GENOME EDITING CRISPR TECHNOLOGY

INTRODUCTION

Cancer Disease Is the Second MOST Prevalent CAUSE OF DEATH AS A RESULT OF THE RISK FACTOR THAT CAUSES MUTUTATION. The Philadelphia translocation, which also fuses breakpoint cluster region (BCR) sequence data from chromosome 22 upstream of an Abelson murine leukemia viral oncogene homolog (ABL) on chromosome 9, defines chronic myeloid leukemia (CML), necessitates targeted as well as efficient treatment. (Liu et al., 2018)

THE CRISPR/CAS9 TECHNOLOGY

CRISPR/Cas9 is a powerful tool for genetic engineering. gene editing-based therapeutics because it can make DNA cuts at sites in targeted genes. If a separate cut is made, a process called non-homologous end joining may occur, resulting in the deletion or addition of DNA bases inside the original DNA sequence and gene inactivation Traditional CRISPR-Cas9 editing techniques necessitate the design as well as the instead of an appropriate guidance RNA (gRNA) to aim genome cleavage, as well as a repair framework for introducing almost the same requisite site-specific genome sequencing change. The creation and human cloning of a completely unique guide RNA (gRNA) and make repairs template for every application of a range of different of CRISPR-based genome proofreading methods is a common part of this process. (Sachla and colleagues, 2021) The acronym CRISPR stands for (CLUSTERED REGULARLY INTERSPACED SHORT PALINDROMIC REPEAT)

Figure 1CRISPR/Cas9 Technology

DISRUPT: When a single new cut is made, a procedure called non end joining could occur, resulting in the addition or removal of base pairs, disrupting the initial DNA sequence and inactivating the gene.

DELETE: A wider fragment of DNA could be removed by using two guide RNAs that target different sites. Non-homologous stop joining reconnects the divided ends while simply removing the intervening sequence after cleavage at each site.

CHANGE OR INSERT: - The cell can also totally correct a gene and even introduce a new gene using a DNA template as well as the CRISPR/Cas9 machinery, a practice called as homology directed repair.(Dr. Charpentier, 2022)

DIAGNOSTICS

A balanced genetic translocation known as t (9;22) (q34;q11.2), which involves the fusion of the breakpoint cluster region (BCR) gene on chromosome 22q11.2 and the Abelson gene (ABL1) on chromosome 9q34, distinguishes CML from other types of cancer. This rearrangement is known as the Philadelphia chromosome. A BCR: ABL1 fusion oncogene is created as a result of this translocation, and it then transduces into a BCR:: Oncoprotein ABL1.(Jabbour & Kantarjian, 2022a)

Frontline therapy: Imatinib, dasatinib, bosutinib, and nilotinib have all received approval from the US Food and Drug Administration to be used as the first-line treatments for newly diagnosed chronic myeloid leukemia (CML). Due to the availability of potent TKI salvage therapies for patients who experience cytogenetic relapse after receiving frontline TKI therapy, second-generation TKI clinical trials reported significantly deeper and faster responses but had no impact on survival prolongation.

Salvage therapy: Patients with CML who have not responded to frontline therapy are eligible for salvage therapy with second and third generation TKIs. All current TKIs, except for ponatinib, asciminib, and olverembatinib, are ineffective against patients who acquire the T315I "gatekeeper" mutation (Jabbour & Kantarjian, 2022b).

SCREENING

20% to 30% of first-time imatinib patients stop taking it because of intolerance and/or resistance, even though the vast majority of them reach a "safe haven," which is only a confirmed MMR. To identify patients who will benefit the most from switching to second-line therapy, such as another TKI or an allograft, cytogenetics and RQ-PCR are primarily used to monitor response. It might become a low-cost, minimally invasive way to screen for CML, opening the door to perhaps earlier detection and treatment (Panda et al., 2022).

Figure 3CRISPR screening

BEND The most important gene whose knockout confers resistance to TAK-243 in vitro and in vivo is BEND3, a transcriptional repressor and regulator of chromatin organization. In cancer cell lines of various origins, it was discovered that TAK-243 sensitivity was connected to BCRP expression. These results indicate that BCRP, a substrate for TAK-243, is controlled by BEND3 levels. Additionally, BCRP can predict TAK-243 sensitivity (Barghout et al., 2021).

PREVENTION

In CML LSCs and NK cells, respectively, bone marrow microenvironment (BMM) signals activate MIR300 to cause quiescence and reduce immune response. MIR300 and PP2A activity have the same relevance for the development and treatment of CML because biological and pharmacologic MIR300 modulation and/or PP2A-activating drug therapy restore NK cell activity, prevent BMM-induced growth arrest, and selectively trigger LSC (Silvestri et al., 2020).

STATISTIC

The overall perception of information provision was 42.8. (0–100). The availability of information on other services, such as psychological support and rehabilitation, as well as the impact of treatment on sexuality, could be improved. One in three people knew where to look on the internet for helpful health information. However, 36% of them demanded more details. Age 65, the number of years since diagnosis, and a low level of education were all linked to this need.The most popular pages were those about medications and side effects (Ector et al., 2022).

1328 patients with CP CML who were diagnosed between 2002 and 2017 were included in the study. A total of 329 patients received care for more than 10 years, with the median follow-up period being 6 years (interquartile range [IQR], 3–10 years). There were 613 patients, and 46% of them were female. Table 1 displays the baseline characteristics of the CML and control cohorts. According to Table 2, 1213 (91%), 379 (29%), 388 (29%), 52 (4%), and 25 (2%) patients, respectively, received imatinib, dasatinib, nilotinib, bosutinib, and ponatinib. Patients receiving ponatinib were younger (64% received it as a third or later TKI treatment), in later treatment lines, and younger (median age, 51 years) (Table 2). For the entire cohort, there were 8510 person-years of follow-up, with. The total number of person-years of follow-up for the entire cohort was 8510, with 5985, 1143, 1288, 61 and imatinib, dasatinib, nilotinib, bosutinib, and ponatinib, with 5985, 1143, 1288, 61, and 21 person-years, respectively (Dahlén et al., 2022).

Additional tests might be required.

The three treatment objectives for chronic myelogenous leukemia (CML) have changed significantly over the past ten years. Hematologic recovery (normal CBC and physical examination); cytogenetic remission (normal chromosome resumption with 0% Philadelphia chromosome-positive (Ph+) cells); and molecular remission (a negative polymerase chain reaction [PCR] result for the mutant BCR/ABL mRNA), which suggests a potential cure and patient survival(Druker et al., 2001).

To ensure proper and substantiate regional diagnostic procedures from 2016 to 2021, the European Treatment and Outcome Study for CML (EUTOS) investigated the use of supplementary, lyophilized cell-based BCR: ABL1 reference panels traceable to WHO standard reference. Secondary reference panels, based on the research results, can be utilized successfully to acquire, and verify CFs in a way commensurate to specimen exchange, in addition, to monitoring additional quality assurance factors (White et al., 2022).

Asciminib is now approved for the management of persistent chronic myeloid leukemia individuals who have failed two lines of therapeutic interventions or have the T315I mutation as the first allosteric inhibitor of BCR: ABL1 kinase action. Gene editing methods typically use a variety of nucleases to add fresh single or double-strand breaks (DSBs) to the DNA strand and at a particular site to alter the genome completely (Yeung et al., 2022).