Microbial Allies: How Bacteria Support Cancer Treatment

Recent scientific discoveries reveal that bacteria associated with tumors play a significant role in influencing cancer progression and response to therapy. An international research team, led by scientists from the MRC Laboratory of Medical Sciences (LMS), Imperial College London, and the University of Cologne, uncovered that certain microbes found within tumor environments produce molecules capable of controlling tumor growth and enhancing the effectiveness of chemotherapy.

While most are familiar with microbes living on the skin or in the gut, studies now show that tumors also host unique bacterial communities. Researchers are exploring how these microbes can impact tumor development and treatment outcomes.

A breakthrough study published in Cell Systems identified a potent anti-cancer metabolite produced by bacteria associated with colorectal cancer. Through large-scale screening involving over 1,100 conditions in C. elegans (a model organism), scientists discovered that Escherichia coli bacteria produce a molecule called 2-methylisocitrate (2-MiCit). This molecule was found to improve the efficacy of the chemotherapy drug 5-fluorouracil (5-FU). Further analysis indicated that the tumor microbiome in patients could also produce 2-MiCit.

To validate these findings, experiments were conducted using human cancer cells and a fruit fly model of colorectal cancer. In both cases, 2-MiCit exhibited strong anti-cancer properties, with the fly model showing increased survival rates. The molecule functions by inhibiting a key mitochondrial enzyme in cancer cells, leading to DNA damage and activating pathways that hinder tumor growth. When combined with 5-FU, this approach significantly enhanced cancer cell death, demonstrating a synergistic effect.

Professor Filipe Cabreiro, a lead researcher from LMS, explained that these findings illuminate the chemical dialog between bacteria and cancer cells. "We now understand that bacterial chemicals can serve as powerful allies in cancer therapy, disrupting cancer cell metabolism and making tumors more vulnerable to treatment."

In collaboration with medicinal chemists, the team also optimized the natural compound, creating a synthetic version that proved even more effective at killing cancer cells. This paves the way for developing new drugs based on microbial metabolites.

These insights emphasize the importance of considering the tumor microbiome in personalized medicine. By understanding and harnessing bacterial metabolites like 2-MiCit, future cancer treatments could become more targeted and effective. The research highlights the intricate relationship between microbes and cancer, opening new avenues for therapeutic strategies.

source: https://medicalxpress.com/news/2025-09-microbial-allies-bacteria-cancer.html