Exome and Tissue-Associated Microbiota as Predictive Markers of Response to Neoadjuvant Treatment in Locally Advanced Rectal Cancer

作者：Isabella K. T. M. Takenaka, Thais Fernanda Bartelli, Alexandre Defelicibus, Juan M. Sendoya, Mariano Golubicki, Juan Robbio, Marianna Sampaio Serpa, Gabriela Pereira Branco, Luana B. C. Santos, Laura Carolina López Claro, Gabriel Oliveira dos Santos, Bruna Elisa Catin Kupper, Israel Tojal da Silva, Andrea S. Llera, Celso Abdon Lopes de Mello, Rachel P. Riechelmann, Emmanuel Dias‐Neto, Soledad Iseas, Samuel Aguiar, Diana Noronha Nunes · 发表于：Frontiers in Oncology · 年份：2022 · DOI：10.3389/fonc.2022.809441 · 被引用次数：13 · 研究领域：Colorectal Cancer Surgical Treatments、Colorectal Cancer Screening and Detection、Genetic factors in colorectal cancer

The clinical and pathological responses to multimodal neoadjuvant therapy in locally advanced rectal cancers (LARCs) remain unpredictable, and robust biomarkers are still lacking. Recent studies have shown that tumors present somatic molecular alterations related to better treatment response, and it is also clear that tumor-associated bacteria are modulators of chemotherapy and immunotherapy efficacy, therefore having implications for long-term survivorship and a good potential as the biomarkers of outcome. Here, we performed whole exome sequencing and 16S ribosomal RNA (rRNA) amplicon sequencing from 44 pre-treatment LARC biopsies from Argentinian and Brazilian patients, treated with neoadjuvant chemoradiotherapy or total neoadjuvant treatment, searching for predictive biomarkers of response (responders, n = 17; non-responders, n = 27). In general, the somatic landscape of LARC was not capable to predict a response; however, a significant enrichment in mutational signature SBS5 was observed in non-responders ( p = 0.0021), as well as the co-occurrence of APC and FAT4 mutations ( p < 0.05). Microbiota studies revealed a similar alpha and beta diversity of bacteria between response groups. Yet, the linear discriminant analysis (LDA) of effect size indicated an enrichment of Hungatella, Flavonifractor , and Methanosphaera (LDA score ≥3) in the pre-treatment biopsies of responders, while non-responders had a higher abundance of Enhydrobacter, Paraprevotella (LDA score ≥3)...