Introduction: A New Era in Cancer Treatment
For decades, cancer treatment primarily relied on traditional therapies such as surgery, chemotherapy, and radiation. Although these techniques have saved many lives they are not without their downsides, such as substantial side effects and the inability to specifically target certain types of cancer. The prestige of immunotherapy has arrived at a new era of cancer therapy, providing more personalized, more accurate, and more tolerable strategies against cancer. Immunotherapy leverages the patient’s immune system to identify and fight against cancer cells, a promising advancement in cancer treatment.
This article discusses the development of immunotherapy and how it is, the various immunotherapy modes that it performs, the success to date with immunotherapy, and the road ahead for using such an advanced treatment for cancer.
What is Immunotherapy?
Immunotherapy is a therapy that utilizes and strengthens systemic innate immune function in which to attack cancer. The immune system is able to identify and kill damaging agents, such as viruses infections, bacteria, as well as cancer cells. Cancer cells, on the other hand, can acquire the ability to escape immune surveillance and proliferate smolderingly.
Immunotherapies target increasing the activity or effectiveness of the immune system, or by providing the immune system with parts, like antibodies, that can facilitate the identification and elimination of cancer cells. In contrast to conventional therapy, which specifically targets cancer cells, immunotherapy is geared towards enhancing the immune system’s ability to better combat cancer.
Immunotherapy for Cancer: The History and Evolution of Immunotherapy
Early Beginnings: The Foundation of Immunotherapy
The idea of cancer therapy with the immune system has been coming back for over a century. The early pioneer, William Coley, is commonly regarded as the grandfather of immunotherapy. In the 1890s Coley observed the beginning of a spontaneous regression of tumor for some of the cancer patients who developed infection. He predicted that the immune response of the body to infection, which attacks infection, may attack cancer as well. Coley himself started to use a combination of bacterial toxins in the treatment of cancer patients although that practice was not popular at that time.
Immunotherapy for Cancer: Modern Immunotherapy – A Shift Towards Precision
The real innovation to modern immunotherapy started at the end of the 20th century with the identification of monoclonal antibodies, artificial molecules that are purposely made to interact with a particular cell. The manipulations of the immune system became ever more refined during the 1990s, resulting in approval for the use of the interferon in the treatment of melanoma and kidney cancer, followed by the first successful immune checkpoint inhibitor, Ipilimumab (Yervoy) in 2011.
The approval of Ipilimumab initiated a new era for immunotherapy and may be used to treat a wider spectrum of tumor diseases by targeted immune attack.
Immunotherapy for Cancer: Types of Immunotherapy
Immunotherapy has become various types, each of which addresses different points within the immune system versus different kinds of tumors. Some of the most common forms include:-
Immune Checkpoint Inhibitors
Immune checkpoint inhibitors are a new generation of medicine that has changed cancer treatment by suppressing the “brakes” of the immune system, in order that it would be able to attack cancer cells now in a more robust manner. Malignant cells frequently employ checkpoint proteins (e.g., PD-1, PD-L1, CTLA-4) to avoid immune monitoring. By inhibiting these proteins, immune checkpoint inhibitors can enhance the immune system’s response to cancer.
Examples of checkpoint inhibitors include:-
Pembrolizumab (Keytruda) and Nivolumab (Opdivo) – Drugs against PD-1 protein that enable the T-cell to identify and kill cancer cells.
Ipilimumab (Yervoy) – Selective CTLA-4 and has demonstrated clinical activity for the treatment of melanoma and other carcinomas.
CAR-T Cell Therapy
Chimeric Antigen Receptor T-cell (CAR-T) therapy is a transformative therapeutic technology, wherein the patient’s own T-cells are engineered to more effectively target and destroy cancer cells. This therapy is particularly effective in blood cancers such as leukemia and lymphoma. In CAR-T therapy, T-cells are removed from the patient’s blood, engineered in a laboratory to express receptors specific to the cancer cells, and then infused back into the patient. These re-engineered cells are then more suitable to discriminate and destroy cancer.
Monoclonal Antibodies
Laboratories design monoclonal antibodies as therapeutics that recognize particular antigens on the surface of cancer cells. These antibodies can either directly eliminate cancer cells or mark them for the immune system’s elimination. They can also be conjugated to toxic drugs or radioisotopes to provide more specific therapy.
For example: –
Trastuzumab (Herceptin) binds to the HER2 protein present in certain breast cancers and has significantly enhanced survival in those patients.
Rituximab (Rituxan) binds to CD20 protein on B cells and doctors administer it to treat non-Hodgkin lymphomas.
Oncolytic Virus Therapy
Oncolytic virus therapy is a treatment that utilizes genetically engineered viruses that selectively kill cancer cells. virus therapy selectively infects and replicates within cancer cells, causing their death. This process not only kills cancer cells but also stimulates the immune system to target and eliminate cancer throughout the body. Clinical trials have shown efficacy in treating solid tumors like melanoma and glioblastoma.
Cancer Vaccines
preventive vaccines and therapeutic vaccines.
Preventive vaccines: The HPV vaccine inhibits the infection with human papillomavirus and subsequent cervical and other cancers.
Therapeutic vaccines: Scientists design these vaccines to treat existing cancers by stimulating the immune system to recognize and attack tumor cells. An example is Bacillus Calmette-Guerin (BCG) for the treatment of bladder cancer.
Immunotherapy for Cancer: Success Stories of Immunotherapy
Immunotherapy has resulted in some of the most encouraging achievements in cancer therapy, in particular cancers that were very hard to treat.
Melanoma
Melanoma, as a skin cancer, is one of the cancers so far with impressive advances using immunotherapy. Researchers have reported excellent survival rates for drugs such as Pembrolizumab (Keytruda) and Nivolumab (Opdivo), even in advanced melanoma patients.
These treatments have allowed patients with advanced melanoma to live longer and with fewer side effects compared to traditional chemotherapy.
Lung Cancer
LUNG CANCER, Especially NON-SMALL CELL LUNG CANCER (NSCLC), has also improved due to immunotherapy. Researchers are expanding immunotherapy to more cancers and combining it with other treatments.
Hodgkin Lymphoma
Immunotherapy has also cured Hodgkin lymphoma, a malignancy of the lymphatic system. Nivolumab and Pembrolizumab have been successful with patients with relapsed/refractory Hodgkin Lymphoma, providing new hope where conventional chemotherapy had failed.
Challenges and Limitations
Although immunotherapy presents immense opportunities, it is not without problems. Some of the primary limitations include:-
Side effects: Despite being milder than conventional therapies, immunotherapy can still have side effects (for example, fatigue, skin rash, immune-related adverse events in which the immune system harms surrounding healthy tissue).
Not effective for all patients: A number of patients are unresponsive to immunotherapy, and researchers must determine who will respond to immunotherapy.
High cost: Immunotherapy drugs are costly and thus inaccessible to many patients, especially in low- and middle-income countries.
Immunotherapy for Cancer: The Future of Immunotherapy
The future of immunotherapy is hopeful, with continuing research on how to better optimize its benefit and accessibility.
Researchers are expanding immunotherapy to more cancers and exploring immune combination therapies with chemotherapy, targeted therapy, and radiation. Furthermore, researchers are devising increasingly individualized designs to individualize immunotherapy with regard to a patient’s genetic background and tumoural properties.
Emerging AI and machine learning will enhance immunotherapy by recommending the best treatments for individual patients.
Conclusion: Precision at the Forefront of Cancer Treatment
Immunotherapy has revolutionized cancer treatment, offering more effective, targeted therapies with fewer side effects than traditional treatments. As the field continues to evolve, the potential for curing or controlling previously untreatable cancers becomes more achievable. As precision medicine advances, immunotherapy for cancer will lead treatment, transforming oncology and offering hope to millions worldwide.
