Benefits of heat-killed Lactobacillus acidophilus on growth performance, nutrient digestibility, antioxidant status, immunity, and cecal microbiota of rabbits.

Introduction: Heat-killed probiotics, as a type of inactivated beneficial microorganisms, possess an extended shelf life and broader adaptability compared to their live counterparts. This study aimed to investigate the impact of heat-killed Lactobacillus acidophilus (L. acidophilus, LA) - a deactivated probiotic on the growth performance, digestibility, antioxidant status, immunity and cecal microbiota of rabbits. Methods: Two hundred weaned Hyla rabbits were randomly allocated into five equal groups (CON, L200, L400, L600, and L800). Over a 28-day period, the rabbits were fed basal diets supplemented with 0, 200, 400, 600, and 800 mg/kg of heat-killed LA, respectively. Results: Results revealed a significant reduction in the feed-to-gain ratio (F/G) in the L600 and L800 groups (p < 0.05). Additionally, the L800 group exhibited significantly higher apparent digestibility of crude fiber (CF) and crude protein (CP) (p < 0.05). Regarding digestive enzyme activities, enhanced trypsin and fibrinase activities were observed in the L600 and L800 groups (p < 0.05). Concerning the regulation of the body's antioxidant status, the L800 group demonstrated elevated levels of superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) in both serum and ileal tissue (p < 0.05). In terms of immune capacity modulation, serum tumor necrosis factor-α (TNF-α) levels were significantly lower in the L600 and L800 groups (p < 0.05), while immunoglobulin A (IgA) and immunoglobulin M (IgM) levels were higher (p < 0.05). Additionally, the L800 group exhibited a substantial increase in secretory immunoglobulin A (SIgA) levels in the intestinal mucosa (p < 0.05). In comparison to the CON group, the L800 group exhibited a significant increase in the relative abundance of Phascolarctobacterium and Alistipes in the cecum (p < 0.05). Phascolarctobacterium demonstrated a positive correlation with SIgA (p < 0.05), IgM (p < 0.01), and Glutathione peroxidase (GSH-Px) (p < 0.05), while displaying a negative correlation with TNF-α levels (p < 0.05). Concurrently, Alistipes exhibited positive correlations with IgA (p < 0.05), IgM (p < 0.05), SIgA (p < 0.01), GSH-Px (p < 0.05), SOD (p < 0.05), and T-AOC (p < 0.01), and a negative correlation with TNF-α (p < 0.05). Discussion: In conclusion, the dietary incorporation of 600 mg/kg and 800 mg/kg of heat-killed LA positively influenced the growth performance, nutrient digestibility, antioxidant status, immune capacity and cecal microbiota of rabbits. This highlights the potential benefits of utilizing heat-killed probiotics in animal nutrition.

Perinatal risk factors for neonatal early-onset sepsis: a meta-analysis of observational studies.

OBJECTIVE: Early-onset neonatal sepsis (EONS) remains an important cause of neonatal mortality and has many risk factors, therefore, this study aimed to investigate the perinatal risk factors for EONS. METHODS: We searched CNKI, Wan Fang, VIP, CBM, PubMed, Embase, and Web of Science to compile studies regarding the incidence of neonatal early-onset sepsis, published up to 1 May 2022. To evaluate the quality of the included studies, we used the Newcastle-Ottawa Scale, and the RevMan5.3 software was used for meta-analysis. RESULTS: A total of 17 studies were included, with 1987 cases in the case group and 4814 cases in the control group. Meta-analysis showed that perinatal asphyxia or intrauterine distress (OR = 3.00, 95% CI: 2.18-4.13), amniotic fluid meconium contamination (OR = 4.51, 95% CI: 2.31-8.81), group B streptococcal (GBS) colonization in pregnant women (OR = 2.13, 95% CI: 1.48-3.05), chorioamnionitis (OR = 4.58, 95% CI: 2.61-8.05), premature rupture of membranes (OR = 2.63, 95% CI: 2.09-3.30), lower gestational age (OR = 1.31, 95% CI: 1.18-1.44), maternal urinary or reproductive tract infection (OR = 3.61, 95% CI: 2.14-6.11), perinatal fever (OR = 3.59, 95% CI: 2.25-5.71), very low birth weight (OR = 3.79, 95% CI: 2.14-6.73), and vaginal examination ≥3 times (OR = 7.95, 95% CI: 4.04-15.64) were the perinatal risk factors for EONS. CONCLUSION: Perinatal asphyxia or intrauterine distress, meconium contamination in amniotic fluid, GBS colonization in pregnant women, chorioamnionitis, premature rupture of membranes, lower gestational age, maternal urinary tract or reproductive tract infection, perinatal fever, very low birth weight, and vaginal examinations ≥3 times may increase the risk of EONS.

MiRNAs as biomarkers for diagnosis of neonatal sepsis: a systematic review and meta-analysis.

BACKGROUND: The relationship between circulating miRNAs and neonatal sepsis and the mechanism of action are still unclear at this time. Therefore, the potential diagnostic role of miRNAs in neonatal sepsis (NS) was studied through meta-analysis. METHOD: Web of Science, Cochrane Library, PubMed, and Embase are retrieved, supplemented by manual search, and the search was conducted to find related studies without time limit until May 2022.The quality of the literature was assessed via QUADAS criteria and meta-analyzed via Stata 11.0 software, including the assessment of specificity, sensitivity, likelihood ratio and diagnostic odds ratio. Then, sensitivity analysis and heterogeneity testing were conducted, and finally, the summary receiver operating characteristics (SROC) curve was drawn. RESULT: This study included 14 articles, including 20 miRNAs and 1597 newborns(control group: 727 and case group: 870). Among them, one article was of low quality, three articles were of high quality, and the rest were of medium quality. According to the results of random effects model analysis, the pooled specificity and sensitivity of miRNA for the diagnosis of NS were 0.83 (95%CI: 0.79-0.87) and 0.76 (95%CI: 0.72-0.80), respectively. And negative likelihood ratio, positive likelihood ratio, and diagnostic odds ratio were 0.29 (95%CI: 0.24-0.34), 4.51 (95%CI: 3.52-5.78), and 15.81 (95%CI: 10.71-23.35), respectively. The area under the SROC curve was 0.86, and there was no evidence publication bias detected in the funnel plot. CONCLUSION: Circulating miRNAs may be very useful in the development of early diagnostic strategies for neonatal sepsis.

The association between mannose binding lectin gene polymorphisms and the risk of neonatal sepsis: an updated meta-analysis.

Objectives: To evaluate the relationship between mannose-binding lectin (MBL) polymorphism and neonatal sepsis to provide ideas for early diagnosis and control of neonatal sepsis using meta-analysis. Methods: The China National Knowledge Infrastructure, WanFang Data, China Biological Medicine Disc, PubMed, Embase, Cochrane Library, and Web of Science databases were electronically searched to collect studies on the association between the MBL gene variants and the risk of neonatal sepsis. Original articles from case-control and cohort studies on the relationship between MBL polymorphisms and neonatal sepsis were considered eligible. Meta-analysis was performed using Stata 15.0 software. The chi-square-based Q test and I2 statistics were used to assess heterogeneity. Forest plots were used to display the results graphically. Potential publication bias was assessed using the Egger and Begg tests and funnel plots. Results: Twenty-two studies, including 4565 cases and 12,746 controls, were included in this meta-analysis. Meta-analysis showed a significant relationship between MBL rs1800450 (codon 54, G > A) and neonatal sepsis in the variant vs. wild types. However, the analysis showed MBL exon 1 gene polymorphism (A/O), MBL rs5030737 (codon 52, C > T), and rs1800451 (codon 57, G > A), involved in existing research, were not associated with the risk of sepsis in neonates. Conclusions: Current evidence shows that MBL rs1800450 is associated with neonatal culture-proven sepsis. Owing to the limited quantity and quality of the included studies, more high-quality studies are required to verify the above conclusion.

Risk factors for necrotizing enterocolitis in neonates: A meta-analysis.

Objective: The objective is to identify the risk factors for necrotizing enterocolitis (NEC) in neonates by a meta-analysis, and to provide a reference for the prevention of NEC. Methods: The databases, including Chinese Biomedical Literature Datebase, China National Knowledge Infrastructure, Wanfang database, and Weipu Periodical database, PubMed, Web of Science, Embase, Cochrane Library, were searched for studies on the risk factors for NEC in neonates. The meta-analysis was carried out with the aid of Stata software. Results: A total of 52 studies were included, with 48 case-control studies and 4 cohort studies. There were 166,580 neonates in total, with 33,522 neonates in the case group and 133,058 neonates in the control group. The meta-analysis showed that gestational diabetes (OR = 3.62, 95% CI:1.77-7.41), premature rupture of membranes (OR = 3.81, 95% CI:1.16-12.52), low birth weight (OR = 3.00, 95% CI:2.26-3.97), small for gestational age (OR = 1.85, 95% CI:1.15-2.97), septicemia (OR = 4.34, 95% CI:3.06-6.15), blood transfusion (OR = 3.08, 95% CI:2.16-4.38), congenital heart disease (OR = 2.73, 95% CI:1.10-6.78), respiratory distress syndrome (OR = 2.12, 95% CI:1.24-3.63), premature birth (OR = 5.63, 95% CI:2.91-10.92), pneumonia (OR = 4.07, 95% CI:2.84-5.82) were risk factors for NEC in neonates. Breastfeeding (OR = 0.37, 95% CI:0.23-0.59), take probiotics (OR = 0.30, 95% CI:0.22-0.40), prenatal use of glucocorticoids (OR = 0.39, 95% CI:0.30-0.50), Hyperbilirubinemia (OR = 0.28, 95% CI:0.09-0.86) were protective factors for NEC in neonates. Conclusions: Gestational diabetes, premature rupture of membranes, low birth weight, small for gestational age, septicemia, blood transfusion, congenital heart disease, respiratory distress syndrome, premature birth, and pneumonia may increase the risk of NEC in neonates. Breastfeeding, taking probiotics, prenatal use of glucocorticoids, and Hyperbilirubinemia may reduce the risk of NEC in neonates.

Silibinin Retards Colitis-associated Carcinogenesis by Repression of Cdc25C in Mouse Model.

PURPOSE: Silibinin possesses the efficacy of anticancer and anti-inflammation. We aimed to test whether silibinin could prevent colitis-associated carcinogenesis in mouse model. EXPERIMENTAL DESIGN: Azoxymethane (AOM) and dextran sulfate sodium (DSS) were used to induce colitis-associated tumorigenesis in C57BL mice. Six-to-eight-week-old male mice were gavaged with 350 or 750 mg/kg of silibinin for 10 weeks right after DSS administration. The mice were then sacrificed, and colon tissues were measured for tumor multiplicity and size. Molecular changes about proliferation, apoptosis and inflammation were tested. RESULTS: Silibinin feeding showed a dose-dependent inhibition on the size of tumor induced by AOM/DSS in mice. In addition, silibinin inhibited cell proliferation evidenced by a decrease (P < 0.05) in Ki-67 and proliferating cell nuclear antigen (PCNA). However, silibinin did not show any significant effect on inflammation, apoptosis, and the mRNA expression of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and vascular endothelial growth factor (VEGF). The experiments in vitro showed that silibinin induced cell cycle arrest at G2/M phase in CT-26 cells, a mouse colonic cancer cell line. Furthermore, silibinin reduced the expression of Cdc25C and blocked the dephosphorylation of CDK1 at multiple sites both in vitro and in vivo. CONCLUSIONS: Silibinin targets Cdc25C/CDK1 pathway and mitigates colitis-associated tumorigenesis in mice. Thus, our findings indicate the chemopreventive potential of silibinin for inflammation-associated colon cancer.

Protease-activated receptor 2 signaling modulates susceptibility of colonic epithelium to injury through stabilization of YAP in vivo.

Hippo signaling plays critical roles in intestinal regeneration. However, the mechanisms which regulate its activity in vivo are largely unknown. We hypothesize that protease-activated receptor 2 (PAR2) signaling, which could be activated by trypsin, might affect YAP activity in the setting of tissue damage and regeneration. It is found that knockout of PAR2 severely aggravates the mucosal damage induced by dextran sodium sulfate (DSS) in mouse, which correlated with notable repression of YAP protein in colonic epithelial cells. Although the cytokine expression is reduced, the damage of colonic crypt is more severe after DSS-induced colitis in PAR2-/- mouse. In vitro, PAR2 activation causes the accumulation of YAP, while knockdown of PAR2 with shRNA dramatically represses the expression of YAP protein in different intestinal epithelial cell lines. Moreover, forced expression of YAP significantly reduces the production of reactive oxygen species (ROS) and the sensitivity to nitric oxide-induced apoptosis in PAR2-deficient condition. Further studies show that PAR2 signaling stabilizes YAP protein but independent of Lats. Nevertheless PAR2 activation increased the binding of YAP with protein phosphatase PP1. Inhibition of PP1 with specific siRNA blocked PAR2-induced dephosphorylation of YAP. Taken together, PAR2 signaling might modulate susceptibility of colonic epithelium to injury through stabilization of YAP.

Correlation between lymphatic endothelial markers and lymph node status or N-staging of colorectal cancer.

BACKGROUND: The purpose of this study is to examine the expression levels of lymphatic endothelial markers in colorectal cancer and to explore the correlation between the expression levels of markers and lymph node status. METHODS: Forty-seven paired fresh tumor tissues and para-cancerous tissues were collected from colorectal cancer patients who received surgical treatment between August 2015 and March 2016 in Cancer Hospital, Chinese Academy of Medical Sciences. Real-time quantitative PCR (RTQ-PCR) was used to check the expression levels of LYVE-1, VEGFR-3, Podoplanin, and Prox-1 in tumor and para-cancerous tissues. RESULTS: The positive expression rates of LYVE-1, VEGFR-3, Podoplanin, and Prox-1 in tumor tissues were 100, 93.6, 100, and 91.4%, but 100, 100, 100, and 87.2% in para-cancerous tissues. Comparing with para-cancerous tissues, tumor tissues had significantly lower expression levels of LYVE-1 (P < 0.001) and VEGFR-3 (P = 0.013) and higher levels of Podoplanin (P = 0.016) and Prox-1 (P = 0.078). There was no correlation between lymph node status and the expression level of LYVE-1 in tumor tissues (P = 0.354) or par-cancerous tissues (P = 0.617); similar results were found for VEGFR-3 (P = 0.631, 0.738), Podoplanin (P = 0.490, 0.625), and Prox-1 (P = 0.503, 0.174). Meanwhile, there was no correlation between N-staging and the expression level of LYVE-1 in tumor tissues (P = 0.914) or para-cancerous tissues (P = 0.784); similar results were found for VEGFR-3 (P = 0.493, 0.955), Podoplanin (P = 0.199, 0.370), and Prox-1 (P = 0.780, 0.234). CONCLUSIONS: There was no correlation between expression levels of lymphatic endothelial markers and lymph node status; LYVE-1, VEGFR-3, Podoplanin, and Prox-1 could not be used for predicting the lymph node status or N-staging of colorectal cancer.

Differential expression of LEF1/TCFs family members in colonic carcinogenesis.

Lef1/Tcfs family, which includes Lef1, Tcf1, Tcf3, and Tcf4, is required for the transcriptional activation induced by ß-catenin. However, whether all the members play the same role in colon carcinogenesis is not clear. We found that Lef1 and Tcf1, but not Tcf3 and Tcf4, were upregulated at both mRNA and protein level with the formation of colon tumor in AOM-DSS mouse model. The same profiles were seen in human specimens with the evolvement from adenoma to adenocarcinoma. Additionally, Lef1 and Tcf1 were correlated with a subgroup of Wnt target genes, including Lgr5, a key gene of intestinal stem cell. Further studies supported the role of Tcf1 on sphere formation and transcriptional regulation of Lgr5 in vitro. Interestingly, 3' UTR of each Lef1/Tcfs member were targeted by diverse miRNAs, which were negatively correlated with respective member in human colon cancer specimens. Furthermore, these miRNAs were verified to repress Tcf1 and Lef1 in vitro. Taken together, Lef1 and Tcf1 showed oncogenic effect in colonic carcinogenesis. Cellular context of miRNAs might play important roles in carcinogenesis by altering the expression pattern of Lef/Tcfs members. © 2017 Wiley Periodicals, Inc.

Discovery of potential colorectal cancer serum biomarkers through quantitative proteomics on the colonic tissue interstitial fluids from the AOM-DSS mouse model.

Quantitative proteomic analysis was performed using iTRAQ to discover colorectal cancer (CRC)-related proteins in tissue interstitial fluids (TIFs). A typical inflammation-related CRC mouse model was generated using azoxymethane-dextran sodium sulfate (AOM-DSS), and TIFs were collected from these mice in four stages during CRC development. Using stringent criteria, a total of 144 proteins displayed changes in their abundances during tumor growth, including 45 that consecutively increased, 17 that consecutively decreased and 82 that changed irregularly. Of these 144 proteins, 24 of the consecutively changed proteins were measured using MRM in individual TIF samples, and 18 were verified. Twelve proteins verified to be consecutively increased in TIFs were examined using MRM to evaluate changes in their abundance in individual mouse serum samples. The abundances of leucine-rich alpha-2-glycoprotein 1 (LRG1), tubulin beta-5 chain (TUBB5) and immunoglobulin J chain (IGJ) were significantly higher in CRC mice than in control mice. Using clinical samples and MRM, we further verified that LRG1 and TUBB5 are potential CRC serum biomarkers. These data demonstrate that coupling dynamic TIF proteomics with targeted serum proteomics in an animal model is a promising avenue for pursuing the discovery of tumor serum biomarkers. BIOLOGICAL SIGNIFICANCE: Colorectal cancer (CRC) is one of the most dangerous diseases worldwide. However, few of CRC biomarkers possess satisfied specificity and sensitivity in clinical practices. Exploration of more CRC biomarkers, especially in serum, is an urgent and also a time-consuming campaign in the CRC study. Our study demonstrates that quantitatively evaluating the phase-dependent proteins in colonic tissue interstitial fluids from AOM-DSS mice is a feasible and effective way for exploration of the CRC-related proteins and the potential serum biomarkers. We identified two proteins, LRG1 and TUBB5, which may be practicable in human clinical samples as CRC serum biomarkers. To sum up, this study provides a novel angle to explore the critical factors in tumorigenesis and a new pipeline for potential serum biomarker discovery and verification.

Proteinase-activated receptor 2 promotes cancer cell migration through RNA methylation-mediated repression of miR-125b.

Proteinase activated-receptor 2 (PAR2) participates in cancer metastasis promoted by serine proteinases. The current study aimed to test the molecular mechanism by which PAR2 promotes cancer cell migration. In different cancer cells, activation of PAR2 by activating peptide (PAR2-AP) dramatically increased cell migration, whereas knock down of PAR2 inhibited cellular motility. The PAR2 activation also repressed miR-125b expression while miR-125b mimic successfully blocked PAR2-induced cell migration. Moreover, Grb associated-binding protein 2 (Gab2) was identified as a novel target gene of miR-125b and it mediated PAR2-induced cell migration. The correlation of PAR2 with miR-125b and Gab2 was further supported by the findings obtained from human colorectal carcinoma specimens. Remarkably, knock down of NOP2/Sun domain family, member 2 (NSun2), a RNA methyltransferase, blocked the reduction in miR-125b induced by PAR2. Furthermore, PAR2 activation increased the level of N(6)-methyladenosine (m(6)A)-containing pre-miR-125b in NSun2-dependent manner. Taken together, our results demonstrated that miR-125b mediates PAR2-induced cancer cell migration by targeting Gab2 and that NSun2-dependent RNA methylation contributes to the down-regulation of miR-125b by PAR2 signaling. These findings suggest a novel epigenetic mechanism by which microenvironment regulates cancer cell migration by altering miRNA expression.

Activation of mucosal mast cells promotes inflammation-related colon cancer development through recruiting and modulating inflammatory CD11b(+)Gr1(+) cells.

Mast cells (MCs) have been reported to be one of the important immunoregulatory cells in promoting the development of colitis-related colon cancer (CRC). It is not clear which MC subtypes play critical roles in CRC progression from colitis to cancer because mucosal mast cells (MMCs) are distinct from connective tissue mast cells (CTMCs) in maintaining intestinal barrier function under homeostatic and inflammatory conditions. In the current study, we found that MMC numbers and the gene expressions of MMC-specific proteases increased significantly in an induced CRC murine model. The production of mast cell protease-1 (mMCP-1) after MMC activation not only resulted in the accumulation of CD11b(+)Gr1(+) inflammatory cells in the colon tissues but also modulated the activities of CD11b(+)Gr1(+) cells to support tumor cell growth and to inhibit T cell activation. Blocking the MMC activity in mice that had developed colitis-related epithelium dysplasia, CD11b(+)Gr1(+) infiltration was reduced and CRC development was inhibited. Our results suggest that MMC activation recruited and modulated the CD11b(+)Gr1(+) cells to promote CRC and that MMCs can be potential therapeutic targets for the prevention of CRC development.

The regulation of miRNAs in inflammation-related carcinogenesis.

Chronic inflammation plays important roles in the initiation and development of various cancers, particularly gastrointestinal cancer. Cancer is characterized by stepwise accumulation of genetic and epigenetic alterations of genes. As a high risk factor for cancer, chronic inflammatory response produces great amount of mediators, including cytokines, reactive oxygen and nitrogen species, proteinases, which can induce genetic and epigenetic changes of cancer-associated genes and pathways. Furthermore, inflammation also modulates the expression of miRNAs that not only regulate the expression of tumor-related proteins but also enhance the tumor-promoting inflammatory process. In the current review, we summarize the mechanisms by which inflammatory mediators and signaling regulate the biosynthesis of miRNAs, as well as the involvement of miRNAs in the feedback loops promoting inflammation-associated carcinogenesis.

P53-dependent miRNAs mediate nitric oxide-induced apoptosis in colonic carcinogenesis.

Both miRNAs and nitric oxide (NO) play important roles in colonic inflammation and tumorigenesis. Resistance of colonic epithelial cells to apoptosis may contribute to tumor development. We hypothesized that some miRNAs could increase the resistance of colonic cancer cells to nitric oxide-induced apoptotic cell death. Here we show that NO induced apoptosis and stimulated expression of some miRNAs. Loss of p53 not only blocked NO-induced apoptosis but also dramatically inhibited the expression of NO-related miRNAs, such as miR-34, miR-203, and miR-1301. In addition, blockage of p53-dependent miRNAs significantly reduced NO-induced apoptosis. Furthermore, forced expression of these miRNAs rendered HT-29 cells, which are resistant to apoptosis with mutant p53, more sensitive to NO-induced apoptotic cell death. Most interestingly, in a colitis-associated colon cancer mouse model, the level of miRNAs dropped significantly, accompanied by downregulation of p21, which is a key target gene of p53. In human colorectal cancer samples, the expression of miR-34 significantly correlated with the level of inducible nitric oxide synthase (iNOS). We contend that increased NO production may select cells with low levels of p53-dependent miRNAs which contributes to human colonic carcinogenesis and tumor progression.

[Changes of expression of miR-155 in colitis-associated colonic carcinogenesis].

OBJECTIVE: To investigate the changes of miR-155 and its target genes in colitis-associated carcinogenesis. METHODS: Colitis-associated colon cancer was induced by azoxymethane (AOM) and dextran sulfate sodium (DSS) in C57BL/6 mice. Mice of three different stages during the development of colon cancer were obtained, named AD1, AD2 and AD3, respectively. A control group of mice without any treatment and a DSS only group representing chronic inflammation without cancer were set up as well. Colon tissue was collected and expression of miR-155 in the colon tissues was measured by real-time fluorescent quantitative PCR. TargetScan and PicTar were used to predict potential target genes of miR-155, which were then preliminarily screened with our gene expression microarray database of AOM-DSS mouse model. Regular PCR was used to confirm the changes of the expression of these potential target genes in AOM-DSS mouse model. RESULTS: Colitis-associated colon cancer was effectively induced by azoxymethane and dextran sulfate sodium in C57BL/6 mice. Histological examination revealed that the evolution process was sequentially from normal, mild dysplasia, moderate dysplasia, and severe dysplasia to adenocarcinoma in the AOM-DSS mouse model. The level of miR-155 was gradually elevated with the formation of colitis-associated colon cancer. There was no significant difference between the levels of miR-155 expression in the DSS group (0.005 6 ± 0.003 7) and control group (0.012 0 ± 0.005 1) (P > 0.05), but the level of miR-155 in the AD3 group (0.054 4 ± 0.027 0) was significantly higher than that of the DSS group (0.005 6 ± 0.003 7)(P < 0.01). No significant change of miR-155 expression was found in the DSS only group. The relative expression levels of miR-155 in the control group, DSS only group and AD3 group were 0.012 0 ± 0.005 1, 0.005 6 ± 0.003 7, 0.054 4 ± 0.027 0, respectively. Data analysis with the gene expression microarray showed that Tle4, Kcna1, Itk, Bcorl1, Cacna1c, Rspo2 and Foxo3 were potential target genes of miR-155 in the AOM-DSS mouse model. Changes of Kcna1 and Cacna1c in the AOM-DSS mouse model were validated to be consistent with the changes obtained with the gene expression microarray. CONCLUSION: The up-regulation of miR-155 is related to colitis-associated carcinogenesis, but is irrelevant to chronic inflammation in the mouse model.