Related Experiment Videos
[Gene therapy for cancer]
1Fourth Department of Internal Medicine, Sapporo Medical University School of Medicine, Japan.
Abstract:
The strategies of gene therapy for cancer can be classified as: 1. regulation of oncogenes and anti-oncogenes, 2. immunogenetherapy, 3. support of chemotherapy, 4. suicide gene therapy, and 5. gene marking. The first one is the strategy to inhibit the expression of oncogenes by their antisenses or rhybozymes, or to introduce anti-oncogenes into those tumor cells with the inactivate effector cells (lymphocytes) by transducing cytokine genes, etc., followed by retransfering the gene-modified effector cells to patients (adoptive immunotherapy). The other one is to augment antigenicity of tumor cells. The immunogenetherapy method has been widely used for 70% of gene therapy of human cancer, because cells can be transduced ex vivo. The anti-tumor effects of human gene therapy using a GM-CSF gene by Muligan et al. or an IL-2 gene by Tahara and Lotze are expected. The third is the strategy to protect bone marrows from large dose of anti-cancer drug by transducing a multidrug resistance gene into those bone marrow cells or periphen blood stem cells, overcoming dose limiting of the drug. The fourth strategy is to transduce the herpes simplex virus thymidine kinase (KSV-TK) gene for activating the cytocydal prodrug (ganciclovir: GCV) into tumor cells in order to kill the tumor cells themselves following administration of GCV. At present, vectors most widely used for gene transduction are retroviruses and adenoviruses. However, the transduction using these vectors are primarily conducted ex vivo. The direct in vivo gene delivery method to target tumor cells are required.
Insights
Gene therapy offers five cancer treatment strategies, including regulating oncogenes, immunotherapy, chemotherapy support, suicide gene therapy, and gene marking. Immunotherapy is widely used, but in vivo delivery methods are needed.
Area of Science:
- Oncology
- Molecular Biology
- Immunology
Context:
- Cancer gene therapy encompasses diverse strategies to combat malignancies.
- Current methods often rely on ex vivo gene transduction, limiting broader application.
Purpose:
- To outline and categorize the primary strategies employed in cancer gene therapy.
- To highlight the mechanisms and potential of various gene therapy approaches.
Summary:
- Gene therapy for cancer involves five main strategies: oncogene/anti-oncogene regulation, immunotherapy, chemotherapy support, suicide gene therapy, and gene marking.
- Immunotherapy, particularly ex vivo transduction of immune cells, is a prevalent approach.
- Suicide gene therapy utilizes genes like HSV-TK to selectively kill tumor cells upon prodrug administration.
- Chemotherapy support involves enhancing drug resistance in stem cells to enable higher dosages.
Impact:
- Gene therapy presents promising avenues for cancer treatment, with immunotherapy showing significant clinical application.
- Further development of in vivo gene delivery systems is crucial for expanding the reach and efficacy of cancer gene therapy.