Migratory insertion of copper-allenylidene from propargyl ester.

The highly efficient copper-catalyzed homo-dimerization and cross-coupling of propargyl esters have been developed. Various 1-en-3,5-diynes, [5]cumulenes and 1,3-diynes were successfully furnished via the copper-allenylidene intermediates with moderate to excellent yields. Migratory insertion is proposed as the key step to achieve the selectivity at the carbene carbon of the copper-allenylidene.

Recent progress on donor and donor-donor carbenes.

Donor and donor-donor carbenes are two important kinds of carbenes, which have experienced tremendous growth in the past two decades. This review provides a comprehensive overview of the recent development of donor and donor-donor carbene chemistry. The development of this chemistry offers efficient protocols to construct a wide variety of C-C and C-X bonds in organic synthesis. This review is organized based on the different types of carbene precursors, including diazo compounds, hydrazones, enynones, cycloheptatrienes and cyclopropenes. The typical transformations, the reaction mechanisms, as well as their subsequent applications in the synthesis of complex natural products and bioactive molecules are discussed. Due to the rapidly increasing interest in this area, we believe that this review will provide a timely and comprehensive discussion of recent progress in donor and donor-donor carbene chemistry.

[miR-520a regulates ErbB4 expression and suppresses proliferation and invasion of esophageal squamous cell carcinoma].

OBJECTIVE: To investigate the role of miR-520a in regulation ErbB4 expression and the biological behavior of esophageal squamous cell carcinoma (ESCC). METHODS: The role of miR-520a in regulating the expression of ErbB4 was investigated by Western blotting and luciferase reporter assay system. The effect of miR-520a on the proliferation and invasion of ESCC cells was detected by MTT and Transwell invasion assay, respectively. RESULTS: Western blotting and luciferase reporter assay revealed that miR-520a down-regulated the expression of ErbB4 in vitro. miR-520a significantly inhibited the proliferation and suppressed the invasion of ESCC cell line Eca109. CONCLUSION: miR-520a regulates the expression of ErbB4 and suppresses the proliferation and invasion of ESCC cells in vitro, suggesting its role as a tumor suppressor.

miR-302b is a potential molecular marker of esophageal squamous cell carcinoma and functions as a tumor suppressor by targeting ErbB4.

BACKGROUND: ErbB4 expression has been noted in various tumors, but its regulatory mechanism in esophageal squamous cell carcinoma (ESCC) remains unclear. The aim of this study was to investigate whether miR-302b regulates the expression of ErbB4 at the post-transcriptional level and to determine its expression, significance, and function in ESCC. METHODS: We used real-time reverse transcriptase-polymerase chain reaction to quantify the expression of miR-302b in 50 ESCC tissues and analyzed its relationship with clinicopathological factors and survival. Then, we investigated the post-transcriptional regulation of ErbB4 expression using immunoblot analysis and luciferase reporter assays. Finally, the effects of miR-302b on proliferation, apoptosis, and invasion of ESCC cells was detected using MTT, flow cytometric analysis, and transwell invasion assays, respectively. RESULTS: miR-302b was significantly down-regulated and correlated with tumor differentiation and lymph node metastasis in ESCC. Univariate and multivariate analyses indicated that low miR-302b expression might be a poor prognostic factor. Further studies demonstrated that miR-302b post-transcriptionally down-regulated the expression of ErbB4 in vitro. Moreover, miR-302b inhibited proliferation by inducing apoptosis and repressed invasion in the ESCC cell lines. CONCLUSIONS: miR-302b is a potential molecular marker of ESCC and functions as a tumor suppressor by post-transcriptionally regulating ErbB4.

Preventive effect of ulinastatin on postoperative complications, immunosuppression, and recurrence in esophagectomy patients.

BACKGROUND: To evaluate the potential efficacy of preventive effect of ulinastatin in esophagectomy patients. METHODS: Eighty patients with esophageal cancer were preoperatively allocated at random into two equal groups. Ulinastatin was administered to the treatment group (U) whereas the control group (C) received a placebo. The arterial oxygen tension and carbon dioxide tension were measured and the respiratory index (RI) was calculated. Plasma levels of circulating T lymphocyte subsets and interleukin 6 (IL-6) were measured and clinical courses of patients in the two groups were compared. RESULTS: RI in the U group was significantly lower than that in the C group. The rate of postoperative complications and the duration of ICU stay were significantly lower in the U group. Ulinastatin significantly increased the rate of CD3+ and CD4+ cells, and ratio of CD4+/CD8+, but decreased the rate of CD8+ cells and release of IL-6 compared to the C group on postoperative days 1 and 3. Patients within the C group showed worse recurrence free survival. Multivariate analysis revealed that ulinastatin administration significantly decreased the incidence of recurrence. CONCLUSIONS: Ulinastatin had a preventive effect on postoperative complications and immunosuppression in esophagectomy patients, thereby prolongingrecurrence free survival.