Phase I, multicenter, open-label study of intravenous VCN-01 oncolytic adenovirus with or without nab-paclitaxel plus gemcitabine in patients with advanced solid tumors.

Background: VCN-01 is an oncolytic adenovirus (Ad5 based) designed to replicate in cancer cells with dysfunctional RB1 pathway, express hyaluronidase to enhance virus intratumoral spread and facilitate chemotherapy and immune cells extravasation into the tumor. This phase I clinical trial was aimed to find the maximum tolerated dose/recommended phase II dose (RP2D) and dose-limiting toxicity (DLT) of the intravenous delivery of the replication-competent VCN-01 adenovirus in patients with advanced cancer.

Methods: Part I: patients with advanced refractory solid tumors received one single dose of VCN-01.

VCN-01 disrupts pancreatic cancer stroma and exerts antitumor effects.

Background: Pancreatic ductal adenocarcinoma (PDAC) is characterized by dense desmoplastic stroma that limits the delivery of anticancer agents. VCN-01 is an oncolytic adenovirus designed to replicate in cancer cells with a dysfunctional RB1 pathway and express hyaluronidase. Here, we evaluated the mechanism of action of VCN-01 in preclinical models and in patients with pancreatic cancer.

Hyaluronidase expression within tumors increases virotherapy efficacy and T cell accumulation.

Oncolytic viruses (OVs) preferentially infect and selectively replicate in cancer cells. OVs have been tested in clinical trials as monotherapy or in combination with chemotherapy, radiotherapy, and immunotherapy. However, the dense extracellular matrix hampers the intratumoral spreading and efficacy of OVs.

Oncolytic adenovirus with hyaluronidase activity that evades neutralizing antibodies: VCN-11.

Tumor targeting and intratumoral virus spreading are key features for successful oncolytic virotherapy. VCN-11 is a novel oncolytic adenovirus, genetically modified to express hyaluronidase (PH20) and display an albumin-binding domain (ABD) on the hexon. ABD allows the virus to self-coat with albumin when entering the bloodstream and evade neutralizing antibodies (NAbs).

Evolving Status of Clinical Immunotherapy with Oncolytic Adenovirus.

Cancer immunotherapy targeting immune checkpoint inhibitors shows efficacy in several human cancers, but "cold tumors" that lack immune cells are typically unresponsive. Among the potential therapeutic approaches that could "heat" or promote lymphocyte infiltration of cold tumors, oncolytic viruses have attracted interest for their lytic and immunogenic mechanisms of action. In this article, we review the use of oncolytic adenoviruses in cancer immunotherapy, with a particular focus on preclinical and clinical data of oncolytic adenovirus-triggered immune responses against tumor antigens.

Arming Oncolytic Adenoviruses: Effect of Insertion Site and Splice Acceptor on Transgene Expression and Viral Fitness.

Oncolytic adenoviruses (OAds) present limited efficacy in clinics. The insertion of therapeutic transgenes into OAds genomes, known as "arming OAds", has been the main strategy to improve their therapeutic potential. Different approaches were published in the decade of the 2000s, but with few comparisons.

Safety and efficacy of VCN-01, an oncolytic adenovirus combining fiber HSG-binding domain replacement with RGD and hyaluronidase expression.

Purpose: Tumor targeting upon intravenous administration and subsequent intratumoral virus dissemination are key features to improve oncolytic adenovirus therapy. VCN-01 is a novel oncolytic adenovirus that combines selective replication conditional to pRB pathway deregulation, replacement of the heparan sulfate glycosaminoglycan putative-binding site KKTK of the fiber shaft with an integrin-binding motif RGDK for tumor targeting, and expression of hyaluronidase to degrade the extracellular matrix. In this study, we evaluate the safety and efficacy profile of this novel oncolytic adenovirus.

Inertial cavitation to non-invasively trigger and monitor intratumoral release of drug from intravenously delivered liposomes.

The encapsulation of cytotoxic drugs within liposomes enhances pharmacokinetics and allows passive accumulation within tumors. However, liposomes designed to achieve good stability during the delivery phase often have compromised activity at the target site. This problem of inefficient and unpredictable drug release is compounded by the present lack of low-cost, non-invasive methods to measure such release.

Enhanced tumor uptake and penetration of virotherapy using polymer stealthing and focused ultrasound.

Background: Oncolytic viruses are among the most powerful and selective cancer therapeutics under development and are showing robust activity in clinical trials, particularly when administered directly into tumor nodules. However, their intravenous administration to treat metastatic disease has been stymied by unfavorable pharmacokinetics and inefficient accumulation in and penetration through tumors.

Methods: Adenovirus (Ad) was "stealthed" with a new N-(2-hydroxypropyl)methacrylamide polymer, and circulation kinetics were characterized in Balb/C SCID mice (n = 8 per group) bearing human ZR-75-1 xenograft tumors.

Cavitation-enhanced delivery of a replicating oncolytic adenovirus to tumors using focused ultrasound.

Oncolytic viruses (OV) and ultrasound-enhanced drug delivery are powerful novel technologies. OV selectively self-amplify and kill cancer cells but their clinical use has been restricted by limited delivery from the bloodstream into the tumor. Ultrasound has been previously exploited for targeted release of OV in vivo, but its use to induce cavitation, microbubble oscillations, for enhanced OV tumor extravasation and delivery has not been previously reported.

A non-exothermic cell-embedding tissue-mimicking material for studies of ultrasound-induced hyperthermia and drug release.

Purpose: The present study aims to create and characterise a cell-embedding tissue-mimicking material (TMM) that has thermal and acoustic properties similar to liver tissue, in order to enable study and optimisation of protocols for ultrasound-induced hyperthermia and drug delivery.

Materials And Methods: An agarose-based, cell-embedding TMM was iteratively developed and characterised. The acoustic properties (attenuation coefficient, speed of sound and cavitation threshold) and thermal response of the material were compared with those of fresh degassed liver tissue over a range of acoustic pressures and frequencies.

MEN1 gene replacement therapy reduces proliferation rates in a mouse model of pituitary adenomas.

Multiple endocrine neoplasia type 1 (MEN1) is characterized by the combined occurrence of pituitary, pancreatic, and parathyroid tumors showing loss of heterozygosity in the putative tumor suppressor gene MEN1. This gene encodes the protein menin, the overexpression of which inhibits cell proliferation in vitro. In this study, we conducted a preclinical evaluation of MEN1 gene therapy in pituitary tumors of Men1(+/-) mice, using a recombinant nonreplicating adenoviral serotype 5 vector that contained the murine Men1 cDNA under control of a cytomegalovirus promoter (Men1.

Ultrasound-induced cavitation enhances the delivery and therapeutic efficacy of an oncolytic virus in an in vitro model.

We investigated whether ultrasound-induced cavitation at 0.5 MHz could improve the extravasation and distribution of a potent breast cancer-selective oncolytic adenovirus, AdEHE2F-Luc, to tumour regions that are remote from blood vessels. We developed a novel tumour-mimicking model consisting of a gel matrix containing human breast cancer cells traversed by a fluid channel simulating a tumour blood vessel, through which the virus and microbubbles could be made to flow.

Cavitation-enhanced extravasation for drug delivery.

A flow-through tissue-mimicking phantom composed of a biocompatible hydro-gel with embedded tumour cells was used to assess and optimize the role of ultrasound-induced cavitation on the extravasation of a macromolecular compound from a channel mimicking vessel in the gel, namely a non-replicating luciferase-expressing adenovirus (Ad-Luc). Using a 500 KHz therapeutic ultrasound transducer confocally aligned with a focussed passive cavitation detector, different exposure conditions and burst mode timings were selected by performing time and frequency domain analysis of passively recorded acoustic emissions, in the absence and in the presence of ultrasound contrast agents acting as cavitation nuclei. In the presence of Sonovue, maximum ultraharmonic emissions were detected for peak rarefactional pressures of 360 kPa, and maximum broadband emissions occurred at 1250 kPa.

Cavitation-enhanced delivery of macromolecules into an obstructed vessel.

Poor drug penetration through tumor tissue has emerged as a fundamental obstacle to cancer therapy. The aim of this study was to examine the ability of cavitation instigated by high-intensity focused ultrasound (HIFU) to increase convective transport of a model therapeutic in an in vitro tumor model. Cavitation activity was quantified by analyzing passively recorded acoustic emissions, and mass transfer was quantified using post-treatment image analysis of the distribution of a dye-labeled macromolecule.

Active adenoviral vascular penetration by targeted formation of heterocellular endothelial-epithelial syncytia.

The endothelium imposes a structural barrier to the extravasation of systemically delivered oncolytic adenovirus (Ad). Here, we introduced a transendothelial route of delivery in order to increase tumor accumulation of virus particles (vp) beyond that resulting from convection-dependent extravasation alone. This was achieved by engineering an Ad encoding a syncytium-forming protein, gibbon ape leukemia virus (GALV) fusogenic membrane glycoprotein (FMG).

Real-time optical measurement of biologically relevant thermal damage in tissue-mimicking hydrogels containing bovine serum albumin.

Purpose: In controlled laboratory studies of hyperthermia and thermal ablation, translucent hydrogels containing bovine serum albumin (BSA) are often employed as tissue-mimicking materials due to the change in their opacity that takes place as they accumulate heat damage. In this work we demonstrate the biological relevance of this optical metric of thermal damage, as well as establish the physical mechanisms that link it with quantifiable damage to the proteins embedded in the gel.

Materials And Methods: We applied Fourier transform infrared (FTIR) spectroscopy, turbidity analysis using ultraviolet-visible (UV/VIS) spectroscopy, and size exclusion chromatography (SEC) to samples of heat-treated, aqueous bovine serum albumin (BSA).

Inhibition of delta-like-4-mediated signaling impairs reparative angiogenesis after ischemia.

Rationale: Notch signaling regulates vascular development. However, the implication of the Notch ligand Delta-like 4 (Dll4) in postischemic angiogenesis remains unclear.

Objective: We investigated the role of Dll4/Notch signaling in reparative angiogenesis using a mouse model of ischemia.

Use of tissue-specific microRNA to control pathology of wild-type adenovirus without attenuation of its ability to kill cancer cells.

Replicating viruses have broad applications in biomedicine, notably in cancer virotherapy and in the design of attenuated vaccines; however, uncontrolled virus replication in vulnerable tissues can give pathology and often restricts the use of potent strains. Increased knowledge of tissue-selective microRNA expression now affords the possibility of engineering replicating viruses that are attenuated at the RNA level in sites of potential pathology, but retain wild-type replication activity at sites not expressing the relevant microRNA. To assess the usefulness of this approach for the DNA virus adenovirus, we have engineered a hepatocyte-safe wild-type adenovirus 5 (Ad5), which normally mediates significant toxicity and is potentially lethal in mice.

Role of brain-derived neurotrophic factor in the protective action of N-methyl-D-aspartate in the apoptotic death of cerebellar granule neurons induced by low potassium.

Several neurotrophic factors, including brain-derived neurotrophic factor (BDNF), and neurotransmitters, such as glutamate, may influence neuronal apoptotic death. Rat cerebellar granule neurons (CGN) cultured in low potassium (5 or 10 mM KCl) for more than 5 days in vitro (DIV) die apoptotically. These cells survive in the presence of high potassium (25 mM KCl, K25) or N-methyl-D-aspartate (NMDA), an agonist of glutamatergic receptors.

Adenovirus type 5 interactions with human blood cells may compromise systemic delivery.

Intravenous delivery of adenovirus vectors requires that the virus is not inactivated in the bloodstream. Serum neutralizing activity is well documented, but we show here that type 5 adenovirus also interacts with human blood cells. Over 90% of a typical virus dose binds to human (but not murine) erythrocytes ex vivo, and samples from a patient administered adenovirus in a clinical trial showed that over 98% of viral DNA in the blood was cell associated.