CRISPR/Cas9: A powerful genome editing technique for the treatment of cancer cells with present challenges and future directions

Abstract

Cancer is one of the most leading causes of death and a major public health problem, universally. According to accumulated data, every year, approximately 8.5 million people died because of the lethality of cancer. Recently, a new RNA domain-containing endonuclease-based genome engineering technology, namely the clustered regularly interspaced short palindromic repeat (CRISPR)-associated protein-9 (Cas9) have been proved as a powerful technique in the treatment of cancer due to its multifunctional properties including high specificity, accuracy, time reducing and cost-effective strategies with minimum off-target effects. The present review investigates the overview of recent studies on the newly developed genome-editing strategy, CRISPR/Cas9, as an excellent pre-clinical therapeutic option in the reduction and identification of new tumor target genes in the solid tumors. Based on accumulated data, we revealed that CRISPR/Cas9 significantly inhibited the robust tumor cell growth (breast, lung, liver, colorectal, and prostate) by targeting the oncogenes, tumor-suppressive genes, genes associated to therapies by inhibitors, and genes associated to chemotherapies drug resistance, and suggested that CRISPR/Cas9 could be a potential therapeutic target in inhibiting the tumor cell growth by suppressing the cell-proliferation, metastasis, invasion and inducing the apoptosis during the treatment of malignancies in the near future. The present review also discussed the current challenges, and barriers and proposed future recommendations for a better understanding.

Targeting Cancer with CRISPR/Cas9-Based Therapy

“…Another obstacle to AAV-based CRISPR/Cas9 delivery is its low capacity. AAVs can pack up to approximately 5 kbp of DNA in a payload (including viral flanking sequences), while the SpCas9 gene itself is about 4.1 kbp long [ 9 , 18 , 45 ] and introduced genes usually require the addition of a suitable promoter to undergo transcription. The main strategy to circumvent this is to load the Cas9 gene and sgRNA into separate AAV vectors introduced simultaneously.…”

“…In principle, gene editing techniques employ various nucleases to introduce single or Double-strand breaks (DSBs) to the DNA strand at a specific site to install a permanent change in the genome. The first attempts at genetic therapies in oncology were based on Zinc-finger nucleases (ZFNs) or Transcription activator-like effector nucleases (TALENs) [ 9 ]. Both systems employ nuclease FokI and recognise targeted sequence with carefully engineered protein sets which physically interact with selected DNA fragment.…”

“…Both systems employ nuclease FokI and recognise targeted sequence with carefully engineered protein sets which physically interact with selected DNA fragment. Unfortunately, therapies based on ZFNs or TALENs are less feasible for diverse applications as the process of re-engineering guiding proteins is costly and time-consuming [ 9 , 10 ].…”

An Overview of the Role of Long Non-Coding RNAs in Human Choriocarcinoma

“…Therefore, it is possible to achieve transcriptional silencing of lncRNAs via CRISPR-based approaches, however, several challenges limit their immediate use for therapeutic targeting [ 120 , 121 , 122 , 123 ]. Major limitations include delivery methods (viral and non-viral vectors), with viral vectors limited in the size of the cargo they are able to deliver to the cells of interest [ 124 , 125 , 126 , 127 ]. Regardless of the current limitations, the future undoubtedly looks bright for CRISPR-directed lncRNA therapies.…”

Clustered Regularly Interspaced Short Palindromic Repeat Analysis of Clonal Complex 17 Serotype III Group B Streptococcus Strains Causing Neonatal Invasive Diseases

“…Clustered regularly interspaced short palindromic repeats (CRISPR) are composed of short (25–40 base pairs) direct repeats interspaced by nonrepetitive similar-sized sequences called spacers [ 15 , 16 ]. CRISPR-associated protein-9 (Cas9)-mediated genome modification is a novel RNA-domain-containing endonuclease-based genome editing technology for a variety of biological and therapeutic applications [ 17 , 18 , 19 ].…”