Golden Syrian Hamster Models for Cancer Research

Coxsackievirus B3 HFMD animal models in Syrian hamster and rhesus monkey

Coxsackievirus B3 (CVB3) is the pathogen causing hand, foot and mouth disease (HFMD), which manifests across a spectrum of clinical severity from mild to severe. However, CVB3-infected mouse models mainly demonstrate viral myocarditis and pancreatitis, failing to replicate human HFMD symptoms. Although several enteroviruses have been evaluated in Syrian hamsters and rhesus monkeys, there is no comprehensive data on CVB3. In this study, we have first tested the susceptibility of Syrian hamsters to CVB3 infection via different routes. The results showed that Syrian hamsters were successfully infected with CVB3 by intraperitoneal injection or nasal drip, leading to nasopharyngeal colonization, acute severe pathological injury, and typical HFMD symptoms. Notably, the nasal drip group exhibited a longer viral excretion cycle and more severe pathological damage. In the subsequent study, rhesus monkeys infected with CVB3 through nasal drips also presented signs of HFMD symptoms, viral excretion, serum antibody conversion, viral nucleic acids and antigens, and the specific organ damages, particularly in the heart. Surprisingly, there were no significant differences in myocardial enzyme levels, and the clinical symptoms resembled those often associated with common, mild infections. In summary, the study successfully developed severe Syrian hamsters and mild rhesus monkey models for CVB3-induced HFMD. These models could serve as a basis for understanding the disease pathogenesis, conducting pre-trial prevention and evaluation, and implementing post-exposure intervention.

Is placental glutathione S-Transferase (GST-P) a suitable biomarker for oral carcinogenesis: A scoping review

Placental Glutathione S-Transferase (GST-P) can be considered a useful marker of not only of preneoplastic lesion in rat hepatocarcinogenesis and hamster pancreatic carcinogen but also as a potential marker for premalignant and malignant lesions in cases of buccal pouch mucosa. In this context, the aim of this review is to elucidate the following question whether the GST-P is a suitable biomarker for oral carcinogenesis. A total of 16 studies were carefully selected. Our results demonstrate that GST-P expression is a useful and coherent marker for oral carcinogenesis. Regarding the samples, most studies evaluated hamsters, two evaluated GST-P expression in rats and three evaluated GST-P expression in human cells. All studies demonstrated positive findings allowing us to consider such studies reliable. In summary, our conclusion is that GST-P can be a suitable biomarker for oral carcinogenesis.

Exploring animal models in oral cancer research and clinical intervention: A critical review

Cancer is a leading cause of death worldwide, but advances in treatment, early detection, and prevention have helped to reduce its impact. To translate cancer research findings into clinical interventions for patients, appropriate animal experimental models, particularly in oral cancer therapy, can be helpful. In vitro experiments using animal or human cells can provide insight into cancer's biochemical pathways. This review discusses the various animal models used in recent years for research and clinical intervention in oral cancer, along with their advantages and disadvantages. We highlight the advantages and limitations of the used animal models in oral cancer research and therapy by searching the terms of animal models, oral cancer, oral cancer therapy, oral cancer research, and animals to find all relevant publications during 2010-2023. Mouse models, widely used in cancer research, can help us understand protein and gene functions in vivo and molecular pathways more deeply. To induce cancer in rodents, xenografts are often used, but companion animals with spontaneous tumours are underutilized for rapid advancement in human and veterinary cancer treatments. Like humans with cancer, companion animals exhibit biological behaviour, treatment responses, and cytotoxic agent responses similar to humans. In companion animal models, disease progression is more rapid, and the animals have a shorter lifespan. Animal models allow researchers to study how immune cells interact with cancer cells and how they can be targeted specifically. Additionally, animal models have been extensively used in research on oral cancers, so researchers can use existing knowledge and tools to better understand oral cancers using animal models.

Enhancement in the Therapeutic Efficacy of In Vivo BNCT Mediated by GB-10 with Electroporation in a Model of Oral Cancer

Boron neutron capture therapy (BNCT) combines preferential tumor uptake of ¹⁰B compounds and neutron irradiation. Electroporation induces an increase in the permeability of the cell membrane. We previously demonstrated the optimization of boron biodistribution and microdistribution employing electroporation (EP) and decahydrodecaborate (GB-10) as the boron carrier in a hamster cheek pouch oral cancer model. The aim of the present study was to evaluate if EP could improve tumor control without enhancing the radiotoxicity of BNCT in vivo mediated by GB-10 with EP 10 min after GB-10 administration. Following cancerization, tumor-bearing hamster cheek pouches were treated with GB-10/BNCT or GB-10/BNCT + EP. Irradiations were carried out at the RA-3 Reactor. The tumor response and degree of mucositis in precancerous tissue surrounding tumors were evaluated for one month post-BNCT. The overall tumor response (partial remission (PR) + complete remission (CR)) increased significantly for protocol GB-10/BNCT + EP (92%) vs. GB-10/BNCT (48%). A statistically significant increase in the CR was observed for protocol GB-10/BNCT + EP (46%) vs. GB-10/BNCT (6%). For both protocols, the radiotoxicity (mucositis) was reversible and slight/moderate. Based on these results, we concluded that electroporation improved the therapeutic efficacy of GB-10/BNCT in vivo in the hamster cheek pouch oral cancer model without increasing the radiotoxicity.

Syrian hamster as an ideal animal model for evaluation of cancer immunotherapy

Cancer immunotherapy (CIT) has emerged as an exciting new pillar of cancer treatment. Although benefits have been achieved in individual patients, the overall response rate is still not satisfactory. To address this, an ideal preclinical animal model for evaluating CIT is urgently needed. Syrian hamsters present similar features to humans with regard to their anatomy, physiology, and pathology. Notably, the histological features and pathological progression of tumors and the complexity of the tumor microenvironment are equivalent to the human scenario. This article reviews the current tumor models in Syrian hamster and the latest progress in their application to development of tumor treatments including immune checkpoint inhibitors, cytokines, adoptive cell therapy, cancer vaccines, and oncolytic viruses. This progress strongly advocates Syrian hamster as an ideal animal model for development and assessment of CIT for human cancer treatments. Additionally, the challenges of the Syrian hamster as an animal model for CIT are also discussed.

Development of a Syrian hamster anti-PD-L1 monoclonal antibody enables oncolytic adenoviral immunotherapy modelling in an immunocompetent virus replication permissive setting

Introduction

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of cancer, but preclinical testing of hypotheses such as combination therapies has been complicated, in part due to species incompatibility issues. For example, one of few known permissive animal models for oncolytic adenoviruses is the Syrian hamster, for which an ICI, mainly an anti-PD-L1 monoclonal antibody (mAb) was not previously available. In this study, we developed an anti-Syrian hamster PD-L1 mAb to enable the evaluation of safety and efficacy, when combining anti-PD-L1 with an oncolytic adenovirus encoding tumour necrosis factor alpha (TNFα) and interleukin-2 (IL-2) (Ad5/3-E2F-D24-hTNFα-IRES-hIL-2 or TILT-123).

Methods

Recombinant Syrian hamster PD-L1 was expressed and mice immunized for mAb formation using hybridoma technology. Clonal selection through binding and functional studies in vitro, in silico and in vivo identified anti-PD-L1 clone 11B12-1 as the primary mAb candidate for immunotherapy modelling. The oncolytic virus (OV) and ICI combination approach was then evaluated using 11B12-1 and TILT-123 in a Syrian hamster model of pancreatic ductal adenocarcinoma (PDAC).

Results

Supernatants from hybridoma parent subclone 11B12B4 provided the highest positive PD-L1 signal, on Syrian hamster PBMCs and three cancer cell lines (HT100, HapT1 and HCPC1). In vitro co-cultures revealed superior immune modulated profiles of cell line matched HT100 tumour infiltrating lymphocytes when using subclones of 7G2, 11B12 and 12F1. Epitope binning and epitope prediction using AlphaFold2 and ColabFold revealed two distinct functional epitopes for clone 11B12-1 and 12F1-1. Treatment of Syrian hamsters bearing HapT1 tumours, with 11B12-1 induced significantly better (p<0.05) tumour growth control than isotype control by day 12. 12F1-1 did not induce significant tumour growth control. The combination of 11B12-1 with oncolytic adenovirus TILT-123 improved tumour growth control further, when compared to monotherapy (p<0.05) by day 26.

Conclusions

Novel Syrian hamster anti-PD-L1 clone 11B12-1 induces tumour growth control in a hamster model of PDAC. Combining 11B12-1 with oncolytic adenovirus TILT-123 improves tumour growth control further and demonstrates good safety and toxicity profiles.