significantly upregulated in 10 out of 14 recurrent GBM patients after treatment with oHSV, rQNestin34.5v.2 (71.4%) (p=0.0020) (ClinicalTrials.gov, NCT03152318). Depletion of IGF2 substantially enhanced oHSV-mediated tumor cell killing in vitro and improved survival of mice bearing BCBM tumors in vivo. To mitigate the oHSV-induced IGF2 in the TME, we constructed a novel oHSV, oHSV-D11mt, secreting a modified IGF2R domain 11 (IGF2RD11mt) that acts as IGF2 decoy receptor. Selective blocking of IGF2 by IGF2RD11mt significantly increased cytotoxicity, reduced oHSV-induced neutrophils/PMN-MDSCs infiltration, and reduced secretion of immune suppressive/proangiogenic cytokines, while increased CD8+cytotoxic T lymphocytes (CTLs) infiltration, leading to enhanced survival in GBM or BCBM tumor-bearing mice. CONCLUSION: This is the first study reporting that oHSV-induced secreted IGF2 exerts a critical role in resistance to oHSV therapy, which can be overcome by oHSV-D11mt as a promising therapeutic advance for enhanced viro-immunotherapy.

NOTCH-Induced MDSC Recruitment after oHSV Virotherapy in CNS Cancer Models Modulates Antitumor Immunotherapy.

PURPOSE: Oncolytic herpes simplex virus-1 (oHSV) infection of brain tumors activates NOTCH, however the consequences of NOTCH on oHSV-induced immunotherapy is largely unknown. Here we evaluated the impact of NOTCH blockade on virus-induced immunotherapy. EXPERIMENTAL DESIGN: RNA sequencing (RNA-seq), TCGA data analysis, flow cytometry, Luminex- and ELISA-based assays, brain tumor animal models, and serum analysis of patients with recurrent glioblastoma (GBM) treated with oHSV was used to evaluate the effect of NOTCH signaling on virus-induced immunotherapy. RESULTS: TCGA data analysis of patients with grade IV glioma and oHSV treatment of experimental brain tumors in mice showed that NOTCH signaling significantly correlated with a higher myeloid cell infiltration. Immunofluorescence staining and RNA-seq uncovered a significant induction of Jag1 (NOTCH ligand) expression in infiltrating myeloid cells upon oHSV infection. Jag1-expressing macrophages further spread NOTCH activation in the tumor microenvironment (TME). NOTCH-activated macrophages increased the secretion of CCL2, which further amplified myeloid-derived suppressor cells. CCL2 and IL10 induction was also observed in serum of patients with recurrent GBM treated with oHSV (rQnestin34.5; NCT03152318). Pharmacologic blockade of NOTCH signaling rescued the oHSV-induced immunosuppressive TME and activated a CD8-dependent antitumor memory response, resulting in a therapeutic benefit. CONCLUSIONS: NOTCH-induced immunosuppressive myeloid cell recruitment limited antitumor immunity. Translationally, these findings support the use of NOTCH inhibition in conjunction with oHSV therapy.

ATF3 Coordinates Antitumor Synergy between Epigenetic Drugs and Protein Disulfide Isomerase Inhibitors.

Histone deacetylase inhibitors (HDACi) are largely ineffective in the treatment of solid tumors. In this study, we describe a new class of protein disulfide isomerase (PDI) inhibitors that significantly and synergistically enhance the antitumor activity of HDACi in glioblastoma and pancreatic cancer preclinical models. RNA-sequencing screening coupled with gene silencing studies identified ATF3 as the driver of this antitumor synergy. ATF3 was highly induced by combined PDI and HDACi treatment as a result of increased acetylation of key histone lysine residues (acetylated histone 3 lysine 27 and histone 3 lysine 18) flanking the ATF3 promoter region. These chromatin marks were associated with increased RNA polymerase II recruitment to the ATF3 promoter, a synergistic upregulation of ATF3, and a subsequent apoptotic response in cancer cells. The HSP40/HSP70 family genes DNAJB1 and HSPA6 were found to be critical ATF3-dependent genes that elicited the antitumor response after PDI and HDAC inhibition. In summary, this study presents a synergistic antitumor combination of PDI and HDAC inhibitors and demonstrates a mechanistic and tumor suppressive role of ATF3. Combined treatment with PDI and HDACi offers a dual therapeutic strategy in solid tumors and the opportunity to achieve previously unrealized activity of HDACi in oncology. SIGNIFICANCE: This study uses a first-in-class PDI inhibitor entering clinical development to enhance the effects of epigenetic drugs in some of the deadliest forms of cancer.

Replacement Therapies in Metabolic Disease.

BACKGROUND: Replacement therapies have revolutionized treatment paradigms in metabolic diseases by restoring defective enzymes and supplementing missing downstream metabolites. Through most of the 20th century, no targeted therapies existed for these conditions, the only treatment options available focusing on symptoms rather than the underlying disorders. Improved understanding of the molecular pathways underlying metabolic disease has allowed not only supplementation of missing metabolites and reduction of upstream substrates, but replacement of defective or missing enzymes. OBJECTIVE: Modern genetic technologies have facilitated steady progress in recombinant enzyme innovation, providing treatments that replicate not only endogenous enzymes, but also their posttranslational modifications to optimize their delivery and function. The advent of the gene therapy revolution brings a possibility of new therapeutic opportunities in which the enzymes at the core of metabolic diseases may not only be added back, but genetically replaced. CONCLUSION: With the next generation of treatments approaching, this review examines the recent decades of replacement therapy innovation in metabolic disease and discusses the challenges and opportunities for the next generation of treatments.