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Global DNA hypomethylation is commonly observed in benzene-exposed workers, but the underlying mechanisms remain unclear. We sought to discover the relationships among reduced white blood cell (WBC) counts, micronuclear (MN) frequency, and global DNA methylation to determine whether there were associations with mutations in DNMT3A/3B. Therefore, we recruited 410 shoe factory workers and 102 controls from Wenzhou in Zhenjiang Province. A Methylated DNA Quantification Kit was used to quantify global DNA methylation, and single nucleotide polymorphisms (SNPs) in DNMT3A (rs36012910, rs1550117, and R882) and DNMT3B (rs1569686, rs2424909, and rs2424913) were identified using the restriction fragment length polymorphism method. A multilinear regression analysis demonstrated that the benzene-exposed workers experienced significant global DNA hypomethylation compared with the controls (β = -0.51, 95% CI: -0.69 to -0.32, P < 0.001). The DNMT3A R882 mutant allele (R882H and R882C) (β = -0.25, 95% CI: -0.54 to 0.04, P = 0.094) and the DNMT3B rs2424909 GG allele (β = -0.37, 95% CI: -0.70 to -0.03, P = 0.031) were significantly associated with global DNA hypomethylation compared with the wild-type genotype after adjusting for confounding factors. Furthermore, the MN frequency in the R882 mutant allele (R882H and R882C) (FR = 1.18, 95% CI: 0.99 to 1.40, P = 0.054) was higher than that of the wild-type. The results imply that hypomethylation occurs due to benzene exposure and that mutations in DNMTs are significantly associated with global DNA methylation, which might have influenced the induction of MN following exposure to benzene. Environ. Mol. Mutagen. 58:678-687, 2017. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

Parkinson's disease is a common neurodegenerative disease in the elderly, and mitochondrial defects underlie the pathogenesis of PD. Impairment of mitochondrial homeostasis results in reactive oxygen species formation, which in turn can potentiate the accumulation of dysfunctional mitochondria, forming a vicious cycle in the neuron. Mitochondrial fission/fusion and biogenesis play important roles in maintaining mitochondrial homeostasis. It has been reported that PGC-1α is a powerful transcription factor that is widely involved in the regulation of mitochondrial biogenesis, oxidative stress, and other processes. Therefore, we explored mitochondrial biogenesis, mitochondrial fission/fusion, and especially PGC-1α as the key point in the signaling mechanism of their interaction in rotenone-induced dopamine neurotoxicity. The results showed that mitochondrial number and mass were reduced significantly, accompanied by alterations in proteins known to regulate mitochondrial fission/fusion (MFN2, OPA1, Drp1, and Fis1) and mitochondrial biogenesis (PGC-1α and mtTFA). Further experiments proved that inhibition of mitochondrial fission or promotion of mitochondrial fusion has protective effects in rotenone-induced neurotoxicity and also promotes mitochondrial biogenesis. By establishing cell models of PGC-1α overexpression and reduced expression, we found that PGC-1α can regulate MFN2 and Drp1 protein expression and phosphorylation to influence mitochondrial fission/fusion. In summary, it can be concluded that PGC-1α-mediated cross talk between mitochondrial biogenesis and fission/fusion contributes to rotenone-induced dopaminergic neurodegeneration.

Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental pollutants that have adverse effects on the male reproductive function. Many studies have confirmed that PAHs preferentially accumulate in mitochondria DNA relative to nuclear DNA and disrupt mitochondrial functions. However, it is rare whether exposure to PAHs is associated with mitochondrial damage and dysfunction in sperm. To evaluate the effects of PAHs on sperm mitochondria, we measured mitochondrial membrane potential (MMP), mitochondrial DNA copy number (mtDNAcn) and mtDNA integrity in 666 individuals from the Male Reproductive Health in Chongqing College Students (MARHCS) study. PAHs exposure was estimated by measuring eight urinary PAH metabolites (1-OHNap, 2-OHNap, 1-OHPhe, 2-OHPhe, 3-OHPhe, 4-OHPhe, 2-OHFlu and 1-OHPyr). The subjects were divided into low, median and high exposure groups using the tertile levels of urinary PAH metabolites. In univariate analyses, the results showed that increased levels of 2-OHPhe, 3-OHPhe, ∑Phe metabolites and 2-OHFlu were found to be associated with decreased sperm mtDNAcn. After adjusting for potential confounders, significantly negative associations of these metabolites remained (p = 0.039, 0.012, 0.01, 0.035, respectively). Each 1 μg/g creatinine increase in 2-OHPhe, 3-OHPhe, ∑Phe metabolites and 2-OHFlu was associated with a decrease in sperm mtDNAcn of 9.427%, 11.488%, 9.635% and 11.692%, respectively. There were no significant associations between urinary PAH metabolites and sperm MMP or mtDNA integrity. The results indicated that the low exposure levels of PAHs can cause abnormities in sperm mitochondria., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Objectives: Electrospun cotton wool-like nanocomposite (ECWN) is a novel synthetic bone substitute that incorporates amorphous calcium phosphate nanoparticles into a biodegradable synthetic copolymer poly(lactide-co-glycolide). The objectives of this study were to develop a tooth extraction socket model in sheep for bone graft research and to compare ECWN and bovine-derived xenograft (BX) in this model., Material and Methods: Sixteen cross-bred female sheep were used. Bilateral mandibular premolars were extracted atraumatically. Second and third premolar sockets were filled (Latin-square allocation) with BX, ECWN or left unfilled. Resorbable collagen membranes were placed over BX and selected ECWN grafted sockets. Eight sheep per time period were sacrificed after 8 and 16 weeks. Resin-embedded undemineralised sections were analysed for descriptive histology and histomorphometric analyses., Results: At 8 weeks, there were with no distinct differences in healing among the different sites. At 16 weeks, osseous healing followed a fine trabecular pattern in ECWN sites. Non-grafted sites showed thick trabeculae separated by large areas of fibrovascular connective tissue. In BX grafted sites, xenograft particles were surrounded by newly formed bone or fibrovascular connective tissue. There were no statistically significant differences in bone formation across the four groups. However, ECWN sites had significantly less residual graft material than BX sites at 16 weeks (P = 0.048)., Conclusions: This first description of a tooth extraction socket model in sheep supports the utility of this model for bone graft research. The results of this study suggested that the novel material ECWN did not impede bone ingrowth into sockets and showed evidence of material resorption., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Study Question: Is anogenital distance associated with semen parameters and serum reproductive hormone levels in males?, Summary Answer: Anogenital distance is associated with serum reproductive hormones, but not with semen quality., What Is Known Already: Epidemiological studies have suggested that anogenital distance (AGD) may be associated with testicular dysfunction in adult men. However, the role of AGD in estimating male reproductive function remains unclear., Study Design, Size, Duration: We examined the associations between AGD and semen parameters and reproductive hormones levels in 656 young college students in a Male Reproductive Health in Chongqing College Students (MARHCSs) cohort study in June of 2014., Participants/materials, Setting, Methods: In this study, two variants of AGD (AGDAP and AGDAS) were measured in 656 university students. Serum levels of testosterone (T), estradiol (E2), progesterone (P), prolactin (PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), sex hormone-binding globulin (SHBG) and inhibin-B; and semen quality outcomes, including semen volume, sperm concentration, total sperm number, sperm progressive motility, total motility and morphology, were assessed. The associations between AGD and semen parameters/reproductive hormones levels were analyzed using multiple regression analysis., Main Results and the Role of Chance: Both AGDAS and AGDAP were not associated with any semen parameters. In the non-parametric correlation analysis, AGDAP were correlated with sperm progressive motility and reproductive hormones of E2, testosterone, SHBG and the testosterone/LH ratio. However, body mass index (BMI) also significantly correlated with serum testosterone ( ITALIC! r = -0.216, ITALIC! P = <0.0001) and SHBG ( ITALIC! r = -0.229, ITALIC! P = <0.001). In the multiple regression models, AGDAP was negatively associated with the serum E2 level (95% CI, -0.198 to -0.043; ITALIC! P = 0.002) and positively associated with the ratio of T/E2 (95% CI, 0.004-0.011; ITALIC! P = 0.001) after an adjustment for BMI and other confounders., Limitations, Reasons for Caution: Using only a single semen sample to predict male reproductive function over a longer period is a potential limitation of the present study. The other limitation is the cross-sectional nature of the study design. Longitudinal data from an extended follow-up on a large cohort would be more definitive., Wider Implications of the Findings: Our results do not support previous studies where AGD is associated with male semen quality. The utility of AGD in predicting reproductive outcomes in adult males should thus be considered prudently., Study Funding/competing Interests: This study was supported by the Key Program of Natural Science Funding of China (no. 81130051), Young Scientist Program of NSFC (no. 81502788) and the National Scientific and Technological Support Program of China (no. 2013BAI12B02). None of authors had any competing interests to declare., (© The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The soybean cyst nematode (SCN; Heterodera glycines) induces the formation of a multinucleated feeding site, or syncytium, whose etiology includes massive gene expression changes. Nevertheless, the genetic networks underlying gene expression control in the syncytium are poorly understood. DNA methylation is a critical epigenetic mark that plays a key role in regulating gene expression. To determine the extent to which DNA methylation is altered in soybean (Glycine max) roots during the susceptible interaction with SCN, we generated whole-genome cytosine methylation maps at single-nucleotide resolution. The methylome analysis revealed that SCN induces hypomethylation to a much higher extent than hypermethylation. We identified 2,465 differentially hypermethylated regions and 4,692 hypomethylated regions in the infected roots compared with the noninfected control. In addition, 703 and 1,346 unique genes were identified as overlapping with hyper- or hypomethylated regions, respectively. The differential methylation in genes apparently occurs independently of gene size and GC content but exhibits strong preference for recently duplicated paralogs. Furthermore, a set of 278 genes was identified as specifically syncytium differentially methylated genes. Of these, we found genes associated with epigenetic regulation, phytohormone signaling, cell wall architecture, signal transduction, and ubiquitination. This study provides, to our knowledge, new evidence that differential methylation is part of the regulatory mechanisms controlling gene expression changes in the nematode-induced syncytium., (© 2015 American Society of Plant Biologists. All Rights Reserved.)

Ovarian cancer is one of the most common types of cancer in females and is the leading cause of death among gynaecological cancers in women worldwide. In the present study, we identified insulin-like growth factor 2 (IGF2) as a differentially expressed gene between cancerous and non-cancerous ovarian tissues. IGF2 was frequently increased in the human ovarian cancers when compared to the frequency in the non-cancerous ovarian tissues both at the mRNA (30/35) and protein level (61/72). The mean level of IGF2 in the tumor tissues was markedly higher than that in the non-cancerous tissues (nearly 3-fold change) (P=0.000). There was a significant correlation of IGF2 expression with histological grade (P=0.047). Kaplan-Meier analysis indicated that the ovarian cancer patients with high IGF2 expression showed a poorer prognosis both in regards to overall survival (OS) and progression-free survival (PFS) (n=1,648, P=0.000). Further analysis revealed that high expression of IGF2 was an unfavorable factor for the prognosis of the ovarian cancer patients at clinical stage I + II, stage III, histological grade 2, grade 3 or those treated with chemotherapy containing platin and Taxol. Our data provide evidence that IGF2 expression is frequently increased in ovarian cancer tissues, and high expression of IGF2 may be a significant prognostic factor for poor survival in ovarian cancer patients.

The protein kinase (PK) gene family is one of the largest and most highly conserved gene families in plants and plays a role in nearly all biological functions. While a large number of genes have been predicted to encode PKs in soybean, a comprehensive functional classification and global analysis of expression patterns of this large gene family is lacking. In this study, we identified the entire soybean PK repertoire or kinome, which comprised 2166 putative PK genes, representing 4.67% of all soybean protein-coding genes. The soybean kinome was classified into 19 groups, 81 families, and 122 subfamilies. The receptor-like kinase (RLK) group was remarkably large, containing 1418 genes. Collinearity analysis indicated that whole-genome segmental duplication events may have played a key role in the expansion of the soybean kinome, whereas tandem duplications might have contributed to the expansion of specific subfamilies. Gene structure, subcellular localization prediction, and gene expression patterns indicated extensive functional divergence of PK subfamilies. Global gene expression analysis of soybean PK subfamilies revealed tissue- and stress-specific expression patterns, implying regulatory functions over a wide range of developmental and physiological processes. In addition, tissue and stress co-expression network analysis uncovered specific subfamilies with narrow or wide interconnected relationships, indicative of their association with particular or broad signalling pathways, respectively. Taken together, our analyses provide a foundation for further functional studies to reveal the biological and molecular functions of PKs in soybean., (© The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.)

The Rho GDP dissociation inhibitor (RhoGDI) can bind to small GTPases and keep them in a biologically inactive state in cytoplasm, through which it affects actin polymerization and cell motility. However, mechanisms underlying how RhoGDI regulates Rho GTPase complex formation/membrane extraction/GTPase dissociation remain largely unexplored. Our previous studies reported that X-linked inhibitor of apoptosis protein (XIAP) interacted with RhoGDI via its RING domain and negatively modulated RhoGDI SUMOylation and HCT116 cancer cell migration. Here, we identified that RhoGDI SUMOylation specifically occurred at Lys-138, which was inhibited by XIAP domain. We further demonstrated that RhoGDI SUMOylation at Lys-138 was crucial for inhibiting actin polymerization and cytoskeleton formation as well as cancer cell motility. Moreover, SUMO-RhoGDI had a much higher binding affinity to small Rho GTPase compared with the un-SUMOylated form of RhoGDI. Taken together, our study demonstrated a novel modification of RhoGDI, SUMOylation at Lys-138, which played a key role in regulating Rho GTPase activation in cancer cells. The physiological regulation of RhoGDI SUMOylation by the RING domain of XIAP may account for modulation of cancer cell invasion and metastasis by XIAP.

X-linked inhibitor of apoptosis protein (XIAP) overexpression has been found to be associated with malignant cancer progression and aggression in individuals with many types of cancers. However, the molecular basis of XIAP in the regulation of cancer cell biological behavior remains largely unknown. In this study, we found that a deficiency of XIAP expression in human cancer cells by either knock-out or knockdown leads to a marked reduction in β-actin polymerization and cytoskeleton formation. Consistently, cell migration and invasion were also decreased in XIAP-deficient cells compared with parental wild-type cells. Subsequent studies demonstrated that the regulation of cell motility by XIAP depends on its interaction with the Rho GDP dissociation inhibitor (RhoGDI) via the XIAP RING domain. Furthermore, XIAP was found to negatively regulate RhoGDI SUMOylation, which might affect its activity in controlling cell motility. Collectively, our studies provide novel insights into the molecular mechanisms by which XIAP regulates cancer invasion and offer a further theoretical basis for setting XIAP as a potential prognostic marker and specific target for treatment of cancers with metastatic properties.

Background: Polycyclic aromatic hydrocarbons (PAHs), a class of the most ubiquitous environmental contaminants, may reduce male reproductive functions, but the data from human population studies are very limited., Objectives: We designed this study to determine whether environmental exposure to PAHs contributes to the alteration in semen quality, sperm DNA damage, and apoptosis in the general male human population., Methods: We measured urinary levels of four PAH metabolites and assessed semen quality, sperm apoptotic markers with Annexin V assay, and sperm DNA damage with comet assay in 232 men from Chongqing, China., Results: We found that increased urinary 2-hydroxynaphthalene (2-OHNa) levels were associated with increased comet parameters, including the percentage of DNA in the tail (tail%) [β coefficient = 13.26% per log unit 2-OHNa (micrograms per gram creatinine); 95% confidence interval (CI), 7.97-18.55]; tail length (12.25; 95% CI, 0.01-24.52), and tail distribution (7.55; 95% CI, 1.28-18.83). The urinary level of 1-hydroxypyrene was associated only with increased tail% (5.32; 95% CI, 0.47-10.17). Additionally, the increased levels of four urinary PAH metabolites were significantly associated with decreased vital Annexin V negative sperm counts. However, there was no significant association between urinary PAH metabolite levels and human semen parameters or morphology of the sperm samples., Conclusions: Our data indicate that the environmental level of PAH exposure is associated with increased sperm DNA damage but not with semen quality. These findings suggest that exposure to PAHs may disrupt sperm DNA and thereby interfere with human male fertility.

p27 is an atypical tumor suppressor that can regulate the activity of cyclin-dependent kinases and G(0)-to-S phase transitions. More recent studies reveal that p27 may also exhibit its tumor-suppressive function through regulating many other essential cellular events. However, the molecular mechanisms underlying these anticancer effects of p27 are largely unknown. In this study, we found that depletion of p27 expression by either gene knock-out or knockdown approaches resulted in up-regulation of both Hsp27 and Hsp70 expression at mRNA- and promoter-derived transcription as well as protein levels upon arsenite exposure, indicating that p27 provides a negative signal for regulating the expression of Hsp27 and Hsp70. Consistently, arsenite-induced activation of JNK2/c-Jun and HSF-1 pathways was also markedly elevated in p27 knock-out (p27(-/-)) and knockdown (p27 shRNA) cells. Moreover, interference with the expression or function of JNK2, c-Jun, and HSF-1, but not JNK1, led to dramatic inhibition of arsenite-induced Hsp27 and Hsp70 expression. Collectively, our results demonstrate that p27 suppresses Hsp27 and Hsp70 expression at the transcriptional level specifically through JNK2/c-Jun- and HSF-1-dependent pathways upon arsenite exposure, which provides additional important molecular mechanisms for the tumor-suppressive function of p27.

Objective: To take Cuntan (Yangtze River) and Daxigou (Jialing River) as the representative, in order to study the cytochrome P450 1A1 (CYP1A1) gene expression in H4IIE cell treated with the organic pollutants in Chongqing source water between 2004 and 2005., Methods: The organic pollutants were extracted with solid phase extraction, dissolved the organic pollutants in dimethyl sulphoxide (DMSO) . The H4IIE cell was treated with the extracts. The differences of CYP1A1 mRNA expression among different treatment groups were detected by reverse transcriptase-polymerase chain reaction (RT-PCR). The activities of CYP1A1 promotor were deteceted by electrophoretic mobility shift assay (EMSA). Results CYP1A1 mRNA expressions in H4IIE cells were observed in all the groups at the time of 12h and 24h, as well as in the 2005.01 Daxigon and 2005.01 Cuntan treated groups at the time of 48h, hut were not observed in all the groups at the time of 72h. The aryl hydrocarbon receptor-aryl hydrocarbon receptor nuclear translocator (AhR-ARNT) heterdimers were observed in all groups at the time of 24h., Conclusion: All samples could induce the activity of the CYP1A1 gene promoter XRE, and could induce the expression of CYP1A1 mRNA, hut the quantities of CYP1A1 mRNA expression were different according to the different treating time.

p53, one of the most commonly mutated genes in human cancers, is thought to be associated with cancer development. Hence, screening and identifying natural or synthetic compounds with anti-cancer activity via p53-independent pathway is one of the most challenging tasks for scientists in this field. Compound JKA97 (methoxy-1-styryl-9H-pyrid-[3,4-b]-indole) is a small molecule synthetic anti-cancer agent, with unknown mechanism(s). In this study we have demonstrated that the anti-cancer activity of JKA97 is associated with apoptotic induction via p53-independent mechanisms. We found that co-incubation of human colon cancer HCT116 cells with JKA97 inhibited HCT116 cell anchorage-independent growth in vitro and tumorigenicity in nude mice and also induced a cell apoptotic response, both in the cell culture model and in a tumorigenesis nude mouse model. Further studies showed that JKA97-induced apoptosis was dramatically impaired in Bax knock-out (Bax(-/-)) HCT116 cells, whereas the knock-out of p53 or PUMA did not show any inhibitory effects. The p53-independent apoptotic induction by JKA97 was confirmed in other colon cancer and hepatocarcinoma cell lines. In addition, our results showed an induction of Bax translocation and cytochrome c release from the mitochondria to the cytosol in HCT116 cells, demonstrating that the compound induces apoptosis through a Bax-initiated mitochondria-dependent pathway. These studies provide a molecular basis for the therapeutic application of JKA97 against human cancers with p53 mutations.

Objective: To investigate the effects of hydroxylammonium nitrate (HAN) on the blood system in rats., Methods: A total of 160 rats were randomly divided into three HAN treated groups and one negative control group, each group included 40 rats. Different doses of HAN at 6.97, 13.93 and 27.86mg/kg were administered to the three treated groups by intraperitoneal injection, and the control group was treated with 0.9% saline, the treatment had been performed every other day for 13 weeks. After the last treatment, 30 rats of each group were sacrificed and the rest were kept for another 4 weeks for recovery. Hematological parameters, reticulocyte and marrow cells were observed and measured., Results: For hematological parameters, the main changes were the decrease of RBC and HGB level and the increase of WBC at the end of the administration (P < 0.05). The reticulocyte values were obviously increase along with the increasing HAN dosage compared with those of control group (P < 0.01). For bone marrow cells observation, the ratio of erythrocytic line increased, and the ratio of granulocytes/erythrocyte was lower than that of control group (P < 0.05). After 4 weeks' recovery period, no obviously changes were observed for hematological parameters, reticulocyte and marrow cells., Conclusion: HAN has toxic effect on the blood system in rats for long-term exposure.

Fossils of the giant panda Ailuropoda (Order Carnivora, Family Ursidae) are largely isolated teeth, mandibles, and a few rare skulls, known from the late Pliocene to late Pleistocene in China and Southeast Asia. Much of this material represents a Pleistocene chronospecies, Ailuropoda baconi, an animal larger than the living giant panda, Ailuropoda melanoleuca. The earliest certain record of Ailuropoda is the late Pliocene chronospecies, Ailuropoda microta, smaller than either A. baconi or A. melanoleuca, and previously known only from teeth and a few mandibles from karst caves in south China. Here, we report the discovery of the first skull of A. microta, establishing its cranial anatomy and demonstrating that the specialized cranial and dental adaptations of Ailuropoda for durophagous feeding behavior centered on bamboo were already evident in this late Pliocene species. The skull from Jinyin cave (Guangxi) and dental remains from other karst localities in southeastern China show that Ailuropoda microta occupied south China from approximately 2 to 2.4 Myr ago after a marked global climatic deterioration. Dental and basicranial anatomy indicate a less specialized morphology early in the history of the lineage and support derivation of the giant panda from the Miocene Asian ursid Ailurarctos.