To construct an East Asia mitochondrial DNA (mtDNA) phylogeny, we sequenced the complete mitochondrial genomes of 672 Japanese individuals (http://www.giib.or.jp/mtsnp/index_e.html). This allowed us to perform a phylogenetic analysis with a pool of 942 Asiatic sequences. New clades and subclades emerged from the Japanese data. On the basis of this unequivocal phylogeny, we classified 4713 Asian partial mitochondrial sequences, with <10% ambiguity. Applying population and phylogeographic methods, we used these sequences to shed light on the controversial issue of the peopling of Japan. Population-based comparisons confirmed that present-day Japanese have their closest genetic affinity to northern Asian populations, especially to Koreans, which finding is congruent with the proposed Continental gene flow to Japan after the Yayoi period. This phylogeographic approach unraveled a high degree of differentiation in Paleolithic Japanese. Ancient southern and northern migrations were detected based on the existence of basic M and N lineages in Ryukyuans and Ainu. Direct connections with Tibet, parallel to those found for the Y-chromosome, were also apparent. Furthermore, the highest diversity found in Japan for some derived clades suggests that Japan could be included in an area of migratory expansion to Continental Asia. All the theories that have been proposed up to now to explain the peopling of Japan seem insufficient to accommodate fully this complex picture

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Objective: The diagnosis of mitochondrial disorders (MDs) is occasionally difficult because patients often present with solitary, or a combination of, symptoms caused by each organ insufficiency, which may be the result of respiratory chain enzyme deficiency. Growth differentiation factor 15 (GDF-15) has been reported to be elevated in serum of patients with MDs. In this study, we investigated whether GDF-15 is a more useful biomarker for MDs than several conventional biomarkers. Methods: We measured the serum levels of GDF-15 and fibroblast growth factor 21 (FGF-21), as well as other biomarkers, in 48 MD patients and in 146 healthy controls in Japan. GDF-15 and FGF-21 concentrations were measured by enzyme-linked immunosorbant assay and compared with lactate, pyruvate, creatine kinase, and the lactate-topyruvate ratio. We calculated sensitivity and specificity and also evaluated the correlation based on two rating scales, including the Newcastle Mitochondrial Disease Rating Scale (NMDAS). Results: Mean GDF-15 concentration was 6-fold higher in MD patients compared to healthy controls (2,711 6 2,459 pg/ml vs 462.5 6 141.0 pg/mL; p < 0.001). Using a receiver operating characteristic curve, the area under the curve was significantly higher for GDF-15 than FGF-21 and other conventional biomarkers. Our date suggest that GDF-15 is the most useful biomarker for MDs of the biomarkers examined, and it is associated with MD severity. Interpretation: Our results suggest that measurement of GDF-15 is the most useful first-line test to indicate the patients who have the mitochondrial respiratory chain deficiency.

MiR-34a and its downstream targets SIRT1 and Bcl2 play important roles in the development of paclitaxel resistance, all of which can be useful biomarkers and promising therapeutic targets for the drug resistance in hormone-refractory prostate cancer.

MicroRNAs are involved in cancer pathogenesis and act as tumor suppressors or oncogenes. It has been recently reported that miR-148a expression is down-regulated in several types of cancer. The functional roles and target genes of miR-148a in prostate cancer, however, remain unknown. In this report, we showed that miR-148a expression levels were lower in PC3 and DU145 hormone-refractory prostate cancer cells in comparison to PrEC normal human prostate epithelial cells and LNCaP hormone-sensitive prostate cancer cells. Transfection with miR-148a precursor inhibited cell growth, and cell migration and invasion, and increased the sensitivity to anti-cancer drug paclitaxel in PC3 cells. Computer-aided algorithms predicted mitogen-and stress-activated protein kinase, MSK1, as a potential target of miR-148a. Indeed, miR-148a overexpression decreased expression of MSK1. Using luciferase reporter assays, we identified MSK1 as a direct target of miR-148a. Suppression of MSK1 expression by siRNA, however, showed little or no effects on malignant phenotypes of PC3 cells. In PC3PR cells, a paclitaxel-resistant cell line established from PC3 cells, miR-148a inhibited cell growth, and cell migration and invasion, and also attenuated the resistance to paclitaxel. MiR-148a reduced MSK1 expression by directly targeting its 3-UTR in PC3PR cells. Furthermore, MSK1 knockdown reduced paclitaxel-resistance of PC3PR cells, indicating that miR-148a attenuates paclitaxel-resistance of hormone-refractory, drug-resistant PC3PR cells in part by regulating MSK1 expression. Our findings suggest that miR148a plays multiple roles as a tumor suppressor and can be a promising therapeutic target for hormone-refractory prostate cancer especially for drug-resistant prostate cancer. MicroRNAs (miRNAs)2 are small non-coding RNAs composed of about 22-24 nucleotides and control protein expression through translational inhibition or mRNA degradation by binding to the 3Ј-untranslated region (3Ј-UTR) of target mRNAs (1). miRNAs regulate a number of biological processes such as development, proliferation, differentiation, and apoptosis. Aberrant expression of miRNA has been reported in a variety of cancers, some of which have been shown to act as tumor suppressors or oncogenes (2).MiR-148a expression is down-regulated in human breast cancer and undifferentiated gastric cancer (3, 4). DNA methylation-associated silencing of miR-148 expression is identified in human cancer cell lines established from lymph node metastasis of colon, melanoma, and head and neck cancer, suggesting its role for the development of metastasis (5). Direct targets of miR-148a so far reported include transcription growth factor-␤-induced factor 2 (TGIF2), DNA (cytosine-5-)-methyltransferase 3␤ (DNMT3b) and pregnane X receptor (PXR) (5-7). However, the functional roles and target genes of miR-148a in prostate cancer have not yet been documented.Mitogen-and stress-activated kinase 1 (MSK1), also known as ribosomal protein S6 kinase, 90kDa, polypeptide 5 (RPS6KA5), is a serine/threonine...