Table 1 CRISPR-based strategies for cancer therapy

Inactivating genes that drive tumor growth

Targeting and disrupting oncogenes and tumor suppressor genes to stop cancer cell growth and induce apoptosis

Precision targeting: CRISPR can be designed to target specific genes or mutations that drive tumor growth, increasing specificity and reducing off-target effects. High efficacy: Studies have shown that inactivating certain genes using CRISPR can result in tumor regression and increased survival in animal models

Potential for off-target effects: While CRISPR offers high specificity, there is still the potential for unintended changes in the genome that could cause harm to the patient. Difficulty targeting specific genes or delivering therapy to tumor site: Some tumors may be difficult to target using current delivery methods

Study showed efficacy of using CRISPR to inactivate KRAS oncogene in mouse model of lung cancer. This is a major milestone since KRAS mutations are notoriously difficult to target with other therapies

[16]

Enhancing immune response to cancer cells

Editing immune cells to recognize and destroy cancer cells, such as by editing T cells to express chimeric antigen receptors (CARs)

Enhances body's natural immune response: By editing immune cells to recognize and attack cancer cells, CRISPR-based immunotherapy can activate the body's natural immune response to fight the cancer. Avoids toxic effects of chemotherapy: Unlike chemotherapy, which can have significant side effects, immunotherapy using CRISPR-edited T cells has the potential to be a more targeted and less toxic treatment approach

Potential for toxicity or immune rejection: There is a risk that CRISPR-edited immune cells could attack healthy cells or be rejected by the patient's immune system. Limited availability of specific T cells for editing: It can be challenging to obtain a sufficient number of T cells for editing, which could limit the widespread use of this approach

Study reported complete remission in two out of three patients treated with CRISPR-edited T cells in a trial for refractory lymphomas. This is a promising result, although more research is needed to determine the safety and efficacy of this approach in larger patient populations

[17]

Repairing genetic mutations that cause cancer

Correcting genetic mutations in tumor suppressor genes, DNA repair genes, or other driver genes

Precision targeting: CRISPR can be used to correct specific genetic mutations that cause cancer, potentially leading to long-term benefits. Potential for long-term benefits: Repairing genetic mutations that cause cancer could potentially result in long-term benefits for patients

Potential for off-target effects: As with other CRISPR-based approaches, there is a risk of unintended changes to the genome that could cause harm to the patient. Difficulty delivering therapy to tumor site: It can be challenging to deliver CRISPR-based therapy directly to the tumor site

Promising results in preclinical studies, such as using CRISPR to correct BRCA1 mutations in ovarian cancer cells

[18]

Delivering cancer-killing molecules directly to tumor cells

Using CRISPR to edit the genome of a virus or bacteria to specifically target cancer cells, delivering therapeutic molecules such as toxins or immune modulators directly to tumor cells

Precision targeting: By editing the genome of a virus or bacteria to specifically target cancer cells, CRISPR-based therapy can offer highly targeted and specific delivery of therapeutic molecules to tumor cells. High efficacy: Studies have shown that CRISPR-mediated delivery of cancer-killing molecules can result in tumor regression and increased survival in animal models

Potential for off-target effects: As with other CRISPR-based approaches, there is a risk of unintended changes to the genome that could cause harm to the patient. Limited availability of specific viruses or bacteria for editing: It can be challenging to obtain a sufficient number of specific viruses or bacteria for editing, which could limit the widespread use of this approach

Promising results in preclinical studies, such as using CRISPR to deliver CRISPRa to activate tumor-suppressive microRNAs in liver cancer cells. Other examples include using CRISPR to deliver toxic payloads to tumor cells, such as in a study where CRISPR was used to engineer bacteria to produce a toxin that specifically targets cancer cells in a mouse model of pancreatic cancer

[17, 18]