Corticosteroid therapy in ulcerative colitis: Clinical response and predictors.

AIM: To evaluate clinical response to initial corticosteroid (CS) treatment in Chinese ulcerative colitis patients (UC) and identify predictors of clinical response. METHODS: Four hundred and twenty-three UC patients who were initially treated with oral or intravenous CS from 2007 to 2011 were retrospectively reviewed at eight inflammatory bowel disease centers in China, and 101 consecutive cases with one-year follow-up were analyzed further for clinical response and predictors. Short-term outcomes within one month were classified as primary response and primary non-response. Long-term outcomes within one year were classified as prolonged CS response, CS dependence and secondary non-response. CS refractoriness included primary and secondary non-response. Multivariate analyses were performed to identify predictors associated with clinical response. RESULTS: Within one month, 95.0% and 5.0% of the cases were classified into primary response and non-response, respectively. Within one year, 41.6% of cases were assessed as prolonged CS response, while 49.5% as CS dependence and 4.0% as secondary non-response. The rate of CS refractoriness was 8.9%, while the cumulative rate of surgery was 6.9% within one year. After multivariate analysis of all the variables, tenesmus was found to be a negative predictor of CS dependence (OR = 0.336; 95%CI: 0.147-0.768; P = 0.013) and weight loss as a predictor of CS refractoriness (OR = 5.662; 95%CI: 1.111-28.857; P = 0.040). After one-month treatment, sustained high Sutherland score (≥ 6) also predicted CS dependence (OR = 2.347; 95%CI: 0.935-5.890; P = 0.014). CONCLUSION: Tenesmus was a negative predictor of CS dependence, while weight loss and sustained high Sutherland score were strongly associated with poor CS response.

MicroRNA-185 suppresses growth and invasion of colon cancer cells through inhibition of the hypoxia­inducible factor-2α pathway in vitro and in vivo.

MicroRNAs (miRs) are small non­coding RNAs with regulatory roles, which are involved in a broad spectrum of physiological and pathological processes, including cancer development and progression. However, the function of miR­185 in the development of human colon cancer has not yet been investigated. In this study, the association between miR­185 expression and the clinicopathological characteristics of patients with colon cancer was analyzed using quantitative polymerase chain reaction (qPCR). Using a gain­of­function approach, the effects of miR­185 overexpression on the expression of hypoxia­inducible factor­2α (HIF­2α), proliferating cell nuclear antigen (PCNA) and matrix metallopeptidase­2 (MMP­2) were investigated in SW620 colon cancer cells using qPCR and western blotting. Functional analysis of cellular proliferative activities, by MTT assay, and invasive potential, by Transwell assay, was conducted on SW620 cells expressing low levels of miR­185. miR­185 was found to be significantly downregulated in cancer tissues compared with adjacent non­cancerous tissues, and was negatively correlated with lymph node metastasis of colon cancer (P<0.001). miR­185 overexpression in vitro impeded cellular proliferation and invasive potential with reduced expression of HIF­2α, PCNA and MMP­2 in SW620 cells transfected with an miR­185 mimic. In addition, the tumor volumes in SW620 subcutaneous nude mouse models treated with miR­185 were significantly smaller than those of the control group. In conclusion, these findings indicate that miR­185 as a tumor suppressor may affect the development of colon cancer cells via inhibition of HIF­2α signaling, suggesting that miR­185 may serve as a potential therapeutic target in cancer treatment.

Recovery from TNBS-induced colitis leads to the resistance to recurrent colitis and an increased ratio of FOXP3 to CD3 mRNA.

OBJECTIVE: The aim of our study was to investigate the effects of the recovery from acute colitis on recurrent colitis with 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice. METHODS: Acute colitis was induced via an intrarectal injection of TNBS. For recurrent colitis, mice were intrarectally treated with a repeated TNBS 14 days after the first TNBS administration. And another two groups (control and recovery groups) were added to the analysis. Disease activity index (DAI), macroscopic and histological assessments, mRNA expression of interleukin (IL)-1ß, IL-6, tumor necrosis factor (TNF), IL-10, forkhead box P3 (FOXP3) and the ratio of FOXP3 to CD3 in the colonic tissues were evaluated. RESULTS: Mice developed colitis after treated with TNBS. After the last TNBS administration, DAI in the recurrent colitis group was lower than that in the acute colitis group. In the recurrent colitis group, the mice exhibited longer colon length, reduced histological damage and lower IL-1ß, IL-6, TNF, IL-10 mRNA expression in the colon compared with the acute colitis group. The ratio of FOXP3 to CD3 mRNA expression in the colon of recurrent colitis was higher than that in the acute colitis. There was a significant negative correlation between the ratio of FOXP3 to CD3 mRNA expression and DAI in the acute and recurrent colitis groups (r= -0.808, P<0.05). CONCLUSIONS: Mice that recovered from TNBS-induced acute colitis with intestinal epithelial disruption are resistant to recurrent colitis, which is associated with an increased ratio of FOXP3 to CD3 mRNA expression.

BMP2 induces PANC-1 cell invasion by MMP-2 overexpression through ROS and ERK.

The emerging roles of bone morphogenetic proteins (BMPs) in the initiation and progression of multiple cancers have drawn great attention in cancer research. We hypothesized that BMP2 promotes cancer metastasis by modulating MMP-2 secretion and activity through intracellular ROS regulation and ERK activation in human pancreatic cancer. Our data show that stimulation of PANC-1 cells with BMP2 induced MMP-2 secretion and activation, associated with decreased E-cadherin expression, resulting in epithelial-to-mesenchymal transformation (EMT) and cell invasion. Blockade of ROS by the ROS scavenger, 2-MPG, abolished cell invasion, inhibited the EMT process and decreased MMP-2 expression, suggesting ROS accumulation caused an increase in MMP-2 expression in BMP2-stimulated PANC-1 cell invasion. Furthermore, treatment of PANC-1 cells with 2-MPG or ERK inhibitor PD98059 reduced the phosphorylation of ERK, resulting in attenuation of BMP2-induced cell invasion and MMP-2 activation. Taken together, these results suggest that BMP2 induces the cell invasion of PANC-1 cells by enhancing MMP-2 secretion and acting through ROS accumulation and ERK activation.

The origins of vacularization in tumors.

Vascularization is crucial for tumor growth and metastasis. Angiogenesis and vasculogenesis are widely accepted processes of tumor vascularization, particularly for endothelium-dependent vessels. In both these processes, the tumor vascular endothelial cells are derived from the host cells, including cells in normal tissues around the tumor or endothelial progenitor cells. In addition, the mosaic vessels occur as a transitional pattern between endothelium-dependent vessels and vasculogenic mimicry (VM), wherein both host endothelium and tumor cells participate in tumor vascularization. VM provides a special passage not involving endothelial cells and is conspicuously different from angiogenesis and vasculogenesis. The biological features of the tumor cells that form VM remain unknown. Tumor stem cells may participate in VM. In this review, we discuss the patterns involved in the origin of vascularization in tumors.

MicroRNA155 is induced in activated CD4(+) T cells of TNBS-induced colitis in mice.

AIM: To investigate the expression of microRNA155 (miRNA155) in trinitrobenzene sulphonic acid (TNBS)-induced colitis and the relationship between miRNA155 and tumor necrosis factor (TNF) expressions. METHODS: In TNBS colitis mice, miRNA155 and TNF mRNA expressions were measured in colons and CD4(+) T cells of draining lymph nodes (LNs). CD4(+) T cells were cultured in vitro with or without anti-CD3/CD28 antibody, and the expressions of miRNA155 and TNF mRNA in cells and TNF concentration in culture media were examined. RESULTS: miRNA155 and TNF mRNA expressions in colons and in cells of LNs were significantly increased in TNBS colitis compared with controls. In TNBS colitis, miRNA155 and TNF mRNA expressions in CD4(+) T cells of LNs and TNF concentration in CD4(+) T cells culture media increased compared with controls. When cultured with anti-CD3/CD28 antibody, miRNA155 and TNF mRNA expressions in CD4(+) T cells and TNF concentration in the CD4(+) T cells culture media were significantly higher than those cultured without anti-CD3/CD28 antibody. Following analysis using the Pearson's correlation coefficient, miRNA155 expression had a significant positive correlation with either TNF mRNA expression in CD4(+) T cells (r = 0.860, P < 0.05) or TNF concentration in CD4(+) T cells culture media (r = 0.892, P < 0.05). CONCLUSION: miRNA155 is induced in colons and activated CD4(+) T cells in TNBS colitis, and the levels of miRNA155 and TNF expressions have a significant positive correlation.