What is CRISPR/Cas9 and how can it help treat Cancer?
The field of genetic engineering has rapidly advanced with the emergence of clustered regularly interspaced short palindromic repeats (CRISPR)‐associated system (Cas) (CRISPR/Cas) genome editing strategy. CRISPR/Cas9 is the simplest and best-studied subtype of CRISPR that won a Nobel Prize in 2020; with recent advances, it gained much attention in the scientific field [1]. So what is this all about?
CRISPR/Cas9 complex consists of guide RNA (gRNA) and a Cas9 enzyme. The gRNA is designed to recognise a specific section of DNA, and its job is to direct the Cas9 enzyme to that. When the gRNA binds to the targeted sequence, the enzyme is directed to that location in the genome, where it acts as a pair of molecular scissors, cutting both strands of the DNA, which results in a double-strand break. At this point, the cell’s natural defences take over, trying to fix the damage by joining the strands back or inserting the new genetic material.
Initially, this system was used by bacteria as a defence mechanism against bacteriophages and viruses that target bacteria. When the virus first infects the bacteria, it incorporates short parts of the viral DNA in special sections of its DNA called CRISPR array so that if the same virus infects bacteria again, these DNA sections guide the Cas9 enzyme to the viral DNA to cut it and prevent the virus from replicating. [2]
CRISPR/Cas9 system can be easily programmed to target any DNA sequence by changing the gRNA. [1]
Because Cancer cells appear after multiple mutations in their DNA, CRISPR/Cas9 can become a game changer in cancer treatment. If we can change the DNA of Cancer cells, we will be able to prevent them from dividing and getting bigger or make them more ‘visible to the immune system’.
Nowadays, the potential of CRISPR/Cas9 is investigated in different Cancers. In lung Cancer, it is investigated to identify and modify a mutated epidermal growth factor receptor (EGFR) gene that is responsible for uncontrollable cell growth. This can prevent Cancer cells from growing. In liver Cancer, CRISPR/Cas9 is used to target a protein responsible for cell migration and invasion. In pancreatic cancer, CRISPR/Cas9 is investigated to knock out some genes of the Cancer cells to weaken them [1].
Since the discovery of CRISPR/Cas9, the field of genetic engineering has advanced significantly, attracting considerable attention. Now, this novel system shows promise in cancer treatment. Maybe genetic engineering of cancer cells will become the base therapy for cancer in the future.
References:
Allemailem, K.S., Alsahli, M.A., Almatroudi, A., Alrumaihi, F., Alkhaleefah, F.K., Rahmani, A.H. and Khan, A.A. (2022). Current updates of CRISPR/Cas9‐mediated genome editing and targeting within tumor cells: an innovative strategy of cancer management. Cancer Communications, 42(12), pp.1257–1287. doi:https://doi.org/10.1002/cac2.12366.
Loureiro, A. and da Silva, G. (2019). CRISPR-Cas: Converting A Bacterial Defence Mechanism into A State-of-the-Art Genetic Manipulation Tool. Antibiotics, [online] 8(1), p.18. doi:https://doi.org/10.3390/antibiotics8010018.
