Characterization of a novel conditional knockout mouse model to assess efficacy of mRNA therapy in the context of severe OTC deficiency.

Ornithine transcarbamylase deficiency (OTCD) is the most common urea-cycle disorder, characterized by hyperammonemia and accompanied by a high unmet patient need. mRNA therapies have been shown to be efficacious in hypomorphic Sparse-fur abnormal skin and hair (Spf-ash) mice, a model of late-onset disease. However, studying the efficacy of ornithine transcarbamylase (OTC) mRNA therapy in traditional knockout mice, a model for severe early-onset OTCD, is hampered by the rapid lethality of the model and poor lipid nanoparticle (LNP) uptake into neonatal mouse liver.

Session 4: mRNA and Self-Amplifying RNA (saRNA): Opportunities for Disease Prevention and Therapy.

The unprecedented speed of developing vaccines against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), responsible for the COVID-19 pandemic, has propelled mRNA technologies into the public eye. The versatility of mRNA technology, often referred to as "plug and play," offers immense promise for rapidly updating vaccines to address newer variants of respiratory diseases and combat emerging infectious diseases and lethal pathogens, such as the Ebolavirus. However, the potential applications of mRNA technology extend well beyond prophylactic vaccines.

Stromal p53 Regulates Breast Cancer Development, the Immune Landscape, and Survival in an Oncogene-Specific Manner.

Unlabelled: Coevolution of tumor cells and adjacent stromal elements is a key feature during tumor progression; however, the precise regulatory mechanisms during this process remain unknown. Here, we show stromal p53 loss enhances oncogenic KrasG12D, but not ErbB2, driven tumorigenesis in murine mammary epithelia. Stroma-specific p53 deletion increases both epithelial and fibroblast proliferation in mammary glands bearing the KrasG12D oncogene in epithelia, while concurrently increasing DNA damage and/or DNA replication stress and decreasing apoptosis in the tumor cells proper.

Intramuscular vaccination of mice with the human herpes simplex virus type-1(HSV-1) VC2 vaccine, but not its parental strain HSV-1(F) confers full protection against lethal ocular HSV-1 (McKrae) pathogenesis.

Herpes simplex virus type-1 (HSV-1) can cause severe ocular infection and blindness. We have previously shown that the HSV-1 VC2 vaccine strain is protective in mice and guinea pigs against genital herpes infection following vaginal challenge with HSV-1 or HSV-2. In this study, we evaluated the efficacy of VC2 intramuscular vaccination in mice against herpetic keratitis following ocular challenge with lethal human clinical strain HSV-1(McKrae).

In utero tobacco smoke exposure alters lung inflammation, viral clearance, and CD8 T-cell responses in neonatal mice infected with respiratory syncytial virus.

Maternal smoking during pregnancy and exposure of infants to cigarette smoke are strongly associated with adverse health effects in childhood including higher susceptibility to respiratory viral infections. Human respiratory syncytial virus (HRSV) is the most important cause of lower respiratory tract infection among young infants. Exacerbation of respiratory disease, including HRSV bronchiolitis and higher susceptibility to HRSV infection, is well correlated with previous smoke exposure.

First Impressions-the Potential of Altering Initial Host-Virus Interactions for Rational Design of Herpesvirus Vaccine Vectors.

Purpose: The earliest host-virus interactions occur during virus attachment and entry into cells. These initial steps in the virus lifecycle influence the outcome of infection beyond delivery of the viral genome into the cell. Herpesviruses alter host signaling pathways and processes during attachment and entry to facilitate virus infection and modulate innate immune responses.

Supplemental Oxygen Protects Heart Against Acute Myocardial Infarction.

Myocardial infarction (MI), which occurs often due to acute ischemia followed by reflow, is associated with irreversible loss (death) of cardiomyocytes. If left untreated, MI will lead to progressive loss of viable cardiomyocytes, deterioration of cardiac function, and congestive heart failure. While supplemental oxygen therapy has long been in practice to treat acute MI, there has not been a clear scientific basis for the observed beneficial effects.

Levels Serve as "Early Signature" Genes in the Development of High-Grade Serous Carcinoma from the Fallopian Tube.

The initial molecular events that lead to malignant transformation of the fimbria of the fallopian tube (FT) through high-grade serous ovarian carcinoma (HGSC) remain poorly understood. In this study, we report that increased expression of signal transducer and activator of transcription 3 () and suppression or loss of protein inhibitor of activated STAT3 () in FT likely drive HGSC. We evaluated human tissues-benign normal FT, tubal-peritoneal junction (TPJ), p53 signature FT tissue, tubal intraepithelial lesion in transition (TILT), serous tubal intraepithelial carcinoma (STIC) without ovarian cancer, and HGSC for expression of (compared with their known signature) and their target proliferation genes.

Intramuscular Immunization of Mice with the Live-Attenuated Herpes Simplex Virus 1 Vaccine Strain VC2 Expressing Equine Herpesvirus 1 (EHV-1) Glycoprotein D Generates Anti-EHV-1 Immune Responses in Mice.

Vaccination remains the best option to combat equine herpesvirus 1 (EHV-1) infection, and several different strategies of vaccination have been investigated and developed over the past few decades. Herein, we report that the live-attenuated herpes simplex virus 1 (HSV-1) VC2 vaccine strain, which has been shown to be unable to enter into neurons and establish latency in mice, can be utilized as a vector for the heterologous expression of EHV-1 glycoprotein D (gD) and that the intramuscular immunization of mice results in strong antiviral humoral and cellular immune responses. The VC2-EHV-1-gD recombinant virus was constructed by inserting an EHV-1 gD expression cassette under the control of the cytomegalovirus immediate early promoter into the VC2 vector in place of the HSV-1 thymidine kinase (UL23) gene.

Neutrophils regulate the lung inflammatory response via γδ T cell infiltration in an experimental mouse model of human metapneumovirus infection.

Neutrophils are the most abundant leukocytes in human circulation. They are the first immune cell population recruited to the sites of infection. However, the role of neutrophils to regulate host immune responses during respiratory viral infections is largely unknown.

Anticancer potential of diarylidenyl piperidone derivatives, HO-4200 and H-4318, in cisplatin resistant primary ovarian cancer.

We have previously developed a novel class of bi-functional compounds based on a diarylidenyl-piperidone (DAP) backbone conjugated to an N-hydroxypyrroline (-NOH; a nitroxide precursor) group capable of selectively inhibiting STAT3 activation, translocation, and DNA binding activity. HO-4200 and H-4318 are 2 such derivatives capable of inducing apoptosis in ovarian cancer cells through this mechanism and demonstrated efficacy in platinum resistant primary ovarian cancer cell populations and tumor tissues. The improved absorption and cellular uptake of HO-4200 by cancer cells was determined using optical and electron paramagnetic resonance spectrometry.

Elevated STAT3 expression in ovarian cancer ascites promotes invasion and metastasis: a potential therapeutic target.

Although activation of the STAT3 pathway has been associated with tumor progression in a wide variety of cancer types (including ovarian cancer), the precise mechanism of invasion and metastasis due to STAT3 are not fully delineated in ovarian cancer. We found that pSTAT3 Tyr705 is constitutively activated in patient ascites and ascites-derived ovarian cancer cells (ADOCCs), and the range of STAT3 expression could be very high to low. In vivo transplantation of ADOCCs with high pSTAT3 expression into the ovarian bursa of mice resulted in a large primary tumor and widespread peritoneal metastases.

Targeting constitutively-activated STAT3 in hypoxic ovarian cancer, using a novel STAT3 inhibitor.

Tumor hypoxia, a feature of many solid tumors including ovarian cancer, is associated with resistance to therapies. We previously demonstrated that hypoxic exposure results in increased expression of phosphorylated signal transducer and activator of transcription 3 (pSTAT3). We hypothesized the activation of STAT3 could lead to chemotherapeutic resistance in ovarian cancer cells in hypoxic conditions.

Comparison of human induced pluripotent stem-cell derived cardiomyocytes with human mesenchymal stem cells following acute myocardial infarction.

Introduction: Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have recently been shown to express key cardiac proteins and improve in vivo cardiac function when administered following myocardial infarction. However, the efficacy of hiPSC-derived cell therapies, in direct comparison to current, well-established stem cell-based therapies, is yet to be elucidated. The goal of the current study was to compare the therapeutic efficacy of human mesenchymal stem cells (hMSCs) with hiPSC-CMs in mitigating myocardial infarction (MI).

Aberrantly activated pSTAT3-Ser727 in human endometrial cancer is suppressed by HO-3867, a novel STAT3 inhibitor.

Objective: Constitutive activation of STAT3 is a hallmark of various human cancers, however an increased pSTAT3 expression in high grade human endometrial cancer has not been reported. In the present study, we examine the expression of STAT family of proteins in endometrial cancer cell lines and the efficacy of HO-3867, a novel STAT3 inhibitor designed in our lab.

Methods: Expression of STAT family proteins was evaluated via Western blot.

Real-time, in vivo determination of dynamic changes in lung and heart tissue oxygenation using EPR oximetry.

The use of electron paramagnetic resonance (EPR) oximetry for oxygen measurements in deep tissues (>1 cm) is challenging due to the limited penetration depth of the microwave energy. To overcome this limitation, implantable resonators, having a small (0.5 mm diameter) sensory loop containing the oxygen-sensing paramagnetic material connected by a pair of twisted copper wire to a coupling loop (8-10 mm diameter), have been developed, which enable repeated measurements of deep-tissue oxygen levels (pO2, partial pressure of oxygen) in the brain and tumors of rodents.

HO-3867, a safe STAT3 inhibitor, is selectively cytotoxic to ovarian cancer.

STAT3 is well corroborated preclinically as a cancer therapeutic target, but tractable translational strategies for its blockade by small molecule inhibitors have remained elusive. In this study, we report the development of a novel class of bifunctional STAT3 inhibitors, based on conjugation of a diarylidenyl-piperidone (DAP) backbone to an N-hydroxypyrroline (-NOH) group, which exhibits minimal toxicity against normal cells and good oral bioavailability. Molecular modeling studies of this class suggested direct interaction with the STAT3 DNA binding domain.

Pulmonary hypertension secondary to left-heart failure involves peroxynitrite-induced downregulation of PTEN in the lung.

Pulmonary hypertension (PH) that occurs after left-heart failure (LHF), classified as Group 2 PH, involves progressive pulmonary vascular remodeling induced by smooth muscle cell (SMC) proliferation. However, mechanisms involved in the activation of SMCs remain unknown. The objective of this study was to determine the involvement of peroxynitrite and phosphatase-and-tensin homolog on chromosome 10 (PTEN) in vascular SMC proliferation and remodeling in the LHF-induced PH (LHF-PH).

Dysregulation of PTEN in cardiopulmonary vascular remodeling induced by pulmonary hypertension.

Pulmonary hypertension (PH) is a disorder of lung vasculature characterized by arterial narrowing. Phosphatase-and-tensin homolog on chromosome 10 (PTEN), associated in the progression of multiple cancers, is implicated in arterial remodeling. However, the involvement of PTEN in PH remains unclear.

Amelioration of doxorubicin-induced cardiotoxicity by an anticancer-antioxidant dual-function compound, HO-3867.

Doxorubicin (DOX) is a drug commonly used for the treatment of cancer. The development of resistance to DOX is common, and high cumulative doses cause potentially lethal cardiac side effects. HO-3867 (3,5-bis(4-fluorobenzylidene)-1-[(2,2,5,5-tetramethyl-2,5-dihydro-1-hydroxy-pyrrol-3-yl)methyl]piperidin-4-one), a synthetic curcumin analog, has been shown to exhibit both anticancer and cardioprotective effects.

Allele-specific tumor spectrum in pten knockin mice.

Germline mutations in the tumor suppressor gene PTEN (phosphatase and tensin homology deleted on chromosome 10) cause Cowden and Bannayan-Riley-Ruvalcaba (BRR) syndromes, two dominantly inherited disorders characterized by mental retardation, multiple hamartomas, and variable cancer risk. Here, we modeled three sentinel mutant alleles of PTEN identified in patients with Cowden syndrome and show that the nonsense Pten(4-5) and missense Pten(C124R) and Pten(G129E) alleles lacking lipid phosphatase activity cause similar developmental abnormalities but distinct tumor spectra with varying severity and age of onset. Allele-specific differences may be accounted for by loss of function for Pten(4-5), hypomorphic function for Pten(C124R), and gain of function for Pten(G129E).

Pten in stromal fibroblasts suppresses mammary epithelial tumours.

The tumour stroma is believed to contribute to some of the most malignant characteristics of epithelial tumours. However, signalling between stromal and tumour cells is complex and remains poorly understood. Here we show that the genetic inactivation of Pten in stromal fibroblasts of mouse mammary glands accelerated the initiation, progression and malignant transformation of mammary epithelial tumours.

Mouse development with a single E2F activator.

The E2F family is conserved from Caenorhabditis elegans to mammals, with some family members having transcription activation functions and others having repressor functions. Whereas C. elegans and Drosophila melanogaster have a single E2F activator protein and repressor protein, mammals have at least three activator and five repressor proteins.