Tumor immunotherapy: Rebuilding hope in fighting cancer and lighting up the light of life

Author: Zhou Jing, Shaanxi Cancer Hospital

Reviewer: Li Lina, Chief Physician, Shaanxi Cancer Hospital

In today's medical field, tumors (cancer) are still one of the major challenges threatening human health. However, with the rapid development of science and technology, especially the rise of tumor immunotherapy, our "arsenal" of weapons to fight tumors has been unprecedentedly expanded. Today, let us take a deeper look at this therapy - tumor immunotherapy, explore how it fights tumor cells, and bring new hope to cancer patients.

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1. Tumor: The "Invisible Killer" of Life

In simple terms, a tumor is a mass formed by abnormal growth of cells in the body. Tumor cells lose the control of normal cell growth and differentiation, can proliferate without limit and may invade surrounding tissues, and even spread to other parts of the body through the blood or lymphatic system. The formation of tumors is often caused by a combination of factors, including genetic factors, environmental factors, and lifestyle. This disease has a high mortality rate and can be called an "invisible killer" of life.

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2. How do tumor cells break through the immune system’s “natural defense line”?

In the complex ecosystem of the human body, the immune system plays a vital role. Like a well-trained army, it patrols our bodies at all times, identifying and removing foreign bodies marked as "non-self", including viruses, bacteria and cells with early lesions. Under normal circumstances, the immune system can identify and remove tumor cells, but "cunning" tumor cells can evade the surveillance and attack of the immune system through a variety of strategies, such as disguising themselves and inhibiting the activity of immune cells, so that they can continue to proliferate in the body.

3. Tumor immunotherapy: restarting the “war against cancer”

It is precisely based on this "cat and mouse game" between tumor cells and the immune system that tumor immunotherapy came into being. It aims to restore the body's normal anti-tumor immune response by restarting and maintaining the tumor immune cycle, thereby achieving the purpose of controlling or even eliminating tumors. Unlike traditional therapies such as surgery, radiotherapy, and chemotherapy, immunotherapy does not directly act on the tumor cells themselves, but fights cancer by activating or enhancing the patient's own immune system. Therefore, it has a more lasting therapeutic effect.

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IV. Three Pillars of Immunotherapy

1. Immune checkpoint inhibitors: This is one of the most widely used immunotherapy methods in clinical practice. Immune checkpoints are a series of regulatory mechanisms within the immune system that are used to prevent autoimmune diseases caused by excessive activation of immune responses. However, tumor cells use these immune checkpoints to inhibit the activity of immune cells. Immune checkpoint inhibitors can block these inhibitory signals, thereby removing the "brakes" of tumor cells on the immune system, allowing immune cells to re-launch a fierce attack on tumor cells.

2. Adoptive cell therapy: represented by chimeric antigen receptor T cell therapy (CAR-T cell therapy), this is a highly personalized treatment method. First, T lymphocytes (an important immune cell) are isolated from the patient's body, and then genetically modified in the laboratory to introduce genes encoding chimeric antigen receptors (CARs) so that they can specifically recognize and kill tumor cells. Finally, a large number of modified T cells cultured in vitro are re-injected into the patient's body, making them "super warriors" against tumors.

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3. Tumor vaccine: As the name implies, tumor vaccine is a method of stimulating the body to produce a specific immune response by injecting a vaccine containing tumor antigen genes or tumor antigen peptides. Although the research and development of tumor vaccines is still in its early stages, it has great potential and is expected to become an important direction for future tumor immunotherapy.

5. Advantages and Challenges of Immunotherapy

Compared with traditional therapies, immunotherapy has significant advantages. First, it can produce lasting responses in the body, giving patients a chance of long-term survival. Second, immunotherapy has a wide range of indications and is suitable for the treatment of various types of tumors. However, immunotherapy is not a panacea. During the treatment process, patients may experience delayed responses and pseudoprogression. Pseudoprogression refers to the fact that the tumor appears to increase in a short period of time, but in fact it is a manifestation of immune cells gathering in large numbers and preparing to attack the tumor, which is related to the delayed effect of immunotherapy. In addition, immunotherapy may also trigger a series of adverse reactions involving multiple organs and tissues throughout the body, such as the skin, thyroid, lungs, digestive tract, etc., which require close monitoring and timely intervention.

As an emerging treatment method, tumor immunotherapy is gradually changing our understanding and treatment of cancer. It gives us hope for cancer cure and brings new possibilities of survival to those desperate patients. However, we must also be aware that immunotherapy is not a universal "magic drug" and there are still many unsolved mysteries waiting for us to explore. In the future, we expect scientists to continuously break through technical bottlenecks, optimize treatment plans, and allow immunotherapy to benefit more cancer patients. At the same time, we also call on all sectors of society to pay more attention and support to tumor immunotherapy and jointly promote the rapid development of this technology.

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