我国科学家首次揭示瘤内细菌调控肿瘤复发新机制

Core Insights - The research team at Westlake University has revealed that intratumoral bacteria have a dual role in regulating tumor immunity, providing a new perspective for cancer recurrence prevention and treatment [1][3] Group 1: Research Findings - The study indicates that tumors can be classified into "hot tumors," which are immune-activated, and "cold tumors," which are immune-suppressed, affecting patient response to immunotherapy [1] - The presence of intracellular bacteria significantly increases the recurrence rate of breast cancer, with a recurrence rate of 65% when bacteria are present, dropping to 6.7% after their removal [3] - In a preclinical postoperative recurrence model, mice with strong bacterial invasion signals showed an 80% recurrence rate, which decreased to 20% after the elimination of intracellular bacteria [3] Group 2: Mechanisms of Action - Intracellular and extracellular bacteria have distinctly different effects on immune regulation; while both induce neutrophil accumulation, intracellular bacteria convert them into immune-suppressive cells, whereas extracellular bacteria promote them as "anti-cancer warriors" [4] - The study found that live intracellular bacteria activate specific signaling pathways in tumor cells, leading to the secretion of IL-17B, which suppresses T cell function and promotes tumor recurrence [4] - This research suggests that intratumoral bacteria are not merely accompanying flora but are critical biological factors influencing tumor progression, opening new avenues for cancer treatment by potentially manipulating the growth and function of these bacteria [4]