Effect of Chemotherapy on Abundance in Colorectal Cancer Patients: A Study on Relapsing Patients.

Unlabelled: An intricate relationship exists, and interactions occur between the gut microbiota and colorectal cancer (CRC). Recent studies have indicated that inflammatory reactions stimulated by () lead to the development of CRC. Radical surgery combined with adjuvant chemotherapy is the primary treatment approach for most CRC patients. This study was designed to evaluate the abundance of as part of the gut microbiota in patients with CRC compared to healthy individuals and to assess the effect of the gut microbiota on patients undergoing adjuvant chemotherapy and those experiencing CRC relapse. There were 201 participants, comprising 50 healthy controls and 151 CRC patients. Stool samples were collected from three CRC groups (postoperatively, chemotherapy and relapse), and the fourth was the healthy control group. The amount of in each sample was analyzed using quantitative loop-mediated isothermal amplification-phenol red (QLAMP-PhR), a novel biomolecular method that targets regions encoding the specific gene. Compared with healthy control stool samples, the levels were significantly elevated in all CRC patient groups ( < 0.001), and it was significantly more frequent in the CRC relapse patients (group C) ( < 0.001). In addition, abundance increased significantly in the distal colon compared to the proximal colon ( < 0.001). Both CRC relapse and chemotherapy exert significant reciprocal effects on the gut microbiota of CRC patients. Microbiota-based intervention may be beneficial for patients during postoperative care, especially in CRC relapsing cases. : This study of the clinical trial has been registered in the ISRCTN registry with study registration number ISRCTN53358464. https://www.isrctn.com/ISRCTN53358464.

Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-024-01279-6.