Significant Reduction of Saccharomyces cerevisiae in the Gut Microbiota of Colorectal Cancer Patients from Iran

Backgrounds: This study aimed to investigate and compare the prevalence of Saccharomyces cerevisiae (S. cerevisiae) in the stool of colorectal cancer (CRC) patients and healthy controls.Materials & Methods: Over a one-year study period from April 2022 to April 2023, 25 patients who met all the necessary conditions for inclusion in the study were selected from among the patients referring to the colonoscopy unit of a teaching hospital in Tehran, considering the exclusion criteria. Stool samples were collected and immediately transported to the laboratory in a cold chain. Also, 25 healthy individuals who were matched with the patients in terms of sex, age, and ethnicity were included as a control group. After DNA extraction, the presence of S. cerevisiae was assayed by TaqMan real-time polymerase chain reaction (PCR) using specific primers and probe.Findings: The cancer stage of all individuals in the CRC group was 3, and the location of tumor formation in all of them was colon. Of the 25 samples in each group, three samples in the CRC group and 18 samples in the healthy group were positive for the presence of S. cerevisiae DNA. This difference was statistically significant (p< .0001).Conclusion: The results may indicate the importance of evaluating S. cerevisiae reduction as an indicator for the diagnosis of CRC. Considering the positive role of S. cerevisiae in maintaining gut health and also in helping treat CRC, it could be used as a probiotic product or adjuvant in this field.