Enhanced synergistic antitumor effect of a DNA vaccine with anticancer cytokine, MDA-7/IL-24, and immune checkpoint blockade

Miri, Seyed Mohammad and Pourhossein, Behzad and Hosseini, Seyed Younes and Keshavarz, Mohsen and Shahmahmoodi, Shohreh and Zolfaghari, Mohammad Reza and Mohebbi, Seyed Reza and Gorji, Ali and Ghaemi, Amir (2022) Enhanced synergistic antitumor effect of a DNA vaccine with anticancer cytokine, MDA-7/IL-24, and immune checkpoint blockade. Virology Journal. ISSN 1743-422X

[img] Text

Download (2MB)
Official URL: https://virologyj.biomedcentral.com/articles/10.11...


MDA-7/IL-24 cytokine has shown potent antitumor properties in various types of cancer without exerting any significant toxicity on healthy cells. It has also been proved to encompass pro-immune Th1 cytokine-like behavior. Several E7 DNA vaccines have developed against human papillomavirus (HPV)-related cervical cancer. However, the restricted immunogenicity has limited their clinical applications individually. To address this deficiency, we investigated whether combining the E7 DNA vaccine with MDA-7/IL-24 as an adjuvant would elicit efficient antitumor responses in tumor-bearing mouse models. Next, we evaluated how suppression of immunosuppressive IL-10 cytokine would enhance the outcome of our candidate adjuvant vaccine. Methods For this purpose, tumor-bearing mice received either E7 DNA vaccine, MDA-7/IL-24 cytokine or combination of E7 vaccine with MDA-7/IL-24 adjuvant one week after tumor challenge and boosted two times with one-week interval. IL-10 blockade was performed by injection of anti-IL-10 mAb before each immunization. One week after the last immunization, mice were sacrificed and the treatment efficacy was evaluated through immunological and immunohistochemical analysis. Moreover, the condition of tumors was monitored every two days for six weeks intervals from week 2 on, and the tumor volume was measured and compared within different groups. Results A highly significant synergistic relationship was observed between the E7 DNA vaccine and the MDA-7/IL-24 cytokine against HPV-16+ cervical cancer models. An increase in proliferation of lymphocytes, cytotoxicity of CD8+ T cells, the level of Th1 cytokines (IFN-γ, TNF-α) and IL-4, the level of apoptotic markers (TRAIL and caspase-9), and a decrease in the level of immunosuppressive IL-10 cytokine, together with the control of tumor growth and the induction of tumor regression, all prove the efficacy of adjuvant E7&IL-24 vaccine when compared to their individual administration. Surprisingly, vaccination with the DNA E7&IL-24 significantly reduced the population of Regulatory T cells (Treg) in the spleen of immunized mice compared to sole administration and control groups. Moreover, IL-10 blockade enhanced the effect of the co-administration by eliciting higher levels of IFN-γ and caspase-9, reducing Il-10 secretion and provoking the regression of tumor size. Conclusion The synergy between the E7 DNA vaccine and MDA-7/IL-24 suggests that DNA vaccines’ low immunogenicity can be effectively addressed by coupling them with an immunoregulatory agent. Moreover, IL-10 blockade can be considered a complementary treatment to improve the outcome of conventional or novel cancer therapies.

Item Type: Article
Subjects: WC Communicable Diseases
Divisions: Faculty of Medicin > Department of Infectious Diseases
Depositing User: خدیجه شبانکاره
Date Deposited: 10 Oct 2022 10:47
Last Modified: 10 Oct 2022 10:47
URI: http://eprints.bpums.ac.ir/id/eprint/9569

Actions (login required)

View Item View Item