三叶因子3研究进展

Treatment with intestinal trefoil factor regulates TLR2/4 and NF-κB expression and protects against LPS-induced intestinal injury in rats

AIM: To investigate whether intestinal trefoil factor (ITF) regulates the expression of Toll-like receptor (TLR) 2/4 and nuclear factor-κB (NF-κB) and exerts a protective effect against lipopolysaccharide (LPS)-induced intestinal injury in rats.

METHODS: Twenty-four 10-day-old Wistar rats were randomly and equally divided into three groups: control group (intraperitoneally injected with normal saline 1 mL/kg ), endotoxemia group (intraperitoneally injected with LPS 5 mg/kg), and LPS + ITF group (intraperitoneally injected with LPS 5 mg/kg and recombinant ITF 0.1 mL/per rat). Rats were sacrificed 3 h after injection. A segment of the distal ileum was dissected for hematoxylin-eosin staining. Pathological changes in the small intestine were observed under an optical microscope. The mRNA and protein expression of TLR2/4 and NF-κB was detected by RT-PCR and immunohistochemistry, respectively.

RESULTS: The structure of the small intestine of rats in the control group was normal. Inflammatory cell infiltration and interstitial/epithelial edema were observed in rats in the LPS group and LPS + ITF group, and the pathological changes were significantly milder in the LPS + ITF group than in the LPS group. The expression of TLR2 mRNA and protein in the LPS + ITF group was significantly higher than that in the LPS group (7.453 ± 1.90 vs 3.069 ± 0.08, 52.125 ± 4.1 vs 20.688 ± 2.4, both P < 0.01). The expression of TLR4 and NF-κB mRNAs and proteins in the LPS + ITF group was significantly lower than that in the LPS group (TLR4 mRNA: 5.373 ± 1.18 vs 16.711 ± 1.28, P< 0.01; TLR4 protein: 16.338 ± 4.98 vs 22.760 ± 3.68, P< 0.01; NF-κB mRNA: 0.533 ± 0.05 vs 2.228 ± 0.72, P< 0.01; NF-κB protein: 36.526 ± 9.18 vs 50.433 ± 3.37, P< 0.05).

CONCLUSION: Treatment with ITF protects against LPS-induced intestinal injury in rats possibly via mechanisms associated with down-regulation of TLR4 and NF-κB expression.

Expression of trefoil factor family-3 and β-catenin in different types of colorectal mucosal lesions

AIM: To analyze the expression of trefoil factor family-3 (TFF3) and β-catenin in different types of colorectal mucosal lesions and to explore their role in the development and progression of colorectal adenocarcinoma and adenoma.

METHODS: The expression of TFF3 and β-catenin was detected by immunohistochemistry in 20 normal colorectal mucosa specimens, 30 colorectal polyp specimens, 20 colorectal adenoma (CRA) specimens, 20 colorectal adenoma (with atypical hyperplasia, CRAAH) specimens, and 40 colorectal adenocarcinoma (CRCA) specimens. The differences in the expression of TFF3 and β-catenin in different types of colorectal mucosal lesions were compared.

RESULTS: The positive rate of TFF3 expression was significantly lower in CRA and CRAAH (P < 0.05), but higher in CRCA. The abnormal expression of β-catenin were gradually increasing along with the sequence of CRA→CRAAH→CRAC, the membrane expressing deletion and ectopic expression were both higher in CRAC than in CRCP and CRA (60.00% vs 0.00%, 15.00%; 75.00% vs 0.00%, 40.00%, all P < 0.05). TFF3 expression was not correlated with tumor location or differentiation in CRAC, but was related to lymph node metastasis and Duke's stage (both P < 0.05). β-catenin expression was not correlated with tumor location or lymph node metastasis, but was related to tumor differentiation. Ectopic expression of β-catenin was related to Duke's stage (P < 0.05). There were significantly positive correlations between TFF3 expression and abnormal expression and loss of membrane expression of β-catenin in CRA (r = 0.427, P = 0.006; r = 0.577, P = 0.000) but not in CRAC (r = 0.015, P = 0.951; r = 0.385, P = 0.094). There was a significantly positive correlation between loss of membrane expression and ectopic expression of β-catenin in CRAC and CRA (r = 0.638, P = 0.000; r = 0.514, P = 0.020).

CONCLUSION: The expression of TFF3 and β-catenin is closely related with the development and progression of CRAC. They may be involved in an early event in colorectal carcinogenesis. TFF3 is related to the abnormal expression of β-catenin, both of which may be involved in the development and progression of CRAC.

Trefoil factor: implications for clinical laboratory diagnostics

Trefoil factors (TFF), expressed physiologically in the secretory cells of gastrointestinal mucosa and other mucosal tissues, compose a unique peptide family with important biologic functions. Aberrant expression and/or continued secretion of TFF might exist concurrently with the processes of digestive system inflammation, tumor or other related pathological changes. Previous pathological studies have shown that the abnormal expression of TFF is associated with the prognosis of digestive system diseases. The results obtained from gene expression profiling, tumor secretomics and bioinformatic analysis have positively confirmed that clinical detection of TFF peptides or mRNAs has an excellent diagnostic performance to detect digestive system diseases, especially for the monitoring of recurrence or metastasis of tumors and for the estimation of therapeutic efficacy and prognosis. Therefore, TFF is a potential biomarker for diagnosis, treatment and prognosis of digestive system diseases.