CircTHSD4 promotes the malignancy and docetaxel (DTX) resistance in prostate cancer by regulating miR-203/HMGA2 axis.

Objective: Circular ribose nucleic acids (circRNAs) are implicated in tumor progression and drug resistance of prostate cancer (PCa). The current work explored the function of circ_0005203 (circTHSD4) in the malignancy and docetaxel (DTX) resistance of PCa. Methods: circTHSD4 expression within PCa as well as matched non-carcinoma samples was measured through real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR). In addition, a subcellular fraction assay was conducted to determine circTHSD4 subcellular localization within PCa cells. In addition, we performed a Western blot (WB) assay to detect high-mobility-group A2 protein (HMGA2) levels. Besides, functional associations of two molecules were investigated through dual luciferase reporter assay. Cell Counting Kit (CCK)-8, colony formation together with Transwell assay was conducted to assess malignant phenotypes of PCa cells, whereas flow cytometry was performed to determine cell apoptosis. Furthermore, a xenograft mouse model was constructed to verify the effect of circTHSD4 on the carcinogenesis of PCa cells. Results: According to RT-qPCR results, circTHSD4 was up-regulated within PCa tissues and cells, which predicted the dismal prognostic outcome of PCa cases. circTHSD4 silencing within PCa cells markedly suppressed cell growth, migration, and colony formation. circTHSD4 silencing remarkably elevated PCa cell apoptosis and carcinogenesis within the xenograft model. Further, circTHSD4 silencing enhanced docetaxel (DTX) sensitivity in PCa cells. Furthermore, we demonstrated that circTHSD4 modulated the malignancy of PCa cells by regulating HMGA2 expression through sponging miR-203. Conclusion: Together, our findings suggest that circTHSD4 overexpression could promote the malignant phenotype and DTX resistance in PCa through the regulation of the miR-203/HMGA2 axis.

Genome assembly and transcriptome analysis provide insights into the antischistosome mechanism of Microtus fortis.

Microtus fortis is the only mammalian host that exhibits intrinsic resistance against Schistosoma japonicum infection. However, the underlying molecular mechanisms of this resistance are not yet known. Here, we perform the first de novo genome assembly of M. fortis, comprehensive gene annotation analysis, and evolution analysis. Furthermore, we compare the recovery rate of schistosomes, pathological changes, and liver transcriptomes between M. fortis and mice at different time points after infection. We observe that the time and type of immune response in M. fortis are different from those in mice. M. fortis activates immune and inflammatory responses on the 10th day post infection, such as leukocyte extravasation, antibody activation, Fc-gamma receptor-mediated phagocytosis, and the interferon signaling cascade, which play important roles in preventing the development of schistosomes. In contrast, an intense immune response occurrs in mice at the late stages of infection and could not eliminate schistosomes. Infected mice suffer severe pathological injury and continuous decreases in cell cycle, lipid metabolism, and other functions. Our findings offer new insights into the intrinsic resistance mechanism of M. fortis against schistosome infection. The genome sequence also provides the basis for future studies of other important traits in M. fortis.

The prognostic significance of DAPK1 in bladder cancer.

Bladder cancer is one of the leading causes of cancer-related death in men, however, there was only limited effective treatment for invasive bladder cancer. DAPK1 has been shown to play important role in apoptosis and autophagy to suppress cancer progression. Previous results have shown that DAPK1 promoter was hypermethylated in the majority of bladder cancer specimens, however, the prognostic significance of DAPK1 in bladder cancer has yet to be demonstrated. In the present study, we found that DAPK1 expression was negatively associated with tumor stage and a low level expression of DAPK1 in bladder cancer specimens were associated with shorter survival in bladder cancer patients in 3 independent bladder cancer datasets (n = 462). Further investigation showed that FGFR3 knockdown resulted in downregulation of DAPK1 in bladder cancer cell line, suggesting that FGFR3 may be an upstream factor of DAPK1. Further analysis of the 3 independent bladder cancer datasets have identified ACOX1, UPK2, TRAK1, PLEKHG6 and MT1X genes had their expression significantly correlated with that of DAPK1. Knockdown of DAPK1 in bladder cancer T24 cells resulted in downregulation of ACOX1, UPK2 and TRAK1. Interestingly, TRAK1, by itself, was a favorable prognostic marker in the 3 independent bladder cancer datasets. Importantly, by using connectivity mapping with DAPK1-associated gene signature, we found that vemurafenib and trametinib could possibly reverse DAPK1-associated gene signature, suggesting that inhibition of Raf/MEK pathway may be a potential therapeutic approach for bladder cancer. Indeed, treatment of vemurafenib in T24 bladder cancer cells resulted in upregulation of DAPK1 confirming our connectivity mapping, while knockdown of DAPK1 resulted in reduced sensitivity towards inhibition of Braf signaling by vemurafenib. Together, our results suggest that DAPK1 is an important prognostic marker and therapeutic target for bladder cancer and have identified possible therapeutic agents for future testing in bladder cancer models with low DAPK1 expression.

The complete mitochondrial genome of Microtus fortis calamorum (Arvicolinae, Rodentia) and its phylogenetic analysis.

Microtus fortis is a special resource of rodent in China. It is a promising experimental animal model for the study on the mechanism of Schistosome japonicum resistance. The first complete mitochondrial genome sequence for Microtus fortis calamorum, a subspecies of M. fortis (Arvicolinae, Rodentia), was reported in this study. The mitochondrial genome sequence of M. f. calamorum (Genbank: JF261175) showed a typical vertebrate pattern with 13 protein coding genes, 2 ribosomal RNAs, 22 transfer RNAs and one major noncoding region (CR region).The extended termination associated sequences (ETAS-1 and ETAS-2) and conserved sequence block 1 (CSB-1) were found in the CR region. The putative origin of replication for the light strand (O(L)) of M. f. calamorum was 35bp long and showed high conservation in stem and adjacent sequences, but the difference existed in the loop region among three species of genus Microtus. In order to investigate the phylogenetic position of M. f. calamorum, the phylogenetic trees (Maximum likelihood and Bayesian methods) were constructed based on 12 protein-coding genes (except for ND6 gene) on H strand from 16 rodent species. M. f. calamorum was classified into genus Microtus, Arvcicolinae for the highly phylogenetic relationship with Microtus kikuchii (Taiwan vole). Further phylogenetic analysis results based on the cytochrome b gene ranged from M. f. calamorum to one of the subspecies of M. fortis, which formed a sister group of Microtus middendorfii in the genus Microtus.

[Enrichment and screening of the microsatellite markers in Microtus fortis and its preliminary application in genetic diversity research].

This study was to isolate microsatellite markers from Microtus fortis genome by magnetic beads enrichments. Through hybridization of biotin-labeled microsatellite oligonucleotide probes, which were captured by streptavidin-coated magnetic with the adaptor-ligated enzyme-digested genome fragments, single-stranded DNA fragments containing microsatellites were obtained. After PCR amplification, these fragments were then cloned into T vectors and were transformed into competent cells subsequently. Ninety-two microsatellite sequences were randomly isolated from 70 positive clones. Twenty-one out of 27 pairs of designed microsatellite primers were screened out from the microsatellite sequences, and 10 out of the 21 microsatellite loci were used to investigate the genetic diversity of three populations of M. fortis, Hunan (wild), Hunan (domesticated), and Ningxia (domesticated). All the 10 microsatellite loci used to analyze the genetic diversity exhibited a good level of polymorphism. The values of observed number of alleles (Na), effective number of alleles (Ne), observed heterozygosity (Ho), expected heterozygosity (He) and polymorphic information content (PIC) were all the highest in the Hunan (wild) population, lower in the Hunan (domesticated) population, and the lowest in the Ningxia (domesticated) population.

Surface, interfacial and aggregation properties of sulfonic acid-containing gemini surfactants with different spacer lengths.

Four sulfonic acid-containing gemini surfactants 9BA-m-9BA (m=2, 3, 4, 6), 6,6'-(ethane-1,2-diylbis(oxy)) bis(3-nonylbenzenesulfonic acid) (9BA-2-9BA), 6,6'-(propane-1,3-diylbis(oxy)) bis(3-nonylbenzenesulfonic acid) (9BA-3-9BA), 6,6'-(butane-1,4-diylbis(oxy)) bis(3-nonylbenzenesulfonic acid) (9BA-4-9BA), and 6,6'-(hexane-1,6-diylbis(oxy)) bis(3-nonylbenzenesulfonic acid) (9BA-6-9BA), were synthesized and characterized by Fourier transform infrared (FTIR), (1)H NMR, elemental analysis, and melting temperature measurements. Their ability to lower the water surface tension and hexadecane/water interfacial tension was measured and correlated with the hydrophobicity and length of their alkyl spacer chain. Their aggregates in aqueous solutions were investigated using dynamic light scattering and transmission electron microscopy. Spherical vesicles could be found in aqueous solutions of four gemini surfactants with an apparent hydrodynamic radius (Rh) of approximately 100 nm. The critical micelle concentration (cmc) of four gemini surfactants evaluated by surface tension measurements was 1 order of magnitude smaller than that of conventional single-chain surfactant sodium dodecylsulfonate (SDS). And their C20, the gemini surfactant concentration required for lowering the surface tension of water by 20 mN/m, was about 2 orders of magnitude smaller than that of SDS, showing excellent efficiency at reducing the surface tension of water. In addition, the hexadecane/water interfacial tension could be less than 1.0 mN/m after using pure 9BA-m-9BA in water. Using 9BA-6-9BA the hexadecane/water interfacial tension was reduced to 0.21 mN/m.

Alterations in methylation and expression levels of imprinted genes H19 and Igf2 in the fetuses of diabetic mice.

The study aimed to reveal alterations in expression and methylation levels of the growth-related imprinted genes H19 and Igf2 in fetuses of diabetic mice. Diabetes was induced in female mice by intraperitoneal injection of streptozotocin. DNA and total RNA were extracted from fetuses obtained from diabetic and control dams on embryonic day (E) 14. Real-time RT-PCR analysis revealed that the mRNA expression of Igf2 in fetuses from diabetic mice was 0.65-fold of the control counterparts. Bisulfite genomic sequencing demonstrated that the methylation level of the H19-Igf2 imprint control region was 19.1% higher in diabetic fetuses than in those of control dams. In addition, the body weight of pups born to diabetic dams was 26.5% lower than that of the control group. The results indicate that maternal diabetes can affect fetal development by means of altered expression of imprinted genes. The modified genomic DNA methylation status of imprinting genes may account for the change in gene expression.

Exposure of preimplantation embryos to insulin alters expression of imprinted genes.

Insulin promotes early embryonic development, but whether this action affects postimplantation fetal development and alters the expression of imprinted genes remain to be determined. This study analyzed the expression and methylation levels of the growth-related imprinted genes H19 and insulin-like growth factor 2 (Igf2) in fetuses exposed to insulin before implantation. We cultured 2-cell embryos in either 0 or 0.25 microg/ml insulin until the blastocyst stage and then transferred them into pseudopregnant recipient mice. The number of embryos developing to blastocysts after insulin exposure was 16.4% higher than that of the control, and the birth body weight of the insulin-exposed group was 17.8% higher than that of the control group. Real-time reverse transcription-polymerase chain reaction analysis revealed that exposure of preimplantation embryos to insulin increased the mRNA expression of both Igf2 and H19 in embryonic day (E) 14 fetuses. Bisulfite genomic sequencing demonstrated that the methylation level of the H19-Igf2 imprint control region was 19.3% lower in insulin-exposed E14 fetuses than in controls. The present study indicates that insulin exposure during the preimplantation stage alters the expression of imprinted genes and affects fetal development.

[Effect of irradiation on tooth hard tissue and its resistance to acid].

OBJECTIVE: To study the effect of irradiation on the susceptibility of radiation caries. METHODS: The structures of 56 teeth enamel and dentin of 63 roots were observed using SEM and the collagen fibre and the resistance to the acid were also investigated after irradiation of 30 Gy, 50 Gy and 70 Gy. RESULTS: The enamel structure changes were found after irradiation with different doses. The significant difference was found in the enamel changes between high or middle dose group and low dose group or control. The dentin morphology changed, some collagen fibre vanished and resistance to acid was reduced after irradiation with 50 Gy and 70 Gy. CONCLUSIONS: The radiation reduced the resistance of teeth to the acid and increased the caries susceptibility.