P0503 - Profiling Gut Microbiota of Colorectal Cancer in Indonesia: A Focus on Beneficial Taxa Depletion

Yudith Annisa Rezkitha, MD¹, Amal Arifi Hidayat, MD¹, Irine Normalina, Dr¹, Ricky Indra Alfaray, MD, PhD¹, Priyo Budi Purwono, MD, PhD¹, MariaLucia Inge Lucida, MD, PhD¹, Isna Mahmudah, MD¹, Hasan Maulahela, MD, PhD², Husin Thamrin, MD¹, Yoshio Yamaoka, MD, PhD³, Muhammad Miftahussurur, MD, PhD¹
1Universitas Airlangga, Surabaya, Jawa Timur, Indonesia; 2Universitas Indonesia, Surabaya, Jawa Timur, Indonesia; 3Oita University, Yufu, Oita, Japan

Introduction: Regional differences in the gut microbiota and CRC incidence and mortality rates are well-documented. However, studies on the microbiota associated with CRC in Indonesia remain scarce. This study aimed to characterize the gut microbiota profile of CRC in Indonesia.

Methods: We collected stool samples from 14 patients with CRC (CRC), 19 patients with non-CRC bowel diseases (non-CRC), and 16 healthy controls (HC). The gut microbiota profiles across the three groups were analyzed using 16S rRNA gene amplicon sequencing. Data analysis was performed using several software packages: QIIME2, ANCOM-BC2, and PICRUSt2

Results: In comparison to the non-CRC and HC groups, patients with CRC demonstrated significant differences in both alpha and beta diversity. The CRC group had lower evenness and richness than the HC group. Firmicutes and Bacteroidota were identified as the predominant phyla across all groups. The differential abundance analysis identified five beneficial genera that were substantially reduced in Indonesian CRC patients: Roseburia, Dialister, Agathobacter, and Muribaculaceae. No genera were found to be significantly enriched in CRC. Functional prediction analysis revealed multiple pathways such as mTOR, mRNA surveillance, basal transcription factors, phagosome, and proteasome, were reduced in CRC. Conversely, CRC demonstrated a significant upregulation of pathways related to lipid metabolism and the biosynthesis of flavonoids, stilbenoids, diarylheptanoids, and gingerols.

Discussion: It is important to highlight those four depleted genera in the CRC group—Roseburia, Dialister, Agathobacter, and Muribaculaceae—have been shown to have anti-inflammatory and anti-tumorigenic properties. In our study, depletion of these four genera in CRC aligns with existing evidence suggesting their crucial role in maintaining gut health. The reduction in pathways identified by functional analysis may indicate disrupted cellular processes and impaired immune responses mediated by altered microbial community in CRC. Alterations in metabolic pathways may suggest changes in gut microbial metabolism and its effect on host metabolism. While numerous studies report increased abundance of harmful taxa in colorectal cancer, the loss of beneficial

Disclosures:
Yudith Annisa Rezkitha indicated no relevant financial relationships.
Amal Arifi Hidayat indicated no relevant financial relationships.
Irine Normalina indicated no relevant financial relationships.
Ricky Indra Alfaray indicated no relevant financial relationships.
Priyo Budi Purwono indicated no relevant financial relationships.
MariaLucia Inge Lucida indicated no relevant financial relationships.
Isna Mahmudah indicated no relevant financial relationships.
Hasan Maulahela indicated no relevant financial relationships.
Husin Thamrin indicated no relevant financial relationships.
Yoshio Yamaoka indicated no relevant financial relationships.
Muhammad Miftahussurur indicated no relevant financial relationships.

Yudith Annisa Rezkitha, MD¹, Amal Arifi Hidayat, MD¹, Irine Normalina, Dr¹, Ricky Indra Alfaray, MD, PhD¹, Priyo Budi Purwono, MD, PhD¹, MariaLucia Inge Lucida, MD, PhD¹, Isna Mahmudah, MD¹, Hasan Maulahela, MD, PhD², Husin Thamrin, MD¹, Yoshio Yamaoka, MD, PhD³, Muhammad Miftahussurur, MD, PhD¹. P0503 - Profiling Gut Microbiota of Colorectal Cancer in Indonesia: A Focus on Beneficial Taxa Depletion, ACG 2025 Annual Scientific Meeting Abstracts. Phoenix, AZ: American College of Gastroenterology.