VSL#3 probiotic modifies mucosal microbial composition but does not reduce colitis-associated colorectal cancer

Abstract

Although probiotics have shown success in preventing the development of experimental colitis-associated colorectal cancer (CRC), beneficial effects of interventional treatment are relatively unknown. Here we show that interventional treatment with VSL#3 probiotic alters the luminal and mucosally-adherent microbiota, but does not protect against inflammation or tumorigenesis in the azoxymethane (AOM)/Il10−/− mouse model of colitis-associated CRC. VSL#3 (109 CFU/animal/day) significantly enhanced tumor penetrance, multiplicity, histologic dysplasia scores, and adenocarcinoma invasion relative to VSL#3-untreated mice. Illumina 16S sequencing demonstrated that VSL#3 significantly decreased (16-fold) the abundance of a bacterial taxon assigned to genus Clostridium in the mucosally-adherent microbiota. Mediation analysis by linear models suggested that this taxon was a contributing factor to increased tumorigenesis in VSL#3-fed mice. We conclude that VSL#3 interventional therapy can alter microbial community composition and enhance tumorigenesis in the AOM/Il10−/− model.

Potential markers for early diagnostics of Colorectal cancer and Inflammatory bowel disease in humans : intestinal microorganisms and immune system (teammates or rivals)

“…Microbiome plays an important role in the maintenance of host homeostasis by synthesis of vitamin K, production of different nutrients, influencing mucosal immune system, defence against translocation and outgrowth of undesirable pathogenic microorganisms [12,13]. The composition of intestinal microbiome is very heterogeneous with more than 1000 different microbial species.…”

“…can significantly influence qualitative and quantitative composition of microbiome [5]. These changes, so called intestinal dysbiosis, have been considered to be promoting factor for IBD and subsequent CRC development [13]. Some bacterial strains can be the "drivers" contributing to CRC development.…”

Analysis of Changes in Diversity and Abundance of the Microbial Community in a Cystic Fibrosis Patient over a Multiyear Period

“…Illumina HiSeq 2000 technology was used to sequence the 72 samples used for this study. Raw paired-end sequences were processed as described previously (19)(20)(21). Briefly, a minimum of 70 continuous matching nucleotides across the length of the ungapped alignment were required to produce each merged sequence.…”

Modification in the diet can induce beneficial effects against breast cancer

“…The benefits of probiotics on the gut immune system in the prevention of cancer has also been previously described [73,74] . There are many different mechanisms by which probiotics and fermented products containing viable LAB may lower the risk of colon cancer; among them, the modulation of the intestinal microbiota [75][76][77][78][79][80] , the inactivation of carcinogenic compound [81][82][83] , anti-oxidant effects [84][85][86] , and the modulations of the host's immune response [87][88][89] . Recently, the administration of probiotic Dahi containing Lactobacillus (L.) acidophilus LaVK2 and Bifidobacterium bifidum BbVK3 alone or in combination of piroxicam showed anti-neoplastic and anti-proliferative activities in a model of DMH-induced CRC in rats [90] .…”