ObjectiveTo investigate the effect of Lactobacillus plantarum (LP) on the intestinal barrier function under inflammation. MethodsInterleukin-10 knockout (IL-10－/－) mice were used as the model of inflammatory bowel disease. IL-10－/－ and wild type (WT) mice received the LP or Ringer solutions for 4 weeks. Colitis was assessed by histological score and clinical manifestation was observed. The gut paracellular permeability was measured by Ussing chamber. The concentrations of tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) were detected by the ELISA method. The expressions and distributions of tight junction proteins were determined by Western blot and immunofluorescence, respectively. ResultsCompared with the WT group, the diarrhea, rectal prolapse, and weight loss were obvious (Plt;0.01), the concentrations of TNF-α and IFN-γ significantly increased (Plt;0.01), the infiltration of numerous inflammatory cells, even transmural ulcers, and crypt abscess were observed, the ultrastructure of tight junction was damaged, the mannitol permeability significantly increased (Plt;0.001) and transepithelial resistance (TER) significantly decreased (Plt;0.001), and the expressions of tight junction proteins (ZO-1, occludin, and claudin-1) significantly decreased (Plt;0.01) in the IL-10－/－ group. Compared with the IL-10－/－ group, the clinical and pathological manifestations of colitis significantly improved (Plt;0.01), the ultrastructural damage of tight junction was prevented, the mannitol permeability significantly decreased (Plt;0.001) and the TER significantly increased (Plt;0.001), the concentrations of TNF-α and IFN-γ significantly decreased (Plt;0.01), and the expressions of tight junction proteins (ZO-1, occludin, and claudin-1) significantly increased (Plt;0.01) in the IL-10－/－+LP group. ConclusionTreatment with LP ameliorates colonic epithelial barrier dysfunction by promoting the expressions of tight junctional proteins in IL-10－/－ mice.
Objective To investigate the expression of claudin-1 in breast tumor tissues and the relationship of development and progress of breast neoplasm．Methods The expressions of claudin-1 in 89 cases of breast cancer and 37 benign breast diseases were tested by tissue chip technology and immunohistochemistry．The relationships of claudin-1 expression to the lymph node metastasis，TNM staging，maximum diameter of the tumor，and histology grade were statistically analyzed．Results The expression of claudin-1 in the breast cancer was significantly lower than that in the benign breast disease（χ2=19.20，P=0.000 2）．The claudin-1 expression in the patients with lymph node metastasis was significantly lower than that without lymph node metastasis （χ2=3.85，P=0.049 7）．The claudin-1 expression in the stageⅢ of TNM staging was weaker than that in the stage Ⅰ（χ2=5.29，P=0.021 4） and stage Ⅱ （χ2=7.46，P=0.006 3），respectively. There was no significant difference of the claudin-1 expression in the different maximum diameters of tumor （χ2=1.58，P=0.453 8） or histology grades （χ2=1.02，P=0.600 5），respectively．Conclusions The expression of claudin-1 might be correlated with the occurrence，development，and metastasis in breast tumor．It may be one of the potential indicator for lymph node metastasis and prognosis assessment in breast cancer．
ObjectiveTo understand research progress of influence of claudins on proliferation and activation for breast cancer. MethodThe relevant literatures of influence of claudins on proliferation and activation for breast cancer were retrieved and reviewed. ResultsThe claudins had 24 members in mammals,claudin-13 was missing in human beings.Expression and distribution mode of the claudins possessed highly tissue-specific,and multiple proteins were expressed in many organizations.The expressions of claudins could be regulated from the levels of transcription and post-transcription,coordinately regulated by the transcription factor and post-synthetic modifications.Claudins were related to epithelial-mesenchymal transition.Now the studies were relatively clear those focused on claudin-1,-2,-4,-6,and other subtypes,and the expression of claudin-1 indicated the poor prognosis of tumor;claudin-2 was closely related to liver metastasis of breast cancer;claudin-4 was closely related to triple negative breast cancer;the function of claudin-6 in the breast cancer was controversial.In addition to the claudins mentioned above,other claudin members also played certain roles in normal breast and malignant breast tumors.Claudin-5 might participate in metastasis of breast cancer through N-WASP and ROCK signal pathway;CD-24 and claudin-7 immunodepression had a certain guiding significance on prognosis of invasive ductal carcinoma;the expressions of claudin-16 and HAPLN3 gene were remarkably increased in human breast cancer;Claudin-20 induced breast cancer cells into a subtype that possessed the high invasiveness and weakened the resis-tance of epithelial-mesenchymal transition.Recently,the claudin-low subtype was proposed,and it differed from other types of breast cancer in many aspects,and also it had a better prognosis than other types of triple negative breast cancer. ConclusionsClaudin,being an important member of tight junction protein,is confirmed to be related to epithelial-mesenchymal transition.Claudins play important roles in dissociaton,activation,invasiveness,and metastasis of breast cancer,but there is no final conclusion which member contributes to invasiveness and metastasis of breast cancer.Moreover,there are opposite conclusions on some certain claudins members in breast cancer which might due to the different subtypes of breast cancer,so,further studies about the function of claudins in different subtypes are needed eagerly.