Probiotics and postbiotics in colorectal cancer: Prevention and complementary therapy

Table 1 Overview of the most relevant bacteria related to colorectal cancer

Enriched bacteria	Depleted bacteria	Ref.
Fusobacterium nucleatum, Peptostreptococcus spp., Porphyromonas asaccharolytica, Prevotella spp., Parvimonas micra, Bacteroides fragilis, Streptococcus gallolyticus, Escherichia coli, Campylobacter spp., Shigella spp., Enterococcus faecalis	Blautia spp., Faecalibacterium prausnitzii, Clostridium butyricum, Streptococcus thermophilus, Roseburia spp.	[4,55-57]

Table 2 Efficiency of probiotics in colorectal cancer prevention and therapy-clinical trials

Probiotic strain/synbiotics	Dose/length of the study	Trial type/sample size	Microbial changes/key outcomes	Ref.
Lactobacillus rhamnosus GG, Bifidobacterium lactis Bb12 + inulin enriched with oligofructose	1010 CFU and 10 g of prebiotic, 12 wk	Human prevention study-CRC patients (n = 15 placebo, n = 19 synbiotics), polypectomized patients (n =19 placebo, n = 21 synbiotics)	↑Bifidobacterium, ↑Lactobacillus, ↓Clostridium perfringens; ↓proliferation rate of colorectal cells and stimulation of peripheral blood mononuclear cells (↑IFNg, ↓IL-2)	Rafter et al[58]
Bifidobacterium longum BB536, Lactobacillus johnsonii La1	2 × 107 CFU or 2 × 109 CFU, 3 d preoperatively and 3 d postoperatively	CRC patients undergoing elective colorectal resection- Randomized double blind, placebo-controlled study (n = 10 placebo, n = 21 probiotics)	B. longum BB536 did not adhere to colonic mucosa only La1, ↓Enterobacteriaceae ↓Enterococcus, modulation of local immunity (↑CD3+, CD4+, CD8+, activity of dendritic cells); no clinical effect	Gianotti et al[59]
Bifidobacterium longum, Lactobacillus acidophilus, Enterococcus faecalis	3 × 108 CFU, 3 d (from -5 to -3 d) preoperatively	Single-center prospective randomized control study (n = 30 placebo, n = 30 probiotics)	↑Bifidobacterium and ↓Escherichia; ↓endotoxins, D-lactic acid, serum IL-6 and C-reactive protein; ↑serum IgG and IgA; ↓postoperative occurrence of infectious complications of CRC	Zhang et al[60]
Bifidobacterium longum, Lactobacillus acidophilus and Enterococcus faecalis	1:1:1 daily 6 × 107 CFU, 5 d	Perioperative intake of probiotics in CRC patients (n = 11 placebo, n = 11 probiotics)	↑richness and diversity of mucosal microbes, ↓Peptostreptococcus, ↓Comamonas, ↓Fusobacterium, ↑Enterococcus, ↑Proteobacteria; no clinical effect	Gao et al[61]
LactoLevure (Lactobacillus acidophilus LA-5, Lacobacillus plantarum, Bifidobacterium lactis BB-12, Saccharomyces boulardii)	1.75 × 109 CFU, 0.5 × 109 CFU, 1.75 × 109 CFU, 1.5 × 109 CFU, respectively, 1 d preoperatively and 15 d postoperatively	CRC patients undergoing surgery- Randomized, double-blind, placebo-controlled study (n = 80 placebo, n = 84 probiotics)	Reduction of the postoperative pneumonia rate, anastomotic leakage and surgical site infections; ↑gene expression of SOCS3; ↑circulating IL-6, TNF-α	Kotzampassi et al[62] (NCT02313519)
Colon DophilusTM [Bifidobacterium breve HA-129 (25%), Bifidobacterium bifidum HA-132 HA (20%), Bifidobacterium longum HA-135 (14.5%), Lactobacillus rhamnosus HA-111 (8%), Lactobacillus acidophilus HA-122 (8%), Lactobacillus casei HA-108 (8%), Lactobacillus plantarum HA-119 (8%), Streptococcus thermopilus HA-110 (6%), Lactobacillus brevis HA-112 (2%), Bifidobacterium infantis HA-116 (0.5%)]	10 × 109CFU/ daily, 12 wk	Patients with CRC, concomitantly with irinotecan chemotherapy- Randomized, placebo-controlled study (n = 23 placebo, n = 23 probiotics)	Reduction in the incidence and severity of chemotherapy induced diarrhea and incidence of enterocolitis.	Mego et al[63] (NCT01410955)
Saccharomyces boulardii	7 d preoperatively	Randomized study (n = 18 conventional treatment, n = 15 probiotics)	↓mucosal IL-1β, IL-10, and IL-23A mRNA levels; no statistical impact on postoperative infection rates	Consoli et al[64]
ProBion Clinica (Bifidobacterium lactis Bl-04 and Lactobacillus acidophilus NCFM + inulin)	1.4 × 1010 CFU, 7 × 109 CFU and 0.63 g of prebiotic, 8-78 d	Prospective randomized intervention (n = 7 placebo, n = 8 probiotics)	Increased abundance of butyrate producing bacteria ↑Firmicutes, ↑Faecalibacterium, ↑Eubacterium, ↑Roseburia ↑Lachnospira; ↓CRC associated bacteria- Fusobacterium and Peptostreptococcus	Hibberd et al[65](NCT03072641)
Simbio-flora (Lactobacillus acidophilus NCFM, Lactobacillus rhamnosus HN001, Lactobacillus casei LPC-37, Bifidobacterium lactis HN019 and fructooligosaccharide)	109 CFU and 6 g of prebiotic, 7 d preoperatively	Patients with CRC subjected to colorectal resection- Prospective, randomized, double-blind, placebo-controlled study (n = 37 placebo, n = 36 synbiotic)	Reduced inflammatory state (C-reactive protein, IL-6), reductions in morbidity, hospital length of stay, and use of antibiotics. Stimulated bowel function, decreased complications and reduced cumulative duration of antibiotic usage	Polakowski et al[66]
Lactobacillus acidophilus BCMC® 12,130, Lactobacillus lactis BCMC® 12,451, Lactobacillus casei subsp BCMC® 12,313, Bifidobacterium longum BCMC® 02120, Bifidobacterium bifidum BCMC® 02290 and Bifidobacterium infantis BCMC® 02129	30 billion CFU, twice daily for 6 mo	Randomized double-blind placebo-controlled trial (n = 25 placebo, n = 27 probiotics)	Reduction in the levels of pro-inflammatory cytokines, TNF-α, IL-6, IL-10, IL-12, IL-17A, IL-17C and IL-22.	Zaharuddin et al[32] (NCT03782428)

CRC: Colorectal cancer; IFNg: Interferon-gamma; Ig: Immunoglobulin; IL: Interleukin; TNF-α: Tumor necrosis factor-alpha.

Table 3 Efficiency of next-generation probiotics in colorectal cancer in vivo

NGP strain	Application	Study/ cohort	Mechanism/effect(s)	Ref.
Akkermansia muciniphila MucT ATCC BAA-835	pasteurized culture 1.5 × 108 CFU/100 μL or recombinant Amuc_1100 3 μg (specific outer membrane protein)/2 wk before AOM injection until sacrifice	23-wk in vivo animal study, acute colitis was induced by AOM (10 mg/kg) (intraperitoneally) + 2% DSS (in water)-male C57BL/6J mice	Prevention of AOM/DSS-induced tumorigenesis by DNA damage attenuation, cell apoptosis and abnormal proliferation. Significant amelioration of acute colitis, relieved colon shortening and splenomegaly, delayed tumor formation and reduced expression of γH2AX, cleaved caspase 3 and Ki67. Blunted CAC through the expansion and activation of cytotoxic T lymphocytes, indicated by TNF-α induction and PD-1 downregulation	Wang et al[67]
Akkermansia muciniphila ATCC BAA-835	1 × 108 CFU/mouse every other day (day 7-12), gavage administration	4-wk in vivo animal study, CRC induced by mice colon cancer cells CT-26 (1 × 106) (subcutaneously)-n = 70, male BALB/c mice	A. muciniphila colonization significantly increased inhibition rate/anti-cancer effect of FOLFOX (from 48% to 76%) and significantly decreased marker of proliferation-Ki67 (% of positively stained cells)	Hou et al[68]
Clostridium butyricum (powder by Kexing Biopharm CO., LTD)	2 × 108 CFU/0.2 mL/3 times per week, gavage administration	78 d in vivo animal study, CAC induced by intraperitoneal AOM (12.5 mg/kg) + 2.5% DSS (in water)-n = 30, C57BL/6 mice	Inhibition of NF-κB pathway and apoptosis promotion. Change in the microbiome composition-reduction of Firmicutes to Bacteroidetes ratio. Reduction of incidence and size of CRC and increase of tumor cells apoptosis. Reduction in cytokines including TNF-α, IL-6 and level of COX-2. Decrease in phosphorylation of NF-κB and level of Bcl-2. Increase in Bax expression	Liu et al[69]
Clostridium butyricum ATCC 19398 or Bacillus subtilis ATCC 23857	2.5 × 108 CFU/0.3 mL/3 times per week for 28 wk, oral administration	28 wk in vivo animal study. CRC induced with DMH (20 mg/kg body weight)/weekly (intraperitoneally)-n = 72, male C57BL/6 mice	Inhibition of intestinal tumorigenesis and modulation of immunity and inflammation. Reduction in tumor size and incidence. After supplementation with probiotics, mice showed decreased Th2 and Th17 expression and increased CD4/CD8 expression compared to DMH-treated mice. Reduced gene expression of TLR4–MYD88–NF-κB, IL-22 and increase of P21waf1 and Tlr3 mRNA levels in intestinal mucosa	Chen et al[31]

AOM: Azoxymethane; CAC: Colitis-associated cancer; CRC: Colorectal cancer; DMH: 1,2-dimethylhydrazine; DSS: Dextran sulfate sodium; FOLFOX: Oxaliplatin, fluorouracil and calcium folinate; IL: Interleukin; NF-κB: Nuclear factor-kappa B; TNF-α: Tumor necrosis factor-alpha.

Table 4 Efficiency of postbiotics on cancer cells in vitro

Probiotic strain	Derived postbiotic	Cell line	Mechanism/effect(s)	Ref.
Lactobacilus casei ATCC334	CFS (ferrichrome)	Caco-2/bbe, SKCO-1, SW620	In CFS, ferrichrome subsequently identified as the responsible molecule that induced apoptosis via JNK-DDTI3 signaling axis, thus having tumor-suppressive effect and exerted minimal effect on normal intestinal epithelial cells	Konishi et al[70]
Lactobacillus rhamnosus MD 14 MH 656799	CFS (acetate, butyrate, propionate, acetamide, thiocyanic acid, and oxalic acid)	Caco-2, HT-29	CFS with metabolites exhibited both anti-genotoxic and cytotoxic potential against CRC cells	Sharma et al[71]
Bifidobacterium adolescentis SPM0212	CFS	Caco-2, HT-29, SW480	CFS significantly inhibited the proliferation of cancer cells	Kim et al[39]
Lactobacillus fermentum KCTC 3112	CFS	CCD18-Co, HCT-116, HT-29	Induction of cancer cells apoptosis by CFS up-regulating Caspase-3, Bax, Bak, Noxa, and Bid mRNA expressions	Lee et al[38]
Lactobacillus casei (ATCC 334), Lactobacillus rhamnosus (GG ATCC 53103)	CFS	HCT-116	Anti-metastatic effects of high molecular weight fractions	Escamilla et al[40]
Lactobacillus acidophilus ATCC 4356, Lactococcus lactis ATCC 11454, Lactobacillus casei ATCC 334, Lactobacillus reuteri ATCC 55148, Saccharomyces boulardii ATCC MYA-796	CFS	HT-29	Downregulation of the expression of PGE-2 and IL-8 in cancer cells by metabolites of probiotics. CFS differently modulated IL-1β, IL-6, TNF-α, and IL-10 production by human macrophages, suggesting a peculiar anti-inflammatory activity	De Marco et al[48]
Lactobacillus casei ATCC 393	Sonicated-cell suspension	CT26, HT-29	Inhibition of cancer cells proliferation and induction of apoptosis	Tiptiri-Kourpeti et al[72]
Lactobacillus reuteri PTCC 1655	Sonicated-cell suspension	HT-29-ShE	Anti-metastatic and anti-proliferative effects	Maghsood et al[73]
Lactococcus lactis PTCC 1336	Nisin, cell wall, cytoplasmic extract of nisin	SW480	Anti-proliferative effects, associated with the decreased expression of cyclin D1 in SW480 cell line	Hosseini et al[74]
Pediococcus pentosaceus FP3, Lactobacillus salivarius FP25/FP35, Enterococcus faecium FP51	SCFAs (butyrate and propionate)	Caco-2	Significant proliferation inhibition of Caco-2 cells and activation of apoptosis	Thirabunyanon and Hongwittayakorn[75]
Streptomyces levis ABRIINW111	Extracted metabolites	SW480	SW480 growth inhibition, increased Caspase-3 and reduced Ki67 expression in a concentration/time-dependent manner; subG1 phase (apoptosis) increased by metabolites and cell cycle arrest in G1, G2/M and S phase; p53 gene expression followed SW480 cells treatment significantly	Faramarzian Azimi Maragheh et al[76]
Streptomyces sp. MUM256	MUM256 extract	HT-29, Caco-2	Antioxidant properties, cytotoxicity against CRC cells by reduction in viability and induction of apoptosis (depolarization of mitochondrial membrane potential and arrest in subG1 phase)	Tan et al[77]
Clostridium butyricum ATCC 19398	SCFAs	HCT-116, HCT-8, Caco-2	Suppression of the Wnt/b-catenin signaling pathway and modulation of the gut microbiota composition.	Chen et al[25]

CFS: Cell-free supernatant; CRC: Colorectal cancer; IL: Interleukin; SCFAs: Short-chain fatty acids; TNF-α: Tumor necrosis factor-alpha.