How does the immune system recognize and destroy cancer cells through immunotherapy?

The immune system is our body’s natural defense mechanism that protects us from infections, viruses, and abnormal cells like cancer. It works through a network of white blood cells, mainly T cells, which detect and attack anything that seems harmful. However, cancer cells are clever — they can hide from the immune system by mimicking normal cells or producing signals that suppress immune activity. Immunotherapy helps overcome these barriers by training and empowering the immune system to identify and destroy cancer cells more effectively.

Role of the Immune System

• The immune system recognizes harmful invaders through antigens, which are unique proteins found on the surface of cells.

• When a T cell detects abnormal antigens, it activates an immune response to kill the infected or damaged cell.

• Cancer cells often develop mechanisms to avoid detection — for example, by producing proteins that deactivate T cells or by creating an immune-suppressive environment around the tumor.

• Immunotherapy helps reprogram the immune system so that it can detect these hidden cancer cells and eliminate them.

How Immunotherapy Boosts the Immune Response

There are different types of immunotherapy treatments, each with its own way of helping the immune system fight cancer. Consulting an experienced Immunotherapy Cancer Treatment Doctor Delhi can help patients understand which therapy suits their condition best and how it can enhance treatment outcomes.

• Checkpoint inhibitors: These drugs block checkpoint proteins (like PD-1 or CTLA-4) that normally stop T cells from attacking healthy cells. Cancer cells exploit these checkpoints to escape attack. When these checkpoints are blocked, T cells are “unlocked” and can identify and destroy cancer cells.

• Monoclonal antibodies: These are lab-made proteins designed to attach to specific antigens on cancer cells. Once attached, they mark cancer cells for destruction or deliver targeted treatments directly to them.

• Cancer vaccines: These vaccines train the immune system to recognize and fight cancer-specific antigens. They act as a trigger, prompting the immune system to attack cells with those markers.

• CAR T-cell therapy: In this advanced therapy, a patient’s own T cells are collected and genetically modified to create special receptors (CARs) that recognize cancer cells. When reintroduced into the body, these supercharged T cells can aggressively hunt and kill cancer cells.

• Cytokine therapy: Cytokines like interleukins and interferons are proteins that boost immune cell activity. Administering them strengthens the immune response against tumors.

How Cancer Cells Are Destroyed

• Once T cells recognize cancer cells as harmful, they multiply and surround the tumor.

• They release enzymes and chemicals that damage the cancer cell membrane and trigger apoptosis, which means programmed cell death.

• The immune system also develops memory, allowing it to recognize and respond faster if the same type of cancer reappears in the future.

Why Immunotherapy Is a Breakthrough

• Immunotherapy works by enhancing the body’s natural defense instead of directly killing cells like chemotherapy or radiation.

• It specifically targets cancer cells while minimizing harm to normal cells.

• The immune memory it creates offers long-term protection, reducing the chances of recurrence.

• Although not every patient responds equally, many have experienced remarkable recoveries, even in advanced cancer stages.

In summary, immunotherapy has transformed cancer care by turning the immune system into a precise and powerful weapon. It helps T cells recognize, attack, and remember cancer cells, offering a smarter and longer-lasting approach to cancer control. Consulting an experienced Immunotherapy Cancer Treatment Surgeon RGCIRC (Rajiv Gandhi Cancer Institute and Research Centre) can help patients access the most advanced immunotherapy options and receive specialized care tailored to their cancer type and stage.