HuR promotes breast cancer cell proliferation and survival via binding to CDK3 mRNA.

HuR, a ubiquitously expressed RNA-binding protein, stabilizes mRNA and regulates its translation. HuR expression was increased at all stages of breast cancer and correlated with poor clinical outcome. However, the detailed mechanisms remain unclear. Here we reported that overexpression of HuR increased CDK3 mRNA stability and thus its protein expression in MDA-MB-231 and MCF-7 cells. Mechanistically, CDK3 mRNA was identified as a target of HuR via bioinformatics and RNA binding protein immunoprecipitation (RIP) assays. Furthermore, treatment with HuR shRNA decreased CDK3 expression, inhibited cell proliferation and promoted cell apoptosis in breast cancer. More importantly, overexpression of CDK3 reversed the suppressive effects of HuR knockdown on cell growth in both MDA-MB-231 and MCF-7 cells. Finally, HuR and CDK3 expression levels were positively correlated and significantly up-regulated in breast cancer samples. And overexpression of HuR attenuated the chemotherapeutical efficiency of breast cancer. Therefore, our results indicate that ectopic expression of HuR promotes breast cancer cell proliferation and survival by directly binding to and stabilizing CDK3 mRNA.

Antibacterial Meroterpenoids from the South China Sea Sponge Dysidea sp.

Chemical investigation of the sponge Dysidea sp. afforded three new sesquiterpene phenols (1-3) and one new sesquiterpene aminoquinone (4), together with four known sesquiterpene derivatives (5-8). The structures of all compounds were unambiguously elucidated by extensive spectroscopic analysis, as well as by comparison with the literature. The absolute configurations of compounds 1-4 were determined by electron capture detector (ECD) calculations and circular dichroism (CD) spectrum analysis. Their antibacterial activity against Escherichia coli (25922), Bacillus subtilis (6633), and Staphylococcus aureus (25923) were evaluated. Compounds 1 and 3 showed weak antibacterial activity against the above three strains, whereas compounds 4-8 showed potent antibacterial activities with minimum inhibitory concentration (MIC) values in the range of 3.125 to 12.5 µg/mL.

Correlation-based motion vector processing with adaptive interpolation scheme for motion-compensated frame interpolation.

In this paper, we address the problems of unreliable motion vectors that cause visual artifacts but cannot be detected by high residual energy or bidirectional prediction difference in motion-compensated frame interpolation. A correlation-based motion vector processing method is proposed to detect and correct those unreliable motion vectors by explicitly considering motion vector correlation in the motion vector reliability classification, motion vector correction, and frame interpolation stages. Since our method gradually corrects unreliable motion vectors based on their reliability, we can effectively discover the areas where no motion is reliable to be used, such as occlusions and deformed structures. We also propose an adaptive frame interpolation scheme for the occlusion areas based on the analysis of their surrounding motion distribution. As a result, the interpolated frames using the proposed scheme have clearer structure edges and ghost artifacts are also greatly reduced. Experimental results show that our interpolated results have better visual quality than other methods. In addition, the proposed scheme is robust even for those video sequences that contain multiple and fast motions.