Table 1 Bacteria featured in studies evaluating the association between microbial composition and radiation toxicities.
From: Exploiting dietary fibre and the gut microbiota in pelvic radiotherapy patients
Model | Treatment | Cancer | Pre-/post-RT and main findings | Reference |
|---|---|---|---|---|
Human (N = 35) | CRT (Pelvic radiotherapy with cisplatin) | Cervical cancer | Pre-RT. Patients who later experienced a greater decline in GI function had decreased o_Clostridiales and g_Desulfovibrio, and increased g_Sutterella, g_Finegoldia and f_Peptococcaceae | [35] |
Human (RE = 10, non-RE = 8) | Pelvic RT (50.4 Gy/28) | Cervical cancer | Pre-RT. Patients who later developed RE had an increased abundance of g_Coprococcus. Post-RT. Patients with RE had a significantly increased p_Proteobacteria, c_Gammaproteobacteria, g_Serratia, g_Bacteroides and g_Prevotella_9, and decreased g_Bacteroides. | [59] |
Human (acute = 32, late = 87, RE = 9, control = 6) | Prostate and seminal vesicles and/or lymph node RT (55–74 Gy) | Prostate cancer | Pre-RT. Patients with RE had an increased abundance of g_Clostridium IV, g_Roseburia, and g_Phascolarctobacterium. | [90] |
Human (cancer = 11, control = 4) | Pelvic RT (44–50 Gy) | Cervical, anal, colorectal cancer | Pre-RT. Patients who later developed diarrhoea had an increased p_Firmicutes to p_Bacteroidetes ratio, an increased abundance of g_Bacteroides, g_Dialister and g_Veillonella and a decreased abundance of g_Clostridium XI and XVIII, g_Faecalibacterium, g_Oscillibacter, g_Parabacteroides, g_Prevotella and unclassified (genus: others). | [17] |
Human (cancer = 10, control = 5) | Pelvic RT (43–50 Gy) | Abdominal tumour | Pre-RT. Patients who later developed diarrhoea had an increased abundance of c_Bacilli and p_Actinobacteria. | [60] |
Mouse | Abdominal IR (15 Gy) | – | Post-RT. Transplantation of inulin-derived gut microbiota and metabolites mitigated IR-induced colonic fibrosis. The proportion of the SCFA-producers was significantly higher in the inulin + IR group compared to that found in the IR group. The SCFA-producers include g_Allobaculum, g_Bacteroides, g_Odoribacter, g_Alloprevotella, g_Parasutterella, g_unidentified_Lachnospiracea, g_Bifidobacterium, g_unidentified_Clostridiales, g_Blautia, g_Intestinimonas. | [135] |
Mouse | Abdominal IR (10 Gy) | – | Pre-RT. Antibiotic cocktail (metronidazole, vancomycin, ampicillin and gentamicin) mitigated radiation-induced intestinal injury by reducing inflammation and intestinal fibrosis. Alpha diversity of antibiotic cocktail group was significantly lower compared to control. | [136] |
Mouse | Total body IR (8.0 to 9.2 Gy) | – | Post-RT. Increased abundance of f_Lachnospiraceae and f_Enterococcaceae in the gut microbiome of mice surviving high dose IR (radioprotective effects). | [11] |
Mouse | Localised internal RT (22 Gy) | – | Pre-RT. GF mice colonised with irradiated microbiota manifested a more severe damage following irradiation compared to control, and they had increased abundance of p_Proteobacteria, p_Bacteroidetes, g_Parabacteroides and g_Sutterella spp., and decreased abundance of p_Firmicutes and members belonging to o_Clostridiales. | [65] |
Mouse | Total body IR (6.5 Gy) | – | Post-RT. Faecal microbiota transplantation from healthy mouse donor rescued the dramatic decrease of small intestine intact villi and thickened the gut mucosal injured by irradiation. IR reduced g_Bacteroides (or g_Lactobacillus) and this was restored by faecal microbiota transplantation. | [130] |
