CRISPR is a naturally-occurring biological defense found in a wide range of bacteria. Decades ago bacteriologists observed strange patterns in some bacterial genomes, with particular DNA sequences repeated over and over, and with unique DNA sequences between the repeated material. They called this odd arrangement “clustered regularly interspaced short palindromic repeats,” or CRISPR. When it was subsequently discovered that the unique DNA sequences located between the repeats matched the DNA of viruses known to prey on bacteria, it became apparent that CRISPR is part of a bacterial immune system. This system accordingly “holds on” to pieces of viral genome in order to later identify and destroy those viruses next time they attack. To actually destroy the viral invaders, a set of enzymes called Cas (CRISPR-associated proteins), snip the viral DNA of invading viruses in order to render them harmless.
The CRISPR/Cas genome editing methodology found in nature has now been ported to the laboratory where it has been suggested as a weapon against human viruses [1]. Similarly, it has been suggested as a means to induce or turn off gene expression to treat (for instance) autoimmune disease by manipulating how much of a partricular anti-inflammatory protein is made [2]. Now it looks like CRISPR/Cas may be useful in fighting cancer.
All cancers have genetic mutations that result in damaged cellular operation [3]. These pathological changes to cellular programming may variously result in unwanted effects such as unrestricted cellular proliferation via unregulated cell growth or the induction of enzymes that render chemotherapeutic agents ineffective. This article [4] explains how CRISPR/Cas9 – based tools might allow researchers to precisely edit the genetic mechanism underlying cellular control for clinical purposes. However, the authors emphasize that the road ahead may not be straightforward: “Perhaps the greatest challenge ahead is the efficient delivery of CRISPR/Cas9 to the targeted cancer cells. A number of approaches are possible including viral transduction using adenovirus, adeno-associated virus (AAV) or lentiviruses and nonviral physical methods.”
REFERENCES
1: White MK, Hu W, Khalili K. The CRISPR/Cas9 genome editing methodology as a weapon against human viruses. Discov Med. 2015 Apr;19(105):255-62. Review. PubMed PMID: 25977188; PubMed Central PMCID: PMC4445958.
2: Jing W, Zhang X, Sun W, Hou X, Yao Z, Zhu Y. CRISPR/CAS9-Mediated Genome Editing of miRNA-155 Inhibits Proinflammatory Cytokine Production by RAW264.7 Cells. Biomed Res Int. 2015;2015:326042. doi: 10.1155/2015/326042. Epub 2015 Nov 30. PubMed PMID: 26697483; PubMed Central PMCID: PMC4677169.
3: Pelengaris S, Khan M (Eds): The Molecular Biology of Cancer, Second Ed. Wiley- Blackwell, 2013. ISBN-10: 1118022874
4: White MK, Khalili K. CRISPR/Cas9 and cancer targets: future possibilities and present challenges. Oncotarget. 2016 Mar 15;7(11):12305-17. doi:10.18632/oncotarget.7104. Review. PubMed PMID: 26840090; PubMed Central PMCID: PMC4914286.
The CRISPR/Cas genome editing methodology found in nature has now been ported to the laboratory where it has been suggested as a weapon against human viruses [1]. Similarly, it has been suggested as a means to induce or turn off gene expression to treat (for instance) autoimmune disease by manipulating how much of a partricular anti-inflammatory protein is made [2]. Now it looks like CRISPR/Cas may be useful in fighting cancer.
All cancers have genetic mutations that result in damaged cellular operation [3]. These pathological changes to cellular programming may variously result in unwanted effects such as unrestricted cellular proliferation via unregulated cell growth or the induction of enzymes that render chemotherapeutic agents ineffective. This article [4] explains how CRISPR/Cas9 – based tools might allow researchers to precisely edit the genetic mechanism underlying cellular control for clinical purposes. However, the authors emphasize that the road ahead may not be straightforward: “Perhaps the greatest challenge ahead is the efficient delivery of CRISPR/Cas9 to the targeted cancer cells. A number of approaches are possible including viral transduction using adenovirus, adeno-associated virus (AAV) or lentiviruses and nonviral physical methods.”
REFERENCES
1: White MK, Hu W, Khalili K. The CRISPR/Cas9 genome editing methodology as a weapon against human viruses. Discov Med. 2015 Apr;19(105):255-62. Review. PubMed PMID: 25977188; PubMed Central PMCID: PMC4445958.
2: Jing W, Zhang X, Sun W, Hou X, Yao Z, Zhu Y. CRISPR/CAS9-Mediated Genome Editing of miRNA-155 Inhibits Proinflammatory Cytokine Production by RAW264.7 Cells. Biomed Res Int. 2015;2015:326042. doi: 10.1155/2015/326042. Epub 2015 Nov 30. PubMed PMID: 26697483; PubMed Central PMCID: PMC4677169.
3: Pelengaris S, Khan M (Eds): The Molecular Biology of Cancer, Second Ed. Wiley- Blackwell, 2013. ISBN-10: 1118022874
4: White MK, Khalili K. CRISPR/Cas9 and cancer targets: future possibilities and present challenges. Oncotarget. 2016 Mar 15;7(11):12305-17. doi:10.18632/oncotarget.7104. Review. PubMed PMID: 26840090; PubMed Central PMCID: PMC4914286.