The effect of probiotic and synbiotic consumption on the most prevalent chemotherapy-related complications: A systematic review of current literature

Targeting the gut microbiome to control drug pharmacomicrobiomics: the next frontier in oral drug delivery

INTRODUCTION

The trillions of microorganisms that comprise the gut microbiome form dynamic bidirectional interactions with orally administered drugs and host health. These relationships can alter all aspects of drug pharmacokinetics and pharmacodynamics (PK/PD); thus, there is a desire to control these interactions to maximize therapeutic efficacy. Attempts to modulate drug-gut microbiome interactions have spurred advancements within the field of 'pharmacomicrobiomics' and are poised to become the next frontier of oral drug delivery.

AREAS COVERED

This review details the bidirectional interactions that exist between oral drugs and the gut microbiome, with clinically relevant case examples outlining a clear motive for controlling pharmacomicrobiomic interactions. Specific focus is attributed to novel and advanced strategies that have demonstrated success in mediating drug-gut microbiome interactions.

EXPERT OPINION

Co-administration of gut-active supplements (e.g. pro- and pre-biotics), innovative drug delivery vehicles, and strategic polypharmacy serve as the most promising and clinically viable approaches for controlling pharmacomicrobiomic interactions. Targeting the gut microbiome through these strategies presents new opportunities for improving therapeutic efficacy by precisely mediating PK/PD, while mitigating metabolic disturbances caused by drug-induced gut dysbiosis. However, successfully translating preclinical potential into clinical outcomes relies on overcoming key challenges related to interindividual variability in microbiome composition and study design parameters.

Gut microbiota associated with the mitigation effect of synbiotics on adverse events of neoadjuvant chemotherapy in patients with esophageal cancer: A retrospective exploratory study

Introduction. Our synbiotics (Lacticaseibacillus paracasei strain Shirota, Bifidobacterium breve strain Yakult, and galacto-oligosaccharides: LBG) helps mitigate serious adverse events such as febrile neutropenia (FN) and diarrhoea in oesophageal cancer patients receiving neoadjuvant chemotherapy (NAC). Unfortunately, LBG therapy does not benefit all patients.Hypothesis/Gap Statement. Identification of the gut microbiota species involved in adverse events during chemotherapy could help predict the onset of adverse events. Identification of the gut microbiota that influence the efficacy of LBG could also help establish a diagnostic method to identify patients who will respond to LBG before the initiation of therapy.Aim. To identify the gut microbiota involved in adverse events during NAC and that affect the efficacy of LBG therapy.Methodology. This study was ancillary to a parent randomized controlled trial in which 81 oesophageal cancer patients were recruited and administered either prophylactic antibiotics or LBG combined with enteral nutrition (LBG+EN). The study included 73 of 81 patients from whom faecal samples were collected both before and after NAC. The gut microbiota was analysed using 16S rRNA gene amplicon sequencing and compared based on the degree of NAC-associated adverse events. Furthermore, the association between the counts of identified bacteria and adverse events and the mitigation effect of LBG+EN was also analysed.Results. The abundance of Anaerostipes hadrus and Bifidobacterium pseudocatenulatum in patients with no FN or only mild diarrhoea was significantly higher (P<0.05) compared to those with FN or severe diarrhoea. Moreover, subgroup analyses of patients receiving LBG+EN showed that the faecal A. hadrus count before NAC was significantly associated with a risk of developing FN (OR, 0.11; 95 % CI, 0.01-0.60, P=0.019). The faecal A. hadrus count after NAC was positively correlated with intestinal concentrations of acetic acid (P=0.0007) and butyric acid (P=0.00005).Conclusion. Anaerostipes hadrus and B. pseudocatenulatum may be involved in the ameliorating adverse events and can thus be used to identify beforehand patients that would benefit from LBG+EN during NAC. These results also suggest that LBG+EN would be useful in the development of measures to prevent adverse events during NAC.

Probiotics enhances anti-tumor immune response induced by gemcitabine plus cisplatin chemotherapy for urothelial cancer

Chemotherapy drugs, such as gemcitabine and cisplatin (GC), are frequently administered to patients with advanced urothelial carcinoma, however the influence of the gut microbiota on their action is unclear. Thus, we investigated the effects of GC on the gut microbiome and determined whether oral supplementation with a probiotics mixture of Lactobacillus casei Shirota and Bifidobacterium breve enhanced the anti-tumor immune response. After subcutaneous inoculation with MBT2 murine bladder cancer cells, syngenic C3H mice were randomly allocated into eight groups. The gut microbiome cluster pattern was altered in both the GC and oral probiotics groups (p = 0.025). Both tumor-bearing conditions (no treatment) and GC chemotherapy influenced Pseudoclostridium, Robinsoniella, Merdimonas, and Phocea in the gut. Furthermore, comparison of the GC-treated and GC + probiotics groups revealed an association of four methyltransferase family enzymes and two short-change fatty acid-related enzymes with oral probiotics use. A significant difference in tumor volume was observed between the GC and GC + probiotics groups at week 2 of treatment. Additionally, decreased recruitment of cancer-associated fibroblasts and regulatory T cells, and activation of CD8⁺ T cells and dendritic cells were observed in the tumor microenvironment. Our findings reveal the positive effects of a probiotics mixture of Lactobacillus and Bifidobacterium in enhancing anti-tumor effects through the gut-tumor immune response axis. Future clinical trials are needed to evaluate the full benefits of this novel supplement with oral probiotics in patients with advanced urothelial carcinoma.

Nonpharmacological approaches for improving gut resilience to chemotherapy

PURPOSE OF REVIEW

Mucositis of the gastrointestinal tract is a debilitating side effect of chemotherapy that negatively influences treatment tolerance and patient life quality. This review will evaluate the recent literature on nonpharmacological strategies that have the potential to improve chemotherapy-induced mucositis (CIM).

RECENT FINDINGS

Alternatives to pharmacological approaches have shown great promise in preventing CIM. Natural products, including curcumin, ginseng, quercetin, and patchouli all show potential in mitigating CIM. In addition, dietary patterns, such as the elemental diet, high fiber diet, and diets high in amino acids have documented benefits in preventing CIM. Perhaps the greatest advancement coming to this arena in recent years is in the field of probiotics. Indeed, research on single species as well as probiotic mixtures show potential in reducing CIM insofar as probiotics are now being suggested for treatment of CIM by governing bodies. Although behavioral interventions including psychological interventions and exercise interventions have shown promise in reducing cancer therapy-related side effects, more work in this domain is warranted and particularly in the context of CIM.

SUMMARY

Alternatives to pharmacological approaches show great potential for use in prevention and treatment of CIM and should be further developed for use in the clinic.