Polymorphisms in the ERCC5 Gene and Risk of Esophageal Squamous Cell Carcinoma (ESCC) in Eastern Chinese Populations

Background

Excision repair cross complementing group 5 (ERCC5 or XPG) plays an important role in regulating DNA excision repair; its functional single nucleotide polymorphisms (SNPs) may alter DNA repair capacity and thus contribute to cancer risk.

Methodology/Principal Findings

In a hospital-based case-control study of 1115 esophageal squamous cell carcinoma (ESCC) cases and 1117 cancer-free controls, we genotyped three potentially functional SNPs of ERCC5 (SNPs, rs2296147T>C, rs2094258C>T and rs873601G>A) and estimated crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for their associations with risk of ESCC using unconditional logistic regression models. We also calculated false-positive report probabilities (FPRPs) for significant findings. We found that compared with the TT genotype, ERCC5 rs2296147 C variant genotypes were associated with a significantly lower ESCC risk (CT: adjusted OR = 0.76, 95% CI = 0.63–0.93, CT/CC: adjusted OR = 0.80, 95% CI = 0.67–0.96); however, this risk was not observed for the other two SNPs (rs2094258C>T and rs873601 G>A), nor in further stratification and haplotype analysis.

Conclusions/Significances

These findings suggested that ERCC5 polymorphisms may contribute to risk of ESCC in Eastern Chinese populations, but the effect was weak and needs further validation by larger population-based case-control studies.     

An intronic variant in the GRP78, a stress-associated gene, improves prediction for liver cirrhosis in persistent HBV carriers

Background

Our previous study indicated that a common variant (rs430397 G>A) in the intron 5 of glucose-regulated protein 78 (GRP78) gene was associated with risk and prognosis of primary hepatocellular carcinoma (HCC), including HBV- and cirrhosis-related HCC. rs430397 polymorphism may be a contributing factor or biomarker of HBV infection or HBV-related cirrhosis.

Methodology/Principal Findings

539 non-HBV-infected individuals, 205 self-limited infection and 496 persistent HBV infection were recruited between January 2001 and April 2005 from the hospitals in Southern China. Genomic DNA was genotyped for rs430397. The associations between the variation and susceptibility to liver cirrhosis (LC) in persistent HBV infection were examined. We observed that individuals carrying allele rs430397A were more likely to become HBV-related LC. When persistently infected patients were divided into four subgroups, patients with phase IV had an increased allele A and genotype AG compared with phase I and/or phase III. Decreased serum albumin and prolonged plasma prothrombin time (PT) were showed in LC patients carrying genotype AA. Furthermore, rs430397 genotype had an increased susceptibility to LC with dose-dependent manners (P-trend = 0.005), and the genotype did constitute a risk factor for the development of advanced LC (Child–Pugh classification C and B, P-trend = 0.021).

Conclusions/Significance

rs430397 polymorphism may be a contributing factor to LC in persistent HBV carriers.     

Single nucleotide polymorphisms of Toll-like receptor 4 decrease the risk of development of hepatocellular carcinoma

Background

Toll-like receptor 4 (TLR4) is a key innate immunity receptor that initiates an inflammatory response. Growing evidence suggests that mutation of TLR4 gene may play a role in the development of cancers. This study aimed to investigate the temporal relationship of single nucleotide polymorphisms of TLR4 and the risk of hepatocellular carcinoma, a single center-based case-control study was conducted.

Methods

A systematic genetic analysis of sequence variants of TLR4 by evaluating ten single-nucleotide polymorphisms was performed from 216 hepatocellular carcinoma cases and 228 controls.

Results

Six single nucleotide polymorphisms of the TLR4 in the 5′-untranslated region and intron were associated with risk of hepatocellular carcinoma. Individuals carrying the heterozygous genotypes for the rs10759930, rs2737190, rs10116253, rs1927914, rs12377632 and rs1927911 had significantly decreased risk of hepatocellular carcinoma (adjusted odds ratio [OR], from 0.527 to 0.578, P<0.01) comparing with those carrying wild-type homozygous genotypes. In haplotype analysis, one haplotype (GCCCTTAG) of TLR4 was associated significantly with decrease of the occurrence of hepatocellular carcinoma (OR, 0.556, 95% confidence interval [CI], 0.407–0.758, P = 0.000).

Conclusions

Collectively, these results suggested that the risk of hepatocellular carcinoma was associated with TLR4 sequence variation. TLR4 single nucleotide polymorphisms may play an important protective role in the development of hepatocellular carcinoma.     

Does High C-reactive Protein Concentration Increase Atherosclerosis? The Whitehall II Study

Background

C-reactive protein (CRP), a marker of systemic inflammation, is associated with risk of coronary events and sub-clinical measures of atherosclerosis. Evidence in support of this link being causal would include an association robust to adjustments for confounders (multivariable standard regression analysis) and the association of CRP gene polymorphisms with atherosclerosis (Mendelian randomization analysis).

Methodology/Principal Findings

We genotyped 3 tag single nucleotide polymorphisms (SNPs) [+1444T>C (rs1130864); +2303G>A (rs1205) and +4899T>G (rs 3093077)] in the CRP gene and assessed CRP and carotid intima-media thickness (CIMT), a structural marker of atherosclerosis, in 4941 men and women aged 50–74 (mean 61) years (the Whitehall II Study). The 4 major haplotypes from the SNPs were consistently associated with CRP level, but not with other risk factors that might confound the association between CRP and CIMT. CRP, assessed both at mean age 49 and at mean age 61, was associated both with CIMT in age and sex adjusted standard regression analyses and with potential confounding factors. However, the association of CRP with CIMT attenuated to the null with adjustment for confounding factors in both prospective and cross-sectional analyses. When examined using genetic variants as the instrument for serum CRP, there was no inferred association between CRP and CIMT.

Conclusions/Significance

Both multivariable standard regression analysis and Mendelian randomization analysis suggest that the association of CRP with carotid atheroma indexed by CIMT may not be causal.     

A 3' UTR SNP in COL18A1 is associated with susceptibility to HBV related hepatocellular carcinoma in Chinese: three independent case-control studies

Background

Accumulated evidences indicate that single nucleotide polymorphisms (SNP) in angiogenesis and tumorigenesis related genes are associated with risk of Hepatocellular carcinoma (HCC). COL18A1 encodes the precursor of endostatin, which is a broad-spectrum angiogenesis inhibitor, and we speculate that SNPs in COL18A1 may be associated with susceptibility to HCC.

Methods and Findings

We carried out a 2-stage association study in 3 independent case-control groups in a total of 1067 chronic hepatitis B (CHB) patients and 808 hepatitis B virus (HBV) related HCC patients in Han Chinese. Four SNPs which can represent all potential functional SNPs with MAF>0.1 recorded in HapMap database were genotyped using TaqMan methods. Levels of total COL18A1 mRNA were also examined using quantitative real-time RT-PCR. We found that rs7499 located in 3′-UTR to be strongly associated with HBV related HCC (P_combined = 0.0000005, OR = 0.72, 95%CI = 0.63–0.82). COL18A1 mRNA expression was significantly decreased as the disease progressed (P = 0.000026).

Conclusion

These findings indicate that COL18A1 rs7499 may contribute to the risk of HCC in Han Chinese.     

Investigation of a genome wide association signal for obesity: synthetic association and haplotype analyses at the melanocortin 4 receptor gene locus

Background

Independent genome-wide association studies (GWAS) showed an obesogenic effect of two single nucleotide polymorphisms (SNP; rs12970134 and rs17782313) more than 150 kb downstream of the melanocortin 4 receptor gene (MC4R). It is unclear if the SNPs directly influence MC4R function or expression, or if the SNPs are on a haplotype that predisposes to obesity or includes functionally relevant genetic variation (synthetic association). As both exist, functionally relevant mutations and polymorphisms in the MC4R coding region and a robust association downstream of the gene, MC4R is an ideal model to explore synthetic association.

Methodology/Principal Findings

We analyzed a genomic region (364.9 kb) encompassing the MC4R in GWAS data of 424 obesity trios (extremely obese child/adolescent and both parents). SNP rs12970134 showed the lowest p-value (p = 0.004; relative risk for the obesity effect allele: 1.37); conditional analyses on this SNP revealed that 7 of 78 analyzed SNPs provided independent signals (p≤0.05). These 8 SNPs were used to derive two-marker haplotypes. The three best (according to p-value) haplotype combinations were chosen for confirmation in 363 independent obesity trios. The confirmed obesity effect haplotype includes SNPs 3′ and 5′ of the MC4R. Including MC4R coding variants in a joint model had almost no impact on the effect size estimators expected under synthetic association.

Conclusions/Significance

A haplotype reaching from a region 5′ of the MC4R to a region at least 150 kb from the 3′ end of the gene showed a stronger association to obesity than single SNPs. Synthetic association analyses revealed that MC4R coding variants had almost no impact on the association signal. Carriers of the haplotype should be enriched for relevant mutations outside the MC4R coding region and could thus be used for re-sequencing approaches. Our data also underscore the problems underlying the identification of relevant mutations depicted by GWAS derived SNPs.     

High protein binding and cidal activity against penicillin-resistant S. pneumoniae: a cefditoren in vitro pharmacodynamic simulation

Background

Although protein binding is a reversible phenomenon, it is assumed that antibacterial activity is exclusively exerted by the free (unbound) fraction of antibiotics.

Methodology/Principal Findings

Activity of cefditoren, a highly protein bound 3^rd generation cephalosporin, over 24h after an oral 400 mg cefditoren-pivoxil bid regimen was studied against six S. pneumoniae strains (penicillin/cefditoren MICs; µg/ml): S1 (0.12/0.25), S2 (0.25/0.25), S3 and S4 (0.5/0.5), S5 (1/0.5) and S6 (4/0.5). A computerized pharmacodynamic simulation with media consisting in 75% human serum and 25% broth (mean albumin concentrations = 4.85±0.12 g/dL) was performed. Protein binding was measured. The cumulative percentage of a 24h-period that drug concentrations exceeded the MIC for total (T>MIC) and unbound concentrations (fT>MIC), expressed as percentage of the dosing interval, were determined. Protein binding was 87.1%. Bactericidal activity (≥99.9% initial inocula reduction) was obtained against strains S1 and S2 at 24h (T>MIC = 77.6%, fT>MIC = 23.7%). With T>MIC of 61.6% (fT>MIC = 1.7%), reductions against S3 and S4 ranged from 90% to 97% at 12h and 24h; against S5, reduction was 45.1% at 12h and up to 85.0% at 24h; and against S6, reduction was 91.8% at 12h, but due to regrowth of 52.9% at 24h. Cefditoren physiological concentrations exerted antibacterial activity against strains exhibiting MICs of 0.25 and 0.5 µg/ml under protein binding conditions similar to those in humans.

Conclusions/Significance

The results of this study suggest that, from the pharmacodynamic perspective, the presence of physiological albumin concentrations may not preclude antipneumococcal activity of highly bound cephalosporins as cefditoren.     

The PNPLA3 rs738409 148M/M genotype is a risk factor for liver cancer in alcoholic cirrhosis but shows no or weak association in hepatitis C cirrhosis

Background

An isoleucine>methionine mutation at position 148 in the PNPLA3 gene (p.I148M, rs738409) has recently been identified as a susceptibility factor for liver damage in steatohepatitis. Here, we studied whether the PNPLA3 rs738409 polymorphism also affects predisposition to hepatocellular carcinoma (HCC).

Methods

We compared distributions of PNPLA3 genotypes in 80 and 81 Caucasian patients with alcoholic and hepatitis C virus (HCV)-associated HCC to 80 and 81 age- and sex-matched patients with alcohol-related and HCV-related cirrhosis without HCC, respectively. PNPLA3 genotypes in 190 healthy individuals from the same population served as reference. Potential confounders obesity, diabetes, HCV genotype and HBV co-infection were controlled by univariate and multivariate logistic regression with forward variable selection.

Results

PNPLA3 genotypes were in Hardy-Weinberg equilibrium for all study groups. The frequency of the 148M allele was significantly (p<0.001) increased in alcoholic cirrhosis with (53.7%) and without HCC (36.2%) but was not different between healthy controls (22.9%) and patients with cirrhosis (25.3%; p = 0.545) and HCC (30.2%; p = 0.071) due to hepatitis C. HCC risk was highest in 148M/M homozygous patients with alcoholic liver disease (odds ratio (OR) 16.8 versus healthy controls; 95% confidence interval (CI) 6.68–42.43, p<0.001). Finally, multivariate regression confirmed 148M/M homozygosity (OR 2.8; 95%-CI: 1.24–6.42; p = 0.013) as HCC risk factor in alcoholic cirrhosis. In HCV-related cirrhosis only HCV genotype 1 was confirmed as a HCC risk factor (OR 4.2; 95%-CI: 1.50–11.52; p = 0.006).

Conclusion

The PNPLA3 148M variant is a prominent risk factor for HCC in patients with alcoholic cirrhosis, while its effects are negligible in patients with cirrhosis due to HCV. This polymorphism provides an useful tool to identify individuals with particularly high HCC risk in patients with alcoholic liver disease that should be taken into account in future HCC prevention studies.     

Functional Analysis of Two PLA2G2A Variants Associated with Secretory Phospholipase A2-IIA Levels

Background

Secretory phospholipase A2 group IIA (sPLA2-IIA) has been identified as a biomarker of atherosclerosis in observational and animal studies. The protein is encoded by the PLA2G2A gene and the aim of this study was to test the functionality of two PLA2G2A non-coding SNPs, rs11573156 C>G and rs3767221 T>G where the rare alleles have been previously associated with higher and lower sPLA2-IIA levels respectively.

Methodology/Principal Findings

Luciferase assays, electrophoretic mobility shift assays (EMSA), and RNA expression by RT-PCR were used to examine allelic differences. For rs3767221 the G allele showed ∼55% lower luciferase activity compared to the T allele (T = 62.1 (95% CI 59.1 to 65.1) G = 27.8 (95% CI 25.0 to 30.6), p = 1.22×10⁻³⁵, and stronger EMSA binding of a nuclear protein compared to the T-allele. For rs11573156 C >G there were no luciferase or EMSA allelic differences seen. In lymphocyte cell RNA, from individuals of known rs11573156 genotype, there was no allelic RNA expression difference for exons 5 and 6, but G allele carriers (n = 7) showed a trend to lower exon 1–2 expression compared to CC individuals. To take this further, in the ASAP study (n = 223), an rs11573156 proxy (r² = 0.91) showed ∼25% higher liver expression of PLA2G2A (1.67×10⁻¹⁷) associated with the G allele. However, considering exon specific expression, the association was greatly reduced for exon 2 (4.5×10⁻⁵) compared to exons 3–6 (10⁻¹⁰ to 10⁻²⁰), suggesting rs11573156 G allele-specific exon 2 skipping.

Conclusion

Both SNPs are functional and provide useful tools for Mendelian Randomisation to determine whether the relationship between sPLA2-IIA and coronary heart disease is causal.     

Genetic variations in plasma circulating DNA of HBV-related hepatocellular carcinoma patients predict recurrence after liver transplantation

Background

Recurrence prediction of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) patients undergoing liver transplantation (LT) present a great challenge because of a lack of biomarkers. Genetic variations play an important role in tumor development and metastasis.

Methods

Oligonucleotide microarrays were used to evaluate the genetic characteristics of tumor DNA in 30 HBV-related HCC patients who were underwent LT. Recurrence-related single-nucleotide polymorphism were selected, and their prognostic value was assessed and validated in two independent cohorts of HCC patients (N = 102 and N = 77), using pretransplant plasma circulating DNA. Prognostic significance was assessed by Kaplan-Meier survival estimates and log-rank tests. Multivariate analyses were performed to evaluate prognosis-related factors.

Results

rs894151 and rs12438080 were significantly associated with recurrence (P = .003 and P = .004, respectively). Multivariate analyses demonstrated that the co-index of the 2 SNPs was an independent prognostic factor for recurrence (P = .040). Similar results were obtained in the third cohort (N = 77). Furthermore, for HCC patients (all the 3 cohorts) exceeding Milan criteria, the co-index was a prognostic factor for recurrence and survival (P<.001 and P = .002, respectively).

Conclusions

Our study demonstrated first that genetic variations of rs894151 and rs12438080 in pretransplant plasma circulating DNA are promising prognostic markers for tumor recurrence in HCC patients undergoing LT and identify a subgroup of patients who, despite having HCC exceeding Milan criteria, have a low risk of post-transplant recurrence.     

Interactions of the apolipoprotein A5 gene polymorphisms and alcohol consumption on serum lipid levels

Background

Little is known about the interactions of apolipoprotein (Apo) A5 gene polymorphisms and alcohol consumption on serum lipid profiles. The present study was undertaken to detect the interactions of ApoA5–1131T>C, c.553G>T and c.457G>A polymorphisms and alcohol consumption on serum lipid levels.

Methodology/Principal Findings

A total of 516 nondrinkers and 514 drinkers were randomly selected from our previous stratified randomized cluster samples. Genotyping was performed by polymerase chain reaction and restriction fragment length polymorphism. The levels of serum total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), ApoA1 and ApoB were higher in drinkers than in nondrinkers (P<0.05–0.001). The genotypic and allelic frequencies of three loci were not different between the two groups. The interactions between –1131T>C genotypes and alcohol consumption on ApoB levels (P<0.05) and the ApoA1/ApoB ratio (P<0.01), between c.553G>T genotypes and alcohol consumption on low-density lipoprotein cholesterol (LDL-C) levels (P<0.05) and the ApoA1/ApoB ratio (P<0.05), and between c.457G>A genotypes and alcohol consumption on TG levels (P<0.001) were detected by factorial regression analysis after controlling for potential confounders. Four haplotypes (T-G-G, C-G-G, T-A-G and C-G-T) had frequencies ranging from 0.06 to 0.87. Three haplotypes (C-G-G, T-A-G, and C-G-T) were significantly associated with serum lipid parameters. The –1131T>C genotypes were correlated with TG, and c.553G>T and c.457G>A genotypes were associated with HDL-C levels in nondrinkers (P<0.05 for all). For drinkers, the –1131T>C genotypes were correlated with TC, TG, LDL-C, ApoB levels and the ApoA1/ApoB ratio (P<0.01 for all); c.553G>T genotypes were correlated with TC, TG, HDL-C and LDL-C levels (P<0.05–0.01); and c.457G>A genotypes were associated with TG, LDL-C, ApoA1 and ApoB levels (P<0.05–0.01).

Conclusions

The differences in some serum lipid parameters between the drinkers and nondrinkers might partly result from different interactions of the ApoA5 gene polymorphisms and alcohol consumption.     

Impact of genetic variation in SORCS1 on memory retention

Objective

We previously reported that genetic variants in SORCS1 increase the risk of AD, that over-expression of SorCS1 reduces γ-secretase activity and Aβ levels, and that SorCS1 suppression increases γ-secretase processing of APP and Aβ levels. We now explored the effect of variation in SORCS1 on memory.

Methods

We explored associations between SORCS1-SNPs and memory retention in the NIA-LOAD case control dataset (162 cases,670 controls) and a cohort of Caribbean Hispanics (549 cases,544 controls) using single marker and haplotype analyses.

Results

Three SNPs in intron 1, were associated with memory retention in the NIA-LOAD dataset or the Caribbean Hispanic dataset (rs10884402(A allele:β = −0.15,p = 0.008), rs7078098(C allele:β = 0.18,p = 0.007) and rs950809(C allele:β = 0.17,p = 0.008)) and all three SNPs were significant in a meta-analysis of both datasets (0.002ConclusionsVariation in intron 1 in SORCS1 is associated with memory changes in AD.     

A genetic variant in long non-coding RNA HULC contributes to risk of HBV-related hepatocellular carcinoma in a Chinese population

Background

Recently, several studies have demonstrated that two long non-coding RNAs (lncRNAs), HULC and MALAT1, may participate in hepatocellular carcinoma (HCC) development and progression. However, genetic variations in the two lncRNAs and their associations with HCC susceptibility have not been reported. In this study, we hypothesized that single nucleotide polymorphisms (SNPs) in HULC and MALAT1 may contribute to HCC risk.

Methods

We conducted a case-control study and genotyped two SNPs, rs7763881 in HULC and rs619586 in MALAT1, in 1300 HBV positive HCC patients, 1344 HBV persistent carriers and 1344 subjects with HBV natural clearance to test the associations between the two SNPs and susceptibility to HCC and HBV chronic infection.

Results

The variant genotypes of rs7763881 were significantly associated with decreased HCC risk in a dominant genetic model [AC/CC vs. AA: adjusted odds ration (OR)  =  0.81, 95% confidence intervals (CIs)  =  0.68–0.97, P  =  0.022]. Furthermore, the variant genotypes of rs619586 was associated with decreased HCC risk with a borderline significance (AG/GG vs. AA: adjusted OR  =  0.81, 95% CIs  =  0.65–1.01, P  =  0.057). However, no significant association was found between the two SNPs and HBV clearance.

Conclusions

The variant genotypes of rs7763881 in HULC may contribute to decreased susceptibility to HCC in HBV persistent carriers.     

Nucleotide sequence variation within the PI3K p85 alpha gene associates with alcohol risk drinking behaviour in adolescents

Background

While the phosphatidylinositol 3-kinase (PI3K)-dependent signaling pathway is typically known to regulate cell growth and survival, emerging evidence suggest a role for this pathway in regulating the behavioural responses to addictive drugs.

Methodology/Principal Findings

To investigate whether PI3K contributes to patterns of risky alcohol drinking in human, we investigated genetic variations in PIK3R1, encoding the 85 kD regulatory subunit of PIK, in 145 family trios consisting of 15–16 year old adolescents and their parents. Screening for mutations in exons, exon-intron boundaries and regulatory sequences, we identified 14 single nucleotide polymorphisms (SNPs) in the PIK3R1 gene region from exon 1 to the beginning of the 3′ untranslated region (UTR). These SNPs defined haplotypes for the respective PIK3R1 region. Four haplotype tagging (ht)SNPs (rs706713, rs2302975, rs171649 and rs1043526), discriminating all haplotypes with a frequency ≥4.5% were identified. These htSNPs were used to genotype adolescents from the “Mannheim Study of Risk Children” (MARC). Transmission disequilibrium tests in these adolescents and their parents demonstrated sex-specific association of two SNPs, rs2302975 and rs1043526, with patterns of risky alcohol consumption in male adolescents, including lifetime prevalence of drunkenness (p = 0.0019 and 0.0379, respectively) and elevated maximum amount of drinking (p = 0.0020 and 0.0494, respectively), as a measure for binge drinking pattern.

Conclusions/Significance

Our findings highlight a previously unknown relevance of PIK3R1 genotypes for alcohol use disorders and might help discriminate individuals at risk for alcoholism.     

Antibody dynamics of 2009 influenza A (H1N1) virus in infected patients and vaccinated people in China

Background

To evaluate the risk of the recurrence and the efficiency of the vaccination, we followed-up antibody responses in patients with the 2009 pandemic H1N1 influenza and persons who received the pandemic H1N1 vaccine in Guangzhou China.

Methods

We collected serum samples from 129 patients and 86 vaccinated persons at day 0, 15, 30, 180 after the disease onset or the vaccination, respectively. Antibody titers in these serum samples were determined by haemagglutination inhibition (HI) assay using a local isolated virus strain A/Guangdong Liwan/SWL1538/2009(H1N1).

Results

HI antibody positive rate of the patients increased significantly from 0% to 60% at day 15 (χ² = 78, P<0.001) and 100% at day 30 (χ² = 23, P<0.001), but decreased significantly to 52% at day 180 (χ² = 38, P<0.001), while that of vaccinated subjects increased from 0% to 78% at day 15 (χ² = 110, P<0.001) and 81% at day 30 (χ² = 0.32, P = 0.57), but decreased significantly to 34% at day 180 (χ² = 39, P<0.001). Geometric mean titers (GMT) of HI antibodies in positive samples from the patients did not change significantly between day 15 and day 30 (T = 0.92, P = 0.36), but it decreased significantly from 80 at day 30 to 52 at day 180 (T = 4.5, P<0.001). GMT of vaccinated persons increased significantly from 100 at day 15 to 193 at day 30 (T = 4.5, P<0.001), but deceased significantly to 74 at day 180 (T = 5.1, P<0.001). Compared to the patients, the vaccinated subjects showed lower seroconversion rate (χ² = 11, P<0.001; χ² = 5.9, P = 0.015), but higher GMT (T = 6.0, P<0.001; T = 3.6, P = 0.001) at day 30 and day 180, respectively.

Conclusion

Vaccination of 2009 influenza A (H1N1) was effective. However, about half or more recovered patients and vaccinated persons might have lost sufficient immunity against the recurrence of the viral infection after half a year. Vaccination or re-vaccination may be necessary for prevention of the recurrence.     

Tumor suppression by RNA from C/EBPβ 3'UTR through the inhibition of protein kinase Cε activity

Background

Since the end of last century, RNAs from the 3′untranslated region (3′UTR) of several eukaryotic mRNAs have been found to exert tumor suppression activity when introduced into malignant cells independent of their whole mRNAs. In this study, we sought to determine the molecular mechanism of the tumor suppression activity of a short RNA from 3′UTR of C/EBPβ mRΝΑ (C/EBPβ 3′UTR RNA) in human hepatocarcinoma cells SMMC-7721.

Methodology/Principal Findings

By using Western blotting, immunocytochemistry, molecular beacon, confocal microscopy, protein kinase inhibitors and in vitro kinase assays, we found that, in the C/EBPβ 3′UTR-transfectant cells of SMMC-7721, the overexpressed C/EBPβ 3′UTR RNA induced reorganization of keratin 18 by binding to this keratin; that the C/EBPβ 3′UTR RNA also reduced phosphorylation and expression of keratin 18; and that the enzyme responsible for phosphorylating keratin 18 is protein kinase Cε. We then found that the C/EBPβ 3′UTR RNA directly inhibited the phosphorylating activity of protein kinase Cε; and that C/EBPβ 3′UTR RNA specifically bound with the protein kinase Cε-keratin 18 conjugate.

Conclusion/Significance

Together, these facts suggest that the tumor suppression in SMMC-7721 by C/EBPβ 3′UTR RNA is due to the inhibition of protein kinase Cε activity through direct physical interaction between C/EBPβ 3′UTR RNA and protein kinase Cε. These facts indicate that the 3′UTR of some eukaryotic mRNAs may function as regulators for genes other than their own.     

Genetic Variants of LDLR and PCSK9 Associated with Variations in Response to Antihypercholesterolemic Effects of Armolipid Plus with Berberine

Background

Armolipid Plus (AP) is a nutraceutical that contains policosanol, fermented rice with red yeast, berberine, coenzyme Q10, folic acid, and astaxanthin. It has been shown to be effective in reducing plasma LDL cholesterol (LDLc) levels. In the multicenter randomized trial {"type":"clinical-trial","attrs":{"text":"NCT01562080","term_id":"NCT01562080"}}NCT01562080, there was large interindividual variability in the plasma LDLc response to AP supplementation. We hypothesized that the variability in LDLc response to AP supplementation may be linked to LDLR and PCSK9 polymorphisms.

Material and Methods

We sequenced the LDLR 3′ and 5′ untranslated regions (UTR) and the PCSK9 5′ UTR of 102 participants with moderate hypercholesterolemia in trial {"type":"clinical-trial","attrs":{"text":"NCT01562080","term_id":"NCT01562080"}}NCT01562080. In this trial, 50 individuals were treated with AP supplementation and the rest with placebo.

Results

Multiple linear regression analysis, using the response of LDLc levels to AP as the dependent variable, revealed that polymorphisms rs2149041 (c.-3383C>G) in the PCSK9 5′ UTR and rs14158 (c.*52G>A) in the LDLR 3′ UTR explained 14.1% and 6.4%, respectively, of the variability after adjusting for gender, age, and BMI of individuals. Combining polymorphisms rs2149041 and rs14158 explained 20.5% of this variability (p < 0.004).

Conclusions

Three polymorphisms in the 3′ UTR region of LDLR, c.*52G>A, c.*504G>A, and c.*773A>G, and two at the 5′ UTR region of PCSK9, c.−3383C>G and c.−2063A>G, were associated with response to AP. These results could explain the variability observed in the response to berberine among people with moderate hypercholesterolemia, and they may be useful in identifying patients who could potentially benefit from supplementation with AP.