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Global Translational Medicine Gut microbiota in Onco-Hematology

absolutely essential and achievable. In a similar fashion, metabolism, suggesting that chemotherapy incited a
pre-clinical models indicate a dual role performed by the severe compositional and functional imbalance in the
gut microbiota in response to Eloxatin (oxaliplatin); this gut microbiota that is accompanied by gastrointestinal
dual contribution was both to mechanical hyperalgesia mucositis . Based on this premise, further studies
[48]
and tumor cytotoxicity, regarded as a complication involving dysbacteriosis (dysbiosis) of gut microbiota due
commonly associated with chemotherapy by means of to chemotherapy are undeniably warranted, especially those
elevating pro-inflammatory cytokines and reactive oxygen that employ the idea of overcoming chemotherapy-related
species in the dorsal root ganglion . In pre-clinical unpleasantness. It would then be reasonable to mention
[44]
study models, radiation has been found to be a culprit that the quality of life in cancer patients could improve,
in the alteration of the gut microbiota composition. It eliminating serious adverse effects, which sometimes result
has been recognized to decrease considerable amounts in some frail patients becoming non-compliant with some
of Firmicutes while increasing Proteobacteria; this, cancer therapies by evading undesirable side effects.
therefore, increases the vulnerability to colitis attributable
to radiation. A demonstration has been performed to 3.2. Lymphoma
portray fecal microbiota transplantation (FMT) as one of A number of studies mention that the presence of specific
the useful therapeutic modalities to alleviate severe colitis microorganisms is associated with various lymphoma
that may be due to immunotherapy, also found to be presentations or manifestations. Such compelling
associated with a refractory presentation as a consequence evidence indicates a role carried out by a number of
of immunosuppressing therapies, such as both biologic organisms of pathogenic nature implicated in the growth
agents and corticosteroids, which include anti-integrin and and development of lymphoma (lymphoma-genesis);
anti-tumor necrosis factor alpha therapies. The endoscopic such organisms include the involvement of H. pylori,
resolution of colitis was in correspondence to a tenacious hepatitis C virus (HCV), and EBV. H. pylori has been
change in the gut microbiota, found to resemble that of linked to mucosa-associated lymphoid tissue lymphoma
the donor, and reorganization in the colonic inflammatory (MALToma). MALToma has been indicated in up to 70%
infiltrate to a more anti-inflammatory phenotype . These of patients treated with antibiotics to eliminate H. pylori
[45]
types of activities warrant further studies to ensure they are infection, demonstrating a link to the disease persistence
used routinely in the future. frequently associated with this particular gastric
microbiota resident. This has resulted in the regression
3.1. Chemotherapy-provoked gut microbiota of MALToma . While in cases involving marginal zone
[50]
dysbacteriosis (dysbiosis) lymphoma, HCV has been postulated to induce the initial
Chemotherapy treatment has been found to present with antigenic stimulus for B cell clonal expansion as part of the
adverse effects on the gut microbiota in both the adult and multistage progression toward the direction of lymphoma
pediatric cancer cohorts. Huang et al. performed a study growth and development of lymphoma (lymphoma-
[46]
on changes in the gut microbiota amongst 36 children genesis) . Virulence factors associated with H. pylori,
[51]
diagnosed with acute lymphoblastic leukemia (ALL) especially in MALToma, may present a possibility of being
before and after receiving a high dose of chemotherapy biomarkers since the presence of H. Pylori presents an idea
(methotrexate). They established that the total gut microbial or predict an outcome in H. pylori-positive MALToma.
content in fecal samples diminished by 29.6% compared Since studies involving gut microbiota demonstrate the
to healthy individuals (controls), whereby they identified potential of presenting biomarkers, they may, in future
substantial reductions in Bifidobacteria, Lactobacillus, studies, present a potential of being used as non-invasive
and E. coli . In addition, Montassier et al. examined investigations, even though a number of avenues still need
[46]
[47]
pre- and post-chemotherapy fecal samples of 28 adult to be explored to reach such a level.
patients diagnosed with non-Hodgkin’s lymphoma to
assess the functional mechanisms of the gut microbiota 3.2.1. Preclinical studies investigating links between
toward mediating the pathophysiology of mucositis. gut microbiota and lymphoma
A condition called mucositis is characterized by painful Animal models for cancer studies have proven to be quite
inflammation and ulceration of the mucous membranes helpful in demonstrating a link between carcinogenesis
lining the digestive tract, typically present in about 70% and gut microbiota (Figure 1). Cancer is typically thought
of patients following chemotherapy [48,49] . A significant to develop in a multi-step process starting with initiation,
decrease in Actinobacteria and Firmicutes and an increase promotion, and finally, progression. As the disease
in the abundance of Proteobacteria was detected alongside progression continues, cells tend to form the so-called
a reduced capability for nucleotide, vitamin, and energy “hallmarks of cancer” which comprises of a sustained form

Volume 2 Issue 2 (2023) 4 https://doi.org/10.36922/gtm.0389