Cervical cancer is the second-most-common cause of malignancies in women worldwide, and the oncogenic activity of the human papilloma virus types (HPV) E7 protein has a crucial role in anogenital tumors. In this study, we have designed a therapeutic vaccine based on chitosan nanodelivery systems to deliver HPV-16 E7 DNA vaccine, considered as a tumor specific antigen for immunotherapy of HPV-associated cervical cancer. We have developed a Nano-chitosan (NCS) as a carrier system for intramuscular administration using a recombinant DNA vaccine expressing HPV-16 E7 (NCS-DNA E7 vaccine). NCS were characterized in vitro for their gene transfection ability.

Oncolytic viruses (OVs) have emerged as a novel cancer treatment modality, which selectively target and kill cancer cells while sparing normal ones. Among them, engineered Herpes Simplex Virus type 1 has been proposed to be employed as a potential treatment of cancer and was moved to phase III clinical trials. In this study, to improve oncoselectivity and oncotoxicity properties, the UL39 gene of the ICP34.5 deleted HSV-1 was manipulated with the insertion of the EGFP-p53 expression cassette utilizing CRISPR/ Cas9-mediated editing genome. The ΔUL39/Δγ34.5/HSV1-p53 mutant was isolated using the chorioallantoic membrane (CAM) of fertilized chicken eggs as a complementing membrane to support the growth of the viruses with gene deficiencies. Phenotypic characterization of ΔUL39/Δγ34.5/HSV1-p53-infected cells was compared with the parent Δγ34.5/HSV-1 in vitro. Our results indicate that the CAM model can be a promising strategy for isolating recombinant virus such as HSV-1-P53 that is unable to replicate in cell lines due to the death induced by exogenous p53 during virus replication.

Exploiting herpes simplex virus type 1 (HSV-1) has recently emerged as a new strategy to improve the treatment of patients with various cancers resistant to chemotherapy and associated with a poor prognosis due to its ability to infect tumor cells without causing harm to healthy cells. It has been suggested as a new platform for cancer therapy. Gene-modification techniques such as conventional homologous recombination or CRISPR/Cas9 system are utilized to introduce site-specific mutations in targeted viral genes. Although, the CRISPR-Cas9 system could significantly increase the efficiency of homologous recombination; nevertheless the process of purifying recombinant variants can be tedious. Here we present a rapid, innovative method using non-permissive hamster ovary (CHO) cells which is a remarkable improvement on the previously mentioned tedious process. Using this strategy, only 1–2 rounds of plaque purification would suffice. Our proposed protocol demonstrated high potential as a worthy alternative way for the current approaches of the isolation and purification of the fluorescent reporter genes-expressing recombinant HSV-1 by plaque assay using CHO cells.