Background: Salvia bowleyana, S. splendens, and S. officinalis are globally distributed and have been widely used to treat coronary heart disease, liver tumors, and viral diseases. To systematically determine their phylogenetic relationship and develop molecular markers for species determination, we sequenced and assembled their chloroplast genomes, and analyzed the genome characteristics. Moreover, we compared the phylogenetic specification and divergence genes fragments of chloroplast genomes from the three Salvia species. Results: The length of S. bowleyana, S. splendens, and S. officinalis chloroplast genomes were 151387 bp, 150604 bp, and 151163 bp, respectively. The sizes of the large-single copy, small-single copy, and inverted repeat regions were 82772 bp, 17573 bp, and 51042 bp for S. bowleyana; 82181 bp, 17857 bp, and 50566 bp for S. splendens; 82429 bp, 17510 bp, and 51224 bp for S. officinalis, respectively. The GC contents of the three chloroplast genomes were 38.01%, 38.04%, 38.04%, partly. In the comparison of chloroplast genomes from Lamiaceae family, the six genes ndhB, rpl2, rpl23, rps7, rps12, and ycf2 were present in the IRs regions of all 41 chloroplast genomes in the Lamiaceae family. We found that one of the gene rpl20 was intact and stably occurred in all 41 species chloroplast genomes, however, another pseudogene one was lost in that of 40 species except the Dracocephalum heterophyllum. For the repeat analysis, 29 tandem repeats, 35, 29, 24 simple-sequence repeats(SSRs), and 47, 49, 40 interspersed repeats were identified in the three Salvia species chloroplast genomes based on the diverse requirements. The three specific intergenic sequences(IGS) of rps16-trnQ-UUG, trnL-UAA-trnF-GAA, and trnM-CAU-atpE were found to discriminate the certain species by comparing 23 Salvia chloroplast genomes. Six genes including rpl22, rps19, rpl2, ycf1, ndhF, and psbA were found in the highly diverse IR boundary regions. The genetic distance analysis of IGS showed the trnL-UAG-ccsA, rps16-trnQ-UUG, ccsA-ndhD, rps15-ycf1, and ndhE-ndhG regions had the higher variability. Furthermore, the phylogenetic tree inferred that the 23 Salvia species formed a monophyletic group. Lastly, two pairs of Genus-specific DNA barcode primers were identified, which can be used to amplify the part sequence of trnM-CAU-atpE and ccsA-ndhD region. Conclusions: We acquired the complete chloroplast genome of the three Salvia species, which will provide a solid foundation to understand their phylogenetic status in Salvia genus. Moreover, the research can provide the probability to discriminate the Salvia species compared with the genomics between the phenotype and the distinction of gene fragments .

Background: The aim of this work was to screen and validate biomarkers of ovarian cancer-initiating cells to detect the mechanisms of recurrence of epithelial ovarian cancer (EOC). Methods: Stably labelled the amino acid in side population (SP) cells of epithelial ovarian cancer which were rich in cancer-initiating cells and non-SP cells with isotope in culture and differentially expressed cellular membrane proteins in SP cells were identified through proteomics technology. The new candidate biomarker was screened and validated through RT-PCR and western blot. Both in cell lines and primary EOC, cancer-initiating biofunctions of CDC50A positive cells were validated. Moreover, the characteristics of mesenchymal transition (EMT) was also detected and the correlation between the biomarker and clinical prognosis was observed. Results: Through proteomics technology, candidate protein CDC50A was screened, and its significantly differential expression in SP cells was validated. CDC50A-positive cells from cell lines and primary ovarian cancer tissues were validated to show characteristics of cancer-initiating cells both in vitro and in vivo, including sphere-forming, self-renewal, differentiation, tumor metastasis and tumorigenicity in mice. The relationship between CDC50A-positive cells from primary tissues and tumor metastasis was confirmed based on their mesenchymal transition characteristics. Among 16 high-grade ovarian serous cancer patients, a high ratio of CDC50A-positive cells in primary tumours was correlated with a shorter platinum-free interval (p=0.031, RR 0.260, 95% CI 0.77~0.885). Conclusion: CDC50A might be a novel cell surface biomarker for epithelial ovarian cancer-initiating cells and could be a new target to resolve tumour development in EOC patients.