Outside the operating room, a precious tumor sample is being carefully preserved - it may hold the key to conquering cancer.
In the long journey to combat cancer, scientists need not only advanced technology and theories but also precious research materials - tumor samples. Tumor banks have emerged in response to this need, functioning like a special "financial bank" that stores not currency but core assets in the fight against cancer: tumor tissues, blood samples, and related clinical data1 .
In the era of precision medicine, these high-quality biological samples have become indispensable strategic resources for advancing cancer research, providing a solid material foundation for both basic research and clinical translational medicine.
Simply put, a tumor bank is a systematic collection, storage, and management resource repository for tumor samples and related clinical data. These samples include surgically removed tumor tissue, paired normal tissue, blood/plasma samples, and molecules such as nucleic acids and proteins extracted from these samples1 .
Similar to how modern banks provide clients with professional asset management, tumor banks provide researchers with high-quality biological sample and data management services.
Since the late 1990s, medical institutions and research units worldwide have established tumor banks. For example, the Wuxi Tumor Bank collected 3,138 specimens between December 1999 and December 2003, covering 37 disease types/pathological types of benign and malignant tumors1 .
These resources serve not only local research but also support broader research fields - this bank has provided 320 specimens to institutions inside and outside the city for DNA, RNA, and protein-related studies1 .
Establishing a qualified tumor bank is no easy task; it is a systematic project involving multiple disciplines and processes.
Sample collection is the first and most critical step. In clinical practice, it must be ensured that sample collection does not affect the patient's normal diagnosis and treatment6 . After surgical resection, tumor samples must first be evaluated by pathology department physicians, and only the remaining portion after meeting clinical diagnostic requirements can be used for research6 .
The sample processing and preservation环节 is particularly critical. Different research purposes require different preservation conditions: samples for molecular biology research are typically cryopreserved at deep low temperatures of -80°C or in liquid nitrogen1 ; while samples for morphological research may be made into paraffin blocks or placed in specific preservation solutions6 .
With the development of precision medicine, information management has become a core feature of modern tumor banks. Advanced tumor banks are equipped with professional information management systems with functions including: patient clinical data, follow-up information, auxiliary examination information, specimen basic information, specimen storage location coordinates, specimen use and disposal management1 .
To ensure sample quality, especially for samples used for RNA extraction, they need to be placed in specialized RNA sample preservation solutions to prevent degradation6 .
Quality is the lifeline of tumor banks. Samples without quality assurance cannot support valuable research and may even lead to erroneous scientific conclusions.
Focuses more on standardization of collection and processing procedures, minimizing the impact of environmental and temperature factors on samples6 .
| Sample Type | Common Preservation Methods | Main Applications | Precautions |
|---|---|---|---|
| Tumor Tissue | -80°C deep freezing, liquid nitrogen | DNA/RNA extraction, protein analysis | Rapid freezing to prevent ice crystal formation |
| Blood Sample | -80°C deep freezing | Plasma protein analysis, cell-free nucleic acid testing | Secondary high-speed centrifugation to reduce white blood cell DNA contamination |
| Lymphocytes | Liquid nitrogen preservation | Immunology research, genetic analysis | Specific separation procedures |
| Nucleic Acid Samples | -80°C deep freezing | Molecular biology research | Aliquot storage to avoid repeated freeze-thaw cycles |
The best way to understand the value of tumor banks is through a real research case. A 2025 study published in Cell by Chenli Liu's team at the Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, and Yichuan Xiao's team at the Shanghai Institute of Nutrition and Health perfectly demonstrates how tumor samples drive scientific breakthroughs4 .
The research team used Salmonella as chassis cells to construct a synthetic bacterial strain that can efficiently survive and proliferate in tumor tissue while being rapidly cleared in normal tissue4 .
They tested the therapeutic effects of this synthetic bacteria in various disease animal models including colon cancer, melanoma, and bladder cancer4 .
Through quantitative research methods, the team discovered that interleukin-10 receptor (IL-10R) is highly expressed on various immune cells in tumors, including CD8+ T cells, macrophages, and neutrophils, and demonstrated that this characteristic is indispensable for immune cells to exert anti-tumor effects under bacterial mediation4 .
This research first revealed that IL-10R expression on immune cell surfaces exhibits a "hysteresis effect"4 . This means that when immune cells receive high concentrations of IL-10 stimulation, they form a memory effect, and even if subsequent IL-10 concentrations decrease, IL-10R expression can remain at high levels4 .
Utilizing this mechanism, synthetic bacteria can stimulate macrophages within tumors to produce more IL-10 by binding to Toll-like receptor 4 (TLR4), thereby activating "dormant" immune cells in tumors - tissue-resident memory CD8+ T cells, restoring their ability to kill tumor cells4 .
| Discovery Content | Mechanism | Significance |
|---|---|---|
| IL-10R Hysteresis Effect | After high concentration IL-10 stimulation, IL-10R expression maintains high levels | Explains the maintenance mechanism of tumor immune cell characteristics |
| Synthetic Bacteria Targeting Mechanism | Differential growth in tumor and normal tissues | Achieves tumor-specific targeting |
| Immune Cell Activation | Stimulates macrophages to produce IL-10 via TLR4 | Activates "dormant" CD8+ TRM cells |
| Immune Escape Mechanism | IL-10 reduces movement ability of tumor-associated neutrophils | Slows intra-tumoral bacterial clearance |
This discovery not only answers the key scientific question that has plagued the field of bacterial tumor therapy - "why can bacteria activate 'anti-tumor immunity' while evading 'anti-bacterial immunity'" - but also provides important guidance for rational design of new-generation synthetic bacterial therapies4 .
Modern tumor research relies on a series of precise reagents and technical means. Here is a梳理 of key research reagents and their functions:
| Research Reagent/Technology | Main Functions | Application Fields |
|---|---|---|
| Synthetic Bacterial Therapy | Targets tumors, regulates immune microenvironment | Solid tumor immunotherapy |
| Tumor-Infiltrating Lymphocyte (TIL) Therapy | Utilizes patient's own T cells to attack tumors | Advanced melanoma treatment |
| Bispecific Antibodies | Connects tumor antigens and T cell stimulating molecules | Various blood tumors and solid tumors |
| Personalized mRNA Vaccines | Stimulates tumor-specific immune responses | Melanoma adjuvant therapy |
| Immune Checkpoint Inhibitors | Blocks immune suppression signals | Various advanced cancers |
| Tissue Preservation Solutions (e.g., RNA preservation solution) | Maintains nucleic acid integrity, prevents degradation | Biobank construction, molecular research |
Sample distribution across different cancer types in a typical tumor bank
Although tumor bank construction has made significant progress, it still faces many challenges. Structured integration of clinical information is currently one of the biggest difficulties6 .
Future tumor banks will no longer be merely sample repositories, but integrated platforms combining sample resources, clinical data, molecular information, and research results. Scientists can access required samples and information through standardized data interfaces, just like查阅文献 in a library, accelerating every step of cancer research.
As more samples accumulate and technology advances, this special "bank" will contribute irreplaceable value to humanity's ultimate victory over cancer.