Revolution in Oncology: How the Immune System Learns to Fight Cancer

Discover how groundbreaking advances in cancer immunotherapy are training our body's natural defenses to combat malignant cells.

Immunotherapy Oncology Cancer Research

Introduction

Imagine that our own body possesses a powerful internal weapon against cancer — a sophisticated system capable of recognizing and destroying malignant cells. Until recently, this seemed like science fiction, but today, oncoimmunology is turning this dream into reality 1 .

After a period of stagnation, oncology has found "new breath" and in the last 20-25 years has been enriched with knowledge that can truly be called revolutionary 1 . At the intersection of oncology and immunology, innovative treatment methods are emerging that are radically changing approaches to the therapy of malignant diseases.

Immune Defense

Harnessing the body's natural defense mechanisms to fight cancer cells.

Targeted Therapy

Precisely targeting cancer cells while sparing healthy tissues.

Impressive Results

Showing promising outcomes in clinical practice for various cancers 2 .

Key Concepts and Theories in Oncoimmunology

The Anti-Tumor Immune Cycle

At the core of immunotherapy lies the concept of the "anti-tumor immune cycle" — a cascade of processes responsible for the immune system's response to tumor cells 2 . This cycle includes several key stages:

Recognition

Detection of tumor antigens by immune cells

Activation

Triggering of specific immune response

Migration

Direction of immune cells to the tumor site

Infiltration

Penetration into the tumor microenvironment

Destruction

Elimination of cancer cells

Tumor Immune Evasion Mechanisms

Cancer cells are masters of disguise. They can "hide" from the immune system using various strategies:

Cancer cells express inhibitory molecules that suppress T-lymphocyte activity, effectively putting "brakes" on the immune response.

Tumors create an environment rich in regulatory T-cells and tumor-associated macrophages that suppress immune activity.

Cancer cells change their surface proteins, making them less "visible" to the immune system.
Major Types of Immunotherapy

Modern oncoimmunology focuses on two well-studied types of immunotherapy 2 :

  • Checkpoint inhibitors - Increase the activity of existing immune cells by reducing inhibitory signals
  • Adaptive cell therapy - Compensates for the lack of active immune cells directed against the tumor

Comparison of Major Immunotherapy Types in Oncology

Type of Therapy Mechanism of Action Examples Advantages Limitations
Checkpoint Inhibitors Blocking inhibitory signals in immune synapses Nivolumab, Ipilimumab Broad spectrum of action across various tumors Risk of autoimmune complications
Adaptive Cell Therapy Administration of artificially activated immune cells CAR-T therapy High specificity Complex manufacturing, high cost
Cytokine Therapies Systemic activation of immune response Interleukin-2 (Roncoleukin®) Approved for use since 1995 Toxicity with systemic administration

Detailed Analysis of Key Experiment: Combined Immunotherapy in Melanoma

Background and Hypothesis

One of the turning points in oncoimmunology was the study of combination therapy for metastatic melanoma — an aggressive form of skin cancer with an extremely poor prognosis. Researchers hypothesized that a combination of two checkpoint inhibitors — nivolumab (anti-PD-1) and ipilimumab (anti-CTLA-4) — would be more effective than monotherapy, as these drugs act on different stages of T-lymphocyte activation 2 .

Methodology

The study was conducted as a randomized controlled trial with participants having untreated melanoma without BRAF mutation. The experimental protocol included:

  • Participant enrollment: 945 patients randomly assigned to three groups
  • Treatment regimens: Three different therapy combinations
  • Evaluation criteria: Overall survival, progression-free survival, objective response rate

Efficacy Results

Efficacy Parameter Nivolumab + Ipilimumab Nivolumab Ipilimumab
Overall Survival (12 months) 73% 65% 53%
Objective Response Rate 58% 44% 19%
Complete Response 19% 12% 5%
Median PFS (months) 11.7 6.9 2.9

Safety Profile

Adverse Event Nivolumab + Ipilimumab Nivolumab Ipilimumab
Any Grade 3-4 Side Effects 59% 21% 28%
Colitis 13% 2% 9%
Increased ALT/AST 13% 4% 2%
Diarrhea 12% 3% 8%

Scientific Significance

This study became an important milestone in oncoimmunology for several reasons:

1

Confirmed hypothesis about synergism of different immunotherapeutic approaches

2

Demonstrated possibility of achieving long-term remissions in metastatic melanoma

3

Highlighted importance of balance between efficacy and toxicity

4

Stimulated development of biomarkers for predicting response and toxicity

The results of this research led to regulatory approval of the nivolumab and ipilimumab combination for melanoma treatment and changed the standards of therapy for this disease.

Scientist's Toolkit: Key Reagents in Oncoimmunology

Modern oncoimmunology relies on a sophisticated arsenal of research tools. Here are the main categories of reagents and materials used in this field:

Monoclonal Antibodies

Used both for therapy (checkpoint inhibitors) and for research on immune response mechanisms. Therapeutic antibodies block inhibitory signals (PD-1, CTLA-4) or activate stimulating receptors on immune cells.

Recombinant Cytokines

Proteins that regulate the growth and activity of immune cells. Interleukin-2 (IL-2) is one of the first cytokines used in cancer immunotherapy. The drug Roncoleukin® (recombinant human interleukin-2) has been approved for use since 1995 and demonstrates effectiveness in various diseases 3 .

Immune Cell Cultures

T-lymphocytes, NK cells, and dendritic cells are used to study immune response mechanisms and develop adaptive cell therapies. Improving methods for expanding and activating these cells ex vivo is a key research direction.

Model Systems

Include transgenic mice with human immune systems, organoids, and 3D cultures that reproduce complex interactions in the tumor microenvironment. Modern models increasingly adequately mimic human immune responses, improving the predictive value of preclinical studies.

Reagents for Immune Response Monitoring

Flow cytometry and immunohistochemistry allow assessment of tumor immune cell infiltration, checkpoint molecule expression, and lymphocyte activation status. The developing "Immunoscore" — a system for quantitative assessment of immune response in tumors — has the potential to become an important prognostic tool .

Flow Cytometry

Quantitative analysis of cell populations

Immunohistochemistry

Spatial analysis of immune cell distribution

Immunoscore

Quantitative assessment of immune response

Conclusion: Prospects and Challenges

Oncoimmunology is experiencing a golden era of discoveries, but it faces serious challenges. Resistance to therapy remains a significant problem — even with the most modern approaches, some patients do not respond to treatment . Resolving this issue requires a deeper understanding of resistance mechanisms and the development of strategies to overcome them.

Promising Directions

Combination Approaches

Various immunotherapeutic combinations to enhance anti-tumor response

Personalized Immunotherapy

Using genomic profiling and biomarkers for treatment selection

Microbiome Research

Investigating the influence of microbiome on immunotherapy efficacy

Innovative Cell Therapies

Using not only T-cells but also NK cells and macrophages

Expert Insight

"A cure for cancer may be an unrealistic goal, but achieving long-term disease control is becoming an increasingly achievable task" .

Oncoimmunology offers a fundamentally new approach to cancer treatment based on mobilizing the body's internal resources. With continued research and method refinement, immunotherapy promises to become even more effective and accessible for patients with various types of malignant diseases.

United Immunology Forum in Novosibirsk (2019)

Became an important milestone in the exchange of knowledge and ideas in this rapidly developing field, contributing to further progress in the fight against oncological diseases.

References