Low-Intensity Ultrasound as a Novel Strategy to Improve the Cytotoxic Effect of Oncolytic Reovirus on Colorectal Cancer Model Cells.

BACKGROUND: Colorectal cancer is the third most common cancer all over the world, so in the battle to fight this hurdle, new therapeutic approaches such as oncolytic viruses (OV) have attracted much attention because of the fact that they can inherently kill cancer cells. Oncolytic reovirus is one of the candidates for treatment as a nonpathogenic species specially reovirus type 3 Dearing (T3D), which can induce apoptosis. To speed up the entry and function of the reovirus, low-intensity ultrasound, which is a safe system for damage to the cells and tissues, is a promising approach to be used in combination with other therapeutic approach. METHODS: L929 and CT26 cells were infected with reovirus T3D and were exposed to ultrasonic irradiation (1 MHz, 1 W/cm2, and 20% duty factor) for 10 s. The viruses' titer level of both groups was calculated in 2 types of cells by using the CCID50 method and compared with each other. Apoptosis, after 24 h, was measured by the flow cytometry method. RESULT: The results of CCID50 in infected cells were exposed to low-intensity ultrasound showed an increased virus titer compared with unexposed infected cells. Moreover, according to the results of the flow cytometry test, it was found that the amount of apoptosis in infected cells that are exposed to low-intensity ultrasound waves is higher than those infected cells. CONCLUSION: Due to the results of CCID50 and flow cytometry tests, low-intensity ultrasound increases the cytotoxicity level of reovirus in CT26 cells of the cellular colorectal cancer model.

Combination therapy using human papillomavirus L1/E6/E7 genes and archaeosome: a nanovaccine confer immuneadjuvanting effects to fight cervical cancer.

Cancer is a leading cause of death worldwide. Cervical cancer caused by human papillomavirus (HPV) is a major health problem in women. DNA vaccines are a perfect approach to immunization, but their potency in clinical trials has been insufficient for generating effective immunity, which may be related to the degradation of the DNA via nucleases, poor delivery to antigen-presenting cells (APCs), and insufficient uptake of DNA plasmids by cells upon injection. Archaeosome is a nano-delivery systems based on liposomes with their immunological role have been developed for gene delivery. In this study, human papillomavirus type 16 genes, containing truncated L1, E6, and E7, were simultaneously used in combination therapy with archaeosome and assessed in vivo. Findings supported that archaeosomes promotes immune responses to DNA vaccines and a long-term CTL response was generated with a low antigen dose. Combination therapy with archaeosome/L1/E6/E7 vaccines exhibited a strong cytolytic activity against tumor cells and induced prophylactic and therapeutic effect against the development of tumor in the animal model.

Kinetics of Oncolytic Reovirus T3D Replication and Growth Pattern in Mesenchymal Stem Cells.

OBJECTIVE: Currently, application of oncolytic-virus in cancer treatment of clinical trials are growing. Oncolytic-reovirus is an attractive anti-cancer therapeutic agent for clinical testing. Many studies used mesenchymal stem cells (MSCs) as a carrier cell to enhance the delivery and quality of treatment with oncolytic-virotherapy. But, biosynthetic capacity and behavior of cells in response to viral infections are different. The infecting process of reoviruses takes from two-hours to one-week, depends on host cell and the duration of different stages of virus replication cycle. The latter includes the binding of virus particle, entry, uncoating, assembly and release of progeny-viruses. We evaluated the timing and infection cycle of reovirus type-3 strain Dearing (T3D), using one-step replication experiment by molecular and conventional methods in MSCs and L929 cell as control. MATERIALS AND METHODS: In this experimental study, L929 and adipose-derived MSCs were infected with different multiplicities of infection (MOI) of reovirus T3D. At different time points, the quantity of progeny viruses has been measured using virus titration assay and quantitative real-time polymerase chain reaction (qRT-PCR) to investigate the ability of these cells to support the reovirus replication. One-step growth cycle were examined by 50% cell culture infectious dose (CCID50) and qRT-PCR. RESULTS: The growth curve of reovirus in cells shows that MOI: 1 might be optimal for virus production compared to higher and lower MOIs. The maximum quantity of virus production using MOI: 1 was achieved at 48-hours postinfection. The infectious virus titer became stationary at 72-hours post-infection and then gradually decreased. The virus cytopathic effect was obvious in MSCs and this cells were susceptible to reovirus infection and support the virus replication. CONCLUSION: Our data highlights the timing schedule for reovirus replication, kinetics models and burst size. Further investigation is recommended to better understanding of the challenges and opportunities, for using MSCs loaded with reovirus in cancer-therapy.