Per- and polyfluoroalkyl substances inhibit human and rat 17β-hydroxysteroid dehydrogenase 1: Quantitative structure-activity relationship and molecular docking analysis

Per- and polyfluoroalkyl (PFAS) substances are enduring industrial materials. 17β-Hydroxysteroid dehydrogenase isoform 1 (17β-HSD1) is an estrogen metabolizing enzyme, which transforms estrone into estradiol in human placenta and rat ovary. Whether PFAS inhibit 17β-HSD1 and what the structure-activity relationship (SAR) remains unexplored. We screened 18 PFAS for inhibiting human and rat 17β-HSD1 in microsomes and studied their SAR and mode of action(MOA). Of the 11 perfluorocarboxylic acids (PFCAs), C8-C14 PFCAs at a concentration of 100 μM substantially inhibited human 17β-HSD1, with order of C11 (half-maximal inhibition concentration, IC50, 8.94 μM) > C10 (10.52 μM) > C12 (14.90 μM) > C13 (30.97 μM) > C9 (43.20 μM) > C14 (44.83 μM) > C8 (73.38 μM) > others. Of the 7 per- and poly-fluorosulfonic acids (PFSAs), the potency was C8S (IC50, 14.93 μM) > C7S (80.70 μM) > C6S (177.80 μM) > others. Of the PFCAs, C8-C14 PFCAs at 100 μM markedly reduced rat 17β-HSD1 activity, with order of C11 (IC50, 9.11 μM) > C12 (14.30 μM) > C10 (18.24 μM) > C13 (25.61 μM) > C9 (67.96 μM) > C8 (204.39 μM) > others. Of the PFSAs, the potency was C8S (IC50, 37.19 μM) > C7S (49.38 μM) > others. In contrast to PFOS (C6S), the partially fluorinated compound 6:2 FTS with an equivalent number of carbon atoms demonstrated no inhibition of human and rat 17β-HSD1 activity at a concentration of 100 μM. The inhibition of human and rat enzymes by PFAS followed a V-shaped trend from C4 to C14, with a nadir at C11. Moreover, human 17β-HSD1 was more sensitive than rat enzyme. PFAS inhibited human and rat 17β-HSD1 in a mixed mode. Docking analysis revealed that they bind to the NADPH and steroid binding site of both 17β-HSD1 enzymes. The 3D quantitative SAR (3D-QSAR) showed that hydrophobic region, hydrogen bond acceptor and donor are key factors in binding to 17β-HSD1 active sites. In conclusion, PFAS exhibit inhibitory effects on human and rat 17β-HSD1 depending on factors such as carbon chain length, degree of fluorination, and the presence of carboxylic acid or sulfonic acid groups, with a notable V-shaped shift observed at C11.

Theranostic Nanoparticle Uptake in Patient Brain Tumors as Quantified by MP2RAGE T1 Mapping

PURPOSE/OBJECTIVE(S)

Modern radiation therapy techniques provide effective treatments for solid tumors, but there remain challenges with delivering high doses to elusive tumors without causing toxicity to surrounding normal tissue. Pre-clinical trials have demonstrated the theranostic properties of a recently developed gadolinium-based nanoparticle (Gd-NP). The first in-human clinical trial was conducted to assess the safety and dose tolerance of intravenous Gd-NPs in combination with whole brain radiotherapy and showed favorable results, including a significant correlation between tumor uptake and therapeutic response. The second, double-blinded, in-human clinical trial is underway in the US and aims to evaluate if brain-directed stereotactic radiation in conjunction with NPs will improve local tumor control compared to radiation alone. The current work investigates uptake patterns in brain tumors of 23 patients as quantified by magnetization prepared 2 rapid gradient echo (MP2RAGE) T1 mapping.

MATERIALS/METHODS

A phantom containing eight vials of NP-saline solutions at varying concentrations was created to examine the relationship between NP concentration and longitudinal relaxation (T1, in seconds). This relationship is known as relaxivity and is dependent on the contrast agent, field strength and T1 mapping sequence. A 3T MAGNETOM Vida scanner and MP2RAGE sequence were used to image the phantom and MP2RAGE T1 maps were calculated using Bloch equations (QMRLab software). Relaxivity was determined and applied to 23 patient T1 maps (pre- and post- Gd-NP administration) to calculate uptake on an individual tumor basis. Theranostic NP uptake was calculated for every voxel in each of 129 brain metastases and examined for patterns in quantity and distribution.

RESULTS

Average individual tumor uptake ranged from 0.02-0.12 mg/ml, where average overall uptake was equal to 0.05 mg/ml. A relationship between tumor diameter and mean NP concentration was observed and best represented by a power-based curve (R2 = 0.92). In contrast, patients with suspected placebo administration appeared to have no uptake and therefore no relationship with tumor diameter. The distribution of NP concentration within the tumor was also examined; on average, linear uptake profiles through tumor centroids (ant-post, left-right) demonstrated roughly gaussian patterns of uptake with lower concentrations at the tumor edges and higher concentrations at the tumor center. This pattern indicates robust tumor penetration and may have implications for amplifying radiation dose to hypoxic tumors.

CONCLUSION

Gd-NP uptake in brain metastases can be quantified using MP2RAGE T1 mapping. Uptake was determined for each voxel in each tumor volume, where a gaussian pattern of spatial concentrations was observed. This analysis procedure will be applied to the full data set, when available, to evaluate the impact of NP uptake (in conjunction with radiation therapy) within individual patients and individual tumors.

Trichlorfon blocks androgen synthesis and metabolism in rat immature Leydig cells

Trichlorfon is a widely used organophosphorus insecticide. It has been reported that it has reproductive toxicity to animal models. However, whether trichlorfon affects testosterone biosynthesis and metabolism remains unclear. In this study, we explored the effects of trichlorfon on the steroidogenesis and the expression of genes in androgen biosynthetic and metabolic cascades in immature Leydig cells isolated from pubertal male rats. Immature Leydig cells were treated with trichlorfon (0.5-50 µM) for 3 h. Trichlorfon significantly inhibited total androgen output under basal condition at 5 and 50 μM, and under LH- and cAMP-stimulated conditions at 50 μM. Trichlorfon also downregulated the expression of Star, Sod2, and Gpx1 and their proteins at 5 and 50 μM and the expression of Cyp11a1, Hsd3b1, Cyp17a1, and Srd5a1 at 50 μM. Trichlorfon significantly inhibited total androgen output at 50 μM, which was partially reversed by 400 μg/ml vitamin E, which alone had no effects on androgen output. In conclusion, trichlorfon downregulates the expression of steroidogenesis-related genes and antioxidants, which leads to a decrease in androgen production in rat immature Leydig cells.

UCHL1 Impairs Periodontal Ligament Stem Cell Osteogenesis in Periodontitis

Periodontitis comprises a series of inflammatory responses resulting in alveolar bone loss. The suppression of osteogenesis of periodontal ligament stem cells (PDLSCs) by inflammation is responsible for impaired alveolar bone regeneration, which remains an ongoing challenge for periodontitis therapy. Ubiquitin C-terminal hydrolase L1 (UCHL1) belongs to the family of deubiquitinating enzymes, which was found to play roles in inflammation previously. In this study, the upregulation of UCHL1 was identified in inflamed PDLSCs isolated from periodontitis patients and in healthy PDLSCs treated with tumor necrosis factor-α or interleukin-1β, and the higher expression level of UCHL1 was accompanied with the impaired osteogenesis of PDLSCs. Then UCHL1 was inhibited in PDLSCs using the lentivirus or inhibitor, and the osteogenesis of PDLSCs suppressed by inflammation was rescued by UCHL1 inhibition. Mechanistically, the negative effect of UCHL1 on the osteogenesis of PDLSCs was attributable to its negative regulation of mitophagy-dependent bone morphogenetic protein 2/Smad signaling pathway in periodontitis-associated inflammation. Furthermore, a ligature-induced murine periodontitis model was established, and the specific inhibitor of UCHL1 was administrated to periodontitis mice. The histological results showed increased active osteoblasts on alveolar bone surface and enhanced alveolar bone regeneration when UCHL1 was inhibited in periodontitis mice. Besides, the therapeutic effects of UCHL1 inhibition on ameliorating periodontitis were verified, as indicated by less bone loss and reduced inflammation. Altogether, our study proved UCHL1 to be a key negative regulator of the osteogenesis of PDLSCs in periodontitis and suggested that UCHL1 inhibition holds promise for alveolar bone regeneration in periodontitis treatment.

MiR-665 inhibits inflammatory response in microglia following spinal cord injury by targeting TREM2

OBJECTIVE

The purpose of this study was to uncover the role of microRNA-665 (miR-665) in protecting inflammatory response in microglia following spinal cord injury (SCI) and the underlying mechanism.

PATIENTS AND METHODS

The serum levels of miR-665 and TREM2 (triggering receptor expressed on myeloid 2) in SCI patients (n=24) and healthy subjects (n=24) were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Then, the serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were detected by enzyme-linked immunosorbent assay (ELISA). After lipopolysaccharide (LPS) induction in BV2 cells, the relative levels of miR-665 and TREM2 were detected by qRT-PCR, and relative levels of IL-6 and TNF-α in the culture medium were examined by ELISA. Next, TREM2, the target gene of miR-665, was determined by Dual-Luciferase reporter assay, and the relationship between the expression levels of TREM2 and miR-665 in SCI patients and BV2 cells was analyzed. Finally, the regulatory effects of miR-665 and TREM2 on IL-6 and TNF-α levels in the culture medium of LPS-induced BV2 cells were assessed.

RESULTS

It was found that miR-665 was downregulated in serum of SCI patients and LPS-induced BV2 cells, while TREM2 was upregulated. Silenced miR-665 or overexpressed TREM2 was involved in protecting inflammatory response following SCI. Besides, rescue experiments showed that miR-665 participated in the regulation of inflammatory response following SCI by targeting TREM2.

CONCLUSIONS

MiR-665 inhibits inflammatory response following SCI by targeting TREM2.

LncRNA MIR497HG inhibits proliferation and migration of retinal endothelial cells under high-level glucose treatment via miRNA-128-3p/SIRT1 axis

OBJECTIVE

The aim of this study was to elucidate the potential influence of MIR497HG on regulating proliferative capacity of human retinal endothelial cells (HRECs).

MATERIALS AND METHODS

Relative expression levels of MIR497HG, microRNA-128-3p (miRNA-128-3p) and SIRT1 in HRECs treated with different doses of glucose and mannitol were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Dual-Luciferase reporter gene assay was conducted to assess the interaction among MIR497HG, miRNA-128-3p, and SIRT1. In addition, the potential effects of MIR497HG/miRNA-128-3p/SIRT1 axis on proliferative and migratory capacities in HRECs were evaluated by Cell Counting Kit-8 (CCK-8), 5-Ethynyl-2'- deoxyuridine (EdU) and transwell assay, respectively.

RESULTS

High-level glucose (HG) treatment significantly downregulated MIR497HG and SIRT1 expression, whereas upregulated miRNA-128-3p expression in HRECs (p<0.05). MiRNA-128-3p was the target gene binding MIR497HG, and SIRT1 was the downstream gene of miRNA-128-3p. Overexpression of MIR497HG significantly attenuated proliferative and migratory abilities of HG-induced HRECs (p<0.05). Furthermore, decreased trends were partially reversed by overexpression of miRNA-128-3p or knockdown of SIRT1.

CONCLUSIONS

MIR497HG is downregulated after HG treatment. In addition, it suppresses the proliferation and migration of HRECs by targeting miRNA-128-3p/SIRT1 axis, thus influencing the progression of diabetic retinopathy.

Trichostatin A alleviates the process of breast carcinoma by downregulating LPAR5

OBJECTIVE

To elucidate the role of histone deacetylase inhibitor Trichostatin A (TSA) in affecting metastasis of breast carcinoma, and its molecular mechanism.

PATIENTS AND METHODS

LPAR5 levels in breast carcinoma tissues and paracancerous tissues were detected by quantitative real-time polymerase chain reaction (qRT-PCR), and its expression pattern was further verified in breast carcinoma cell lines. The relationship between LPAR5 and prognosis of breast carcinoma patients was analyzed. After TSA induction (100-400 nmol/L) for 6-48 h, the proliferative and migratory abilities of SKBR3 and MDA-MB-231 cells in overexpressing LPAR5 were examined by cell counting kit-8 (CCK-8), transwell and wound healing assay. By constructing a xenograft model in nude mice, the influences of TSA and LPAR5 on in vivo growth of breast carcinoma were examined.

RESULTS

LPAR5 was upregulated in breast carcinoma samples. High level of LPAR5 predicted higher rates of lymphatic metastasis and distant metastasis, as well as lower overall survival and progression-free survival in breast carcinoma patients. LPAR5 level was dose-dependently downregulated in TSA-induced SKBR3 and MDA-MB-231 cells. In addition, TSA induction dose-dependently declined proliferative ability, and time-dependently attenuated migratory ability in breast carcinoma cells. In vivo overexpression of LPAR5 in nude mice reversed the inhibitory effect of TSA on breast carcinoma growth.

CONCLUSIONS

TSA induction can suppress proliferative and migratory abilities in breast carcinoma by downregulating LPAR5.

Comparing the Performance of Different Instruments for Diagnosing Frailty and Predicting Adverse Outcomes among Elderly Patients with Gastric Cancer

OBJECTIVES

To examine the diagnostic performance of the Tilburg Frailty Indicator (TFI), 11-factor modified frailty index (mFI-11), and 5-factor modified frailty index (mFI-5) for frailty defined by Frailty Phenotype (FP), as well as to compare the predictive ability of TFI, mFI-11, and mFI-5 for adverse outcomes in hospital among elderly patients undergoing gastric cancer surgery.

DESIGN

A prospective cohort study.

SETTING

Hospitalization setting, Nanjing, China.

PARTICIPANTS

We recruited 259 elderly patients undergoing gastric cancer surgery from a tertiary hospital.

MEASUREMENTS

Frailty was assessed by the FP, TFI, mFI-11, and mFI-5 before surgery, respectively. The receiver operating characteristic (ROC) curves were plotted to compared the diagnostic performance of TFI, mFI-11, and mFI-5 using FP as the reference. ROC curves were used to examine the performance of TFI, mFI-11, and mFI-5 in predicting adverse outcomes. The area under the curve (AUC)>0.70 was regarded as an indicator of good performance.

RESULTS

The prevalence of frailty ranged from 8.5% (mFI-11) to 45.9% (TFI). The AUCs of TFI (AUC: 0.764, p<0.001) was significantly greater than that of mFI-11 (AUC: 0.600, p=0.033) and mFI-5 (AUC: 0.600, p=0.0311) in the detection of frailty defined by FP, with quite different sensitivity and specificity at their original cutoffs. TFI and mFI-11 both had statistically significant but similarly inadequate predictive accuracy for adverse outcomes in hospital, including total complications (AUCs: 0.618; 0.621), PLOS (AUCs: 0.593; 0.639), increased hospital costs (AUCs: 0.594; 0.624), and hypoproteinemia (AUCs: 0.573; 0.600). For the mFI-5, only the predictive ability for hypoproteinemia was statistically significant, with poor accuracy (AUC: 0.592, p<0.0055).

CONCLUSION

The TFI performed slightly better than mFI-11 and mFI-5 in our study. Moreover, future studies are needed to further determine an optimal frailty instrument with great diagnostic and predictive accuracy.

A polymorphic MYC response element in KBTBD11 influences colorectal cancer risk, especially in interaction with an MYC-regulated SNP rs6983267

Background

MYC is a well-established cancer driver gene regulating the expression of numerous genes, indicating that polymorphisms in MYC response elements could affect tumorigenesis through altering MYC regulation. We performed integrative multistage study to evaluate the effects of variants in MYC response elements and colorectal cancer (CRC) risk.

Patients and methods

We systematically integrated ChIP-Seq, DNase-Seq and transcription factor motif data to screen variants with potential ability to affect the MYC binding affinity. Then, we conducted a two-stage case-control study, totally consisting of 4830 CRC cases and 4759 controls in Chinese population to identify risk polymorphisms and interactions. The effects of risk variants were confirmed by functional assays in CRC LoVo, SW480 and HCT15 cells.

Results

We identified a novel polymorphism rs11777210 in KBTBD11 significantly associated with CRC susceptibility (P = 2.43 × 10-12). Notably, we observed a significant interaction between rs11777210 and MYC nearby rs6983267 (P-multi = 0.003, P-add = 0.005), subjects carrying rs6983267 GG and rs11777210 CC genotypes showing higher susceptibility to CRC (2.83-fold) than those carrying rs6983267 TT and rs11777210 TT genotypes. We further demonstrated that rs6983267 T > G increased MYC expression, and MYC bound to and negatively regulated KBTBD11 expression when the rs11777210 C risk allele was present. KBTBD11 was downregulated in tumor tissues, and KBTBD11 knockdown promoted cell proliferation and inhibited cell apoptosis.

Conclusion

The rs11777210 is a potential predictive biomarker of CRC susceptibility, and KBTBD11 functions as a putative tumor suppressor in tumorigenesis. Our study highlighted the high CRC risk of people carrying rs6983267 G and rs11777210 C alleles, and provided possible biological mechanism of the interaction.

Thrombin-reduced miR-27b attenuates platelet angiogenic activities in vitro via enhancing platelet synthesis of anti-angiogenic thrombospondin-1

Essentials It is unclear if platelet micro-RNAs can regulate de novo protein synthesis of platelets. Platelet de novo protein synthesis of thrombospondin-1 (TSP-1) was induced by thrombin. Thrombin stimulation in vitro altered platelet microRNA profiles, including decreased miR-27b. Decreased miR-27b hampers platelet angiogenic activities via enhancing de novo TSP-1 synthesis.

SUMMARY

Background Platelets can synthesize proteins upon activation. Platelets contain a number of microRNAs (miRNA) and a fully functional miRNA effector machinery. It is, however, unclear if platelet miRNAs can regulate protein synthesis of platelets, and whether the regulation may produce a physiological impact. Objectives To investigate if and how platelet miRNAs regulate de novo syntheses of angiogenic regulators and subsequently modulate platelet angiogenic activities. Methods and Results Microarray-based miRNA profiling showed that thrombin stimulation in vitro down- or up-regulated a number of platelet miRNAs, both in the total platelet miRNAs and in Ago2-associated miRNAs. Among those altered miRNAs, miR-27b was down-regulated in both the total and Ago2-immunoprecipitated miRNA profiles of platelets, which was confirmed by reverse transcription-quantitative PCR (RT-qPCR). Using western blotting assays, we showed that thrombin induced platelet de novo synthesis of thrombospondin-1, and that the level of thrombospondin-1 synthesis could reach a level of 3-5-fold higher than that before thrombin stimulation. With either the platelet precursor megakaryocyte cell line MEG-01 cells or mature platelets, we demonstrated that transfection of miR-27b mimic, but not the negative control of miRNA mimic, markedly reduced thrombospondin-1 protein levels. The latter subsequently enhanced platelet-dependent endothelial tube formation on matrigel. Conclusions Thrombin stimulation in vitro reduces platelet miR-27b levels that may markedly enhance thrombin-evoked platelet de novo synthesis of thrombospondin-1. Elevation of platelet miR-27b by transfection inhibits thrombospondin-1 synthesis, and subsequently enhances platelet pro-angiogenic activities. Hence, platelet activation-dependent reduction of miR-27b levels may represent a novel negative regulatory mechanism of platelet angiogenic activities.

Inverse association between plasma homocysteine concentrations and type 2 diabetes mellitus among a middle-aged and elderly Chinese population

BACKGROUND AND AIMS

Plasma homocysteine concentrations have been reported to be associated with type 2 diabetes mellitus (T2DM) with controversial findings. The aim of the present study was to investigate the association between plasma homocysteine concentrations and T2DM.

METHODS AND RESULTS

A cross-sectional study including 19,085 eligible participants derived from the Dongfeng-Tongji cohort was conducted. Plasma homocysteine concentrations were measured by Abbott Architect i2000 Automatic analyzer and T2DM was defined according to American Diabetes Association criteria. Logistic regression model was used to explore the association between plasma homocysteine concentrations and T2DM. The prevalence of T2DM was 19.0% in the whole population (mean age 62.9 years), 21.8% in males, and 17.1% in females. In the multivariable logistic regression analyses, compared with those in the lowest quintile, the OR (95% CI) of T2DM was 1.05 (0.92-1.21), 0.99 (0.86-1.14), 0.90 (0.78-1.05), and 0.77 (0.66-0.90) for quintile 2 to quintile 5 of homocysteine concentrations after adjustment for potential confounders (P for trend < 0.0001). Homocysteine concentrations were associated with decreased T2DM prevalence risk (OR = 0.88 per SD increase of homocysteine concentration; 95% CI: 0.84-0.93). A significant interaction between homocysteine concentrations and drinking status on T2DM prevalence risk was observed (P for interaction = 0.03). The inverse association of plasma homocysteine concentrations with T2DM prevalence risk was observed in non-drinkers but not in current drinkers.

CONCLUSION

Plasma homocysteine concentrations were inversely correlated with T2DM among a middle-aged and elderly Chinese population.

Associations between daily cooking duration and the prevalence of diabetes and prediabetes in a middle-aged and elderly Chinese population: A cross-sectional study

Experimental and epidemiological studies indicated that ambient air pollution was positively associated with diabetes. Few studies investigated the associations between household air pollution, for example, daily cooking duration and diabetes or prediabetes. We conducted a cross-sectional study to investigate the associations of daily cooking duration with the prevalence of diabetes and prediabetes among a middle-aged and elderly population. A total of 26 089 individuals (11 250 males and 14 839 females) derived from the Dongfeng-Tongji cohort study were included. Daily cooking duration was assessed by questionnaire. Diabetes and prediabetes were identified according to the criterion of American Diabetes Association. No significant association was observed between daily cooking duration and the prevalence risk of diabetes (odds ratio[OR] = 0.97, 95% confidence interval[CI]: [0.81-1.16], P for trend = .74); however, longer daily cooking duration was associated with higher prevalence risk of prediabetes (OR = 1.26, 95% CI: 1.07-1.47; P for trend = .003) and hyperglycemia (OR = 1.21, 95% CI: 1.05-1.41; P for trend = .005). Our study suggested that daily cooking duration was not associated with diabetes but with higher prevalence risk of prediabetes/hyperglycemia in a middle-aged and elderly Chinese population.

BMI, Waist Circumference and All-Cause Mortality in a Middle-Aged and Elderly Chinese Population

OBJECTIVE

To investigate the association of obesity and all-cause mortality in a sample of middle-aged and elderly population.

DESIGN AND SETTING

Information of participants was collected in the Dongfeng-Tongji study, a perspective cohort study of Chinese occupational population. The main outcome was risk of death after 8.5 years of follow-up.

PARTICIPANTS AND MEASUREMENTS

We examined the association of BMI, waist circumference (WC, and waist-height ratio (WHtR) with all-cause mortality in the Dongfeng-Tongji cohort study (n=26,143). Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CI) for all-cause mortality. Area under the receiver operating characteristic curves and net reclassification improvement (NRI) were used to calculate the power of prediction models.

RESULTS

During a mean of 8.5 years of follow-up, 2,246 deaths were identified. There is a U-shaped association of BMI with all-cause mortality in the middle-aged and elderly Chinese population. Compared with individuals with normal BMI, underweight was positively (HR=2.16, 95% CI: 1.73, 2.69) while overweight (HR=0.75, 95% CI: 0.67, 0.84) and obesity (HR=0.67, 95% CI: 0.56, 0.79) were negatively associated with all-cause mortality after adjustment for potential confounders including WC. In contrast, WC (Q5 vs. Q1, HR=1.55, 95% CI: 1.29, 1.86) and WHtR (Q5 vs.Q1, HR=1.69, 95% CI: 1.40, 2.04) were positively associated with mortality after further adjustment for BMI (P trend < 0.001). Addition of both BMI and WC into the all-cause mortality predictive model significantly increased AUC (P =0.0002) and NRI (NRI = 2.57%, P = 0.0007).

CONCLUSIONS

BMI and WC/WHtR were independently associated with all-cause mortality after mutual adjustment. Combination of BMI and WC/WHtR improved the predictive ability of all-cause mortality risk in the middle-aged and elderly population.

Abnormal intrinsic functional hubs in alcohol dependence: evidence from a voxelwise degree centrality analysis

OBJECTIVE

To explore the abnormal intrinsic functional hubs in alcohol dependence using voxelwise degree centrality analysis approach, and their relationships with clinical features.

MATERIALS AND METHODS

Twenty-four male alcohol dependence subjects free of medicine (mean age, 50.21±9.62 years) and 24 age- and education-matched male healthy controls (mean age, 50.29±8.92 years) were recruited. The alcohol use disorders identification test and the severity of alcohol dependence questionnaire (SADQ) were administered to assess the severity of alcohol craving. Voxelwise degree centrality approach was used to assess the abnormal intrinsic functional hubs features in alcohol dependence. Simple linear regression analysis was performed to investigate the relationships between the clinical features and abnormal intrinsic functional hubs.

RESULTS

Compared with healthy controls, alcohol dependence subjects exhibited significantly different degree centrality values in widespread left lateralization brain areas, including higher degree centrality values in the left precentral gyrus (BA 6), right hippocampus (BA 35, 36), and left orbitofrontal cortex (BA 11) and lower degree centrality values in the left cerebellum posterior lobe, bilateral secondary visual network (BA 18), and left precuneus (BA 7, 19). SADQ revealed a negative linear correlation with the degree centrality value in the left precentral gyrus (R²=0.296, P=0.006).

CONCLUSION

The specific abnormal intrinsic functional hubs appear to be disrupted by alcohol intoxication, which implicates at least three principal neural systems: including cerebellar, executive control, and visual cortex, which may further affect the normal motor behavior such as an explicit type of impaired driving behavior. These findings expand our understanding of the functional characteristics of alcohol dependence and may provide a new insight into the understanding of the dysfunction and pathophysiology of alcohol dependence.

Isolation and characterization of microsatellite markers for Dendranthema morifolium (Asteraceae) using next-generation sequencing

Dendranthema morifolium (Asteraceae) is a perennial herbaceous plant native to China. A long history of artificial crossings may have resulted in complex genetic background and decreased genetic diversity. To protect the genetic diversity of D. morifolium and enabling breeding of new D. morifolium cultivars, we developed a set of molecular markers. We used pyrosequencing of an enriched microsatellite library by Roche 454 FLX+ platform, to isolate D. morifolium simple sequence repeats (SSRs). A total of 32,863 raw reads containing 2251 SSRs were obtained. To test the effectiveness of these SSR markers, we designed primers by randomly selecting 100 novel SSRs, and amplified them across 60 cultivars representing five different petal shape groups. Sixteen SSRs were polymorphic with the number of alleles ranging from 6 to 19, and their expected and observed heterozygosities ranging from 0.477 to 0.848, and 0.250 to 0.804, respectively. The polymorphism information content ranged from 0.459 to 0.854 and the inbreeding coefficient ranged from -0.119 to 0.759. An unweighted pair-group method arithmetic average analysis was performed to survey the phylogenetic relationships of these 60 cultivars and five clusters were identified. These markers can be used for investigating genetic relationships and identifying elite alleles through linkage and association analyses.

Comparison of ILK and ERP29 expressions in benign and malignant pancreatic lesions and their clinicopathological significances in pancreatic ductal adenocarcinomas

INTRODUCTION

Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant tumor of the pancreas with poor prognosis. The lack of understanding of the molecular mechanisms of PDAC and biomarkers for early diagnosis might be two of the reasons for the poor prognosis of PDAC.

MATERIALS AND METHODS

ILK and ERP29 protein expressions in PDAC, peritumoral tissues, benign pancreatic lesions, and normal pancreatic tissues were measured by immunohistochemistry and the clinical and pathological significances of ILK and ERP29 in PDAC were analyzed.

RESULTS

The percentages of positive ILK and negative ERP29 expressions were significantly higher in PDAC tumors than in peritumoral tissues, benign pancreatic tissues, and normal pancreatic tissues (P < 0.01). Benign pancreatic lesions with positive ILK and negative ERP29 expressions exhibited dysplasia or intraepithelial neoplasia. The percentage of cases with positive ILK and negative ERP29 expressions was significantly lower in PDAC patients without lymph node metastasis and invasion, and having TNM stage I/II disease than in patients with lymph node metastasis, invasion, and TNM stage III/IV disease (P < 0.05 or P < 0.01). Kaplan-Meier survival analysis showed that positive ILK and negative ERP29 expressions were significantly associated with survival in PDAC patients (P < 0.001). Cox multivariate analysis revealed that positive ILK and negative ERP29 expressions were independent poor prognosis factors in PDAC patients.

CONCLUSIONS

Positive ILK and negative ERP29 expressions are associated with the progression of PDAC and poor prognosis in patients with PDAC.

Hypoxia stimulates the proliferation of rat neural stem cells by regulating the expression of metabotropic glutamate receptors: an in vitro study

Neural stem cells (NSCs) reside in not only developing, but also adult brain with specialized microenvironments that regulate their function. In vitro and in vivo studies have revealed strong regulatory links between hypoxic/ischemic insults and activation of NSCs. However, the underlying mechanisms remain unclear. Here, we show that proliferating NSCs isolated from rat E15.5 cortex expressed functional metabotropic glutamate receptor (mGluR) subtype 3-7. Hypoxic exposure regulated their expression in NSCs in mRNA and protein levels. Activation of mGluRs by glutamate or Trans-ACPD (a non subtype-selective mGluRs agonist) sensitized NSCs to the growth effects of hypoxia. Pharmacological blockade of ionotropic glutamate receptor (iGluR) using MK-801 did not attenuate the action of glutamate in NSCs. Furthemore, we used the group specific mGluR agonists DHPG, LY 379268 and L-AP4 to explore which mGluR subtypes are responsible for stimulating NSCs proliferation after hypoxia. The results suggested that hypoxia increased expression of group I mGluR5 and significantly enhanced the NSCs proliferation. We conclude that hypoxia regulates the expression of mGluRs in proliferating NSCs and the dynamic expression of mGluRs induced by hypoxia may be one of the mechanisms of hypoxia stimulated NSCs activation. Regulation of mGluRs in NSCs might be a useful tool in the experimental cell therapy of hypoxic/ischemic injuries of CNS.

Tetraspanin CD151 and integrin α6β1 mediate platelet-enhanced endothelial colony forming cell angiogenesis

ESSENTIALS: Platelet releasates (PRs) enhance endothelial colony forming cell (ECFC) angiogenesis. The impact of platelet membrane components on ECFC angiogenesis was studied by a tube formation assay. Platelets enhanced ECFC angiogenesis more potently than PR, via tetraspanin CD151 and integrin α6β1. Optimal enhancement of ECFC angiogenesis by platelets requires both membrane proteins and PR.

SUMMARY

BACKGROUND

Platelets promote angiogenesis of endothelial colony forming cells (ECFCs), with the underlying mechanisms not being fully understood.

OBJECTIVE

To investigate if platelets regulate the angiogenic property of ECFCs via mechanisms beyond platelet-released angiogenic regulators.

METHODS AND RESULTS

Endothelial colony forming cells were generated by ECFC-directed cell culture of peripheral blood mononuclear cells. Capillary-like tube formation of ECFCs was assessed using a Matrigel assay. Platelets promoted ECFC tube formation in both basic and complete ECFC medium. Importantly, the ECFC angiogenic responses induced by platelets were stronger than those induced by platelet releasates. Thus, the branching points of ECFC tube formation (30.5 ± 9.0/field, ECFC alone) were increased by platelet releasates (58.2 ± 8.3/field) and even more profoundly by platelets (95.5 ± 17.6/field), indicating that platelet membrane components also promoted ECFC tube formation. The latter was further supported by evidence that fixed platelets did enhance ECFC tube formation. Subsequent experiments revealed that the promotion was dependent on platelet-surface glycoproteins, as removal of sialic acid from platelet glycoproteins by neuraminidase abolished the enhancement. Furthermore, platelet-expressed, but not ECFC-expressed, CD151 was important for the enhancement, as pretreatment of platelets, but not ECFCs, with a CD151-blocking antibody attenuated the effect. Integrin α6β1 on both ECFCs and platelets also participated in platelet-promoted tube formation, as integrin α6 or β1 blockade of either cell type markedly or totally inhibited the phenomenon. Moreover, platelets exerted the enhancement via the Src-PI3K signaling pathway of ECFCs.

CONCLUSION

Platelet-enhanced ECFC angiogenesis requires platelet tetraspanin CD151 and α6β1 integrin, as well as ECFC α6β1 integrin and Src-PI3K signaling.

Protective effect of ferulic acid against 2,2'-azobis(2-amidinopropane) dihydrochloride-induced oxidative stress in PC12 cells

Oxidative stress is closely related to the pathogenesis of neurodegenerative disorders such as Parkinson's disease and Alzheimer's disease. However, the underlying antioxidant mechanisms of ferulic acid (FA) aganist oxidantive stress are poorly understood. We evaluated the potential protective effects of FA against 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced damage in PC12 cells. Our results indicated that pretreatment with FA prior to AAPH exposure significantly increased PC12 cell survival, and also increased catalase and superoxide dismutase activity. Furthermore, FA treatment reduced cellular lactate dehydrogenase release and malondialdehyde levels. It attenuated AAPH-induced apoptosis in PC12 cells, as determined by flow cytometric detection of annexin V. Reductions in mitochondrial membrane potential and accumulation of intracellular Ca2+ were also inhibited by FA treatment. These findings suggested that FA protected PC12 cells against AAPH-induced oxidative stress, and may be a neuroprotective agent.

PAR1-stimulated platelet releasate promotes angiogenic activities of endothelial progenitor cells more potently than PAR4-stimulated platelet releasate

BACKGROUND

Endothelial progenitor cells (EPCs) are important for endothelial regeneration and angiogenesis. Thrombin protease-activated receptor 1 (PAR1) PAR1 and PAR4 stimulation induces selective release of platelet proangiogenic and antiangiogenic regulators.

OBJECTIVE

To investigate if PAR1-stimulated platelet releasate (PAR1-PR) and PAR4-PR regulate angiogenic properties of EPCs in different manners.

METHODS AND RESULTS

EPCs were generated from peripheral mononuclear cell culture. Washed platelets (2 × 10(9) mL(-1)) were stimulated by PAR1-activating peptide (PAR1-AP; 10 μmol L(-1)) or PAR4-AP (100 μmol L(-1)) to prepare PAR1-PR and PAR4-PR, respectively. PAR1-PR or PAR4-PR had little influence on EPC proliferation. EPC migration experiments using a modified Boyden chamber showed that both platelet releasates facilitated EPC migration. As for in vitro tube formation on Matrigel, PAR1-PR and PAR4-PR similarly enhanced capillary-like network formation of EPCs in the complete EPC medium containing 10% FBS and a cocktail of growth factors, while PAR1-PR more profoundly increased EPC tube formation in basal culture medium supplemented with only 0.5% FBS than did PAR4-PR. The latter was confirmed in the murine angiogenesis model of subcutaneous Matrigel implantation. Moreover, blockade of vascular endothelial growth factor, stromal cell-derived factor 1α, or matrix metalloproteinases attenuated EPC migration and tube formation, suggesting a cooperation of these factors in the enhancements.

CONCLUSIONS

PAR1-PR enhances vasculogenesis more potently than PAR4-PR, and the enhancements require a cooperation of multiple platelet-derived angiogenic regulators.

Short communication: Evaluation of amino acid consumption and necessary profiles of Streptococcus thermophilus T1C2 in controlled pH batch fermentations

The objective of the present study was to elucidate the relationship between amino acid consumption and necessary profiles of Streptococcus thermophilus T1C2 to guide the design of media for high-cell-density culture. The amino acid consumption and necessary patterns of S. thermophilus T1C2 were investigated in the complete chemically defined medium. For amino acid consumption profiles throughout the growth of S. thermophilus T1C2, the most abundantly consumed amino acids were Gln and Arg, which accounted for 19 and 20% of total amino acids consumed, respectively. Asparagine, Thr, Ser, Ala, Val, Met, Leu, and Lys, consumptions of which ranged from 3 to 10% of total amino acids consumed, were the second most intensively consumed amino acids. For necessary amino acid patterns, the amount of Cys, which counted for 11% of total amino acids needed, was significantly higher than the amounts required for other amino acids in growth of S. thermophilus T1C2. The necessary amounts of Asp, Asn, Glu, Gln, Arg, Ala, Met, and Tyr ranked second, ranging from 5 to 8% of total amino acids needed. Compared with necessary amounts, the consumption of Asn, Thr, Ser, Gln, Arg, Ala, Val, Leu, Lys, His, and Phe exceeded the necessary amounts for growth of S. thermophilus T1C2 remarkably. Consumption of Gly, Met, Ile, Trp, and Pro was slightly higher than the necessary amounts. Consumption of Asp, Glu, Tyr, and Cys was lower than the necessary amounts. The overall consumption of amino acids exceeded the required amount for growth of S. thermophilus T1C2 almost 2.43 times, which implied a significant nitrogen wasting.

Meta-analysis on night shift work and risk of metabolic syndrome

This study aims to quantitatively summarize the association between night shift work and the risk of metabolic syndrome (MetS), with special reference to the dose-response relationship with years of night shift work. We systematically searched all observational studies published in English on PubMed and Embase from 1971 to 2013. We extracted effect measures (relative risk, RR; or odd ratio, OR) with 95% confidence interval (CI) from individual studies to generate pooled results using meta-analysis approach. Pooled RR was calculated using random- or fixed-effect model. Downs and Black scale was applied to assess the methodological quality of included studies. A total of 13 studies were included. The pooled RR for the association between 'ever exposed to night shift work' and MetS risk was 1.57 (95% CI = 1.24-1.98, pheterogeneity  = 0.001), while a higher risk was indicated in workers with longer exposure to night shifts (RR = 1.77, 95% CI = 1.32-2.36, pheterogeneity  = 0.936). Further stratification analysis demonstrated a higher pooled effect of 1.84 (95% CI = 1.45-2.34) for studies using the NCEP-ATPIII criteria, among female workers (RR = 1.61, 95% CI = 1.10-2.34) and the countries other than Asia (RR = 1.65, 95% CI = 1.39-1.95). Sensitivity analysis confirmed the robustness of the results. No evidence of publication bias was detected. The present meta-analysis suggested that night shift work is significantly associated with the risk of MetS, and a positive dose-response relationship with duration of exposure was indicated.

Evidence-based use of FFP: the influence of a priming strategy without FFP during CPB on postoperative coagulation and recovery in pediatric patients

Objective:

Although fresh frozen plasma (FFP) is one of the most commonly used hemostatic agents in clinical specialties today, there is little evidence available supporting its administration. Our present study observed the effects of a priming strategy without FFP during cardiopulmonary bypass (CPB) on postoperative coagulation and clinical recovery in pediatric patients, aiming to supply new evidence for evidence-based use of FFP.

Method:

Eighty pediatric patients with congenital heart disease undergoing cardiac surgery with CPB were randomized to receive either 10-20 ml/kg 4% succinylated gelatin (Gelofusine, GEL group, n = 40) or 1-2 units FFP (FFP group, n = 40) in the pump prime. Rapid-thromboelastography (r-TEG) and functional fibrinogen level were measured before skin incision and 15 minutes after heparin reversal. We recorded the volume of chest tube drainage, transfusion requirements and the dosage of pharmacological agents. The ventilation time, ICU length of stay and hospitalization time after surgery were also collected.

Results:

After heparin neutralization, there were significantly elevated levels of fibrinogen in the FFP group, which were manifested by r-TEG parameters MAf and FLEV. No significant differences were observed between the two groups in postoperative bleeding, transfusion requirements and the usage of pharmacological agents. Recovery time was also comparable between the two groups.

Conclusion:

In conclusion, prophylactic use of FFP in the priming solution does not provide clinical benefits as presumed. Artificial colloids, such as Gelofusine, can be used safely and effectively as a substitute for FFP in the pump prime. TEG is an effective assessment tool to evaluate postoperative coagulation function in pediatric patients.

Expression of p53 upregulated modulator of apoptosis (PUMA) and C-myb in gallbladder adenocarcinoma and their pathological significance

PURPOSE

An increasing number of studies have shown that PUMA and C-myb signaling pathways are involved in various human cancers including colon carcinomas. However, few studies have examined gallbladder cancer specimens, and little is known about the clinical and pathological significance signaling changes may have in gallbladder adenocarcinoma. This study has investigated the expression of PUMA and C-myb in benign and malignant lesions of gallbladder and its pathological significance.

METHODS

Tissue specimens from 108 gallbladder adenocarcinoma patients, 46 adjacent tissues, 15 cases of adenomatous polyps, and 35 surgical specimens from chronic cholecystitis patients were routinely paraffin embedded and sectioned. PUMA and C-myb expressions were detected with EnVision immunohistochemistry.

RESULTS

Positive rates of PUMA and C-myb are significantly higher in gallbladder adenocarcinoma tissues than that in the other three (P < 0.01). Gallbladder epithelial cells in PUMA and/or C-myb positive benign cases manifest moderate to severe atypical dysplasia. Positive rates of PUMA and C-myb in well-differentiated tumors with maximum diameter of <2 cm and with no lymph node metastasis and invasion of the surrounding tissues are significantly lower than that in those poorly differentiated cases with maximum diameter of ≥ 2 cm, lymph node metastasis, and invasion of the surrounding tissues (P < 0.05 or P < 0.01). The postoperative survival of patients whose tumor specimens are positive for PUMA and C-myb is significantly shorter than that of those who are negative for both markers (P < 0.05 or P < 0.01).

CONCLUSIONS

Our results have demonstrated that PUMA and C-myb positive gallbladder tumors progress rapidly, are prone to metastasis, possess strong invasive ability, and have poor prognosis.

A pharmacogenetic study of docetaxel and thalidomide in patients with castration-resistant prostate cancer using the DMET genotyping platform

The anticancer agent docetaxel shows significant inter-individual variation in its pharmacokinetic and toxicity profile. Thalidomide is an active anticancer agent and also shows wide pharmacological variation. Past pharmacogenetic research has not explained this variation. Patients with prostate cancer enrolled in a randomized phase II trial using docetaxel and thalidomide versus docetaxel alone were genotyped using the Affymetrix DMET 1.0 platform, which tests for 1256 genetic variations in 170 drug disposition genes. Genetic polymorphisms were analyzed for associations with clinical response and toxicity. In all, 10 single-nucleotide polymorphisms (SNPs) in three genes were potentially associated with response to therapy: peroxisome proliferator-activated receptor-delta (PPAR-delta), sulfotransferase family, cytosolic, 1C, member 2 (SULT1C2) and carbohydrate (chondroitin 6) sulfotransferase 3 (CHST3). In addition, 11 SNPs in eight genes were associated with toxicities to treatment: spastic paraplegia 7 (pure and complicated autosomal recessive) (SPG7), CHST3, cytochrome P450, family 2, subfamily D, polypeptide 6 (CYP2D6), N-acetyltransferase 2 (arylamine N-acetyltransferase) (NAT2), ATP-binding cassette, sub-family C (CFTR/MRP), member 6 (ABCC6), ATPase, Cu++ transporting, alpha polypeptide (ATP7A), cytochrome P450, family 4, subfamily B, polypeptide 1 (CYP4B1) and solute carrier family 10 (sodium/bile acid cotransporter family), member 2 (SLC10A2). Genotyping results between drug metabolizing enzymes and transporters (DMET) and direct sequencing showed >96% of concordance. These findings highlight the role that non-CYP450 metabolizing enzymes and transporters may have in the pharmacology of docetaxel and thalidomide.

Fine mapping of E(kp)-1, a locus associated with silkworm (Bombyx mori) proleg development

The silkworm homeotic mutant E(kp) has a pair of rudimentary abdominal legs, called prolegs, in its A2 segment. This phenotype is caused by a single dominant mutation at the E(kp)-1 locus, which was previously mapped to chromosome 6. To explore the possible association of Hox genes with proleg development in the silkworm, a map-based cloning strategy was used to isolate the E(kp)-1 locus. Five E(kp)-1-linked simple sequence repeat markers on chromosome 6 were used to generate a low-resolution map with a total genetic distance of 39.5 cM. Four additional cleaved amplified polymorphic sequence markers were developed based on the initial map. The closest marker to E(kp)-1 was at a genetic distance of 2.7 cM. A high-resolution genetic map was constructed using nine BC1 segregating populations consisting of 2396 individuals. Recombination suppression was observed in the vicinity of E(kp)-1. Four molecular markers were tightly linked to E(kp)-1, and three were clustered with it. These markers were used to screen a BAC library. A single bacterial artificial chromosome (BAC) clone spanning the E(kp)-1 locus was identified, and E(kp)-1 was delimited to a region less than 220 kb long that included the Hox gene abdominal-A and a non-coding locus, iab-4. These results provide essential information for the isolation of this locus, which may shed light on the mechanism of proleg development in the silkworm and possibly in Lepidoptera.

Evaluation of the NK2 homeobox 1 gene (NKX2-1) as a Hirschsprung's disease locus

Hirschsprung's disease (HSCR, colonic aganglionosis) is an oligogenic entity that usually requires mutations in RET and other interacting loci. Decreased levels of RET expression may lead to the manifestation of HSCR. We previously showed that RET transcription was decreased due to alteration of the NKX2-1 binding site by two HSCR-associated RET promoter single nucleotide polymorphisms (SNPs). This prompted us to investigate whether DNA alterations in NKX2-1 could play a role in HSCR by affecting the RET-regulatory properties of the NKX2-1 protein. Our initial study on 86 Chinese HSCR patients revealed a Gly322Ser amino acid substitution in the NKX2-1 protein. In this study, we have examined 102 additional Chinese and 70 Caucasian patients and 194 Chinese and 60 Caucasian unselected, unrelated, subjects as controls. The relevance of the DNA changes detected in NKX2-1 by direct sequencing were evaluated using bioinformatics, reporter and binding-assays, mouse neurosphere culture, immunohistochemistry and immunofluorescence techniques. Met3Leu and Pro48Pro were identified in 2 Caucasian and 1 Chinese patients respectively. In vitro analysis showed that Met3Leu reduced the activity of the RET promoter by 100% in the presence of the wild-type or HSCR-associated RET promoter SNP alleles. The apparent binding affinity of the NKX2-1 mutated protein was not decreased. The Met3Leu mutation may affect the interaction of NKX2-1 with its protein partners. The absence of NKX2-1 expression in mouse but not in human gut suggests that the role of NKX2-1 in gut development differs between the two species. NKX2-1 mutations could contribute to HSCR by affecting RET expression through defective interactions with other transcription factors.

Hirschsprung disease, associated syndromes and genetics: a review

Hirschsprung disease (HSCR, aganglionic megacolon) represents the main genetic cause of functional intestinal obstruction with an incidence of 1/5000 live births. This developmental disorder is a neurocristopathy and is characterised by the absence of the enteric ganglia along a variable length of the intestine. In the last decades, the development of surgical approaches has importantly decreased mortality and morbidity which allowed the emergence of familial cases. Isolated HSCR appears to be a non-Mendelian malformation with low, sex-dependent penetrance, and variable expression according to the length of the aganglionic segment. While all Mendelian modes of inheritance have been described in syndromic HSCR, isolated HSCR stands as a model for genetic disorders with complex patterns of inheritance. The tyrosine kinase receptor RET is the major gene with both rare coding sequence mutations and/or a frequent variant located in an enhancer element predisposing to the disease. Hitherto, 10 genes and five loci have been found to be involved in HSCR development.

Knowledge and willingness toward living organ donation: a survey of three universities in Changsha, Hunan Province, China

BACKGROUND

This study was conducted to clarify the knowledge and attitudes of Chinese university students regarding living organ donation and analyze the determinants impacting their decisions.

METHODS

A questionnaire was delivered to college students chosen by random assignment. The data was analyzed by Statistics Package for Social Science (SPSS) software.

RESULTS

Of 434 participants, 49.8% indicated they would be willing to be living organ donors, 58.4% believed living organ donation could ease the organ shortage, 48.2% thought that the recovery rate of recipients of living organ donors transplants was equal to or even better than deceased donation, 62.4% designated relatives as their most probable recipients, 48.0% argued that partial compensation was an effective method to increase live organ donation, and 53.7% wished to donate through transplantation centers. According to univariate analysis, attitudes regarding the value of life, relationship between body integrity and health as well as body integrity and conventional culture were factors that impacted on an individual's decision. Students' knowledge of the value of living organ transplantation and their economic background were considered to be determinants of individual willingness. Furthermore, the operation's impact on quality of life and postoperative complications were additional concerns. Multivariate analysis indicated that other factors influencing students' willingness to donate included attitudes toward the relationship between body integrity and health, beliefs regarding body integrity and conventional culture, value of living donor organ transplantation, economic background of students, and anxiety about the impact on postoperative complications.

CONCLUSIONS

Numerous students were willing to participate in living organ donation. At the same time, social education and advertisements for living organ donation were far from adequate, having little or no influence on the decision-making process.

A pharmacogenetic study of docetaxel and thalidomide in patients with androgen-independent prostate cancer (AIPC) using targeted human DMET genotyping platform

3580

Background: Pharmacogenetic research holds the promise of individualizing cancer therapy by reducing inter-individual variability in drug response, thus enhancing efficacy and reducing toxicity. Past research has been limited due to the lack of a robust genotyping platform that can screen for single nucleotide polymorphisms (SNPs) in the dozens of genes known to be involved in drug disposition. We pilot tested the new Affymetrix Targeted Human Drug Metabolizing Enzymes and Transporter (DMET) 1.0 panel in an exploratory study of docetaxel and thalidomide. The DMET 1.0 panel tests for 1,229 genetic variations in 169 drug disposition genes, including 49 CYP450 genes, 73 non-CYP genes, and 47 transporters. Methods: DNA samples from 47 patients with AIPC enrolled in a randomized phase II trial using docetaxel and thalidomide vs. docetaxel alone were genotyped using the DMET 1.0 panel. Patients’ response was determined using RECIST criteria. Toxicities were graded using the NCI-CTC, and patients were identified if they experienced grade 3 or 4 toxicity. Given the distinct side effect profiles of these two drugs, specific toxicities were assigned as being due to either docetaxel or thalidomide. An association between the SNP parameters and clinical response or toxicity was tested using Mehta’s modification to Fisher’s exact test. Reported results were limited to those where p<0.01. Results: Six SNPs in three genes were associated with response to therapy: PPAR-delta (p=0.0011), SULT1C2 (p=0.0083), and CHST3 (4 SNPs, p=0.0001 to 0.0034). For toxicities associated with docetaxel, five SNPs in three genes were identified: UGT1A1 (2 SNPs, p=0.0009 to 0.0094), UGT1A9 (2 SNPs, p=0.0016 to 0.0096), and CYP2A7 (p=0.0027). SNPs in CYP2B6 (p=0.0033), ABCC1 (p=0.0036), and ABCC6 (p=0.0075) were associated with toxicities from thalidomide. Conclusion: We identified nine genes in which SNPs were potentially significantly associated with clinical response and toxicity to treatment. These results highlight the important role that non-CYP450 and phase II drug metabolizing enzymes may play in the efficacy and disposition of docetaxel and thalidomide. Confirmatory studies are warranted.

No significant financial relationships to disclose.

SMYD3 tandem repeats polymorphism is not associated with the occurrence and metastasis of hepatocellular carcinoma in a Chinese population

A variable number of tandem repeats (VNTR) polymorphism in regulatory region of SMYD3 coding for histone methyltransferase has been shown to be associated with colorectal cancer, hepatocellular carcinoma (HCC), and breast cancer in Japanese population. Aim of the study is to investigate the potential association between the functional SMYD3 tandem repeats polymorphism and HCC in Chinese population.

MATERIAL AND METHODS

The case-control study included 200 HCC patients and 261 healthy controls. The VNTR polymorphism in the promoter of SMDY3 was genotyped by PCR and direct-sequencing analysis. Odds ratio and 95% confidence interval were used to estimate the association between the polymorphisms and risk of HCC.

RESULTS

The allele frequencies for SMYD3 2 and 3 repeats were 15.71% and 84.29% among controls; and 12.75%, and 87.25% among cases (P = 0.22). The odds ratio for 3/3 versus 2/2 and 2/3 genotypes was 1.30 (P = 0.18). The frequencies of 3 alleles were not increased with HCC stage increased (trend test, P = 0.45).

CONCLUSION

SMYD3 polymorphism is not associated with the occurrence and metastasis of HCC in Chinese population.

Correlation between genetic variations in Hox clusters and Hirschsprung's disease

Interactions between migrating neural crest cells and the environment of the gut are crucial for the development of the enteric nervous system (ENS). A key signalling mediator is the RET-receptor-tyrosine-kinase which, when defective, causes Hirschprung's disease (HSCR, colon aganglionosis). RET mutations alone cannot account for the variable HSCR phenotype, invoking interactions with as yet unknown, and probably inter-related, loci involved in ENS development. Homeobox (HOX) genes have a major role in gut development as depicted by the enteric Hox code. We investigated whether DNA alterations in HOX genes, either alone or in combination with RET, are implicated in HSCR. Genotyping effort was minimized by applying the HapMap data on Han Chinese from Beijing (CHB). 194 HSCR patients and 168 controls were genotyped using Sequenom technology for 72 tag, single nucleotide polymorphisms (SNPs) distributed along the HOX clusters. The HapMap frequencies were compared to those in our population and standard statistics were used for frequency comparisons. The multifactor-dimensionality-reduction method was used for multilocus analysis, in which RET promoter SNP genotypes were included. Genetic interactions were found between two HOX loci (5'-HOXA13 and 3'UTR-HOXB7) and the RET loci tested. Minor allele frequencies (MAF) of the SNPs tested in our sample were not significantly different from those reported by HapMap when the sample sizes of the populations compared were considered. This is the first evaluation of the HOX genes in HSCR and the first application of HapMap data in a Chinese population. The interacting HOX loci may affect the penetrance of the RET risk allele. HapMap data for the CHB population correlated well with the general Chinese population.

Functional polymorphisms in cell death pathway genes FAS and FASL contribute to risk of lung cancer

BACKGROUND

The FAS and FASL system plays a key role in regulating apoptotic cell death and corruption of this signalling pathway has been shown to participate in immune escape and tumorigenesis. There is reduced expression of FAS but elevated expression of FASL in many types of human cancers including lung cancer. We recently reported an association between functional polymorphisms in FAS (-1377G-->A) and FASL (-844T-->C) and risk of oesophageal cancer.

OBJECTIVE

To examine the contribution of these polymorphisms to risk of developing lung cancer.

METHODS

Genotypes of 1000 lung cancer patients and 1270 controls were analysed by PCR based restriction fragment length polymorphism. Associations with risk of lung cancer were estimated by logistic regression.

RESULTS

Compared with non-carriers, there was a 1.6 fold excess risk of developing lung cancer for carriers of the FAS -1377AA genotype (odds ratio (OR) 1.59, 95% confidence interval (CI) 1.21 to 2.10; p = 0.001), and 1.8 fold excess risk (OR 1.79, 95% CI 1.26 to 2.52; p = 0.001) for carriers of FASL -844CC. Gene-gene interaction of FAS and FASL polymorphisms increased risk of lung cancer in a multiplicative manner (OR for the carriers of both FAS -1377AA and FASL -844CC genotypes 4.18, 95% CI 2.83 to 6.18). Gene-environment interaction of FAS or FASL polymorphism and smoking associated with increased risk of lung cancer was also found.

CONCLUSION

These results are consistent with our initial findings in oesophageal cancer and further support the hypothesis that the FAS and FASL triggered apoptosis pathway plays an important role in human carcinogenesis.

A novel T-77C polymorphism in DNA repair gene XRCC1 contributes to diminished promoter activity and increased risk of non-small cell lung cancer

X-ray repair cross-complementing 1 (XRCC1) plays a key role in DNA base excision repair and cells lacking its activity are hypersensitive to DNA damage. Recently, we reported a SNP (rs3213245, -77T>C) in the XRCC1 gene 5' untranslated region (UTR) was significantly associated with the risk of developing esophageal squamous-cell carcinoma. Computer analysis predicted that this SNP was in the core of Sp1-binding motif, which suggested its functional significance. Gel shift and super shift assays confirmed that -77T>C polymorphic site in the XRCC1 promoter was within the Sp1-binding motif and the T>C substitution greatly enhanced the binding affinity of Sp1 to this region. Luciferase assays indicated that the Sp1-high-affinity C-allelic XRCC1 promoter was associated with a reduced transcriptional activity. The association between -77T>C and three other amino-acid substitution-causing polymorphisms in XRCC1 and risk of lung cancer was examined in 1024 patients and 1118 controls and the results showed that only the -77T>C polymorphism was significantly associated with an increased risk of developing lung cancer. Multivariate logistic regression analysis found that an increased risk of lung cancer was associated with the variant XRCC1 -77 genotypes (TC and CC) compared with the TT genotype (OR=1.46, 95% CI=1.18-1.82; P=0.001) and the increased risk was more pronounced in smokers (OR=1.63, 95% CI=1.20-2.21) than in non-smokers (OR=1.28, 95% CI=0.94-1.76). Taken together, these results showed that the functional SNP -77T>C in XRCC1 5'UTR was associated with cancer development owing to the decreased transcriptional activity of C-allele-containing promoter with higher affinity to Sp1 binding.

Radiation-induced changes in gene expression in the silkworm revealed by serial analysis of gene expression (SAGE)

Serial analysis of gene expression (SAGE) was used to examine the profile of expressed genes during embryonic development in the domesticated silkworm, Bombyx mori, after irradiation with Cobalt-60. A comparison of the SAGE sequence tags derived from irradiated embryos with those from normal embryos revealed 673 differentially expressed genes (P < 0.01 and at least three folds change). Of these, 292 genes were highly expressed in normal embryos and 381 genes were highly expressed in irradiated embryos. These results provide valuable information for understanding the mechanisms of radiation-induced changes in gene expression. In addition, it was noted that the generation of longer cDNA fragments from SAGE tags is an efficient way to identify genes, thereby facilitating the analysis of large numbers of unknown genes.

A common polymorphism in the 3'UTR of cyclooxygenase 2/prostaglandin synthase 2 gene and risk of lung cancer in a Chinese population

Cyclooxygenases (COXs) are key enzymes that convert arachidonic acid to prostaglandins. Overexpression of COX-2, one of the COX isozymes, has been shown to be an early event in lung carcinogenesis and may play an important role in lung cancer development. A common single nucleotide polymorphism, T8473C, located within a potential functional region in the 3'UTR of COX-2 gene was identified and we hypothesized that this COX-2 variant is associated with lung cancer risk. To test this hypothesis, we genotyped this variant in a case-control study of 322 histologically-confirmed lung cancer patients and 323 age and sex frequency-matched cancer-free controls in a Chinese population. The results showed that the frequencies of variant genotypes 8473CT/CC were significantly less common in the cases (27.3%) than in the controls (35.3%) (P=0.034), suggesting that the 8473C allele was protective against lung cancer. Multivariate logistic regression analyses revealed that the COX-2 variant genotypes (8473CT/CC) were associated with a significantly decreased risk of lung cancer compared with the 8473TT wild-type homozygotes (OR=0.64, 95% CI=0.45-0.92). When we defined the reference group as non-smokers having the 8473CT/CC variant genotypes, the smokers with the 8473TT wild-type genotype had the greatest risk (adjusted OR=5.28, 95% CI=3.10-9.00). These findings indicate that the COX-2 T8473C polymorphism may contribute to lung cancer susceptibility in the Chinese population. Further larger molecular epidemiological studies are warranted to confirm these findings.

Bichromatic slowing and collimation to make an intense helium beam

The bichromatic force has been used to both slow and collimate a beam of metastable 2(3)S He atoms (He*). The collimation capture range is an extraordinary +/-85 m/s corresponding to approximately 0.18 radians from our source. Both slowing and collimation were accomplished in the unprecedented short distance of approximately 5 cm each. The overall brightness increase is x3200, and there is potential for considerably more.