Preliminary study on gut microbiota prediction of radiation enteritis in patients with cervical and endometrial cancers / 中华放射医学与防护杂志

ABSTRACT

Objective:To explore the relationships between the gut microbiota in patients with cervical and endometrial cancers and the severity of radiation enteritis they suffered during radiotherapy.Methods:Feces samples were collected from 37 patients with cervical or endometrial cancer who received radical radiotherapy (RR) and postoperative radiotherapy (PR). Symptoms were recorded according to the grades of diarrhea and proctitis stated in CTCAE 5.0. The grade of symptoms was considered a high grade (HG) in the case of ≥ 2 and a low grade (LG). The 16S rRNA sequencing technology was used for DNA analysis of the samples.Results:The α diversity of gut microbiota was significantly higher in patients with LG symptoms (LG group) than that in patients with HG symptoms (HG group, P<0.05) and the β diversity also differed between the two groups (stress<0.2) before radiotherapy. Meanwhile, the Ruminococcus gnavus was significantly higher in the HG group than that in the LG group before radiotherapy ( P<0.05), and thus it may serve as a biomarker for the prediction of the severity of radiation enteritis in the patients before radiotherapy. The gut microbiota in the LG and HG groups showed different changes after three weeks of radiotherapy. In addition, RR patients showed higher gut microbiota diversity and less severe radiation enteritis than PR patients. Meanwhile, Faecalibacterium prausnitzii was significantly higher in RR patients than that in PR patients before radiotherapy ( P<0.05), which may correlate negatively with radiation toxicity. Conclusions:The characteristics of gut microbiota in patients with cervical and endometrial cancers were closely related to the severity of radiation enteritis they suffered during radiotherapy. Furthermore, prior treatment such as surgery might reduce radiation tolerance of the patients.