Objective:To establish a new type of small intestinal organoids with injury-related regenerative capacity, and to simulate the process of intestinal injury, regeneration, and repair in vitro. Methods:The crypt structures of ileal mucosa from 6 to 8 weeks old, 18 to 24 g specific pathogen-free C57BL/6 mice were isolated. The ENR, ENR+ tumor necrosis factor-α(TNF-α) and 8C culture systems were designed to establish small intestinal organoids under conditions of intestinal homeostasis, inflammatory injury and injury-related regeneration, and the morphology of intestinal organoids were observed. The cell types and spatial arrangements of intestinal organoids, and the expression of genes clusterin( Clu), annexin A1( Anxa1), stem cell antigen-1( Sca1) and regenerating islet-derived protein 3-beta( Reg3 b) at protein levels were detected by immunofluorescence staining. The expression of genes Clu, Anxa1, Sca1 and Reg3 b at mRNA levels were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Independent sample- t test was used for statistical analysis. Results:In ENR and 8C culture system, both intestinal organoids contained intestinal stem cells, goblet cells, Paneth cells and intestinal endocrine cells, and the spatial arrangement of cells was similar to the intestinal epithelium. In the 8C culture system, the amplification capacity of the new small intestinal organoids was significantly enhanced, the growth rate was faster, and the structure was larger and more complex than those of small intestinal organoids in ENR and ENR+ TNF-α culture systems. The results of qRT-PCR showed that, the relative mRNA expression levels of novel small intestinal organoid regeneration genes Clu, Anxa1, and Sca1 in the 8C culture system were higher than those in the ENR and ENR+ TNF-α culture systems (0.68±0.31 vs.0.20±0.07 and 0.36±0.19, 0.48±0.13 vs. 0.07±0.02 and 0.18±0.11, 0.56±0.20 vs. 0.02±0.01 and 0.08±0.04), and the differences were statistically significant ( t=4.82 and 2.77, 8.62 and 4.89, and 8.58 and 7.50; all P<0.05). The results of immunofluorescence staining indicated that, the expression levels of novel small intestinal organoid regeneration genes Clu, Anxa1, Sca1 and Reg3 b at protein level in the 8C culture system were higher than those in the ENR and ENR+ TNF-α culture systems (31.62±1.69 vs. 9.73±2.39 and 15.11±2.16, 42.65±1.85 vs. 19.70±1.18 and 24.97±2.82, 63.80±2.73 vs. 37.10±1.59 and 43.27±2.53, 53.26±1.84 vs. 27.75±3.78 and 33.16±3.50), and the differences were statistically significant( t=12.95 and 10.41, 18.13 and 9.09, 14.63 and 9.56, and 10.51 and 8.80; all P<0.001). Conclusion:The small intestinal organoids established in the novel culture system have the characteristics of injury-related regeneration, and provide a novel in vitro model for studying the regeneration of epithelial tissues and organs.

OBJECTIVETo explore the expression of NF-E1b in colorectal cancer tissues and its association with various clinicopathological parameters and prognosis of the patients.

METHODSClinicopathological and follow-up data of 168 colorectal cancer patients undergoing radical operation at Department of Gastrointestinal Surgery, Peking University Cancer Hospital and Institute from 2005 to 2012 were retrospectively analyzed, including 96 males and 72 females, with mean age of (57.8±11.2) years. The expression of NF-E1b protein was detected in samples of 168 resected colorectal cancer tissues and 45 adjacent non-cancerous tissues by immunohistochemistry. The expression rates of NF-E1b were compared among different clinicopathological features. Moreover, the association between NF-E1b expression and prognosis was analyzed.

RESULTSThe expression of NF-E1b protein located mainly in cytoplasm. Positive rate of NF-E1b expression in adjacent non-cancerous tissues was 17.8% (8/45), which was obviously lower than 67.9%(114/168) of cancer tissues with significant difference (χ(2)=36.376, P=0.000). Clinicopathological parameters analysis suggested that the expression level of NF-E1b in cancer tissues was associated with age (χ(2)=4.862, P=0.030), TNM staging (χ(2)=10.969, P=0.002), lymph node metastasis (χ(2)=7.390, P=0.008) and distal metastasis (χ(2)=17.887, P=0.000). The median follow-up time was 23(1-77) months. The overall 5-year survival of this cohort was 33.3%. Colorectal cancer patients with high levels of NF-E1b expression showed a worse overall survival compared with those with low levels of NF-E1b expression (18.4% vs. 56.6%, P=0.000). Univariate Cox regression analysis showed that tumor location (P=0.034), tumor size (P=0.003), TNM staging (P=0.000), depth of tumor invasion (P=0.009), lymph node metastasis (P=0.000), distant metastasis (P=0.000) and NF-E1b expression level (P=0.001) were associated with the prognosis of colorectal cancer patients. Multivariate Cox regression analysis revealed that tumor diameter >4 cm (HR=2.193,95% CI:1.334 to 3.603, P=0.002), distant metastasis (HR=2.064, 95% CI:1.160 to 3.672, P=0.014) and high NF-E1b expression (HR=1.994,95% CI:1.068 to 3.724, P=0.030) were independent risk factors of predicting poor prognosis of colorectal cancer patients.

CONCLUSIONSNF-E1b expression up-regulates in colorectal cancer tissues. High expression of NF-E1b is associated with poor prognosis of colorectal cancer patients. NF-E1b may serve as a potential target of the treatment for colorectal cancer.

Aged ; Biomarkers, Tumor ; metabolism ; Colorectal Neoplasms ; diagnosis ; metabolism ; Digestive System Surgical Procedures ; Female ; GATA2 Transcription Factor ; metabolism ; Gene Expression Regulation, Neoplastic ; Humans ; Immunohistochemistry ; Lymphatic Metastasis ; Male ; Middle Aged ; Neoplasm Staging ; Prognosis ; Retrospective Studies ; Risk Factors ; Up-Regulation