Preclinical Research Articles

Evaluation of the Wound Healing Potential of Aloe Vera Leaf Extract Containing Carbopol 934 as a Gelling Agent and Comparing with Sodium CMC and HPMC on Surgically Induced in Wound Wister Rats: A Preclinical Study

ABSTRACT Introduction: The restricted injury can occur in any tissue or organ and is caused by an external source. The toughness and adaptability of the delivery system are enhanced by the synthetic hydrophilic, biocompatible, and biodegradable stable polymer known as carbopol 934. Aloe vera is a plant belonging to the Liliaceae family that releases anthraquinones, a bitter liquid that has medicinal qualities. Aim: The current study is to determine if aloe vera gel containing Carbopol 934 can cure wounds in animal models used in experiments. Need of the Study: This review will offer a thorough examination of recent studies on the medicinal use of Aloe vera gel. Further study is required to establish the mechanism of action because certain areas, such as wound healing, have not received much attention in the scientific community. However, these biological materials must first be appropriately isolated and identified. Materials and Methods: Various centralizations of Carbopol 934, sodium CMC, and HPMC will be attempted, and lastly, gel that showed great spreadability and consistency will be chosen for wound mending properties of homegrown Aloe vera gel.

Revolutionizing Patient Safety: Machine Learning and AI for the Early Detection of Adverse Drug Reactions and Drug-Induced Toxicity

Adverse drug reactions and drug-induced toxicity provide significant issues in drug research, jeopardizing patient safety and driving up healthcare costs. Toxicity has a greater potential impact than infectious diseases since it is less visible. Early diagnosis of these difficulties is critical to determining a drug's safety and viability profile. The combination of machine learning and artificial intelligence has marked a watershed moment in the identification of early adverse drug reactions and toxicity. These computational approaches enable rapid, extensive, and precise prediction of likely adverse drug reactions and toxicity even before practical drug manufacture, preclinical testing, and clinical trials. This paradigm change strives to create more efficient and safe drugs, lowering the likelihood of drug withdrawal. This comprehensive review investigates the critical role of machine learning and artificial intelligence in quickly detecting adverse drug reactions and toxicity, including approaches from data mining to deep learning. It lists essential databases, modelling techniques, and software that may be used to model and predict a wide range of toxicities and adverse drug reactions. This review provides a comprehensive overview, outlining recent developments and projecting future opportunities in machine learning and artificial intelligence-driven rapid identification of adverse drug reactions and drug-induced toxicity. It highlights the capabilities of these technologies and their enormous potential to improve patient safety and revolutionize medication discovery.

Predictive immunoinformatics reveal promising safety and anti-onchocerciasis protective immune response profiles to vaccine candidates (Ov-RAL-2 and Ov-103) in anticipation of phase I clinical trials.

Onchocerciasis (river blindness) is a debilitating tropical disease that causes significant eye and skin damage, afflicting millions worldwide. As global efforts shift from disease management to elimination, vaccines have become crucial supplementary tools. The Onchocerciasis Vaccine for Africa (TOVA) Initiative was established in 2015, to advance at least one vaccine candidate initially targeting onchocerciasis in infants and children below 5 years of age, through Phase I human trials by 2025. Notably, Ov-RAL-2 and Ov-103 antigens have shown great promise during pre-clinical development, however, the overall success rate of vaccine candidates during clinical development remains relatively low due to certain adverse effects and immunogenic limitations. This study, thus, aimed at predicting the safety and immunogenicity of Ov-RAL-2 and Ov-103 potential onchocerciasis vaccine candidates prior to clinical trials. Advanced molecular simulation models and analytical immunoinformatics algorithms were applied to predict potential adverse side effects and efficacy of these antigens in humans. The analyses revealed that both Ov-RAL-2 and Ov-103 demonstrate favourable safety profiles as toxicogenic and allergenic epitopes were found to be absent within each antigen. Also, both antigens were predicted to harbour substantial numbers of a wide range of distinct epitopes (antibodies, cytokines, and T- Cell epitopes) associated with protective immunity against onchocerciasis. In agreement, virtual vaccination simulation forecasted heightened, but sustained levels of primary and secondary protective immune responses to both vaccine candidates over time. Ov-103 was predicted to be non-camouflageable, as it lacked epitopes identical to protein sequences in the human proteome. Indeed, both antigens were able to bind with high affinity and activate the innate immune TLR4 receptor, implying efficient immune recognition. These findings suggest that Ov-RAL-2 and Ov-103 can induce sufficient protective responses through diverse humoral and cellular mechanisms. Overall, our study provides additional layer of evidence for advancing the clinical development of both vaccine candidates against onchocerciasis.

From TCR fundamental research to innovative chimeric antigen receptor design.

Engineered T cells that express chimeric antigen receptors (CARs) have transformed the treatment of haematological cancers. CARs combine the tumour-antigen-binding function of antibodies with the signalling functions of the T-=cell receptor (TCR) ζ chain and co-stimulatory receptors. The resulting constructs aim to mimic the TCR-based and co-receptor-based activation of T cells. Although these have been successful for some types of cancer, new CAR formats are needed, to limit side effects and broaden their use to solid cancers. Insights into the mechanisms of TCR signalling, including the identification of signalling motifs that are not present in the TCR ζ chain and mechanistic insights in TCR activation, have enabled the development of CAR formats that outcompete the current CARs in preclinical mouse models and clinical trials. In this Perspective, we explore the mechanistic rationale behind new CAR designs.

Clinical Insights and Future Prospects: A Comprehensive Narrative Review on Immunomodulation Induced by Electrochemotherapy.

Electrochemotherapy (ECT) is an emerging therapeutic approach gaining growing interest for its potential immunomodulatory effects in cancer treatment. This narrative review systematically examines the current state of knowledge regarding the interplay between ECT and the immune system. Through an analysis of preclinical and clinical studies, the review highlights ECT capacity to induce immunogenic cell death, activate dendritic cells, release tumor antigens, trigger inflammatory responses, and occasionally manifest systemic effects-the abscopal phenomenon. These mechanisms collectively suggest the ECT potential to influence both local tumor control and immune responses. While implications for clinical practice appear promising, warranting the consideration of ECT as a complementary treatment to immunotherapy, the evidence remains preliminary. Consequently, further research is needed to elucidate the underlying mechanisms, optimize treatment protocols, explore potential synergies, and decipher the parameters influencing the abscopal effect. As the field advances, the integration of ECT's potential immunomodulatory aspects into clinical practice will need careful evaluation and collaboration among clinical practitioners, researchers, and policymakers.

Psilocybin reduces heroin seeking behavior and modulates inflammatory gene expression in the nucleus accumbens and prefrontal cortex of male rats.

Preclinical and human studies indicate psilocybin may reduce perseverant maladaptive behaviors, including nicotine and alcohol seeking. Such studies in the opioid field are lacking, though opioids are involved in >50% of overdose deaths. Psilocybin is an agonist at the serotonin 2A receptor (5-HT2AR), a well-documented target for modulation of drug seeking, and evidence suggests 5-HT2AR agonists may dampen motivation for opioids. We sought to investigate the therapeutic efficacy of psilocybin in mediating cessation of opioid use and maintenance of long-lasting abstinence from opioid seeking behavior in a rat model of heroin self-administration (SA). Psilocybin or 5-HT2AR antagonists ketanserin and volinanserin were administered systemically to rats prior to SA of 0.075 mg/kg/infusion of heroin, or relapse following forced abstinence. Psilocybin did not alter heroin taking, but a single exposure to 3.0 mg/kg psilocybin 4-24 h prior to a relapse test blunted cue-induced heroin seeking. Conversely, 5-HT2AR antagonists exacerbated heroin relapse. To begin to elucidate mechanisms of psilocybin, drug-naïve rats received psilocybin and/or ketanserin, and tissue was collected from the prefrontal cortex (PFC), a region critical for drug seeking and responsive to psilocybin, 24 h later for RNA-sequencing. 3.0 mg/kg psilocybin regulated ~2-fold more genes in the PFC than 1.0 mg/kg, including genes involved in the cytoskeleton and cytokine signaling. Ketanserin blocked >90% of psilocybin-regulated genes, including the IL-17a cytokine receptor, Il17ra. Psychedelic compounds have reported anti-inflammatory properties, and therefore we performed a gene expression array to measure chemokine/cytokine molecules in the PFC of animals that displayed psilocybin-mediated inhibition of heroin seeking. Psilocybin regulated 4 genes, including Il17a, and a subset of genes correlated with relapse behavior. Selective inhibition of PFC IL-17a was sufficient to reduce heroin relapse. We conclude that psilocybin reduces heroin relapse and highlight IL-17a signaling as a potential downstream pathway of psilocybin that also reduces heroin seeking.

From Chaos to Clarity? The Quest for Effective Probiotics in Antibiotic-Associated Diarrhea

Abstract Antibiotic associated diarrhea frequently complicates treatment of infections. A recent randomized, double-blind, placebo-controlled trial tested a proprietary probiotic mixture and found it reduced the incidence of AAD by 16%. This is encouraging for patients, but future progress on probiotics for AAD and other conditions depends on transparency around strain selection, probiotic design guided by preclinical mechanistic studies, and rigorously conducted human studies.

A Dual Approach by Nanostructured α-Mangostin-Copper Oxide Complexes Against Dental Pathogen Biofilms and Oral Cancer via Apoptosis Gene Modulation.

The development of effective treatments for dental pathogens and oral cancer remains a significant challenge. Copper oxide nanoparticles (CuO NPs) are recognized for their strong antimicrobial properties, attributed to the synthesis of oxygen-dependent radicals. α-Mangostin (MG), a natural xanthone from mangosteen fruit, is well-known for its antioxidant, antimicrobial, and anticancer potential. Antioxidant activity was assessed using superoxide anion and hydroxyl radical anion. The anticancer potential was evaluated by examining apoptosis induction in oral cancer cell lines, focusing on the expression of key apoptotic markers such as Caspase-3, Caspase-8, and FasL. Molecular docking simulations were performed to understand the interaction between MG and biofilm receptors. The CuO-MG NPs evidenced significant antimicrobial efficacy against all tested oral pathogens, with enhanced efficacy attributed to the combined effects of CuO-induced oxidative stress and the antimicrobial properties of MG. Molecular docking studies revealed strong binding affinities of MG to key biofilm receptors, disrupting pathogen adhesion and biofilm formation. CuO-MG NPs demonstrate synergistic antimicrobial, antioxidant, and anticancer properties, offering a potential approach for the management of oral infections and oral cancer. Further preclinical and clinical studies are recommended to ensure their safety and stability in medical applications.

Gut microbiota in gastrointestinal diseases: Insights and therapeutic strategies

Considering the bidirectional crosstalk along the gut-liver axis, gut-derived microorganisms and metabolites can be released into the liver, potentially leading to liver injury. In this editorial, we comment on several studies published in the recent issue of the World Journal of Gastroenterology . We focus specifically on the roles of gut microbiota in selected gastrointestinal (GI) diseases that are prevalent, such as inflammatory bowel disease, metabolic dysfunction-associated steatotic liver disease, and hepatitis B virus-related portal hypertension. Over the past few decades, findings from both preclinical and clinical studies have indicated an association between compositional and metabolic changes in the gut microbiota and the pathogenesis of the aforementioned GI disorders. However, studies elucidating the mechanisms underlying the host-microbiota interactions remain limited. The purpose of this editorial is to summarize current findings and provide insights regarding the context-specific roles of gut microbiota. Ultimately, the discovery of microbiome-based biomarkers may facilitate disease diagnosis and the development of personalized medicine.

Pathogenesis of interstitial lung disease in systemic sclerosis.

Interstitial lung disease (ILD) is a frequent important complication of systemic sclerosis (SSc). Factors relevant to aetiopathogenesis of SSc are also central to SSc-ILD. Severity of SSc-ILD is variable but it has a major impact on morbidity and mortality. Factors determining SSc-ILD susceptibility reflect the genetic architecture of SSc and are increasingly being defined. There are aspects linked to immunogenomics and non-immunological genetic factors that may be less conserved and underlie some of the geographical and racial diversity of SSc. These associations may also underlie important links between autoantibody subgroups and patient level risk of SSc-ILD. Examination of blood and tissue samples and observational clinical research together with integrated analysis of in vitro and in vivo preclinical models have elucidated pathogenic mechanisms of SSc-ILD. These have confirmed the potential importance of immune mechanisms in the innate and adaptive immune systemic as well as a significant role for profibrotic pathways especially transforming growth factor beta (TGFbeta) and its regulators and downstream mediators. Recent analysis of clinical trial cohorts as well as integrated and multilevel high dimensional analysis of bio-samples has shed further light on SSc-ILD. This is likely to underpin future advances in stratified and precision medicine for treatment of SSc.

Discovery of ZG-2305, an Orally Bioavailable Factor Inhibiting HIF Inhibitor for the Treatment of Obesity and Fatty Liver Disease.

Genetic loss of the 2-oxoglutarate oxygenase factor inhibiting hypoxia-inducible factor (FIH) enhances both glycolysis and aerobic metabolism. FIH is thus a potential target for adiposity control and improving hepatic steatosis. We describe development of a series of novel, potent, and selective FIH inhibitors that occupy both the FIH catalytic site and a recently defined tyrosine conformational-flip pocket. ZG-2305, with a Ki of 79.6 nM for FIH, manifests 38-fold selectivity over the hypoxia-inducible factor (HIF) prolyl hydroxylase PHD2. Oral administration of ZG-2305 in the western-diet induced obesity mouse model results in improved lipid accumulation and recovery from abnormal body weight/hepatic steatosis. Amelioration of nonalcoholic steatohepatitis (NASH) related pathological phenotypes in the HF-CDAA-diet induced NASH mouse model was observed. Preliminary preclinical studies indicate ZG-2305 has good pharmacokinetic properties and an acceptable safety profile. The results imply ZG-2305 is a promising candidate for treatment of obesity and fatty liver disease.

Synergistic role of prebiotics and probiotics in gut microbiome health: Mechanisms and clinical applications

AbstractPrebiotic and probiotic usage has exploded, with most formulations promoting gastrointestinal and immunological benefits. Prebiotics modulate the gut microbiota, as a result, short‐chain fatty acids are released into the bloodstream. Prebiotics have immunomodulatory properties that reduce inflammation while enhancing immune responses and boosting gut health. The potential of probiotics has shown steady expansion in the digestive system, metabolic balance, and vaginal health. Probiotics offer therapeutic and preventative strategies for a range of human diseases. The in vitro studies suggested the delivery matrix might influence their effects through physicochemical interactions with molecular and cellular structures as well as modifications in cellular expression. Dietary fibers and polyphenols both contribute significantly to human health protection and can ferment in the gut microbiota to create butyrate. This comprehensive review aims to highlight the probiotics and prebiotics, and provide evidence to support their use in preventive and therapeutic medicine. It is anticipated that it will help the clinical and preclinical research to look into the effects of inclusion and processing on their activity in different food delivery formulations. There are potential opportunities needed to enhance immunological and digestive health by comprehending and using the interaction between the gut microbiota and the immune system in our diet.

Geldanamycins: Potent Hsp90 Inhibitors with Significant Potential in Cancer Therapy

Geldanamycin, an ansa-macrolide composed of a rigid benzoquinone ring and an aliphatic ansa-bridge, was isolated from Streptomyces hygroscopicus. Geldanamycin is a potent heat shock protein inhibitor with remarkable antiproliferative activity. However, it shows pronounced hepatotoxicity in animal models and unfavorable pharmacokinetic properties. Four geldanamycin analogs have progressed through various phases of clinical trials, but none have yet completed clinical evaluation or received FDA approval. To enhance the efficacy of these Hsp90 inhibitors, strategies such as prodrug approaches or nanocarrier delivery systems could be employed to minimize systemic and organ toxicity. Furthermore, exploring new drug combinations may help overcome resistance, potentially improving therapeutic outcomes. This review discusses the mechanism of action of geldanamycin, its pharmacokinetic properties, and the various approaches employed to alleviate its toxicity and maximize its clinical efficacy. The main focus is on those derivatives that have progressed to clinical trials or that have shown important in vivo activity in preclinical models.

Acute transcutaneous auricular vagus nerve stimulation modulates presynaptic SV2A density in healthy rat brain: An invivo microPET study.

Vagus nerve stimulation (VNS) is the subject of exploration as an adjunct treatment for neurological disorders such as epilepsy, chronic migraine, pain, and depression. A non-invasive form of VNS is transcutaneous auricular VNS (taVNS). Combining animal models and positron emission tomography (PET) may lead to a better understanding of the elusive mechanisms of taVNS. We evaluated the acute effect of electrical stimulation of the left vagus nerve via the ear on brain synaptic vesicle glycoprotein 2A (SV2A) as a measure of presynaptic density and glucose metabolism in naïve rats. Female Sprague-Dawley rats were imaged with [11C]UCB-J (n = 11) or [18F]fluorodeoxyglucose ([18F]FDG) PET (n = 13) on two separate days, (1) at baseline, and (2) after acute unilateral left taVNS or sham stimulation (30 min). We calculated the regional volume of distribution (VT) for [11C]UCB-J and standard uptake values (SUV) for [18F]FDG. We observed regional reductions of [11C]UCB-J binding in response to taVNS ranging from 36% to 59%. The changes in taVNS compared to baseline were significantly larger than those induced by sham stimulation. The differences were observed bilaterally in the frontal cortex, striatum, and midbrain. The [18F]FDG PET uptake remained unchanged following acute taVNS or sham stimulation compared to baseline values. This proof-of-concept study shows for the first time that acute taVNS for 30 min can modulate invivo synaptic SV2A density in cortical and subcortical regions of healthy rats. Preclinical disease models and PET ligands of different targets can be a powerful combination to assess the therapeutic potential of taVNS.

Proteins and Peptides from Food Sources with Effect on Satiety and Their Role as Anti-Obesity Agents: A Narrative Review.

Obesity, clinically defined as a body mass index (BMI) of 30 kg/m2 or higher, is a medical condition characterized by the excessive accumulation of body fat, which can lead to adverse health consequences. As a global public health issue with an escalating prevalence, controlling appetite and satiety is essential for regulating energy balance and managing body weight. Dietary proteins and peptides have gained interest in their potential to prevent and treat obesity by modulating satiety signals. This narrative review analyzes scientific evidence highlighting the role of dietary proteins and peptides in regulating satiety signals and investigates their therapeutic potential in preventing and treating obesity. A comprehensive literature search was conducted in multiple electronic databases, including PubMed, Scopus, and Web of Science. The search focused on articles examining the impact of dietary proteins and peptides on satiety and obesity, encompassing both preclinical and clinical trials. Several studies have demonstrated a correlation between the intake of specific proteins or peptides from plant and animal sources and satiety regulation. These investigations identified mechanisms where amino acids and peptides interact with enteroendocrine cell receptors, activating intracellular signaling cascades that promote the release of anorexigenic gut hormones such as cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1), and peptide YY (PYY). Both in vitro and in vivo assays have shown that these interactions contribute to appetite regulation and the sensation of satiety. Using proteins and peptides in the diet may be an effective strategy for regulating appetite and controlling body weight. However, more research-including clinical trials-is needed to understand the underlying mechanisms better and optimize the application of these bioactive compounds in preventing and treating obesity.

Sweeten the pill: Multi-faceted polysaccharide-based carriers for colorectal cancer treatment

Colorectal cancer (CRC) ranks as the second deadliest cancer globally and the third most common malignant tumor. While surgery remains the primary treatment for CRC, alternative therapies such as chemotherapy, molecular targeted therapy, and immunotherapy are also commonly used. The significant side effects and toxicity of conventional drugs drive the search for novel targeted therapies, including the design of advanced drug delivery systems. Polysaccharide-based biopolymers, with their low toxicity, non-immunogenic behavior, synergistic interactions with other biopolymers, and tissue and cell compatibility, emerge as excellent drug carriers for this application. This review aims to provide an in-depth overview of recent advancements in developing polysaccharide-based biopolymeric carriers for anticancer compounds in the treatment of CRC. We highlight the multifunctional nature of polysaccharides, showcasing their potential as standalone drug carriers or as integral components of intelligent robotic devices for biomedical therapeutic applications. In addition to exploring the opportunities for using carbohydrate polymers in CRC treatment, we address the challenges and failures that may limit their applicability in biomedical research, as well as summarize the recent preclinical and clinical trials, resulting in several commercialization attempts. This comprehensive overview critically summarizes the potential of polysaccharide-based biomaterials in CRC treatment.

QM107, a novel CD148 (RTP Type J) activating peptide therapy for treating neovascular age-related macular degeneration.

Angiogenesis is a pathological component of neovascular age-related macular degeneration. Current therapies, although successful, are prone to high levels of patient non-response and a loss of efficacy over time, indicating the need to explore other therapeutic avenues. We have shown that an interaction between syndecan-2 and the tyrosine phosphatase receptor CD148 (RTP Type J) results in the ablation of angiogenesis. Here we exploit this pathway to develop a peptide activator of CD148 as a therapy for neovascular age-related macular degeneration. We tested a peptide (QM107) derived from syndecan-2 in a variety of angiogenesis models and a pre-clinical model of neovascular age-related macular degeneration. We assessed the toxicological and inflammatory profiles of QM107 and its stability in vitreous humour. QM107 inhibits angiogenesis in ex vivo sprouting assays and disrupts endothelial microcapillary formation via inhibition of cell migration. QM107 acts through CD148, leading to changes in GSK3A phosphorylation and β1 integrin activation. QM107 elicits a negligible inflammatory response and exhibits limited toxicity in cultured cells, and is stable in vitreous humour. Finally, we show proof of concept that QM107 blocks angiogenesis in vivo using a model of neovascular age-related macular degeneration. We have developed a CD148 activating peptide which shows promise in inhibiting angiogenesis in models of neovascular age-related macular degeneration. This treatment could either represent an alternative or augment existing therapies, and owing to its distinct mode of action be used in patients who do not respond to existing treatments.

Valencene as a novel potential downregulator of THRB in NSCLC: network pharmacology, molecular docking, molecular dynamics simulation, ADMET analysis, and in vitro analysis.

This study investigates the molecular targets and pathways affected by valencene in non-small cell lung cancer (NSCLC) through network pharmacology and in vitro assays. Valencene's chemical structure was sourced from PubChem, and target identification utilized the PharmMapper database, cross-referenced with UniProtKB for official gene symbols. NSCLC-associated targets were identified via GeneCards, followed by protein-protein interaction analysis using STRING. Molecular docking studies employed AutoDock Vina to assess binding interactions with key nuclear receptors (RXRA, RXRB, RARA, RARB, THRB). Molecular dynamics simulations were conducted in GROMACS over 200ns, while ADME/T properties were evaluated using Protox. In vitro assays measured cell viability in A549 and HEL 299 cells via MTT assays, assessed apoptosis through Hoechst staining, and evaluated mitochondrial potential with JC-1. Molecular docking revealed strong binding affinities of valencene (below - 5kcal/mol) to nuclear receptors, outperforming 5-fluorouracil (5-FU). Molecular dynamics simulations indicated robust structural stability of the THRB-valencene complex, with favorable interaction energies. Notably, valencene exhibited a selectivity index of 2.293, higher than 5-FU's 2.231, suggesting enhanced safety for normal cells (HEL 299). Fluorescence microscopy confirmed dose-dependent DNA fragmentation and decreased mitochondrial membrane potential. These findings underscore valencene's potential as an effective therapeutic agent for lung cancer, demonstrating an IC50 of 16.71μg/ml in A549 cells compared to 5-FU's 12.7μg/ml, warranting further investigation in preclinical models and eventual clinical trials.

A Novel Hydrogel Sponge for Three-Dimensional Cell Culture

Background/Objectives: Three-dimensional (3D) cell culture technologies allow us to overcome the constraints of two-dimensional methods in different fields like biochemistry and cell biology and in pharmaceutical in vitro tests. In this study, a novel 3D hydrogel sponge scaffold, composed of a crosslinked polyacrylic acid forming a porous matrix, has been developed and characterized. Methods: The scaffold was obtained via an innovative procedure involving thermal treatment followed by a salt-leaching step on a matrix-containing polymer along with a gas-forming agent. Based on experimental design for mixtures, a series of formulations were prepared to study the effect of the three components (polyacrylic acid, NaHCO3 and NaCl) on the scaffold mechanical properties, density, swelling behavior and morphological changes. Physical appearance, surface morphology, porosity, molecular diffusion, transparency, biocompatibility and cytocompatibility were also evaluated. Results: The hydrogel scaffolds obtained show high porosity and good optical transparency and mechanical resistance. The scaffolds were successfully employed to culture several cell lines for more than 20 days. Conclusions: The developed scaffolds could be an important tool, as such or with a specific coating, to obtain a more predictive cellular response to evaluate drugs in preclinical studies or for testing chemical compounds, biocides and cosmetics, thus reducing animal testing.

Expression of c-erb-B2 oncoprotein as a neoantigen strategy to repurpose anti-neu antibody therapy in a model of melanoma.

In this study, we tested a novel approach of "repurposing" a biomarker typically associated with breast cancer for use in melanoma. HER2/neu is a well characterized biomarker in breast cancer for which effective anti-HER2/neu therapies are readily available. We constructed a lentivirus encoding c-erb-B2, an animal (rat) homolog to HER2/neu. This was used to transfect B16 melanoma in vitro for use in an orthotopic preclinical mouse model, which resulted in expression of rat c-erb-B2 as a neoantigen target for anti-c-erb-B2 monoclonal antibody (7.16.4). The c-erb-B2-expressing melanoma was designated B16/neu. 7.16.4 produced statistically significant in vivo anti-tumor responses against B16/neu. This effect was mediated by NK-cell antibody-dependent cell-mediated cytotoxicity. To further model human melanoma (which expresses < 5% HER2/neu), our c-erb-B2 encoding lentivirus was used to inoculate naïve (wild-type) B16 tumors in vivo, resulting in successful c-erb-B2 expression. When combined with 7.16.4, anti-tumor responses were again demonstrated where approximately 40% of mice treated with c-erb-B2 lentivirus and 7.16.4 achieved complete clinical response and long-term survival. For the first time, we demonstrated a novel strategy to repurpose c-erb-B2 as a neoantigen target for melanoma. Our findings are particularly significant in the contemporary setting where newer anti-HER2/neu antibody-drug therapies have shown increased efficacy.