Cancer Genetics and Epigenetics, 2025, Vol.13, No.1, 41-49 http://medscipublisher.com/index.php/cge 43 research of HER2-positive breast cancer, this technology can specifically intervene in oncogenes such as HER2-these genes often show high amplification expression in this subtype. Its working mechanism is to precisely locate the Cas9 enzyme to the target gene region through guide RNA, triggering DNA double-strand breaks. The autonomous repair mechanism of cells then intervenes, usually leading to gene inactivation or mutations at specific sites (Wang and Sun, 2017; Wang et al., 2017; Liu et al., 2019). In breast cancer research, scientists constructed a HER2 deletion model through CRISPR technology and found that the deletion of this gene would hinder the division and survival of cancer cells. With the help of this model, the team also recorded the comprehensive changes in the gene activities of cancer cells, providing key clues for understanding the evolution patterns of tumors and formulating new treatment methods (Wang et al., 2017; Valashedi et al., 2022). 3.2 Discussion on the main advantages over traditional methods Compared with the earlier used gene editing platforms such as zinc finger nucleases (ZFNs) and TALENs, CRISPR/Cas9 has shown more prominent advantages in breast cancer research. This system is easy to operate and highly efficient-just introduce the guide RNA together with the Cas9 protein, and the target sequence can be accurately identified and edited, significantly reducing the experimental steps and reagent costs (Liu et al., 2019; Balon et al., 2022). More crucially, CRISPR/Cas9 supports multi-gene synchronous editing, providing reliable technical support for high-throughput screening of breast cancer targets. CRISPR technology has obvious targeting advantages and can effectively reduce the risk of off-target effects. In cancer research, this kind of accuracy is particularly important. Changes in non-target regions may lead to deviations in experimental data. This technology can also construct organoid models derived from specific mutations or patients, becoming an important tool for studying the mechanism of breast cancer and testing the efficacy of new drugs (Tiwari et al., 2023; Liu et al., 2024). 3.3 Progress in practical application in preclinical research CRISPR technology has been widely applied in preclinical models of breast cancer, especially in elucidating the regulatory mechanisms of key genes on tumor evolution and drug resistance. Typical applications include constructing HER2 gene knockout/overexpression models and systematically evaluating the impact of this gene mutation on drug response and malignant phenotypes. These models provide key data support for optimizing targeted therapy regiments and cracking drug resistance mechanisms (Figure 1) (Li et al., 2021; Liu et al., 2024). Figure 1 Potential therapeutic clustered regularly interspaced short palindromic repeats (CRISPR)-mediated targeting strategies for cancer gene therapy (Adopted from Liu et al., 2024) Image caption: The priority option for cancer gene therapy is the disruption of oncogenes rather than repairing inactivated tumor suppressor genes; The bar charts show the top-ten mutated genes in different cancers based on the COSMIC database (v87); Mutation frequencies have been calculated using a weighted average mutation frequency based on sample size across all studies (Adopted from Liu et al., 2024)
RkJQdWJsaXNoZXIy MjQ4ODYzNA==