How Microbes Shape Tumor Growth

Did you know tiny germs can live inside a tumor? The tumor microbiome is a small ecosystem of bacteria, viruses, and fungi that remain within the tumor. These minute germs respond to cancer cells and to the immune system. Due to this, they can alter the onset, rate of growth of a tumor, its rate of spreading, and its response to treatment. 

The role of fungi

The role of fungi in cancer is a new and emerging research area. Some species of Candida and Malassezia are detected in many tumor types, like oral, esophageal, gastrointestinal, and pancreatic cancers. This inflammatory shift helps cancer cells survive and multiply. 

Viral influence and oncogenesis

Viral influence drives tumor development with some viruses, like HPV, HBV/HCV, and Epstein-Barr Virus (EBV). These viruses account for a significant portion of cancer cases worldwide. Oncogenic viruses promote tumor growth by inserting their genetic material into human cells, leading to proteins that disrupt cell-cycle control and allow unchecked growth. 

How do bacteria affect tumor metabolism?

Bacteria make up a major part of the tumor microbiome, and their interactions with cancer cells are complex.

Some bacteria can:

• Change the body’s metabolism.
• Activate chemotherapy drugs into more toxic forms.
• Break down chemotherapy drugs, making them less effective.
• Produce metabolites like short-chain fatty acids that influence inflammation and cell growth.

These effects can weaken the immune system, encourage new blood vessel formation, and support tumor spread.

What are the treatment suggestions?

Microbes are the active participants in cancer development, and there are many suggestions for treatment. Understanding how microbes interact with tumors is helping researchers develop new treatment strategies:

• Microbiome modulation: This includes using antibiotics, probiotics, or fecal microbiota transplants to reshape the microbiome and improve treatment response.
• Microbial metabolites: This includes creating medicines that block harmful signals released by microbes.
• Microbial diagnostics: This includes using microbial patterns inside tumors to diagnose cancer or predict how it may behave.

Exploring the tumor microbiome is a fast-growing area of cancer research that may lead to more effective treatments and better patient outcomes.