CRISPR-to-Kill (C2K)–Employing the Bacterial Immune System to Kill Cancer Cells
1
Research Department, Cell and Gene Therapy, Department of Stem Cell Transplantation, University Medical Center Hamburg-Eppendorf (UKE), 20246 Hamburg, Germany
2
Department of Neurosurgery, University Medical Center Hamburg-Eppendorf (UKE), 20246 Hamburg, Germany
*
Author to whom correspondence should be addressed.
Cancers 2021, 13(24), 6306; https://doi.org/10.3390/cancers13246306
Submission received: 28 October 2021
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Revised: 1 December 2021
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Accepted: 10 December 2021
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Published: 15 December 2021
(This article belongs to the Section Cancer Therapy)
Simple Summary
Reasoning that multiple DNA breaks will trigger programmed cell death, we generated lentiviral CRISPR-to-kill (C2K) vectors targeting highly repetitive SINE sequences for cancer gene therapy. In proof-of-concept experiments, C2K-Alu-vectors selectively killed human, but not murine cell lines, and efficiently inhibited the growth of patient-derived glioblastoma cell lines resistant to high-dose irradiation. In combination with tumor-targeting approaches, the C2K system might represent a promising tool for cancer gene therapy.
Abstract
CRISPR/Cas9 was described as a bacterial immune system that uses targeted introduction of DNA double-strand breaks (DSBs) to destroy invaders. We hypothesized that we can analogously employ CRISPR/Cas9 nucleases to kill cancer cells by inducing maximal numbers of DSBs in their genome and thus triggering programmed cell death. To do so, we generated CRISPR-to-kill (C2K) lentiviral particles targeting highly repetitive Short Interspersed Nuclear Element-Alu sequences. Our Alu-specific sgRNA has more than 15,000 perfectly matched target sites within the human genome. C2K-Alu-vectors selectively killed human, but not murine cell lines. More importantly, they efficiently inhibited the growth of cancer cells including patient-derived glioblastoma cell lines resistant to high-dose irradiation. Our data provide proof-of-concept for the potential of C2K as a novel treatment strategy overcoming common resistance mechanisms. In combination with tumor-targeting approaches, the C2K system might therefore represent a promising tool for cancer gene therapy.
