Gut microbiota is associated with response to 131I therapy in patients with papillary thyroid carcinoma
Lei Zheng, Linjing Zhang, Li Tang, Dingde Huang, Deng Pan, Wei Guo, Song He, Yong Huang, Yu Chen, Xiao Xu, Bo Tang, Jing Chen
Abstract
Abstract Purpose Radioactive iodine ( 131 I) therapy is a conventional post-surgery treatment widely used for papillary thyroid carcinoma (PTC). Since 131 I is orally administered, we hypothesize that it may affect gut microbiome. This study aims to investigate alterations of intestinal microbiome caused by 131 I therapy in PTC patients and explore its association with response to 131 I therapy. Methods Fecal samples of 60 PTC patients pre- and post- 131 I therapy were collected to characterize the 131 I therapy-induced gut microbiota alterations using 16S rRNA gene sequencing. According to the inclusion criteria, sequence data of 40 out of the 60 patients, divided into excellent response (ER) group and non-excellent response (NER) group, were recruited to investigate the possible connection between gut microbiota and response to 131 I therapy. Multivariate binary logistic regression was employed to construct a predictive model for response to 131 I therapy. Results Microbial richness, diversity, and composition were tremendously altered by 131 I therapy. A significant decline of Firmicutes to Bacteroides (F/B) ratio was observed post- 131 I therapy. 131 I therapy also led to changes of gut microbiome-related metabolic pathways. Discrepancies in β diversity were found between ER and NER groups both pre- and post- 131 I therapy. Furthermore, a predictive model for response to 131 I therapy with a p value of 0.003 and an overall percentage correct of 80.0% was established, with three variables including lymph node metastasis, relative abundance of g_Bifidobacterium and g_Dorea. Among them, g_Dorea was identified to be an in independent predictor of response to 131 I therapy ( p = 0.04). Conclusion For the first time, the present study demonstrates the gut microbial dysbiosis caused by 131 I therapy in post-surgery PTC patients and reveals a previously undefined role of gut microbiome as predictor for 131 I ablation response. G_Dorea and g_Bifidobacterium may be potential targets for clinical intervention to improve response to 131 I in post-operative PTC patients. Trial registration ChiCTR2100048000. Registered 28 June 2021.