The animal's microbiome and cancer: A translational perspective

Abstract

Cancer is a substantial global health problem both in humans and animals with a consistent increase in mortality and incidence rate. The commensal microbiota has been involved in the regulation of several physiological and pathological processes, both within the gastrointestinal system and at distant tissue locations. Cancer is not an exception, and different aspects of the microbiome have been described to have anti‐ or pro‐tumour effects. Using new techniques, for example high‐throughput DNA sequencing, microbial populations of the human body have been largely described and, in the last years, studies more focused on companions' animals have emerged. In general, the recent investigations of faecal microbial phylogeny and functional capacity of the canine and feline gut have shown similarities with human gut. In this translational study we will review and summarize the relation between the microbiota and cancer, in humans and companion animals, and compare their resemblance in the type of neoplasms already studied in veterinary medicine: multicentric and intestinal lymphoma, colorectal tumours, nasal neoplasia and mast cell tumours. In the context of One Health, microbiota and microbiome integrative studies may contribute to the understanding of the tumourigenesis process, besides offering an opportunity to develop new diagnostics and therapeutic biomarkers both for veterinary and human oncology.

The Importance of Intestinal Microbiota and Dysbiosis in the Context of the Development of Intestinal Lymphoma in Dogs and Cats

“…Due to the considerable diversity of the bacterial biota and its intricate interactions with the intestinal epithelium, the examination of the biological community of intestines poses challenges [ 26 ]. Recent studies have demonstrated that the microbiotic environment of the gut and its functions in dogs and cats are similar to those in humans [ 30 ]. Short-chain fatty acids (SCFAs) produced by these microbes are indispensable for energizing the colon lining cells and supporting microbial metabolic functions.…”

Cancerogenic parasites in veterinary medicine: a narrative literature review

“…The parasite-cancer relationship, both putative and confirmed, was observed in a range of domestic (dog, cats, ruminants, rats, mice, and poultry species) and wild or exotic species (prosimians, New-World and Old-World monkeys, snakes, and muskrats). A total of 15 parasite genera were identified, with the majority (14) being metazoan, especially (but not exclusively) helminths. The parasitic species identified were trematodes (C. sinensis, Fasciola spp., O. viverrini, Platynosomum illiciens, S. mansoni), cestodes (T. taeniformis), nematodes (G. pulchrum, S. lupi, Heterakis spp., Nochtia nochti, Ollulanus trichuspis, Ophidascaris sp., Trichinella spp.…”

“…The oncologic burden is increasing in veterinary medicine as well [12], and the list of pathogens responsible for animal cancer development continues to grow [13,14]. In addition to various viral [15], putative bacterial species [16], and transmissible tumor cells [17][18][19] that cause cancer, certain parasites have also been identified over the years, although an overlooking of their impact on animal health was suggested [20][21][22][23][24].…”