Silencing of Prrx2 Inhibits the Invasion and Metastasis of Breast Cancer both In Vitro and In Vivo by Reversing Epithelial-Mesenchymal Transition.

BACKGROUND/AIMS: Epithelial-mesenchymal transition (EMT) is recognized as a crucial mechanism in breast cancer progression and metastasis. Paired-related homeobox 2 (Prrx2) has been identified as a new EMT inducer in cancer, but the underlying mechanisms are still poorly understood. METHODS: The expression of Prrx2 was assessed by immunohistochemistry in breast cancer tissues to evaluate the clinicopathological significance of Prrx2, as well as the correlation between Prrx2 and EMT. Short hairpin RNA knockdown of Prrx2 was used to examine cellular effects of Prrx2, detecte the expression of Wnt/ß-catenin signaling and EMT-associated proteins, and observe cell proliferation, invasion and migration abilities in vitro and in vivo. RESULTS: Clinical association studies showed that Prrx2 expression was related to tumor size, lymph node metastasis, tumor node metastasis stages, EMT and poor survival. Results also showed that knockdown of Prrx2 could alter cell morphology, suppressed the abilities of cell proliferation, invasion and migration in breast cancer. Moreover, silencing of Prrx2 induced the mesenchymal-epithelial transition and prevented nuclear translocation of ß-catenin, inhibited wnt/ß-catenin signaling pathway. CONCLUSION: Our study indicated that Prrx2 may be an important activator of EMT in human breast cancer and it can serve as a molecular target of therapeutic interventions for breast cancer.

Notch signaling mediated by TGF-ß/Smad pathway in concanavalin A-induced liver fibrosis in rats.

AIM: To explore the exact interaction between Notch and transforming growth factor (TGF)-ß signaling in liver fibrosis. METHODS: We established a rat model of liver fibrosis induced by concanavalin A. Peripheral blood mononuclear cells (PBMCs) were isolated from the modeled rats, and cultured with γ-secretase inhibitor DAPT and TGF-ß inhibitor for 24 h. The mRNA levels of Notch and TGF-ß signaling were detected by quantitative real-time polymerase chain reaction. Expression of Notch and TGF-ß proteins was analyzed by western blotting. RESULTS: Compared to control rats, Notch and TGF-ß signaling was activated in PBMCs of model rats. Administration of DAPT and TGF-ß inhibitor suppressed Notch and TGF-ß signal transducer in PBMCs of model rats. DAPT reduced mRNA and protein expression of TGF-ß signaling, such as TGF-ß1 and Smad3. TGF-ß inhibitor also downregulated Notch1, Hes1 and Hes5, and mRNA and protein expression of the Notch signaling pathway. CONCLUSION: Notch and TGF-ß signaling play a role in liver fibrosis. TGF-ß signaling upregulates Notch signaling, which promotes TGF-ß signaling.

Lack of an association between XRCC2 R188H polymorphisms and breast cancer: an update meta-analysis involving 35,422 subjects.

PURPOSE: Several studies have investigated the associations between XRCC2 R188H polymorphism and the susceptibility to breast cancer, but the results have been inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed. METHODS: PubMed and China National Knowledge Infrastructure (CNKI) searches were carried out for relevant studies published before March 2015. Meta-analysis was performed with the Stata, version 11.0. RESULTS: A total of 17 case-control studies, including 17,986 cases and 17,436 controls, were selected. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association in the homozygous model, dominant model, and recessive model. When all the studies were pooled into the meta-analysis, there was no evidence showing a significant association between XRCC2 R188H polymorphism and breast cancer risk (for homozygous model, OR=0.84, 95% CI=0.62-1.14; for dominant model: OR=0.76, 95% CI=0.53-1.09; and for recessive model: OR=1.04, 95% CI=0.98-1.10). In the subgroup analysis by ethnicity, no significant association was found between the polymorphism and breast cancer risk. CONCLUSIONS: In conclusion, this meta-analysis indicates that the XRCC2 R188H polymorphism is not a risk factor for developing of breast cancer.

Regional tissue immune responses after sciatic nerve injury in rats.

Inflammatory cells play a critical role during nerve regeneration following peripheral nerve injury. In this study, we investigated immune responses in rat sciatic nerve after injury. Wistar rats were randomly divided into the sciatic nerve injury (model) group and control group. The right sciatic nerve of rats in the model group was transected and sutured end-to-end. Our results showed that rats in the model group functionally recovered following sciatic nerve injury. We detected inflammatory cell infiltration in the remaining sciatic nerves following injury. In addition, expression of interferon-γ (INF-γ), interleukin-10 (IL-10), and the INF-γ/IL-10 ratio was significantly elevated one week following nerve injury, but gradually decreased thereafter. Our findings demonstrate that immune responses and inflammatory cell activation are involved during recovery from sciatic nerve injury.

[Expression Changes of Matrix Reconstitution-related Genes in Bone Marrow during 5-Fluorouracil-Induced Hemopoietic Injury and Their Significance].

OBJECTIVE: To explore the expression change of the genes related with matrix reconstitution during the injury and reconstitution of murine bone marrow following treatment with 5-fluorouracil (5-FU). METHODS: C57BL/6 mice received intraperitoneal injection of 5-FU (200 mg/kg), and peripheral blood cell counts were monitored at 3, 6, 9, 15, 21, 27 days after treatment. Bone marrow cells were harvested at these times for total RNA extraction using TRIzol. Reverse transcriptions in combination with real-time PCR were performed for detecting expression of genes related with matrix reconstitution, including ECM-1, MMP-2, MMP-3, MMP-13 and TIMP-1. RESULTS: After injection of 5-FU, the numbers of three line cells in peripheral blood (i.e. RBC, WBC and platelets) decreased and then recovered with differential dynamics. Similarly, RT-qPCR revealed that all the 5 detected gene expressions were significantly up-regulated during the injury. The mRNA expression of MMP-2 reached to peak at day 3 while the other genes reached to peak at day 6. MMP-3 has a low expression when compared with others, but its expression increased significantly after injury. CONCLUSION: In 5-FU induced hematopoietic injury and reconstitution model, matrix reconstitution-related genes may play an important role in hematopoietic reconstitution, but different genes play different roles at various time, and cooperate with each other for hematopoietic reconstitution.

Preventive effect of halofuginone on concanavalin A-induced liver fibrosis.

Halofuginone (HF) is an active component of extracts derived from the plant alkaloid febrifugine and has shown therapeutic promise in animal models of fibrotic disease. Our main objectives were to clarify the suppressive effect of HF on concanavalin A (ConA)-induced liver fibrosis. ConA injection into the tail vein caused a great increase in the serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, while orally administration of HF significantly decreased the levels of the transaminases. In addition, the levels of hyaluronic acid (HA), procollagen III (PCIII) and TGF-ß1 in the serum and collagen I, α-SMA, tissue inhibitors of metalloproteinase 2 (TIMP2) and Smad3 in the liver tissue were significantly lowered with the treatment of HF. Histological examination also demonstrated that HF significantly reduced the severity of liver fibrosis. Since ConA-induced liver fibrosis is caused by the repeated activation of T cells, immunomodulatory substances might be responsible for the suppressive effect of HF. We found that the production of nuclear factor (NF)-kB in the serum was increased in ConA-treated group, while decreased significantly with the treatment of HF. The changes of inflammatory cytokines tumor necrosis factor (TNF-α), IL-6 and IL-1ß in the serum followed the same rhythm. All together, our findings indicate that orally administration HF (10ppm) would attenuate the liver fibrosis by suppressing the synthesis of collagen I and inflammation-mediated liver injury.