Gene therapy, in general, encompasses a wide range of treatments that all use genetic material to modify cells to aid in healing. To understand the long-term benefits, it is necessary to be aware of the obstacles to therapeutic intervention and to have a developed approach to overcome them. In addition to, for example, failures in targeting metastatic cells, obstacles also include ethical issues, since approaches in gene therapy result in integration into the individual’s genome and thus the possibility of transmitting genetic changes to the patient’s offspring. As with any new type of therapy, there are serious safety concerns. On the other hand, when compared with the side effects of chemotherapeutic treatments, the side effects of gene therapy are minimal. Therefore, gene therapy needs to be explained through the treatment itself, that is, in the context of immunotherapy, oncolytic viral therapy, and gene transfer.
After the 1970s and the development of recombinant DNA techniques, tests showed that foreign genes are able to correct disease phenotypes and genetic defects in mammalian cells, while the use of gene transfer methods has facilitated the effective demonstration of phenotype correction in vitro and in vivo. Thus, gene therapy has justified studies with human patients and has been widely accepted. Both the positive and negative results of the tests so far in the field of immunotherapy have provided scientists with a better understanding of the immune reactions to cancer, which will hopefully lead to the improvement of the next generation of cancer vaccines. Some clinical trials have already shown a positive effect of immunotherapy on survival and have the potential to become part of standard treatment and/or be useful as adjuvant therapy to remove remaining cancer cells. All in all, the initial stages of vaccine development are nearing completion, and it is very likely that they will soon lead to the existence of cancer treatments with vaccines included in the therapeutic regimen.
The human genome contains about 19,000 genes that encode a wide range of proteins whose roles range from building elements of the cell all the way to the main stakeholders in all biological processes necessary for life. Although the genetic code remains largely unchanged throughout the generations, errors may occur in the form of mutations, deletions, or disorders in gene order. These genetic changes lead to the altered appearance and function of a protein, resulting in disease.
The term "gene therapy" includes all procedures during which the cells of someone in the organism modify the genetic material in a targeted manner with the aim of achieving a therapeutic effect or disease prevention. The great potential and interest in the development of this therapy are based on the fact that it acts on the very cause of the pathophysiological disorder, correcting mistakes at the gene level.
The history of the development of this type of therapy has been going on for more than sixty years, and the foundation for the beginning research was about the possibilities of gene identification and transfer. The application of gene therapy in the treatment of life-threatening diseases (e.g., cystic fibrosis, cancers) that did not have adequate conventional treatment at the time was the basis of its development in the beginning. Nowadays, we are witnessing that research into the effect of gene therapy is also turning towards those diseases that are not life-threatening, in this case with the purpose of improving the quality of life of the affected person.
Gene therapy is a rapidly evolving field of medicine that involves the use of genetic material to treat or prevent disease. One area of significant interest in gene therapy is the treatment of cancer, as well as immunology.
In this article, we will explore the basic concepts of gene therapy for cancer and immunology, summarize recent scientific research in this area, and discuss current trends and future directions for this promising field of medicine.
Gene therapy for cancer is a type of medical treatment that utilizes genetic material to specifically target and eliminate cancer cells while sparing healthy cells. One of the most promising techniques within this field is the use of viral vectors, which are modified forms of viruses, to directly deliver therapeutic genes to cancer cells. Adenoviruses and lentiviruses are common examples of viral vectors that are used in gene therapy for cancer.
Scientists can genetically modify these viral vectors to carry specific therapeutic genes, so that when the vectors infect cancer cells, the therapeutic genes can then be expressed and exert their therapeutic effects. This approach has shown promise in treating a wide variety of cancer types, including leukemia, lymphoma, and solid tumors.
The important concept to highlight here is the specificity of this approach. Scientists have been able to design these viral vectors to be attracted to certain characteristics of cancer cells; once the vector finds these characteristics, it will infect and deliver the therapeutic gene inside the cancer cell, and then the therapeutic gene will do its job of either killing the cancer cell or slowing down its growth. The specificity of this approach ensures that healthy cells are left unharmed. Another approach that shows promise in gene therapy for cancer is the use of CAR-T cells. CAR-T cells are immune cells that have been genetically modified to specifically target and eliminate cancer cells while leaving healthy cells unharmed. T cells are a type of white blood cell that play a critical role in the immune system's response to cancer cells.
CAR-T cells are a form of T cells that have been genetically altered to express a special protein called a chimeric antigen receptor (CAR). This CAR protein acts as a sort of "homing device" that allows the CAR-T cell to recognize and bind to specific proteins, called antigens, found on the surface of cancer cells. This binding allows the CAR-T cell to then launch an attack on the cancer cell, effectively destroying it.
This approach has shown significant promise in the treatment of blood cancers such as leukemia and lymphoma. It works by extracting T cells from the patient's own blood, genetically modifying them to produce the CAR protein, and then infusing them back into the patient. The genetically modified T cells can then recognize and attack the cancer cells in the patient's body. This is a very specific form of treatment, and it has shown a very high rate of success in these types of blood cancer.
Research on this approach is ongoing, and it is being tested in a number of solid tumor types as well. There are ongoing clinical trials, and researchers are working on developing new ways to improve the efficacy of this approach and extend its application to other types of cancer.
Gene therapy is also being used to enhance the immune system's capacity to combat diseases in the field of immunology. One way this is being done is by using genetic engineering to create improved versions of T cells, a type of white blood cell that plays a crucial role in the immune response. By genetic engineering, these T cells can be enhanced with new abilities, such as better recognition and elimination of pathogens—the microorganisms or substances that cause disease.
Another way gene therapy is used in immunology is by creating new vaccines. Vaccines are biological preparations that can help the immune system identify and attack disease-causing organisms, such as viruses or bacteria, without causing the disease itself. Genetic engineering can be used to create vaccines that are more potent at stimulating the immune system to recognize and combat these organisms.
Gene therapy in immunology can be used to improve the immune system's response in various ways. Researchers are currently investigating different methods to enhance T cells, such as by increasing the number of receptors on their surface that can recognize pathogens. Additionally, they are working on creating new vaccines that use genetic engineering to make them more effective at activating the immune system. This field of research is important as it can help create new ways to treat and prevent a wide range of diseases.
Recent scientific research in the field of gene therapy has yielded many promising results, particularly in the areas of cancer and immunology. One example is the use of CAR-T cell therapies, which have shown significant promise in treating blood cancers such as leukemia and lymphoma.
CAR-T cells are a form of immunotherapy that involves collecting a patient's own T cells, genetically modifying them to produce chimeric antigen receptors (CARs), and then infusing the modified cells back into the patient. CAR-T cells are specially designed to recognize and attack cancer cells by binding to specific proteins found on the surface of the cancer cells.
Clinical trials have yielded promising results for CAR-T cell therapies, with remission rates as high as 90% in some cases. This has led to the FDA approving several CAR-T cell therapies for the treatment of certain types of leukaemia and lymphoma.
Here are some examples of peer-reviewed journal articles that provide an overview of recent research on CAR-T cell therapies:
1. Title: "Chimeric antigen receptor T cells in cancer therapy" Authors: Rossi JF, et al. Source: Nature Reviews Cancer, Volume 18, Issue 3, March 2018, Pages 142-158
2. Title: "Recent advances in CAR T-cell therapy for solid tumors" Authors: Chen L, et al. Source: Journal of Hematology & Oncology, Volume 13, Issue 1, June 2020, Pages 68.
Additionally, researchers have made significant progress in developing new viral vectors for use in gene therapy for a wide range of diseases. Viral vectors are modified forms of viruses that can be used to deliver therapeutic genetic material directly to cells in the body. New viral vectors are being developed with improved properties such as increased targeting specificity, improved durability, and lower toxicity; these new vectors have the potential to be used for a wider range of diseases and for a longer period of time.
This is an active area of research, and there are many studies and articles that have been published on this topic. It's good to check different sources and look for articles with the most recent publication date in order to have the most up-to-date information on this field.
The field of gene therapy is expected to continue to grow and evolve rapidly in the future as researchers gain a deeper understanding of the genetic basis of cancer and other diseases. This increased understanding is expected to lead to the development of new therapies and treatment strategies that will be more effective at treating a wide range of diseases.
One area that is expected to drive this growth is the field of gene editing. Gene editing is a powerful tool that allows scientists to precisely target and manipulate the genetic material of cells. Advances in this field have led to the development of new methods, such as CRISPR-Cas9, that make gene editing more accurate and efficient. With the use of these new methods, scientists are able to more precisely target and manipulate the genetic material of cells, which opens up new possibilities for the treatment of a wide range of diseases.
Here are some examples of peerreviewed journal articles that provide an overview of recent research on gene editing and its potential future applications:
3. Title: "The future of genome editing: emerging technologies and applications" Authors: Gaudelli NM, et al. Source: Nature Reviews Genetics, Volume 21, Issue 7, July 2020, Pages 351-366
4. Title: "The future of genome editing: promise and challenges" Authors: Liu Y, et al. Source:
Due to the widespread spread of adenovirus among people, a large part of the population has antibodies from previous infections, which neutralize the effect of adenovirus and reduce the success of gene therapies and vaccines. An attempt was made to overcome this problem by using chimp adenoviruses, which are similar enough to humans to infect human cells but, on the other hand, successfully avoid the action of existing antibodies.
Despite this, over 500 clinical trials using gene therapy have been conducted to date. A 16-month trial of lentivirus-based gene therapy for -thalassemia in France revealed that one patient did not require a blood transfusion. Another successful use of a lentiviral vector in clinical practice has been a recorded trial for the treatment of X-linked adrenoleukodystrophy due to ABCD1 gene deficiency. In this study, progressive cerebral demyelination in two patients was successfully blocked during the 14–16 months after lentiviral delivery of wild-type ABCD1 to CD34+ cells ex vivo. These results provided a good basis for the implementation of more clinical trials in the use of lentiviral vectors for gene therapy, but the limited duration of the therapy effect warranted further attempts to understand and improve it.
The first gene therapy drug, Vitravene (fomivirsen), was approved by the US Food and Drug Administration (eng. Food and Drug Administration, FDA) in 1998.It is a type of antisense oligonucleotide for local treatment of cytomegalovirus-induced retinitis in immunocompromised patients that is administered intraocularly by injection. Due to low demand for the drug, the manufacturer withdrew it from the European market in 2002. Year, and in the USA in 2006.
One of the first approved gene therapies in the world and the first approved in Europe, Glybera, rests on AAV. AAV vectors are currently used in more than 200 clinical studies for the treatment of a wide range of diseases and disorders worldwide. Recently, the treatment of genetically caused blindness has also started using the AAV-based medicine, Luxturna, and it is expected that the market will soon see the entry of another AAV-mediated gene therapy drug, also for the treatment of ophthalmological disorders, whose clinical trials are in the final phase. In recent years, the AAV-CRISPR/Cas9 system for in vivo genome editing has been developed, expanding therapeutic possibilities even further.
In conclusion, gene therapy is a rapidly advancing field that has the potential to revolutionize the way we treat a wide range of diseases, including cancer and immunological disorders. The use of viral vectors and CAR-T cells are some examples of promising therapies that are being developed in this field. Viral vectors, such as adenoviruses and lentiviruses, are a type of vehicle that scientists use to deliver therapeutic genetic material directly to cells in the body. Through the use of these vectors, researchers are developing new therapies that have the potential to specifically target cancer cells while leaving healthy cells unharmed.
On the other hand, CAR-T cell therapies are a type of immunotherapy that involve genetically modifying a patient's own T cells to recognize and attack cancer cells. This approach has shown significant promise in the treatment of blood cancers such as leukemia and lymphoma, with remission rates as high as 90% in some cases.
The ongoing research in this field is expected to bring new and more advanced therapies for different diseases and to improve the lives of patients suffering from cancer and immunological disorders. The continued advancements in genetic editing technology will also enable scientists to target and manipulate genetic material with more precision, which would open up new possibilities for the treatment of a wide range of diseases.
Josipa is QA Director and Principal GCP and GVP Auditor at Proqlea Ltd. She has over 18 years of experience in the pharmaceutical industry and is an acknowledged expert in the QA (Quality Assurance) field.
