A Study Of The Impact Of XELOX And GP Chemotherapy On Intestinal Microbiota And The Interventional Effect Of Probiotic Bacilli Lichun

Background & Aim:Recent studies have shown that the alteration of intestinal microbiota may be closely related to the change of intestinal function and mucositis during chemotherapy. Chemotherapy leads to several side effects, with gastrointestinal (GI) mucositis being one of the most frequent. Current models of GI mucositis pathophysiology are generally silent on the role of the intestinal microbiome.The aim of the current study is to identify the role of probiotics during chemotherapy investigating its protective effect on the intestinal microbiota.Method:Patients diagnosed with gastric cancer and pulmonary cancer who received adjuvant chemotherapy were enrolled. We amplified and sequenced 16S rDNA genes from faecal samples before and after chemotherapy in 20 patients with gastric cancer and non-small cell lung cancer who received the same chemotherapy regimen and no other concomitant therapy such as antibiotics. Sequencing was done using Illumina Hiseq which targets 16S-rDNA variable region V4 and V5 of bacterium. Abundance and diversity of gut microbiota in each sample was determined. Data in each group were presented as Mean+SD, Student-t test and ANOVA followed by Post-hoc Tukey test were used for the statistical analysis. Mann-Whitney U test and Post-hoc Conover-Inman were also used to test the statistical significance between groups. A P value<0.05 was considered as statistically significant.Results:From Sep 2013 to March 2015, a total of 20 gastric cancer patients and 20 lung cancer persons enrolled. Patients were then randomized to two groups, one received probiotics while the other served as control group. There were no significant differences in baseline characteristics between two groups. Probitics could significantly reduce the incidence of chemotherapy-induced diarrhea,nausea, vomiting and abdominal pain. We also found that probitics accelarate the recovery process of intestinal microbiota during chemotherapy.In addition,compared with control group, patients in probiotic group had significantly higher abundance in Prausnitzii,Faecalibacterium,Ruminococcus and bromii,and significantly lower abundance in Klebsiella, Escherichia coli,Enterobacteriaceae,Proteobacteria and Gammaproteobacteria.Conclusion:1. Probitics could significantly reduce the incidence of chemotherapy-induced diarrhea.2. Probitics accelarate the recovery process of intestinal microbiota diversity during chemotherapy.3.At the initial phase of chemotherapy, probiotics could significantly alter the composition of intestinal microbes.