Gene Therapy for Cancer a New Era in Cancer Treatment

Gene Therapy Cancer Treatment​

Cancer gene therapy refers to deriving a method of treatment whereby genes are altered in cancer cells or immune cells in the body that have a role of combating cancer cells. It is still considered to be rather new and some of them are still in experimental stage while others have received approval.

Gene Therapy for Cancer

Gene Addition Therapy

• Chimeric antigen receptor T cells targets or modify new or modified genes in the Cancer cells with the aim of either targeting or killing them.
• For instance, T-VEC (Talimogene Laherparepvec) is a melanoma therapy in which a herpes virus is utilized to target cancer cells.

Gene Editing (CRISPR/Cas9 and Other Technologies)

• Corrects wrong DNA to fix the genes which are leading to cancer.
• Example: CRISPR is also used scientific investigations in order to genetically alter immune cells of T cells in order to combat cancer.

Suicide Gene Therapy

• Introduces a gene that revives the responsiveness of tumor cells to a particular therapy to cause their destruction.
• Example: Herpes Simplex Virus Thymidine Kinase (HSV-TK) with ganciclovir.

Immunogene Therapy or also known as Genetically Engineered Immune Cells.

• Enhances specific immune cells in order to target and eliminate cancer cells.
• For example, CAR-T Cell Therapy which is Chimeric Antigen Receptor T cells that are designed for leukemia as well as lymphoma.

Oncolytic Virus Therapy

• Treats cancer through the method of bio-viral therapeutics in which genetically modified viruses are introduced into the body with an aim of attacking the cancer cells.
• Example: T-VEC for melanoma.

Gene Therapy for Lung Cancer​

Application of gene therapy has emerged as relevant tool for cancer treatment with lung cancer, specifically NSCLC being considered as a suitable candidate for this treatment. It involves altering of genes in carcinogenic cells or immune cells in a way that inhibits cell growth of tumor or improves immune activity against cancerous cells or makes the cancerous cells to be more susceptible to treatment.

Types of Gene Therapy for Lung Cancer

Tumor-Suppressor Gene Therapy

• Function: Replaces or repairs the mutated tumor suppressor genes that are absent or have been impaired in cancerous cells to prevent cancer development.

Suicide Gene Therapy

• To introduce a gene which would ensure that the cancer cells are programmed to die the moment they are subjected to a particular medicine.

Oncolytic Virus Therapy

• Aims to demonstrate the effective killing of lung cancerous cells using genetically modified viruses without affecting other healthy cells.

CAR-T Cell Therapy for Lung Cancer

• Function: Bioengineering of T cells, namely immunotherapy that enables the immune T cells to target lung cancer cells.

RNA-Based Gene Therapy

• Most products are based on small interfering RNA (siRNA), which disables cancer-promoting genes.

Gene Therapy for Breast Cancer​

Gene therapy is considered as a possible cure for breast cancer, especially in cases with aggressive or non-responsive to treatment cycles like TNBC and HER2-positive BC. It is to either fix defective genes, boost the ability of the immune system or to make cancer cells more vulnerable to medications.

CRISPR Cancer Therapy​

CRISPR or Clustered Regularly Interspaced Short Palindromic Repeats is the revolutionary technique for editing the genes of an organism. In cancer therapy, CRISPR enhances the genes of cancer cells or immune cells to influence cancer therapy.

How CRISPR Works in Cancer Therapy

• Gene knockout is done through a process known as CRISPR, used to mute the genes that are known to produce cancer.
• Gene Correction – Repairs mutations in tumor-suppressor genes.
• Immune Cell Engineering: This is achieved by making immune cells to become more subtle and sensitive to detecting cancer cells.
• Oncolytic Virus Enhancement – Increases viruses that are effective in eliminating cancer cells.

Immunotherapy Gene Editing​

Gene editing is revolutionizing cancer immunotherapy by modifying immune cells to more effectively see and kill cancer. Technologies such as CRISPR, TALEN, and Zinc Finger Nucleases (ZFNs) enable precise immune cell modifications to improve their anti-tumor function.

Types of Gene Editing in Immunotherapy

CRISPR-Edited CAR-T Cell Therapy

Purpose: Improves Chimeric Antigen Receptor (CAR)-T cells to better attack cancer cells.

TCR-T Cell Therapy (T Cell Receptor Therapy)

Purpose: Strengthens T cells by editing their T cell receptors (TCRs) to recognize cancer antigens more effectively.

CRISPR for Checkpoint Inhibitor Therapy

Purpose: Enhances immune checkpoint blockade therapy (e.g., PD-1/PD-L1 inhibitors).

Gene-Edited NK Cell Therapy (Natural Killer Cells)

Purpose: Strengthens NK cells, a category of immune cell that naturally destroys cancer.

Dendritic Cell Therapy with Gene Editing

Purpose: Spreads antigen-presenting dendritic cells (DCs) to enhance immune response.

Personalized Cancer Gene Therapy​

Personalized gene therapy for cancer is making treatments tailored according to a patient's genetic profile and tumor's molecular attributes. This will enhance the efficiency of treatment, decrease side effects, and achieve overcoming drug resistance.

How Personalized Gene Therapy Works

• Genomic Profiling & Biomarker Analysis
• Detection of mutations and genetic abnormalities present in a patient's tumor.
• Common targets: BRCA1/2, KRAS, EGFR, TP53, HER2, PIK3CA.
• Targeted Gene Therapy
• Utilizes gene-editing instruments such as CRISPR, TALEN, or viral vectors to edit genes in cancer cells or immune cells.
• Personalized Immunotherapy
• Augments immune response by employing genetically engineered T cells, NK cells, or dendritic cells.
• Drug Sensitivity Testing

Assists in determining the most potent drugs according to the genetic mutations in the tumor.

Gene Therapy Side Effects in Cancer​

Gene therapy is a promising method of cancer treatment, but it also has possible risks and side effects. These side effects may differ based on the type of gene therapy, delivery method, and patient response.

• Immune System Reactions
• Off-Target Effects
• Insertional Mutagenesis
• Toxicity from Gene Therapy Vectors
• Tumor Resistance & Recurrence