Association of IFN‐γ polymorphisms with ankylosing spondylitis risk

The case‐control study was designed to investigate the genetic effects of interferon‐gamma (IFN‐γ) rs2069727 and rs1861494 polymorphisms on ankylosing spondylitis (AS) susceptibility in a Chinese Han population. Blood samples were collected from 108 AS patients and 110 healthy controls. IFN‐γ polymorphisms were genotyped by polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP). Hardy‐Weinberg equilibrium (HWE) test was performed in control group. Odds ratios (OR) with 95% confidence intervals (95% CI) were calculated using chi‐square test to evaluate the association between AS susceptibility and IFN‐γ polymorphisms, and the results were adjusted by logistic regressive analysis. The frequency of rs2069727 CC genotype was much higher in cases than that in controls, suggested its significant association with increased AS risk (adjusted OR = 5.899, 95% CI = 1.563‐22.261; P = .009). In addition, C allele also showed close association with increased risk of AS (adjusted OR = 2.052, 95% CI = 1.286‐1.704, P  = 0 .003). While the genotype and allele frequencies of IFN‐γ rs1861494 polymorphism were not significantly different between patients and controls (P  > 0.05 for all), IFN‐γ rs2069727 polymorphism is significantly associated with increased AS risk in a Chinese Han Population.     

The Flame‐Retardant Tris(1,3‐dichloro‐2‐propyl) Phosphate Represses Androgen Signaling in Human Prostate Cancer Cell Lines

The effects of six organophosphate flame retardants (OPFRs) tris(2‐butoxyethyl) phosphate, tris(2‐chloroethyl) phosphate, tris(1‐chloro‐2‐propyl) phosphate, tris(methylphenyl) phosphate, tris(1,3‐dichloro‐2‐propyl) phosphate (TDCIPP), and triethyl phosphate on the activities of androgen receptor (AR), estrogen receptor (ER), and aryl hydrocarbon receptor (AhR) were assessed in human prostate and endometrial cancer cells. OPFRs had no effect on ER or AhR target gene activation in ECC‐1 cells. The effect of TDCIPP on mRNA and protein accumulation of AR target genes was examined further. AR‐inducible gene and protein expression were significantly altered by TDCIPP exposure and repressed PSA levels in conditioned media of prostate cancer cells. We demonstrated that TDCIPP has no affinity for the AR ligand binding domain (AR‐LBD) and exerts its antiandrogenic effects in a noncompetitive fashion. Thus, the clinical relevance of TDCIPP exposure on prostate cancer detection and progression to a therapeutically refractile state ought to be investigated further.     

Alternation of extracellular matrix remodeling and apoptosis by activation of the aryl hydrocarbon receptor pathway in human periodontal ligament cells

It is well known that the aryl hydrocarbon receptor (AhR) is involved in the toxicity of halogenated aromatic hydrocarbons (HAH) and polycyclic aromatic hydrocarbons (PAH). Recent experiments have shown the induction of impaired tooth and hard‐tissue formation by AhR pathway activation, however, the effect on periodontal ligament (PDL) tissue remains unclear. Here, we investigated the effects of benzo(a)pyrene (BaP), a member of PAH, on the extracellular matrix (ECM) remodeling‐related molecules, collagen type I (COL‐I), matrix metalloproteinase‐1 (MMP‐1), alpha‐smooth muscle actin (α‐SMA) expression, and apoptosis in two different human periodontal ligament cells (HPDLCs). The transduction of AhR from the cytoplasm to the nucleus and the increase of AhR‐responsive genes; that is, cytochrome P450 1A1 (CYP1A1), cytochrome P450 1B1 (CYP1B1), and aryl‐hydrocarbon receptor repressor (AhRR), expression was induced by BaP exposure in both HPDLCs. BaP treatment significantly enhanced MMP‐1 mRNA expression and MMP‐1 protein production, while markedly suppressing COL‐I and a‐SMA mRNA expression in both HPDLCs. Furthermore, these BaP‐treated HPDLCs fell into apoptotic cell death as evidenced by induction in annexin V and caspase‐3/7 staining and reduction of total cell number and Bcl‐2 mRNA expression. Thus, BaP exposure altered the expression of ECM‐related molecules and induced apoptosis in HPDLCs through activation of the AhR pathway. Overactivity of the AhR pathway may induce an inappropriate turnover of PDL tissue via disordered ECM remodeling and apoptosis in PDL cells. J. Cell. Biochem. 113: 3093–3103, 2012. © 2012 Wiley Periodicals, Inc.     

ICAM‐1 and MKL‐1 polymorphisms impose considerable impacts on coronary heart disease occurrence

This study was aimed to explore the correlation of intercellular adhesion molecule‐1 (ICAM‐1) K469E and megakaryoblastic leukaemia factor‐1 (MKL‐1) ?184C/T polymorphisms with the susceptibility to coronary heart disease (CHD) in the Chinese Han population. 100 CHD patients and 91 healthy people that had no blood connection with each other were enrolled in this case‐control study. ICAM‐1 and MKL‐1 polymorphisms were genotyped by polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) approach. Multiple logistic regression was used to analyse the correlation between polymorphisms of ICAM‐1 and MKL‐1 and CHD susceptibility. Differences of genotype and allele frequencies of the two SNPs between case and control groups were analysed by chi‐square test. Odds ratios (ORs) and 95% confidence intervals (CIs) were indicated relative susceptibility of CHD. The distributions of ICAM‐1 and MKL‐1 polymorphisms in each group conformed to Hardy‐Weinberg equilibrium (HWE). After adjusting for traditional risk factors, the TT genotype frequency of MKL‐1 ?184C/T polymorphism was found significantly higher in case group than in control group (P < .05). Meanwhile, T allele frequency increased in case group compared with control group, and the differences had statistical significance (P = .04, OR = 2.34, 95% CI = 1.34‐5.26). Logistic regression analysis in this study proved that smoking, hypertension, diabetes and triglyceride (TG) were all risk factors for CHD ICAM‐1 K469E polymorphism has no association with the onset of CHD. But MKL‐1 ?184C/T polymorphism is associated with the risk of CHD and T allele might be a susceptibility factor for CHD.     

Androgen receptor variants and prostate cancer in humanized AR mice

Androgen, acting via the androgen receptor (AR), is central to male development, differentiation and hormone-dependent diseases such as prostate cancer. AR is actively involved in the initiation of prostate cancer, the transition to androgen independence, and many mechanisms of resistance to therapy. To examine genetic variation of AR in cancer, we created mice by germ-line gene targeting in which human AR sequence replaces that of the mouse. Since shorter length of a polymorphic N-terminal glutamine (Q) tract has been linked to prostate cancer risk, we introduced alleles with 12, 21 or 48 Qs to test this association. The three “humanized” AR mouse strains (h/mAR) are normal physiologically, as well as by cellular and molecular criteria, although slight differences are detected in AR target gene expression, correlating inversely with Q tract length. However, distinct allele-dependent differences in tumorigenesis are evident when these mice are crossed to a transgenic prostate cancer model. Remarkably, Q tract variation also differentially impacts disease progression following androgen depletion. This finding emphasizes the importance of AR function in androgen-independent as well as androgen-dependent disease. These mice provide a novel genetic paradigm in which to dissect opposing functions of AR in tumor suppression versus oncogenesis.     

Association between METTL3 gene polymorphisms and neuroblastoma susceptibility: A nine‐centre case‐control study

Neuroblastoma ranks as the most commonly seen and deadly solid tumour in infancy. The aberrant activity of m⁶A‐RNA methyltransferase METTL3 is involved in human cancers. Therefore, functional genetic variants in the METTL3 gene may contribute to neuroblastoma risk. In the current nine‐centre case‐control study, we aimed to analyse the association between the METTL3 gene single nucleotide polymorphisms (SNPs) and neuroblastoma susceptibility. We genotyped four METTL3 gene SNPs (rs1061026 T>G, rs1061027 C>A, rs1139130 A>G, and rs1263801 G>C) in 968 neuroblastoma patients and 1814 controls in China. We found significant associations between these SNPs and neuroblastoma risk in neither single‐locus nor combined analyses. Interestingly, in the stratified analysis, we observed a significant risk association with rs1061027 AA in subgroups of children ≤ 18 months of age (adjusted OR = 1.87, 95% CI = 1.03‐3.41, P = .040) and females (adjusted OR = 1.86, 95% CI = 1.07‐3.24, P = .028). Overall, we identified a significant association between METTL3 gene rs1061027 C>A polymorphism and neuroblastoma risk in children ≤18 months of age and females. Our findings provide novel insights into the genetic determinants of neuroblastoma.     

An ecological genetic delineation of local seed‐source provenance for ecological restoration

An increasingly important practical application of the analysis of spatial genetic structure within plant species is to help define the extent of local provenance seed collection zones that minimize negative impacts in ecological restoration programs. Here, we derive seed sourcing guidelines from a novel range‐wide assessment of spatial genetic structure of 24 populations of Banksia menziesii (Proteaceae), a widely distributed Western Australian tree of significance in local ecological restoration programs. An analysis of molecular variance (AMOVA) of 100 amplified fragment length polymorphism (AFLP) markers revealed significant genetic differentiation among populations (Φ_PT = 0.18). Pairwise population genetic dissimilarity was correlated with geographic distance, but not environmental distance derived from 15 climate variables, suggesting overall neutrality of these markers with regard to these climate variables. Nevertheless, Bayesian outlier analysis identified four markers potentially under selection, although these were not correlated with the climate variables. We calculated a global R‐statistic using analysis of similarities (ANOSIM) to test the statistical significance of population differentiation and to infer a threshold seed collection zone distance of ~60 km (all markers) and 100 km (outlier markers) when genetic distance was regressed against geographic distance. Population pairs separated by >60 km were, on average, twice as likely to be significantly genetically differentiated than population pairs separated by <60 km, suggesting that habitat‐matched sites within a 30‐km radius around a restoration site genetically defines a local provenance seed collection zone for B. menziesii. Our approach is a novel probability‐based practical solution for the delineation of a local seed collection zone to minimize negative genetic impacts in ecological restoration.     

Anti‐HSV‐1 and HSV‐2 Flavonoids and a New Kaempferol Triglycoside from the Medicinal Plant Kalanchoe daigremontiana

Kalanchoe daigremontiana (Crassulaceae) is a medicinal plant native to Madagascar. The aim of this study was to investigate the flavonoid content of an aqueous leaf extract from K. daigremontiana (Kd), and assess its antiherpetic potential. The major flavonoid, kaempferol 3‐O‐β‐d ‐xylopyranosyl‐(1 → 2)‐α‐l ‐rhamnopyranoside ( 1 ), was isolated from the AcOEt fraction (Kd‐AC). The BuOH‐soluble fraction afforded quercetin 3‐O‐β‐d ‐xylopyranosyl‐(1 → 2)‐α‐l ‐rhamnopyranoside ( 2 ) and the new kaempferol 3‐O‐β‐d ‐xylopyranosyl‐(1 → 2)‐α‐l ‐rhamnopyranoside‐7‐O‐β‐d ‐glucopyranoside ( 3 ), named daigremontrioside. The crude extract, Kd‐AC fraction, flavonoids 1 and 2 were evaluated using acyclovir‐sensitive strains of HSV‐1 and HSV‐2. Kd‐AC was highly active against HSV‐1 (EC₅₀ = 0.97 μg/ml, SI > 206.1) and HSV‐2 (EC₅₀ = 0.72 μg/ml, SI > 277.7). Flavonoids 1 and 2 showed anti‐HSV‐1 (EC₅₀ = 7.4 μg/ml; SI > 27 and EC₅₀ = 5.8 μg/ml; SI > 8.6, respectively) and anti‐HSV‐2 (EC₅₀ = 9.0 μg/ml; SI > 22.2 and EC₅₀ = 36.2 μg/ml; SI > 5.5, respectively) activities, suggesting the contribution of additional substances to the antiviral activity.     

A Survey Investigating the Infection of Fusarium langsethiae and Production of HT‐2 and T‐2 Mycotoxins in UK Oat Fields

Fusarium langsethiae is a toxigenic fungal species that has been reported in European small‐grain cereal crops such as oats, wheat and barley. Although its relative contribution to fusarium head blight (FHB) symptoms is not well understood, it is reported to contaminate these cereals with high levels of HT‐2 and T‐2 trichothecenes mycotoxins that are currently under consideration for legislation by the European Commission. Ten commercial oat fields in Shropshire and Staffordshire (two adjacent counties in the Midlands) in the UK were surveyed in the 2006/2007 growing season. Samples were taken from predetermined field locations at Zadoks growth stages 32/33, 69, 77‐85 and 90‐92 for F. langsethiae biomass and HT‐2 and T‐2 toxins quantification. The results from this study showed that oats can be heavily infected with F. langsethiae and have high concentrations of HT‐2 and T‐2 toxins with no apparent FHB symptoms. The regression of HT‐2 + T‐2 toxins on F. langsethiae DNA concentration was highly significant (P < 0.001, r² = 0.55). The results indicated that although F. langsethiae had no direct effect on crop yield, it may result in indirect economic losses where the grain can be rejected or downgraded as a result of intolerable levels of HT‐2 and T‐2 toxins, which are of human food and animal feed safety concern. The influence of cultural field practices on the infection and HT‐2 and T‐2 toxins accumulation in oats was not clear and warrants further studies to identify the sources of F. langsethiae inoculum and conditions favourable for infection and mycotoxin production.     

Inhibition of autophagy enhances the effects of the AKT inhibitor MK‐2206 when combined with paclitaxel and carboplatin in BRAF wild‐type melanoma

This study investigates the mechanism of action behind the long‐term responses (12–16 months) of two BRAF WT melanoma patients to the AKT inhibitor MK‐2206 in combination with paclitaxel and carboplatin. Although single agent MK‐2206 inhibited phospho‐AKT signaling, it did not impact in vitro melanoma growth or survival. The combination of MK‐2206 with paclitaxel and carboplatin was cytotoxic in long‐term colony formation and 3D spheroid assays, and induced autophagy. Autophagy was initially protective with autophagy inhibitors and deletion of ATG5 found to enhance cytotoxicity. Although prolonged autophagy induction (>6 days) led to caspase‐dependent apoptosis, drug resistant clones still emerged. Autophagy inhibition enhanced the cell death response through reactive oxygen species and could be reversed by anti‐oxidants. We demonstrate for the first time that AKT inhibition in combination with chemotherapy may have clinical activity in BRAF WT melanoma and show that an autophagy inhibitor may prevent resistance to these drugs.     

Fitness of Bt‐resistant cabbage loopers on Bt cotton plants

Development of resistance to the insecticidal toxins from Bacillus thuringiensis (Bt) in insects is the major threat to the continued success of transgenic Bt crops in agriculture. The fitness of Bt‐resistant insects on Bt and non‐Bt plants is a key parameter that determines the development of Bt resistance in insect populations. In this study, a comprehensive analysis of the fitness of Bt‐resistant Trichoplusia ni strains on Bt cotton leaves was conducted. The Bt‐resistant T. ni strains carried two genetically independent mechanisms of resistance to Bt toxins Cry1Ac and Cry2Ab. The effects of the two resistance mechanisms, individually and in combination, on the fitness of the T. ni strains on conventional non‐Bt cotton and on transgenic Bt cotton leaves expressing a single‐toxin Cry1Ac (Bollgard I) or two Bt toxins Cry1Ac and Cry2Ab (Bollgard II) were examined. The presence of Bt toxins in plants reduced the fitness of resistant insects, indicated by decreased net reproductive rate (R₀) and intrinsic rate of increase (r). The reduction in fitness in resistant T. ni on Bollgard II leaves was greater than that on Bollgard I leaves. A 12.4‐day asynchrony of adult emergence between the susceptible T. ni grown on non‐Bt cotton leaves and the dual‐toxin‐resistant T. ni on Bollgard II leaves was observed. Therefore, multitoxin Bt plants not only reduce the probability for T. ni to develop resistance but also strongly reduce the fitness of resistant insects feeding on the plants.     

Sequence capture using AFLP‐generated baits: A cost‐effective method for high‐throughput phylogenetic and phylogeographic analysis

Target sequence capture is an efficient technique to enrich specific genomic regions for high‐throughput sequencing in ecological and evolutionary studies. In recent years, many sequence capture approaches have been proposed, but most of them rely on commercial synthetic baits which make the experiment expensive. Here, we present a novel sequence capture approach called AFLP‐based genome sequence capture (AFLP Capture). This method uses the AFLP (amplified fragment length polymorphism) technique to generate homemade capture baits without the need for prior genome information, thus is applicable to any organisms. In this approach, biotinylated AFLP fragments representing a random fraction of the genome are used as baits to capture the homologous fragments from genomic shotgun sequencing libraries. In a trial study, by using AFLP Capture, we successfully obtained 511 orthologous loci (>700,000 bp in total length) from 11 Odorrana species and more than 100,000 single nucleotide polymorphisms (SNPs) in four analyzed individuals of an Odorrana species. This result shows that our method can be used to address questions of various evolutionary depths (from interspecies level to intraspecies level). We also discuss the flexibility in bait preparation and how the sequencing data are analyzed. In summary, AFLP Capture is a rapid and flexible tool and can significantly reduce the experimental cost for phylogenetic studies that require analyzing genome‐scale data (hundreds or thousands of loci).     

LIN28A gene polymorphisms modify neuroblastoma susceptibility: A four‐centre case‐control study

Neuroblastoma ranks the most common seen solid tumour in childhood. Overexpression of LIN28A gene has been linked to the development of multiple human malignancies, but the relationship between LIN28A single nucleotide polymorphisms (SNPs) and neuroblastoma susceptibility is still under debate. Herein, we evaluated the correlation of four potentially functional LIN28A SNPs (rs3811464 G>A, rs3811463 T>C, rs34787247 G>A, and rs11247957 G>A) and neuroblastoma susceptibility in 505 neuroblastoma patients and 1070 controls from four independent hospitals in China. The correlation strengths were determined by using odds ratios (ORs) and corresponding 95% confidence intervals (CIs). Among these SNPs, rs34787247 G>A exhibited a significant association with increased susceptibility in neuroblastoma (GA vs GG: adjusted OR = 1.30, 95% CI = 1.03‐1.64; AA vs GG: adjusted OR = 2.51, 95% CI = 1.36‐4.64, AA/GA vs GG: adjusted OR = 1.42, 95% CI = 1.12‐1.80, AA vs GG/GA: adjusted OR = 2.39, 95% CI = 1.29‐4.42). Furthermore, the combined analysis of risk genotypes revealed that subjects carrying three risk genotypes (adjusted OR = 1.64, 95% CI = 1.02‐2.63) are more inclined to develop neuroblastoma than those without risk genotype, and so do carriers of 1‐4 risk genotypes (adjusted OR = 1.26, 95% CI = 1.01‐1.56). Stratification analysis further revealed risk effect of rs3811464 G>A, rs34787247 G>A and 1‐4 risk genotypes in some subgroups. Haplotype analysis of these four SNPs yields two haplotypes significantly correlated with increased neuroblastoma susceptibility. Overall, our finding indicated that LIN28A SNPs, especially rs34787247 G>A, may increase neuroblastoma risk.     

Colony‐age‐dependent variation in cuticular hydrocarbon profiles in subterranean termite colonies

Cuticular hydrocarbons (CHCs) have, in insects, important physiological and ecological functions, such as protection against desiccation and as semiochemicals in social taxa, including termites. CHCs are, in termites, known to vary qualitatively and/or quantitatively among species, populations, castes, or seasons. Changes to hydrocarbon profile composition have been linked to varying degrees of aggression between termite colonies, although the variability of results among studies suggests that additional factors might have been involved. One source of such variability may be colony age, as termite colony demographics significantly change over time, with different caste and instar compositions throughout the life of the colony. We here hypothesize that the intracolonial chemical profile heterogeneity would be high in incipient termite colonies but would homogenize over time as a colony ages and accumulates older workers in improved homeostatic conditions. We studied caste‐specific patterns of CHC profiles in Coptotermes gestroi colonies of four different age classes (6, 18, 30, and 42 months). The CHC profiles were variable among castes in the youngest colonies, but progressively converged toward a colony‐wide homogenized chemical profile. Young colonies had a less‐defined CHC identity, which implies a potentially high acceptance threshold for non‐nestmates conspecifics in young colonies. Our results also suggest that there was no selective pressure for an early‐defined colony CHC profile to evolve in termites, potentially allowing an incipient colony to merge nonagonistically with another conspecific incipient colony, with both colonies indirectly and passively avoiding mutual destruction as a result.