Oncolytic effects of the recombinant Newcastle disease virus, rAF-IL12, against colon cancer cells in vitro and in tumor-challenged NCr-Foxn1nu nude mice

Interleukin-12 Delivery Strategies and Advances in Tumor Immunotherapy

Interleukin-12 (IL-12) is considered to be a promising cytokine for enhancing an antitumor immune response; however, recombinant IL-12 has shown significant toxicity and limited efficacy in early clinical trials. Recently, many strategies for delivering IL-12 to tumor tissues have been developed, such as modifying IL-12, utilizing viral vectors, non-viral vectors, and cellular vectors. Previous studies have found that the fusion of IL-12 with extracellular matrix proteins, collagen, and immune factors is a way to enhance its therapeutic potential. In addition, studies have demonstrated that viral vectors are a good platform, and a variety of viruses such as oncolytic viruses, adenoviruses, and poxviruses have been used to deliver IL-12-with testing previously conducted in various cancer models. The local expression of IL-12 in tumors based on viral delivery avoids systemic toxicity while inducing effective antitumor immunity and acting synergistically with other therapies without compromising safety. In addition, lipid nanoparticles are currently considered to be the most mature drug delivery system. Moreover, cells are also considered to be drug carriers because they can effectively deliver therapeutic substances to tumors. In this article, we will systematically discuss the anti-tumor effects of IL-12 on its own or in combination with other therapies based on different delivery strategies.

Simultaneous Expression of Different Therapeutic Genes by Infection with Multiple Oncolytic HSV-1 Vectors

Oncolytic viruses (OVs) are anti-cancer therapeutics combining the selective killing of cancer cells with the triggering of an anti-tumoral immune response. The latter effect can be improved by arming OVs with immunomodulatory factors. Due to the heterogeneity of cancer and the tumor microenvironment, it is anticipated that strategies based on the co-expression of multiple therapeutic molecules that interfere with different features of the target malignancy will be more effective than mono-therapies. Here, we show that (i) the simultaneous expression of different proteins in triple-negative breast cancer (TNBC) cells can be achieved through their infection with a combination of OVs based on herpes simplex virus type 1 (oHSV1), each encoding a single transgene. (ii) The level of expressed proteins is dependent on the number of infectious viral particles utilized to challenge tumor cells. (iii) All recombinant viruses exhibited comparable efficacy in the killing of TNBC cells in single and multiple infections and showed similar kinetics of replication. Overall, our results suggest that a strategy based on co-infection with a panel of oHSV1s may represent a promising combinatorial therapeutic approach for TNBC, as well as for other types of solid tumors, that merits further investigation in more advanced in vitro and in vivo models.

Newcastle Disease Virus Virotherapy: Unveiling Oncolytic Efficacy and Immunomodulation

In virotherapy, cancer cells are eradicated via viral infection, replication, and dissemination (oncolysis).

BACKGROUND

This study aims to evaluate the oncolytic potential of Newcastle disease virus (NDV) against colon cancer and explore the immune response associated with its therapeutic effects.

METHODS

NDV was tested for its oncolytic potential in colon cancer cell lines using MTT assays and apoptosis assessments. Tumor-induced mice were treated with NDV, tumor cell lysate (TCL), or a combination of both. After the euthanasia of murine subjects, an assessment of oncolytic efficacy was performed through flow cytometry analysis of murine blood and tumor tissue, targeting CD83, CD86, CD8, and CD4. An ELISA was also performed to examine interferon-gamma levels, interleukin-4 levels, interleukin-12 levels, and interleukin-10 levels in serum and spleen homogenate.

RESULTS

Cell viability was low in HCT116 and HT-29, indicating a cytotoxic effect in the MTT assay. NDV+TCL recorded the highest rate of cell death (56.72%). NDV+TCL had accelerated cell death after 48 h, reaching 58.4%. The flow cytometry analysis of the blood and tumor of mice with induced tumor treated with combined treatment revealed elevated levels of CD83, CD86, CD8, and CD4 (76.3, 66.9, 83.7, and 14.4%, respectively). The ELISA levels of IFN-γ, IL-4, and IL-12 in serum and the spleen homogenate were elevated (107.6 ± 9.25 pg/mL). In contrast, the expression of IL-10 was significantly reduced (1 ± 0.79).

The Application of Newcastle Disease Virus (NDV): Vaccine Vectors and Tumor Therapy

Newcastle disease virus (NDV) is an avian pathogen with an unsegmented negative-strand RNA genome that belongs to the Paramyxoviridae family. While primarily pathogenic in birds, NDV presents no threat to human health, rendering it a safe candidate for various biomedical applications. Extensive research has highlighted the potential of NDV as a vector for vaccine development and gene therapy, owing to its transcriptional modularity, low recombination rate, and lack of a DNA phase during replication. Furthermore, NDV exhibits oncolytic capabilities, efficiently eliciting antitumor immune responses, thereby positioning it as a promising therapeutic agent for cancer treatment. This article comprehensively reviews the biological characteristics of NDV, elucidates the molecular mechanisms underlying its oncolytic properties, and discusses its applications in the fields of vaccine vector development and tumor therapy.

Synergistic effects of Bacillus coagulans and Newcastle disease virus on human colorectal adenocarcinoma cell proliferation

Background and Objectives

Colorectal cancer (CRC) is a common type of cancer that has a high death rate and is becoming more common in developed countries. Currently, there are several treatment options available for CRC patients, and clinical trials are being conducted to improve conventional therapies. This study investigates the combined impact of Bacillus coagulans (B.C) and Newcastle disease virus (NDV) on the growth of human colorectal adenocarcinoma cells (HT29 cell line).

Materials and Methods

The HT29 cell line was cultured under controlled laboratory conditions. They were treated with Fluorouracil (5-FU), NDV, and B.C., after which various assessments were conducted to determine the effects of these treatments. These assessments included MTT assay for cytotoxicity, evaluation of cell viability, and measurement of caspase 8 and 9 activity levels. The significance of the data was determined at a threshold of P<0.05 following analysis.

Results

The usage of NDV and B.C significantly increased cell death and reduced cell growth in the HT29 cell line, when compared to the control group. Moreover, the combined application of NDV and B.C along with 5-FU exhibited a synergistic effect in decreasing the proliferation of HT29 cells. Additionally, the results indicated that intrinsic apoptosis pathway was activated by B.C and NDV.

Conclusion

It appears that utilizing oncolytic viruses (OV) and bacteria in conjunction with chemotherapy drugs could potentially aid in reducing the growth of colorectal cancer cells. However, further research is necessary, including animal studies, to confirm the efficacy of this treatment method.

The tumor suppressive effect and apoptotic mechanism of TRAIL gene-containing recombinant NDV in TRAIL-resistant colorectal cancer HT-29 cells and TRAIL-nonresistant HCT116 cells, with each cell bearing a mouse model

BACKGROUND

TRAIL is an anticancer drug that induces cancer cell apoptosis by interacting with death receptors (DRs). However, owing to low cell-surface expression of DRs, certain colorectal cancer (CRC) cells resist TRAIL-induced apoptosis. Newcastle disease virus (NDV) infection can elevate DR protein expression in cancer cells, potentially influencing their TRAIL sensitivity. However, the precise mechanism by which NDV infection modulates DR expression and impacts TRAIL sensitivity in cancer cells remains unknown.

METHODS

Herein, we developed nonpathogenic NDV VG/GA strain-based recombinant NDV (rNDV) and TRAIL gene-containing rNDV (rNDV-TRAIL). We observed that viral infections lead to increased DR and TRAIL expressions and activate signaling proteins involved in intrinsic and extrinsic apoptosis pathways. Experiments were conducted in vitro using TRAIL-resistant CRC cells (HT-29) and nonresistant CRC cells (HCT116) and in vivo using relevant mouse models.

RESULTS

rNDV-TRAIL was found to exhibit better apoptotic efficacy than rNDV in CRC cells. Notably, rNDV-TRAIL had the stronger cancer cell-killing effect in TRAIL-resistant CRC cells. Western blot analyses showed that both rNDV and rNDV-TRAIL infections activate signaling proteins involved in the intrinsic and extrinsic apoptotic pathways. Notably, rNDV-TRAIL promotes concurrent intrinsic and extrinsic signal transduction in both HCT-116 and HT-29 cells.

CONCLUSIONS

Therefore, rNDV-TRAIL infection effectively enhances DR expression in DR-depressed HT-29 cells. Moreover, the TRAIL protein expressed by rNDV-TRAIL effectively interacts with DR, leading to enhanced apoptosis in TRAIL-resistant HT-29 cells. Therefore, rNDV-TRAIL has potential as a promising therapeutic approach for treating TRAIL-resistant cancers.

Developing Oncolytic Viruses for the Treatment of Cervical Cancer

Cervical cancer represents one of the most important malignancies among women worldwide. Current therapeutic approaches for cervical cancer are reported not only to be inadequate for metastatic cervical cancer, but are also considered as cytotoxic for several patients leading to serious side effects, which can have negative implications on the quality of life of women. Therefore, there is an urgent need for the development of innovative and effective treatment options. Oncolytic viruses can eventually become effective biological agents, since they preferentially infect and kill cancer cells, while leaving the normal tissue unaffected. Moreover, they are also able to leverage the host immune system response to limit tumor growth. This review aims to systematically describe and discuss the different types of oncolytic viruses generated for targeting cervical cancer cells, as well as the outcome of the combination of virotherapy with conventional therapies. Although many preclinical studies have evaluated the therapeutic efficacy of oncolytic viruses in cervical cancer, the number of clinical trials so far is limited, while their oncolytic properties are currently being tested in clinical trials for the treatment of other malignancies.

Immune responses elicited by ssRNA(-) oncolytic viruses in the host and in the tumor microenvironment

Oncolytic viruses (OVs) are at the forefront of biologicals for cancer treatment. They represent a diverse landscape of naturally occurring viral strains and genetically modified viruses that, either as single agents or as part of combination therapies, are being evaluated in preclinical and clinical settings. As the field gains momentum, the research on OVs has been shifting efforts to expand our understanding of the complex interplay between the virus, the tumor and the immune system, with the aim of rationally designing more efficient therapeutic interventions. Nowadays, the potential of an OV platform is no longer defined exclusively by the targeted replication and cancer cell killing capacities of the virus, but by its contribution as an immunostimulator, triggering the transformation of the immunosuppressive tumor microenvironment (TME) into a place where innate and adaptive immunity players can efficiently engage and lead the development of tumor-specific long-term memory responses. Here we review the immune mechanisms and host responses induced by ssRNA(-) (negative-sense single-stranded RNA) viruses as OV platforms. We focus on two ssRNA(-) OV candidates: Newcastle disease virus (NDV), an avian paramyxovirus with one of the longest histories of utilization as an OV, and influenza A (IAV) virus, a well-characterized human pathogen with extraordinary immunostimulatory capacities that is steadily advancing as an OV candidate through the development of recombinant IAV attenuated platforms.

Chimeric Newcastle Disease Virus Vectors Expressing Human IFN-γ Mediate Target Immune Responses and Enable Multifaceted Treatments

The therapeutic potential of Newcastle disease virus (NDV) has been reported as both an oncolytic agent and a vaccine vector against many antigens. However, in the individuals already immunized with NDVs, second and subsequent administration does not provide substantial benefits. In this study, two types of recombinant chimeric NDVs using APMV-2 F and HN genes were generated. In rNDV-2HN, the wild-type NDV HN gene was replaced with the APMV-2 HN gene, and in rNDV-2F/2HN, both wild-type F and HN genes were replaced with APMV-2 F and HN genes, respectively. We enhanced the immune responses of these chimeric viruses by inserting the human IFN-γ gene. To examine the escape from NDV antiserum, each virus was treated with diluted NDV antiserum, and HEp-2 cells were infected with these virus particles. The two constructed chimeric viruses indicated notably lower virus-neutralizing titer compared to wild-type NDV and escaped the action of NDV antiserum. These two chimeric viruses infected both respiratory and colon cancer cell lines, indicating their potential as a cancer treatment tool. Chimeric viruses with enhanced immune responses can be considered a novel therapeutic strategy in cancer treatment that can be administered multiple times and used to enhance immune cells interaction.

Development of Molecular Mechanisms and Their Application on Oncolytic Newcastle Disease Virus in Cancer Therapy

Cancer is caused by the destruction or mutation of cellular genetic materials induced by environmental or genetic factors. It is defined by uncontrolled cell proliferation and abnormality of the apoptotic pathways. The majority of human malignancies are characterized by distant metastasis and dissemination. Currently, the most common means of cancer treatment include surgery, radiotherapy, and chemotherapy, which usually damage healthy cells and cause toxicity in patients. Targeted therapy is an effective tumor treatment method with few side effects. At present, some targeted therapeutic drugs have achieved encouraging results in clinical studies, but finding an effective solution to improve the targeting and delivery efficiency of these drugs remains a challenge. In recent years, oncolytic viruses (OVs) have been used to direct the tumor-targeted therapy or immunotherapy. Newcastle disease virus (NDV) is a solid oncolytic agent capable of directly killing tumor cells and increasing tumor antigen exposure. Simultaneously, NDV can trigger the proliferation of tumor-specific immune cells and thus improve the therapeutic efficacy of NDV in cancer. Based on NDV’s inherent oncolytic activity and the stimulation of antitumor immune responses, the combination of NDV and other tumor therapy approaches can improve the antitumor efficacy while reducing drug toxicity, indicating a broad application potential. We discussed the biological properties of NDV, the antitumor molecular mechanisms of oncolytic NDV, and its application in the field of tumor therapy in this review. Furthermore, we presented new insights into the challenges that NDV will confront and suggestions for increasing NDV’s therapeutic efficacy in cancer.

Viruses as tools in gene therapy, vaccine development, and cancer treatment

Using viruses to our advantage has been a huge leap for humanity. Their ability to mediate horizontal gene transfer has made them useful tools for gene therapy, vaccine development, and cancer treatment. Adenoviruses, adeno-associated viruses, retroviruses, lentiviruses, alphaviruses, and herpesviruses are a few of the most common candidates for use as therapeutic agents or efficient gene delivery systems. Efforts are being made to improve and perfect viral-vector-based therapies to overcome potential or reported drawbacks. Some preclinical trials of viral vector vaccines have yielded positive results, indicating their potential as prophylactic or therapeutic vaccine candidates. Utilization of the oncolytic activity of viruses is the future of cancer therapy, as patients will then be free from the harmful effects of chemo- or radiotherapy. This review discusses in vitro and in vivo studies showing the brilliant therapeutic potential of viruses.

Oncolytic Activity of Wild-type Newcastle Disease Virus HK84 Against Hepatocellular Carcinoma Associated with Activation of Type I Interferon Signaling

BACKGROUND AND AIMS

Hepatocellular carcinoma (HCC) is listed as one of the most common causes of cancer-related death. Oncolytic therapy has become a promising treatment because of novel immunotherapies and gene editing technology, but biosafety concerns remain the biggest limitation for clinical application. We studied the the antitumor activity and biosafety of the wild-type Newcastle disease virus HK84 strain (NDV/HK84) and 10 other NDV strains.

METHODS

Cell proliferation and apoptosis were determined by cell counting Kit-8 and fluorescein isothiocyanate Annexin V apoptosis assays. Colony formation, wound healing, and a xenograft mouse model were used to evaluate in vivo and in vitro oncolytic effectiveness. The safety of NDV/HK84 was tested in nude mice by an in vivo luciferase imaging system. The replication kinetics of NDV/HK84 in normal tissues and tumors were evaluated by infectious-dose assays in eggs. RNA sequencing analysis was performed to explore NDV/HK84 activity and was validated by quantitative real-time PCR.

RESULTS

The cell counting Kit-8 assays of viability found that the oncolytic activity of the NDV strains differed with the multiplicity of infection (MOI). At an MOI of 20, the oncolytic activity of all NDV strains except the DK/JX/21358/08 strain was >80%. The oncolytic activities of the NDV/HK84 and DK/JX/8224/04 strains were >80% at both MOI=20 and MOI=2. Only NDV/HK84 had >80% oncolytic activities at both MOI=20 and MOI=2. We chose NDV/HK84 as the candidate virus to test the oncolytic effect of NDV in HCC in the in vitro and in vivo experiments. NDV/HK84 killed human SK-HEP-1 HCC cells without affecting healthy cells.

CONCLUSIONS

Intratumor infection with NDV/HK84 strains compared with vehicle controls or positive controls indicated that NDV/HK84 strain specifically inhibited HCC without affecting healthy mice. High-throughput RNA sequencing showed that the oncolytic activity of NDV/HK84 was dependent on the activation of type I interferon signaling.

Advances in the Study of Antitumour Immunotherapy for Newcastle Disease Virus

This article reviews the preclinical research, clinical application and development of Newcastle disease virus (NDV) in the field of cancer therapy. Based on the distinctive antitumour properties of NDV and its positive interaction with the patient's immune system, this biologic could be considered a major breakthrough in cancer treatment. On one hand, NDV infection creates an inflammatory environment in the tumour microenvironment, which can directly activate NK cells, monocytes, macrophages and dendritic cells and promote the recruitment of immune cells. On the other hand, NDV can induce the upregulation of immune checkpoint molecules, which may break immune tolerance and immune checkpoint blockade resistance. In fact, clinical data have shown that NDV combined with immune checkpoint blockade can effectively enhance the antitumour response, leading to the regression of local tumours and distant tumours when injected, and this effect is further enhanced by targeted manipulation and modification of the NDV genome. At present, recombinant NDV and recombinant NDV combined with immune checkpoint blockers have entered different stages of clinical trials. Based on these studies, further research on NDV is warranted.