Restoring the p53 ‘Guardian’ Phenotype in p53-Deficient Tumor Cells with CRISPR/Cas9

• Published in: Trends in biotechnology (Regular ed.) 2018-07, Vol.36 (7), p.653-660
• Main Authors: Chira, Sergiu, Gulei, Diana, Hajitou, Amin, Berindan-Neagoe, Ioana
• Format: Article
• Language: English
• Subjects: AAVP tumor-target vector; Animals; Apoptosis; Cancer; Cancer therapies; Cell cycle; CRISPR; CRISPR-Associated Protein 9; CRISPR-Cas Systems; CRISPR/Cas9; Design; Disease Models, Animal; Efficiency; FDA approval; Gene Editing - methods; Gene expression; Gene therapy; Genetic Therapy - methods; Genetic Vectors; Genome editing; Genomes; Human populations; Humans; Localization; Metastasis; Mice; Mutation; Neoplasms - genetics; Neoplasms - therapy; p53 Protein; Phenotypes; Prognosis; Proteins; Tumor cells; tumor regression; Tumor suppressor genes; Tumor Suppressor Protein p53 - genetics; Tumors; Vectors (Biology)
• ISSN: 0167-7799; 1879-3096
• DOI: 10.1016/j.tibtech.2018.01.014

Limiting the CRISPR/Cas9-associated off-target effects is of major interest for increasing its clinical relevance. The original structure of the Cas9 nuclease has been modified to reduce unspecific cleavage, adding an extra level of complexity for obtaining the desired effects. Designing viral vectors that can efficiently differentiate diseased cells from normal cells has been a major challenge for cancer gene therapy. Complex engineering of the viral capsid is required to alter the natural tropism of the virus and redirect it to a desired cell type. Scaling-up viral vector production with good manufacturing practice standards is a costly procedure that requires cotransfection of producer cells with helper constructs, to obtain functional viral particles and subsequent high-tech purification methods for clinical grade vectors that are free of replication-competent virus. With an increasing prevalence in the human population, cancer has become one of the most investigated fields of medicine. Among the potential targets for cancer therapy is the tumor suppressor gene TP53, which is found in a mutated state in approximately 50% of human cancers and is often associated with poor prognosis. We propose a novel, highly tumor-specific delivery system for TP53, based on the CRISPR/Cas9 genome editing technology. This system will restore the normal p53 phenotype in tumor cells by replacing the mutant TP53 gene with a functional copy, leading to sustained expression of p53 protein and tumor regression.