Sex difference in 5-year relative survival following percutaneous coronary intervention

Background

Sex-specific survival following percutaneous coronary intervention (PCI) varies among studies. This might be clarified using relative survival, which adjusts observed survival in relation to that seen in sex- and age-matched general population. We investigated sex-specific relative survival after PCI.

Methods

A total of 48,783 patients were enrolled in the year 2011 Korean nationwide PCI cohort. Primary outcome was all-cause death. Observed and relative survival at 5 years conditional on surviving 0 days, 30 days, 1 year, and 2 years were assessed. Sex-specific differences in cardiovascular risk factors were adjusted via age-group stratified propensity score matching.

Results

In the unadjusted analyses, 15,710 female patients had a higher frequency of cardiovascular risk factors compared with 33,073 male patients. Both observed survival (hazard ratio [HR]=1.28, 95% confidence interval [CI]=1.22–1.34) and relative survival (HR=1.21, 95% CI: 1.16–1.27) were worse in female compared with male (p<0.001, all). In analyses of propensity score-matched 14,454 pairs, female showed a higher observed survival (HR=0.78, 95% CI: 0.74–0.82) but a lower relative survival (HR=1.19, 95% CI: 1.13–1.26) compared with male (p<0.001, all). Neither observed nor relative survival differed between female of age≤50s and age-matched male, but they were lower in female of age≥60s than age-matched male. These findings were consistent in further analyses conditional on surviving 30 days, 1 year, and 2 years.

Conclusions

The 5-year relative survival of female aged≥60 years adjusted by clinical risk factors was lower than that of age-matched male, which mandates the need for the excessive risk reduction in older female undergoing PCI.

Funding Acknowledgement

Type of funding sources: None.

Hyperaemic and non-hyperaemic pressure indices of coronary stenosis severity in patients with chronic kidney disease

Background

Evidence regarding the use of pressure indices for the assessment of coronary stenoses in patients with chronic kidney disease (CKD) is scarce.

Methods

We assessed the relation between eGFR, FFR and resting Pd/Pa in 1147 consecutive patients (1316 vessels) included in the International Collaboration of Comprehensive Physiologic Assessment Study. We also compared FFR and Pd/Pa against a standardized cut-off of coronary flow reserve (CFR<2.0). Finally, we examined the occurrence of vessel-oriented composite outcome (VOCO: cardiac death, vessel-specific revascularization, vessel-specific myocardial infarction) across negative/positive results of both FFR and CFR in patients with and without CKD.

Results

FFR increases as renal function worsens (beta −10.5, 95% CI −20.0 to −11.03, p=0.030), a relation that was not seen with resting Pd/Pa (beta −6.14, 95% CI −19.9 to 6.78, p=0.351). Both indices had similar diagnostic accuracies for the detection of a CFR<2.0 in the presence of CKD (AUC 0.629 for FFR vs 0.663 for resting Pd/Pa, p=0.192). However, CKD patients showed a higher proportion of vessels with negative FFR but low CFR (24.5% vs 13.4%, p=0.015).

CFR decreased linearly with deteriorating eGFR, and this was mainly driven by higher resting coronary flow in CKD patients (p=0.026), while hyperaemic coronary flow remained similar (p=0.403). IMR did not change significantly with eGFR (beta −0.02, 95% −0.09 to 0.05, p=0.557).

The incidence of VOCO was higher in patients with CKD and FFR>0.80 when compared to non-CKD patients and FFR>0.80 (12.7% vs 6.90%, p=0.062). Prognosis was worse for those with CKD, negative FFR and CFR<2.0 (20.59% vs. 8.44% in non-CKD, p=0.038).

Conclusions

The assessment of a given coronary stenosis in patients with CKD with either FFR or resting Pd/Pa is equivalent when compared to underlying coronary flow. In CKD, impaired CFR is caused by a state of increased resting flow. The assessment of CFR on top of standard pressure wire examination significantly improves prognostic stratification in CKD patients.

Funding Acknowledgement

Type of funding sources: None.

Aspirin vs. Clopidogrel as a Chronic maintenance monotherapy after PCI in patients with high ischemic risk and high bleeding risk: Subgroup analysis of the HOST-EXAM trial

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

on behalf of the HOST-EXAM investigators

Background

The HOST-EXAM randomized clinical trial recently performed a comparison of clopidogrel monotherapy vs. aspirin monotherapy in patients requiring indefinite antiplatelet monotherapy after percutaneous coronary intervention (PCI). This study randomized 5,438 patients who maintained dual antiplatelet therapy without clinical events for 6–18 months after PCI with drug-eluting stents (DES) to receive a monotherapy agent of clopidogrel 75 mg once daily or aspirin 100 mg once daily for 24 months. During the 24-month follow-up, the primary outcome (a composite of all-cause death, non-fatal myocardial infarction, stroke, readmission due to acute coronary syndrome, and Bleeding Academic Research Consortium (BARC) bleeding type 3 or greater) rate was significantly lower in the clopidogrel group (hazard ratio [HR] 0.73 [95% CI 0.59–0.90]; p = 0.0035). However, it is uncertain whether the beneficial effect of clopidogrel will be consistent in patients with high ischemic risk or those with high bleeding risk.

Methods

This is a post-hoc analysis of the HOST-EXAM trial. A high ischemic risk was defined as those who had at least 1 of the following procedural features: 3 vessels treated, ≥3 stents implanted, ≥3 lesions treated, bifurcation PCI, total stent length >60 mm, or left main PCI. Patients with high bleeding risk were defined according to the Academic Research Consortium for High Bleeding Risk (ARC-HBR) criteria. The co-primary outcome were thrombotic endpoints (a composite of cardiac death, non-fatal myocardial infarction, ischemic stroke, readmission due to acute coronary syndrome, and definite or probable stent thrombosis) and bleeding endpoints (BARC type ≥2 bleeding events) at 24-month follow-up.

Results

 Among the total population, 22.1% had high ischemic risk and 21.4% had high bleeding risk. Complex PCI was not associated with a higher risk of thrombotic endpoints, nor bleeding endpoints. For patients with a high bleeding risk, these patients had a higher risk of both thrombotic endpoints (HR 1.545, 95% CI 0.141-2.092, p = 0.005) and bleeding endpoints (HR 3.418, 95% CI 2.413-4.840, p < 0.001). The primary results focusing on the interaction between high ischemic risk, high bleeding and the antiplatelet regimen will be presented.

Conclusion

The current post-hoc analysis of the HOST-EXAM trial will evaluate the efficacy of clopidogrel monotherapy vs. aspirin monotherapy during the chronic maintenance period after PCI, in patients with high ischemic risk or those with high bleeding risk.

Genome-wide association study of right-sided colonic diverticulosis in a Korean population

Diverticulosis results from complex interactions related to aging, environmental factors and genetic predisposition. Despite epidemiologic evidence of genetic risk factors, there has been no attempt to identify genes that confer susceptibility to colonic diverticulosis. We performed the first genome-wide association study (GWAS) on susceptibility to diverticulosis in a Korean population. A GWAS was carried out in 7,948 healthy individuals: 893 patients and 1,075 controls comprised the test set, and 346 patients and 305 controls comprised the replication set. Diverticulosis was diagnosed by colonoscopy during comprehensive medical check-ups, and single-nucleotide polymorphisms (SNPs) related to diverticulosis were detected with the Affymetrix Axiom KORV1.1-96 Array. In all, 9 SNPs were identified in three SNP aggregates in the test set (P < 10⁻³, within 200 kb) after adjusting for sex. All the SNPs were replicated in the replication set (P < 0.05). Three SNPs were near the WNT4 gene, four near the RHOU gene, and two in the OAS1/3 genes. The top SNP associated with right-sided colonic diverticulosis was rs22538787, located near the WNT4 gene [combined set, P-value = 3.128 × 10⁻⁶, odds ratio = 1.415 (95% confidence interval: 1.223–1.637)]. These 9 novel SNP alleles associated with the WNT4, RHOU, and OAS1/3 genes are possibly involved in the underlying genetic susceptibility to right-sided diverticulosis. Our results provide basic knowledge about the development of diverticulosis in an Asian population.

Genome-Wide Analysis Reveals Four Novel Loci for Attention-Deficit Hyperactivity Disorder in Korean Youths

Objectives:

The molecular mechanisms underlying attention-deficit hyperactivity disorder (ADHD) remain unclear. Therefore, this study aimed to identify the genetic susceptibility loci for ADHD in Korean children with ADHD. We performed a case-control and a family-based genome-wide association study (GWAS), as well as genome-wide quantitative trait locus (QTL) analyses, for two symptom traits.

Methods:

A total of 135 subjects (71 cases and 64 controls), for the case-control analysis, and 54 subjects (27 probands and 27 unaffected siblings), for the family-based analysis, were included.

Results:

The genome-wide QTL analysis identified four single nucleotide polymorphisms (SNPs) (rs7684645 near APELA, rs12538843 near YAE1D1 and POU6F2, rs11074258 near MCTP2, and rs34396552 near CIDEA) that were significantly associated with the number of inattention symptoms in ADHD. These SNPs showed possible association with ADHD in the family-based GWAS, and with hyperactivity-impulsivity in genome-wide QTL analyses. Moreover, association signals in the family-based QTL analysis for the number of inattention symptoms were clustered near genes IL10, IL19, SCL5A9, and SKINTL.

Conclusion:

We have identified four QTLs with genome-wide significance and several promising candidates that could potentially be associated with ADHD (CXCR4, UPF1, SETD5, NALCN-AS1, ERC1, SOX2-OT, FGFR2, ANO4, and TBL1XR1). Further replication studies with larger sample sizes are needed.

Association between Polymorphisms in Bitter Taste Receptor Genes and Clinical Features in Korean Asthmatics

BACKGROUND

Bitter taste receptors (TAS2R) in human airway smooth muscle have recently been shown to have an important role in bronchodilation, together with β2-adrenergic receptors.

OBJECT

To evaluate the association between genetic variations in TAS2R and clinical features, including bronchodilator response and asthma control.

METHOD

We analyzed the association between single nucleotide polymorphisms (SNPs) of TAS2R10 and TAS2R14 and variables such as demographic data, atopy, duration of disease, and asthma control status, including variables such as asthma control test (ACT) score, percent predicted value of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio, as well as bronchodilator response (BDR), in 721 asthma patients in Korea.

RESULT

Three novel SNPs of 633G>A, 645C>A, and -79G>A in TAS2R10 and 3 known SNPs of -815T>C, -1267G>A, and -1897T>C in TAS2R14 were analyzed. Increased BDR was significantly associated with SNPs of -815T>C [OR (95% CI) = 1.88 (1.01-3.49), p = 0.04 ] [J Gen Physiol 2005;125:535-553; Am J Respir Cell Mol Biol 2010;42:373-3812], -1267A>G [OR (95% CI) = 2.07 (1.03-4.15), p = 0.04] and -1897T>C [OR (95% CI) = 3.05 (1.01-9.23), p = 0.04, in a dominant model, and OR = 1.91 (1.08-3.36), p = 0.02, in a codominant model] of the TAS2R14 gene. There was a significant association between -815T>C and a low mean ACT score [OR (95% CI) = 5.84 (1.94-17.61), p = 0.001]. In haplotype analysis, TAC, CAT, and TGT, or TG and CA haplotypes on TAS2R14 were significantly associated with increased BDR; CAT and CA haplotypes were significantly associated with a low ACT score.

CONCLUSION

Genetic variations in TAS2Rs may be valuable genetic markers to predict therapeutic response and outcomes in asthma. Further research in an independent cohort is needed.

The SNP rs3128965 of HLA-DPB1 as a genetic marker of the AERD phenotype

BACKGROUND

Two common clinical syndromes of acetylsalicylic acid (aspirin) hypersensitivity, aspirin-exacerbated respiratory disease (AERD) and aspirin-exacerbated cutaneous disease (AECD), were subjected to a genome-wide association study to identify strong genetic markers for aspirin hypersensitivity in a Korean population.

METHODS

A comparison of SNP genotype frequencies on an Affymetrix Genome-Wide Human SNP array of 179 AERD patients and 1989 healthy normal control subjects (NC) revealed SNPs on chromosome 6 that were associated with AERD, but not AECD. To validate the association, we enrolled a second cohort comprising AERD (n = 264), NC (n = 238) and disease-control (aspirin tolerant asthma; ATA, n = 387) groups.

RESULTS

The minor genotype frequency (AG or AA) of a particular SNP, rs3128965, in the HLA-DPB1 region was higher in the AERD group compared to the ATA or NC group (P = 0.001, P = 0.002, in a co-dominant analysis model, respectively). Comparison of rs3128965 alleles with the clinical features of asthmatics revealed that patients harboring the A allele had increased bronchial hyperresponsiveness to inhaled aspirin and methacholine, and higher 15-HETE levels, than those without the A allele (P = 0.039, 0.037, and 0.004, respectively).

CONCLUSIONS

This implies the potential of rs3128965 as a genetic marker for diagnosis and prediction of the AERD phenotype.

Common and rare variants in the exons and regulatory regions of osteoporosis-related genes improve osteoporotic fracture risk prediction

CONTEXT

Osteoporotic fracture risk is highly heritable, but genome-wide association studies have explained only a small proportion of the heritability to date. Genetic data may improve prediction of fracture risk in osteopenic subjects and assist early intervention and management.

OBJECTIVE

To detect common and rare variants in coding and regulatory regions related to osteoporosis-related traits, and to investigate whether genetic profiling improves the prediction of fracture risk.

DESIGN AND SETTING

This cross-sectional study was conducted in three clinical units in Korea.

PARTICIPANTS

Postmenopausal women with extreme phenotypes (n = 982) were used for the discovery set, and 3895 participants were used for the replication set.

MAIN OUTCOME MEASURE

We performed targeted resequencing of 198 genes. Genetic risk scores from common variants (GRS-C) and from common and rare variants (GRS-T) were calculated.

RESULTS

Nineteen common variants in 17 genes (of the discovered 34 functional variants in 26 genes) and 31 rare variants in five genes (of the discovered 87 functional variants in 15 genes) were associated with one or more osteoporosis-related traits. Accuracy of fracture risk classification was improved in the osteopenic patients by adding GRS-C to fracture risk assessment models (6.8%; P < .001) and was further improved by adding GRS-T (9.6%; P < .001). GRS-C improved classification accuracy for vertebral and nonvertebral fractures by 7.3% (P = .005) and 3.0% (P = .091), and GRS-T further improved accuracy by 10.2% (P < .001) and 4.9% (P = .008), respectively.

CONCLUSIONS

Our results suggest that both common and rare functional variants may contribute to osteoporotic fracture and that adding genetic profiling data to current models could improve the prediction of fracture risk in an osteopenic individual.

Prognostic impact of telomere maintenance gene polymorphisms on hepatocellular carcinoma patients with chronic hepatitis B

Our goal was to determine whether single-nucleotide polymorphisms (SNPs) of telomere maintenance genes influence the development and clinical outcomes of patients with hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC). We evaluated 20 SNPs of five telomere maintenance genes in 702 patients with HCC and 351 hepatitis B virus surface antigen-positive controls without HCC. Significant SNPs were then validated in an independent cohort of 857 HCC patients and 429 controls. We assessed the association of each SNP with the development of HCC and overall survival through a multivariate Cox proportional analysis. A significantly increased risk of HCC development was identified for the telomerase-associated protein 1 (TEP1) rs1713449 SNP in both the discovery and replication phases (combined odds ratio = 1.42, P = 9.378 × 10(-5) ). In addition, the TEP1 rs1713449, TEP1 rs872072, protection of telomeres 1 homolog rs7784168, telomerase reverse transcriptase rs13167280, and telomeric repeat binding factor 1 rs2306494 SNPs had a significant effect on the overall survival, and a similar survival effect was validated in the replication cohort. Moreover, there was a significant dose-dependent association between the number of putatively high-risk genotypes of the five aforementioned SNPs and overall survival. The median survival time was significantly prolonged for patients with HCC with two or fewer putatively high-risk genotypes versus those with three or more high-risk genotypes (85 versus 44 months, log-rank P = 4.483 × 10(-5) ), and this was demonstrated in the replication cohort (52 versus 37 months, log-rank P = 0.026).

CONCLUSION

These observations suggest that the SNPs of telomere maintenance genes play a potential role in the development of HCC and the survival of HCC patients with chronic HBV infections.

The Interaction Between Allelic Variants of CD86 and CD40LG: A Common Risk Factor of Allergic Asthma and Rheumatoid Arthritis

PURPOSE

Allergic asthma (AA) and rheumatoid arthritis (RA) are immune tolerance-related diseases, and immune tolerance is known to be influenced by costimulatory molecules. In this study, we sought to identify common genetic susceptibility in AA and RA.

METHODS

Two hundred cases of AA, 184 cases of RA, and 182 healthy controls were recruited at the Seoul National University Hospital, Seoul, Korea. Eight single nucleotide polymorphisms (SNPs) in five genes coding costimulatory molecules, namely, -318C>T, +49A>G, and 6230G>A in CTLA4, IVS3+17T>C in CD28, -3479T>G and I179V in CD86, -1C>T in CD40, and -3458A>G in CD40LG were scored, and genetic interactions were evaluated by multifactor dimensionality reduction (MDR) analysis.

RESULTS

MDR analysis revealed a significant gene-gene interaction between -3479T>G CD86 and -3458A>G CD40LG for AA. Subjects with the T/T genotype of -3479T>G CD86 and the A/A genotype of -3458A>G CD40LG were found to be significantly more likely to develop AA than those with the T/T genotype of -3479T>G CD86 and A/- genotype of -3458A>G CD40LG (adjusted OR, 6.09; 95% CI, 2.89-12.98; logistic regression analysis controlled by age). Similarly those subjects showed a significant risk of developing RA (adjusted OR, 39.35; 95% CI, 15.01-107.00, logistic regression analysis controlled by age).

CONCLUSIONS

Our findings suggest that a genetic interaction between CD86 and CD40LG favors the development of both AA and RA.

STAT1-mediated Bim expression promotes the apoptosis of retinal pericytes under high glucose conditions

Hyperglycemia impacts different vascular cell functions and promotes the development and progression of various vasculopathies including diabetic retinopathy. Although the increased rate of apoptosis in pericytes (PCs) has been linked to increased oxidative stress and activation of protein kinase C-δ (PKC-δ) and SHP-1 (Src homology region 2 domain-containing phosphatase-1) tyrosine phosphatase during diabetes, the detailed mechanisms require further elucidation. Here we show that the rate of apoptosis and expression of proapoptotic protein Bim were increased in the retinal PCs of diabetic Akita/+ mice and mouse retinal PCs cultured under high glucose conditions. Increased Bim expression in retinal PCs under high glucose conditions required the sustained activation of signal transducer and activator of transcription 1 (STAT1) through production of inflammatory cytokines. PCs cultured under high glucose conditions also exhibited increased oxidative stress and diminished migration. Inhibition of oxidative stress, PKC-δ or Rho-associated protein kinase I/II was sufficient to protect PCs against apoptosis under high glucose conditions. Furthermore, PCs deficient in Bim expression were protected from high glucose-mediated increased oxidative stress and apoptosis. However, only inhibition of PKC-δ lowered Bim levels. N-acetylcysteine did not affect STAT1 levels, suggesting that oxidative stress is downstream of Bim. PCs cultured under high glucose conditions disrupted capillary morphogenesis of retinal endothelial cells (ECs) in coculture experiments. In addition, conditioned medium prepared from PCs under high glucose conditions attenuated EC migration. Taken together, our results indicate that Bim has a pivotal role in the dysfunction of retinal PCs under high glucose conditions by increasing oxidative stress and death of PCs.

Genetic variants in the IL12B gene are associated with inflammatory bowel diseases in the Korean population

BACKGROUND AND AIM

Recent genomic studies have identified genetic variants in the IL12B gene, which encodes the p40 subunit shared by interleukin 12 and interleukin 23, as susceptibility loci for inflammatory bowel disease (IBD). The study aimed to identify additional novel genetic variants in IL12B and investigated whether variants confer susceptibility to the development of Crohn's disease (CD) or ulcerative colitis (UC) in the Korean population.

METHODS

To detect single nucleotide polymorphisms (SNPs) in IL12B, direct sequencing of all coding exons, exon-intron boundaries, promoter region, and 5' untranslated region was performed in 24 randomly selected samples. Selected haplotype-tagging SNPs were subsequently genotyped in 493 IBD patients (245 patients with CD and 248 with UC) and 504 healthy controls.

RESULTS

Two haplotype-tagging SNPs (rs2288831 and rs919766) were selected through direct sequencing and were genotyped. Of them, SNP rs2288831 in the IL12B gene was significantly associated with CD susceptibility in allelic association analysis (odds ratio = 1.30; 95% confidence interval 1.04-1.62; P = 0.019). This significant association with CD was also observed for a haplotype consisting of SNP rs919766 and rs2288831 (odds ratio = 1.29; 95% confidence interval 1.03-1.60; P = 0.025). However, none of IL12B SNPs were associated with UC susceptibility. Finally, no specific associations between genetic variants and disease phenotype of CD were identified.

CONCLUSIONS

This study is first to identify SNP rs2288831 in the IL12B gene as a susceptible variation for CD. Further studies in other ethnic groups are warranted to validate the association of this genetic variant with IBD.

Lack of association of genetic variations of deoxycytidine kinase with toxicity or survival of non-small-cell lung cancer patients treated with gemcitabine plus cisplatin

The aim of this study was to determine whether tagging polymorphisms (tSNPs) of deoxycytidine kinase (DCK) have an effect on toxicity or prognosis in patients with non-small-cell lung cancer (NSCLC) treated with gemcitabine plus cisplatin. Three tSNPs (-201 C>T, rs2306744; IVS2+9846 G>A, rs12648166; IVS6+1392 T>C, rs4694362) were chosen using the international HapMap Project and Japanese Single-Nucleotide Polymorphisms. We evaluated the associations of the tSNPs with hematologic toxicity or overall survival of 139 NSCLC patients at stages IIIA/IIIB (59) and IV (80). Hematologic toxicity such as neutropenia, thrombocytopenia, and anemia were not different by the three tSNPs or haplotypes (CGT, CAT, and CAC) of DCK. The genetic variations did not affect survival of the patients (log-rank p: 0.248 for -201 C>T, 0.571 for IVS2+9846 G>A, 0.686 for IVS6+1392 T>C, 0.556 for CGT, 0.453 for CAT, and 0.845 for CAC). In a Cox model, these tSNPs and haplotypes did not reveal prognostic relevance (aHR and 95% CI: 0.954 and 0.611 to 1.489 for -201 C>T; 1.193 and 0.719 to 1.979 for IVS2+9846 G>A; 1.072 and 0.674 to 1.706 for IVS6+1392 T>C, 0,668 and 0.205 to 2.175 for CGT, 1.043 and 0.713 to 1.525 for CAT, and 1.043 and 0.701 to 1.550 for CAC). This is the first study to focus on the association of tSNPs and their haplotypes of DCK with toxicity and survival in NSCLC patients. This suggests that genetic variations of DCK have no effect on the outcomes in the patients treated with gemcitabine-based chemotherapy.

Association of CYP2C19*2 and *3 genetic variants with essential hypertension in Koreans

PURPOSE

The cytochrome P450 2C19 (CYP2C19) metabolizes arachidonic acid to produce epoxyicosanoid acids, which are involved in vascular tone and regulation of blood pressure. Recent findings suggest that CYP2C19 gene might be considered as a novel candidate gene for treatment of cardiovascular disease. The aim of the present study was to evaluate the association between two variants, CYP2C19* 2 (681G>A) and CYP2C19*3 (636G>A) and the development of essential hypertension (EH) in Koreans.

MATERIALS AND METHODS

We carried out an association study in a total of 1190 individuals (527 hypertensive subjects and 663 unrelated healthy controls). The CYP2C19 polymorphisms were genotyped using the SNaPShot™ assay.

RESULTS

The distribution of alleles and genotypes of CYP2C19* 3 showed significant difference between hypertensive patients and normal controls (p=0.011 and p=0.013, respectively). Logistic regression analysis indicated that the CYP2C19*3 (636A) allele carriers were significantly associated with EH [odds ratio, 0.691; 95% confidence interval (CI), 0.512-0.932, p=0.016], in comparison to wild type homozygotes (CYP2C19*1/*1). Neither genotype nor allele distribution of CYP2C19*2 polymorphism showed significant differences between hypertensive and control groups (p>0.05).

CONCLUSION

Our present findings strengthen the evidence of an association between CYP2C19 gene polymorphism and EH prevalence. In particular, the CYP2C19*3 defective allele may contribute to reduced risk for the development of EH.

Genetic predisposition of hand-foot skin reaction after sorafenib therapy in patients with hepatocellular carcinoma

BACKGROUND

Sorafenib currently sets the new standard for advanced hepatocellular carcinoma (HCC). It has been suggested that Asian patients with HCC have increased susceptibility to hand-foot skin reaction (HFSR) related to sorafenib therapy. The authors investigated the association between sorafenib-induced HFSR and genetic polymorphisms in Korean patients with HCC.

METHODS

For this prospective cohort study, the authors enrolled 59 consecutive patients with intermediate stage HCC from 5 centers in Korea. All patients received sorafenib 400 mg twice daily in combination with transarterial chemoembolization (TACE). Genotyping was performed on a total of 49 single nucleotide polymorphisms (SNPs) in 8 candidate genes (minor allelic frequency ≥5%). Serum levels of vascular endothelial growth factor (VEGF) and tumor necrosis factor-alpha (TNF-α) were measured using enzyme-linked immunosorbent assays before therapy and 1 month after therapy.

RESULTS

During a median treatment period of 18 months, 55 patients (93%) developed sorafenib-induced HFSR, including grade 1 reactions in 15 patients, grade 2 reactions in 27 patients, and grade 3 reaction in 13 patients. The SNPs TNF-α -308GG, VEGF -94GG, VEGF 1991CC, VEGF IVS3-28CC, and uridine diphosphate glucuronosyltransferase 1 family-polypeptide A9 (UGT1A9) IVS1-37431AA were associated significantly with the development of high-grade (grade 2 or 3) HFSR in univariate analysis (P < .05). In multivariate analysis, the SNPs VEGF 1991CC (odds ratio, 45.7), TNF-α -308GG (odds ratio, 44.1), and UGT1A9 IVS1-37431AA (odds ratio, 18.7) were identified as independent risk factors for the development of high-grade HFSR (P = .01, P = .02, and P = .02, respectively). He serum TNF-α level measured 1 month after sorafenib therapy was correlated significantly with the development of high-grade HFSR (odds ratio, 3.56; P = .026).

CONCLUSIONS

Differences in the incidence of HFSR may have been caused by ethnic differences in genetic polymorphisms of the TNF-α, VEGF, and UGT1A9 genes, especially in relation to the expression of serum TNF-α after sorafenib therapy.

Single nucleotide polymorphisms associated with metastatic tumour antigen 1 overexpression in patients with hepatocellular carcinoma

BACKGROUNDS/AIMS

Metastatic tumour antigen 1 (MTA1) promotes angiogenesis by stabilizing hypoxia-inducible factor-1α (HIF-1α), which is closely associated with frequent postoperative recurrence and poor survival in patients with HCC. In this study, we determined single nucleotide polymorphisms (SNPs) in angiogenesis-related genes that are associated with MTA1 overexpression in HCC tissues.

METHODS

A total of 376 patients with HCC who had received curative surgical resection or liver transplantation were enrolled (312/21/43; HBV/HCV/NBNC). MTA1 expression was determined via immunohistochemistry. Thirty-three common SNPs sites (frequency ≥5%) in the angiogenic protein gene that are closely connected to one another were selected, including MTA1, VEGF, HIF-1α, FGF-2, and IGF-II.

RESULTS

Expression of MTA1 was detected in 120 HCC tissues (31%). An A allele at position IVS4-81G/A of the MTA1 gene (P = 0.016) and the TT genotype at position +12916C of the VEGF gene (P = 0.023) were significantly associated with MTA1 overexpression. However, the TT genotype at position -13021C (P = 0.011) and the haplotypes CT-CT (-11228C; -13021C) of the IGF-II gene (P(cor) = 0.033) were more common in patients with MTA1-negative HCC. Using multivariate analysis, the A allele at IVS4-81G/A in MTA1 gene (P = 0.015) and a T allele (TT+CT genotype) at -13021C in IGF-II (P = 0.002) were independent risk factors in HCC recurrence after curative surgical resection.

CONCLUSIONS

The genetic polymorphisms IVS4-81G/A in MTA1 and +12916C in VEGF genes were correlated with MTA1 overexpression. The SNPs in MTA1 and IGF-II genes may be important risk factors for the recurrence of HCC.

Genetic Variations in TXNRD1 as Potential Predictors of Drug-Induced Liver Injury

Purpose

Drug-induced liver injury (DILI) is the most common adverse drug reaction; however, it is not easily predicted. We hypothesize that DILI has a common genetic basis. Based on the findings of previous animal studies on toxic hepatitis, we selected the thioredoxin reductase 1 gene (TXNRD1) as a candidate marker of DILI for this genetic association study.

Methods

Records from 118 patients with DILI were extracted from the database of the Adverse Drug Reaction Research Group in South Korea. Causative drugs included antituberculosis drugs (n=68, 57.6%), antibiotics (n=22, 18.6%), antiepileptic drugs (n=7, 5.9%), non-steroidal anti-inflammatory drugs (n=5, 4.2%), and others (n=16, 13.7%). Seven single nucleotide polymorphisms (SNPs) in TXNRD1 (rs10735393, rs4964287, rs4595619, rs10861201, rs11111997, rs4246270, and rs4246271) were scored in 118 DILI patients and in 120 drug-matched controls without liver injury.

Results

No differences were found between the frequencies of any of the 7 SNPs in the cases and controls; however, a significant association was found between a TTA haplotype composed of rs10735393, rs4964287, and rs4595619 and DILI using an allele model (odds ratio, 1.79; 95% confidence interval, 1.18-2.73; P=0.008; Bonferroni corrected P=0.024).

Conclusions

These results suggest that genetic variations in TXNRD1 favor the development of DILI, although a larger confirmative study is needed.

Vitamin D Receptor Gene TaqI, BsmI and FokI Polymorphisms in Korean Patients with Tuberculosis

BACKGROUND

The active metabolite (1, 25-dihydroxycholecalciferol) of vitamin D (25-hydroxycholecalciferol) leads to activation of macrophages and deficiency of vitamin D seems to be involved in the risk of tuberculosis. The effects of vitamin D are exerted by interaction with the vitamin D receptor (VDR) and may be influenced by polymorphism in the VDR gene. In this study, variation in the VDR gene was investigated in Korean population with tuberculosis.

METHODS

We typed three VDR polymorphisms of restriction endonuclease sites for TaqI, BsmI and FokI in 155 patients with tuberculosis and 105 healthy volunteers.

RESULTS

The frequencies of FokI genotypes determined from TB patients were 29.13% for FF, 56.31% for Ff, and 14.56% for ff. We observed 1.4-fold increased prevalence of the Ff genotype in TB patients compared with normal healthy groups (p=0.0857). However, there was no significant association between the genotype groups, TB patient and normal control, for FokI polymorphism. There was also no significant association between VDR gene and tuberculosis in another polymorphism (BsmI and TaqI).

CONCLUSION

Three polymorphisms (TaqI, BsmI and FokI) in the VDR gene do not appear to be responsible for host susceptibility to human tuberculosis in Korean population.

Association of polymorphisms in genes encoding IL-4, IL-13 and their receptors with atopic dermatitis in a Korean population

Th2-dominated immune responses are believed to contribute to the pathogenesis of atopic dermatitis (AD). IL-4 and IL-13 are typical pleiotropic Th2 cytokines that play a central role in IgE-dependent inflammatory reactions. Single-nucleotide polymorphisms (SNPs) in IL-4 and IL-13 have been reported in patients with allergic disease from numerous countries. Gene-gene interactions among genes have been identified in patients with asthma, although negative results have been reported. To investigate the associations of SNPs in these genes and the interactions between these genes in AD, we genotyped 23 SNPs of the IL-4, IL-13, IL-4R, IL-13Rα1 and IL-13Rα2 genes for 1089 case-control samples (631 AD patients and 458 controls) and analysed the SNPs and haplotypes in these genes. We also searched for gene-gene interactions among these five genes. Our data identified an association between rs3091307 and rs20541 in the IL-13 gene and between rs2265753 and rs2254672 in the IL-13Rα1 gene and the AD phenotype. In particular, three of the four SNPs were especially predictive of the allergic type of AD (ADe), and the haplotype TCGG in the IL-13Rα1 gene showed significant association with AD, especially ADe. Furthermore, the combination of rs3091307 GG/ rs2265753 GG (IL-13/IL-13Rα1) conveyed a significantly higher risk for developing ADe. However, we did not identify any SNPs in the IL-4, IL-4R and IL-13Rα2 genes that were associated with AD. As IL-13Rα1 is most likely expressed in Th17 cells rather than in Th2 cells, these data suggest diversity in the classification of Th cells that needs to be verified in future studies.

A glycoprotein from Porphyra yezoensis produces anti-inflammatory effects in liposaccharide-stimulated macrophages via the TLR4 signaling pathway

The purpose of this study was to investigate the antioxidant and anti-inflammatory effects of a glycoprotein isolated from the alga Porphyra yezoensis in LPS-stimulated RAW 264.7 mouse macrophages. First, we extracted a novel material with antioxidant activity from P. yezoensis, confirmed by SDS-PAGE to be a glycoprotein, which we named P. yezoensis glycoprotein (PGP). PGP inhibited the production of NO and ROS and expression of iNOS, COX-2, TNF-α and IL-1β, which are involved in the pathogenesis of many inflammation-associated human diseases, including septic shock, hemorrhagic shock and rheumatoid arthritis. Next, we determined the mechanisms behind the antioxidant and anti-inflammatory activities of PGP. We focused on the Toll-like receptor 4 (TLR4) signaling pathway because it is well-known to induce the pro-inflammatory proteins that trigger MAPK and NF-κB activation in lipopolysaccharide (LPS)-induced oxidative events. PGP treatment reduced the formation of the TLR4-IRAK4 and TLR4-TRIF binding complexes in response to LPS. Moreover, it inhibited LPS-induced activation and nuclear translocation of NF-κB by abrogating IκB phosphorylation. PGP also suppressed the phosphorylation of ERK1/2 and JNK in a dose-dependent manner. These results suggest that PGP exerts its anti-inflammatory effects by modulating TLR4 signaling and thus inhibiting the activation of NF-κB and MAP kinases.

Hint for association of single nucleotide polymorphisms and haplotype in SPINK5 gene with atopic dermatitis in Koreans

Clinical studies, including twin studies, support the concept that the risk of atopic dermatitis (AD) may be mediated through skin-specific genes, rather than simply through systemic immune or atopy risk genes. The SPINK5 gene is expressed on epithelial surfaces and may provide protection against other allergenic serine proteases. Mutations in the SPINK5 gene result in Netherton syndrome, a disorder characterised by AD, ichthyosis, and elevated serum IgE levels. We genotyped 21 single nucleotide polymorphisms (SNPs) from the SPINK5 gene for 1090 case-control samples (631 patients with AD and 459 normal controls) and analysed the SNPs and haplotypes in this gene and also searched for gene-gene interactions between SPINK5 and the DEFB1 gene that we previously reported. Six SNPs [rs17718511 (P = 0.026), rs17860502 (P = 0.024), KN0001820 (P = 0.045), rs60978485 (P = 0.007), rs17718737 (P = 0.02), and rs1422985 (P = 0.038)] and the haplotype TAA (rs60978485, rs6892205, rs2303064; P = 0.023) in the SPINK5 gene showed significant different allelic or genotypic distributions between the AD group and the control group. We also found that four SNPs [rs17718511 (P = 0.033), rs17860502 (P = 0.031), rs60978485 (P = 0.005), rs17718737 (P = 0.023)] and the haplotype TAA (P = 0.02) in the SPINK5 gene showed associations with the susceptibility of the allergic type of AD (ADe). In addition to this finding, we speculate that the SNPs from DEFB1 and SPINK5 affect the individual susceptibility to development of ADe in an additive manner. This study provides evidence for a significant interaction between allergens and the SPINK5 gene that may contribute to ADe susceptibility.

An association between IL-9 and IL-9 receptor gene polymorphisms and atopic dermatitis in a Korean population

BACKGROUND

The genes encoding IL-9 and IL-9R have recently been implicated in the genetic basis of asthma and allergy. Although studies performed on transgenic and knockout mice have shown conflicting results, no evidence of skin changes has ever been reported in these animals.

OBJECTIVE

To find association of the SNPs in IL-9 and IL-9R genes and interaction of these genes in atopic dermatitis.

METHOD

We genotyped 5 SNPs from the IL-9 and IL-9R genes of 1090 subject samples (631 AD patients and 459 normal controls). A luciferase assay was then performed for the rs31563 (-4091G/A) SNP located in the IL-9 gene promoter region.

RESULT

The rs31563 (-4091G/A) SNP in the IL-9 gene was significantly associated with the AD phenotype, especially allergic-type AD. In the luciferase assay, the rs31563 G construct was observed to have 1.54 times higher activity than the rs31563 A construct. Although no association was found between SNPs in IL-9R gene and AD, the rs3093467 SNP showed association with non-allergic AD. In the gene-gene interaction analysis, we found that IL-9/IL-9R genotype rs31563 GG/rs3093467 TT conveyed a greater risk for AD phenotype development.

CONCLUSION

Significant evidence exists to suggest that the rs31563 SNP (-4091G/A) located in the IL-9 gene is associated with an increased susceptibility to AD. Similarly, the rs3093467 SNP in IL-9R gene seems to be associated with an increased risk for developing non-allergic AD. In a subsequent gene-gene interaction analysis, the rs31563 GG/rs3093467 TT genotype combination (IL-9/IL-9R) was found to exert a synergistic effect in the development of the AD phenotype. As the classes of helper T cells are diverse and the function of IL-9 cytokine has not been fully described, the cutaneous function of IL-9 needs to be further explored in future studies.

Adiponectin concentrations: a genome-wide association study

Adiponectin is associated with obesity and insulin resistance. To date, there has been no genome-wide association study (GWAS) of adiponectin levels in Asians. Here we present a GWAS of a cohort of Korean volunteers. A total of 4,001 subjects were genotyped by using a genome-wide marker panel in a two-stage design (979 subjects initially and 3,022 in a second stage). Another 2,304 subjects were used for follow-up replication studies with selected markers. In the discovery phase, the top SNP associated with mean log adiponectin was rs3865188 in CDH13 on chromosome 16 (p = 1.69 × 10(-15) in the initial sample, p = 6.58 × 10(-39) in the second genome-wide sample, and p = 2.12 × 10(-32) in the replication sample). The meta-analysis p value for rs3865188 in all 6,305 individuals was 2.82 × 10(-83). The association of rs3865188 with high-molecular-weight adiponectin (p = 7.36 × 10(-58)) was even stronger in the third sample. A reporter assay that evaluated the effects of a CDH13 promoter SNP in complete linkage disequilibrium with rs3865188 revealed that the major allele increased expression 2.2-fold. This study clearly shows that genetic variants in CDH13 influence adiponectin levels in Korean adults.

Association between genetic variations of the transforming growth factor ß receptor type III and asthma in a Korean population

Transforming growth factor-beta (TGF-ß) and its receptors have been suggested to play key roles in the pathogenesis of asthma. The aim of this study was to evaluate the effects of genetic variations in the TGF-ß receptor type III (TGFBR3) on asthma and on its related phenotypes in the general population. A cohort of 2,118 subjects aged from 10 to 18 years responded to a questionnaire concerning asthma symptoms and risk factors. Methacholine airway hyperresponsiveness (AHR), skin test responses to common aeroallergens, and serum total IgE levels were evaluated in the cohort. A total of 19 SNPs for TGFBR3 were found using direct re-sequencing in 24 healthy adults. Of these, informative SNPs [+44T>C (S15F) and +2753G>A at 3'UTR] were selected and scored using the high throughput single base extension method. Atopy was identified in subjects with 44T>C allele [P=0.04, OR (95% CI)=0.79 (0.62-0.99)] and in subjects with Ht1 (CG) more frequently than in subjects with other haplotypes [P=0.04, OR (95% CI)=1.27 (1.01-1.59)]. The A allele in 2753G>A was more common in subjects with non-atopic asthma [OR (95% CI)=1.76 (1.01-3.05)]. A significant association was found between non-atopic asthma and 44T_2753A [OR (95% CI) =2.16 (1.22-3.82)]. Genetic variations in TGFBR3 appear to be associated with a genetic predisposition to development of asthma and to phenotypes of asthma. Also, the minor allele 2753G and the haplotype TA in the TGFBR3 gene were associated with a pathogenesis of non-atopic asthma.

Association of signal transducer and activator of transcription 4 genetic variants with extra-intestinal manifestations in inflammatory bowel disease

AIMS

The STAT4 gene encodes a transcription factor which plays an important role in the development of inflammation of many immune-mediated diseases. We investigated the relationship between STAT4 single nucleotide polymorphisms (SNPs) and susceptibility to ulcerative colitis (UC) and Crohn's disease (CD) and disease phenotypes in the Korean population.

MAIN METHODS

We performed a case-control association study in individuals with UC (N=246), CD (N=182), and healthy controls (N=229).

KEY FINDINGS

We genotyped 8 STAT4 SNPs (rs11889341, rs7574865, rs8179673, rs6752770, rs925847, rs10168266, rs10181656, and rs11685878) in the STAT4 gene in patients and controls. SNP rs925847 in the STAT4 gene was significantly associated with susceptibility to UC (P=0.025; OR=0.63) in dominant genotype analysis, though none of these SNPs were associated with CD susceptibility. Moreover, a significant association was identified between SNP rs11889341 and joint involvement (P=0.040; OR=3.79), and between SNP rs925847 and eye involvement (P=0.030; OR=2.42) in UC patients. For CD, rs925847 genetic variant was associated with joint (P=0.029; OR=3.93) and perianal lesions (P=0.033; OR=2.27).

SIGNIFICANCE

Our data demonstrated that the STAT4 genetic variants could predispose an individual to IBD and its extra-intestinal ailments in Koreans, suggesting the common pathogenesis of IBD (especially, extra-intestinal manifestations) and other autoimmune diseases.

Genetic polymorphisms of drug-metabolizing enzymes and anti-TB drug-induced hepatitis

AIMS

Although some genetic risk factors have been reported for the development of hepatitis due to anti-TB drugs, an extensive candidate gene approach evaluating drug-metabolizing enzymes has not been attempted. This study aimed to investigate the association of genetic polymorphisms in drug-metabolizing enzymes with anti-TB drug-induced hepatitis.

MATERIALS & METHODS

We compared genotype distributions of tagging SNPs in promoter, exons and haplotypes in seven drug-metabolizing enzyme genes (CYP2C9, CYP2C19, CYP2D6, CYP2E1, NAT2, UGT1A1 and UGT1A3) between 67 cases and 159 controls.

RESULTS

Among four tagging SNPs of N-acetyltransferase 2 (NAT2), -9796T>A in promoter and R197Q were significantly associated (p = 0.0016 and p = 0.0007, respectively). NAT2 haplotype 2 [A-A-A-G] carrying A allele of -9796T>A and A allele of R197Q showed significant association (p = 0.0004). However, there was no significant association between genotypes of other enzyme-metabolizing genes and anti-TB drug-induced hepatitis. The constructs containing -9796A of NAT2 showed significantly lower luciferase activity (p < 0.01), suggesting decreased expression of NAT2. The variant alleles and haplotype 2 showed significantly higher peak serum levels of isoniazid, lower acetyl isoniazid:isoniazid ratio and lower isoniazid clearance compared with wild-types.

CONCLUSION

These findings suggest that genetic variants in the promoter and exons of NAT2 increase the risk of anti-TB drug-induced hepatitis by modifying acetylation phenotypes and/or gene expression of NAT2, and there is no essential role for genetic mutation of the other metabolizing enzymes in the development of this adverse reaction.

The LRRK2 G2385R variant is a risk factor for sporadic Parkinson's disease in the Korean population

The G2385R (SNP accession no. rs34778348) and R1628P (rs33949390) variants of leucine-rich repeat kinase 2 (LRRK2, PARK8) are emerging as an important risk factor for Parkinson's disease (PD) in the ethnic Chinese and Japanese populations. The purpose of this study was to investigate whether these variants are a genetic risk factor in sporadic PD patients in the Korean population. A total of 923 patients and 422 healthy subjects were included. The variants were screened by a SNaPshot assay. The LRRK2 G2385R variant was detected in 82 PD patients (8.9%, two homozygous and 80 heterozygous) and in 21 normal controls (5.0%, all heterozygous). The frequency of the LRRK2 G2385R variant in PD was significantly higher than in normal controls (adjusted odds ratio 1.83, p = 0.0170, 95% confidence interval 1.11-3.00). There were no differences in the mean age at onset or gender between the G2385R carriers and the non-carriers in PD patients. The LRRK2 R1628P variant was very rare (0.78% in patients versus 0.26% in controls) in the tested 384 patient-control pairs, and was not a significant risk factor. This study supports that the LRRK2 G2385R variant may be a genetic risk factor for sporadic PD in the Korean population.

Polymorphisms in the Annexin gene family and the risk of osteonecrosis of the femoral head in the Korean population

OBJECTIVE

The pathogenesis of osteonecrosis of the femoral head (ONFH) probably reflects multiple etiologies. Recent studies have explored associations between genetic mutations and/or polymorphisms and ONFH. Annexins (ANXs) have been implicated in many physiological functions, including blood coagulation, inflammation, apoptosis, as well as Ca(2+) homeostasis in bone cells, all of which may be associated with ONFH. The aim of this study was to evaluate the possible association of AnnexinA (ANXA) family gene polymorphisms with ONFH.

METHODS

52 SNPs from three genes of the ANXA family were selected from public databases and genotyped in 443 ONFH patients and 273 control subjects using the Affymetrix Targeted Genotyping 3 K Chip array. The association analysis of genotyped SNPs and haplotypes was performed with ONFH.

RESULTS

Among the polymorphisms tested of the ANXA family gene, the rs9324679, rs9324677, rs10037814, and rs11960458 SNPs of the ANXA6 gene were significantly associated with the risk of ONFH in all alternative analysis models (p range; 0.0007-0.049, odds ratio (OR); 0.63-1.72). Further analysis stratified by pathological etiology showed that these SNPs were also associated with the risk of ONFH in at least one subgroup (p range; 0.0017-0.049). Haplotype association analysis showed that several haplotypes were significantly associated with a risk of ONFH, with p values ranging between 0.0005 and 0.049 (OR range; 0.44-1.76).

CONCLUSIONS

These findings indicate that the polymorphisms of ANXA6 are associated with ONFH. Thus, these polymorphisms may be useful genetic markers to identify high-risk individuals.

Single-nucleotide polymorphisms in the promoter of the CDK5 gene and lung cancer risk in a Korean population

Cyclin-dependent kinase 5 (CDK5), a proline-directed serine/threonine kinase, which was originally known for its regulatory role in neuronal activities, has recently been suggested to play a role in extraneuronal activities. For example, a recent study detected overexpression of the CDK5 gene in non-small-cell lung cancer. Therefore, in order to explore the association of the CDK5 gene with lung cancer risk in a Korean population, the genotypes of the CDK5 promoter region were determined in 407 lung cancer patients and 402 normal participants. The result showed that the -904 G>A genotype affected susceptibility to lung cancer risk (odd ratios (OR)=1.53, 95% confidence interval (CI)=1.02-2.32). Furthermore, subsequent haplotype analysis of three single-nucleotide polymorphism (SNP) regions suggested that the A-G-C haplotype was associated with a higher overall risk of lung cancer (OR=1.59, 95% CI=1.16-2.18). These results suggest that CDK5 promoter polymorphisms contribute to the genetic susceptibility to lung cancer in the Korean population.

Effect of BRCA1 Haplotype on Survival of Non–Small-Cell Lung Cancer Patients Treated With Platinum-Based Chemotherapy

Purpose

To determine whether germ-line variations in BRCA1 affect outcome in non–small-cell lung cancer (NSCLC) patients treated with platinum combination chemotherapy.

Patients and Methods

We evaluated the associations of four tagging BRCA1 polymorphisms and their haplotypes with treatment outcome in 300 NSCLC patients at stages IIIA (16%), IIIB (31%), and IV (53%).

Results

The median age was 63 years (range, 28 to 89 years). Histologically, 139 (46.3%) of the patients had squamous cell carcinomas and 137 (45.7%) had adenocarcinomas. Patient median survival time (MST) was 13.0 months. We observed no significant association between any of the tagging polymorphisms [S1613G, IVS13-1893 (A>C), IVS12-1207 (C>T), and IVS12+112 (C>A)] and overall survival. Of the five haplotypes evaluated (AACC, AACA, GCTC, GATC, and AATC), the survival of patients with two copies of the AACC (wild-type) haplotype was significantly shorter than that of patients with zero to one copies (MST, 8.47 v 14.57 months; log-rank P = .0066), even after adjustment for body weight loss, performance status, stage, second-line treatment, and radiation therapy (hazard ratio = 2.097; 95% CI, 1.339 to 3.284). The survival of patients with squamous cell carcinoma and two copies was significantly shorter than that of other patients with squamous cell carcinoma (MST, 6.8 v 15.3 months; log-rank P = 3.6 × 10−5), whereas differences in survival between the two adenocarcinoma groups was not significant (log-rank P = .677).

Conclusion

These findings suggest that the AACC haplotype of the BRCA1 gene is an important prognostic marker in NSCLC patients treated with platinum combination chemotherapy.

Single nucleotide polymorphism of COL6A1 in patients with ankylosing spondylitis

OBJECTIVE

To investigate the genetic association between ankylosing spondylitis (AS) and single nucleotide polymorphisms (SNP) of collagen 6A1 gene (COL6A1), the candidate gene for ossification of the posterior longitudinal ligament.

METHODS

One-hundred thirty Korean patients with AS (M: 116, F: 14, age: 29.0 +/- 4.6) and 130 age- and sex-matched healthy subjects were recruited. The SNP of G365G, IVS15+39 C/T, IVS21+18 A/C by Snap shot assay and the SNP of IVS32-29T/C, IVS33+15G/A, IVS33+20A/G, and IVS33+55A/G by direct sequencing were genotyped and analyzed. Bonferroni correction was applied to multiple comparisons.

RESULTS

The observed allelic frequencies for these SNP met Hardy-Weinberg equilibrium in all AS and controls. We also found an additional 2 SNP (R783Q and IVS33+88C/T) during direct sequencing. Therefore, a total of 9 SNP were analyzed in this study. There were no significant associations of allelic and genotype variations between AS and controls. The presence of uveitis was marginally associated with a haplotype (CC in G365G + IVS15+39 C/T). The variation of allele or haplotype of COL6A1 is not significantly associated with "more ossified disease."

CONCLUSION

Because the genetic variations of COL6A1 could not be correlated with the occurrence of AS in Koreans, we conclude that despite common clinical features, AS and ossification of posterior longitudinal ligament are not genetically related, and the hyperostotic condition seen in the 2 diseases might be regulated differently. Further SNP of COL6A1 were not related to radiographic progression of AS. However, we found that the occurrence of uveitis might be related to the genetic variations of COL6A1 in patients with AS.

Association between polymorphisms in prostanoid receptor genes and aspirin-intolerant asthma

BACKGROUND

Genetic predisposition is linked to the pathogenesis of aspirin-intolerant asthma. Most candidate gene approaches have focused on leukotriene-related pathways, whereas there have been relatively few studies evaluating the effects of polymorphisms in prostanoid receptor genes on the development of aspirin-intolerant asthma. Therefore, we investigated the potential association between prostanoid receptor gene polymorphisms and the aspirin-intolerant asthma phenotype.

METHODS

We screened for genetic variations in the prostanoid receptor genes PTGER1, PTGER2, PTGER3, PTGER4, PTGDR, PTGIR, PTGFR, and TBXA2R using direct sequencing, and selected 32 tagging single nucleotide polymorphisms among the 77 polymorphisms with frequencies >0.02 based on linkage disequilibrium for genotyping. We compared the genotype distributions and allele frequencies of three participant groups (108 patients with aspirin-intolerant asthma, 93 patients with aspirin-tolerant asthma, and 140 normal controls).

RESULTS

Through association analyses studies of the 32 single nucleotide polymorphisms, the following single nucleotide polymorphisms were found to have significant associations with the aspirin-intolerant asthma phenotype: -616C>G (P=0.038) and -166G>A (P=0.023) in PTGER2; -1709T>A (P=0.043) in PTGER3; -1254A>G (P=0.018) in PTGER4; 1915T>C (P=0.015) in PTGIR; and -4684C>T (P=0.027), and 795T>C (P=0.032) in TBXA2R. In the haplotype analysis of each gene, the frequency of PTGIR ht3[G-G-C-C], which includes 1915T>C, differed significantly between the aspirin-intolerant asthma patients and aspirin-tolerant asthma patients (P=0.015).

CONCLUSION

These findings suggest that genetic polymorphisms in PTGER2, PTGER3, PTGER4, PTGIR, and TBXA2R play important roles in the pathogenesis of aspirin-intolerant asthma.

Human leukocyte antigen alleles and haplotypes associated with chronicity of hepatitis B virus infection in Koreans

CONTEXT

Chronic hepatitis B infection is the leading cause of cirrhosis and hepatocellular carcinoma. Human leukocyte antigen may be involved in the chronicity of hepatitis B virus (HBV) infection.

OBJECTIVE

To analyze the association between HBV chronicity and human leukocyte antigen alleles and haplotypes of 636 organ donors and recipients.

DESIGN

Subjects were categorized into 2 groups according to their clinical and serologic profiles, specifically, an HBV natural convalescent group and an HBV chronic carrier (CC) group.

RESULTS

Hepatitis B chronicity was positively associated with A33 (P = .004, odds ratio [OR] = 1.59) and DR7 (P < .001, OR = 2.58), and negatively associated with HLA-DR13 (P < .001, OR = 0.40). Coexpression of A33 and DR7 was significantly higher in the CC group (OR = 3.63), compared with that of either allele alone (OR = 1.76 in A33; OR = 2.53 in DR7). The statistically significant haplotypes were B44-DR7 (P < .001, OR = 5.44), A33-DR7 (P < .001, OR = 4.47), and A33-B44-DR7 (P < .001, OR = 7.31) in the CC group.

CONCLUSIONS

Our results indicate that alleles of A33, DR7, and haplotypes containing DR7 are associated with HBV chronicity among Koreans. Moreover, the 2 antigens had an additive effect on chronicity. These findings support the theory that human leukocyte antigen class I-restricted cytotoxic T cells and human leukocyte antigen class II-restricted helper T cells play an important role in HBV chronicity.

Multilocus analysis of atopy in Korean children using multifactor-dimensionality reduction

BACKGROUND

Atopy is considered to be a complex genetic trait and does not follow a simple mendelian pattern of inheritance. It is now well recognised that gene-gene interactions are important in complex genetic disease.

AIM

To analyse the influence of gene-gene interactions in the development of atopy.

METHODS

A total of 2055 ethnically identical participants aged 10-18 years living in rural areas on Jeju Island, Korea, were randomly recruited. Atopy was defined as a positive skin prick test response to one or more common inhalant allergens. Gene-gene interactions among 12 polymorphic loci were analysed in the seven candidate genes of atopy using the multidimensionality-reduction method.

RESULTS

A significant interaction was found between V297I in the gene coding vascular endothelial growth factor receptor 2 (KDR) and -308G-->A in the gene coding tumour necrosis factor (TNF)alpha on the risk of atopy, with a cross-validation consistency of 10 out of 10 and a prediction error of 35.9% (p = 0.001). Conventional logistic regression also revealed significant interactions between KDR and TNF for atopy. Individuals with the variant allele of -308G-->A in TNF (GA or AA) and V297I in KDR (VI or II) had a significantly higher risk of atopy (OR 2.23; 95% CI 1.48 to 3.57).

CONCLUSION

KDR and TNF may synergistically influence the development of atopy through gene-gene interaction in Korean children and adolescents.

Gene-gene interaction between IL-13 and IL-13Ralpha1 is associated with total IgE in Korean children with atopic asthma

Interleukin (IL)-13, which is essential for IgE synthesis, mediates its effects by binding with a receptor composed of IL-4Ralpha and IL-13Ralpha1. We investigated the effects of IL-13 and IL-13Ralpha1 polymorphisms in Korean children with asthma, and whether these have been associated with IgE production. We enrolled 358 atopic asthmatic, 111 non-atopic asthmatic, and 146 non-atopic healthy children. IL-13 and IL-13Ralpha1 genotypes were identified using the PCR-RFLP method. There was an association between the asthma susceptibility and homozygosity for risk allele of IL-13 G+2044A. In children with atopic asthma, risk alleles in IL-13 (A-1512C and C-1112T) and IL-13Ralpha1 (A+1398G) showed increased total IgE (P=0.012, 0.015 and 0.017, respectively). Three-loci haplotype analysis for IL-13 showed that the haplotype composed of -1512C, -1112T and +2044A was associated with higher total IgE than other tested haplotypes in children with atopic asthma (P=0.003). The gene-gene interaction between risk alleles of each IL-13 promoter polymorphism and IL-13Ralpha1 polymorphism was associated with higher total IgE in children with atopic asthma (P=0.002, 0.010). These findings indicate that the IL-13 G+2044A is associated with asthma development and the IL-13 and IL-13Ralpha1 polymorphisms may interact to enhance IgE production.

Association between genetic variations of vascular endothelial growth factor receptor 2 and atopy in the Korean population

BACKGROUND

Vascular endothelial growth factor (VEGF) has been suggested to be a key mediator in the development of atopy and T(H)2 inflammation.

OBJECTIVE

We sought to evaluate the effects of variations in the gene coding VEGF receptor (VEGFR) 2 on intermediate phenotypes of asthma in the Korean population.

METHODS

A cohort of 2055 children and adolescents responded to a questionnaire concerning asthma symptoms and risk factors and underwent methacholine bronchial challenge and skin tests. The VEGFR2 gene, including the promoter area, was sequenced on 24 healthy subjects to discover informative single nucleotide polymorphisms (SNPs; minor allele frequency >2%). After haplotype reconstruction, 4 tagging SNPs (IVS6+54A>G, +889G>A, +1416T>A, and IVS25-92G>A) were scored. These SNPs were also scored in 480 adult asthmatic patients to verify the above genetic association study.

RESULTS

The prevalence of atopy was associated with a single SNP (+889G>A) of VEGFR2 with borderline significance (P = .048; relative risk, 1.13; 95% CI, 1.00-1.28). However, haplotype analysis showed that the atopy prevalence was strongly associated with a haplotype (AGAG) of VEGFR2 (P = .002; relative risk, 1.25; 95% CI, 1.09-1.42). As for airway hyperresponsiveness, neither individual SNPs nor haplotypes were found to be associated. Interestingly, the significant association was also found between atopy and the AGAG haplotype among adult asthmatic patients (P = .008; odds ratio, 1.66; 95% CI, 1.14-2.44).

CONCLUSIONS

The present study demonstrated that genetic variations of VEGFR2 are significantly associated with atopy in the Korean population.

Positive regulation of hepatic carnitine palmitoyl transferase 1A (CPT1A) activities by soy isoflavones and L-carnitine

BACKGROUND

Genistein increases CPT1A, a rate-limiting enzyme in the beta-oxidation pathway, enzyme activity by increasing CPT1A transcription in HepG2 cells and, consequently, suppresses high fat induced obesity in C57BL/6J mice. Genistein and daidzein are the most abundant isoflavones in soy.

AIM OF STUDY

To investigate the effect of co-treatment of genistein and L-carnitine on CPT1A enzyme activity and to determine whether daidzein also increases CPT1A activity and to establish a cell line that can be used to screen chemicals to regulate CPT1A transcription.

METHODS

The enzyme activities of CPT1A were determined after HepG2 cells were incubated with 10 microM genistein or 10 microM daidzein or 1 mM L-carnitine or in combination with 10 microM genistein and 1 mM L-carnitine or in combination with 10 microM daidzein and 1 mM L-carnitine. The mRNA expression levels of CPT1A were determined by real time PCR method after HepG2 cells were incubated with 10 microM genistein or 10 microM daidzein. A suggested CPT1A promoter region was cloned from human genomic DNA and the CPT1A promoter-luciferase reporter gene construct was made, and the promoter-reporter gene construct was transfected into human hepatoma cell line Huh7.

RESULTS

The enzyme activity of CPT1A was at least 2.3- fold higher in L-carnitine and genistein co-treated HepG2 cells than either single-agent treated cells. Daidzein also significantly increased the mRNA expression of CPT1A as well as the enzyme activity of CPT1A. A stable Huh7 cell line, which was selected after Huh7 cells were transfected with CPT1A promoter luciferase reporter gene construct, was characterized by confirming that luciferase activity of the cell line can be regulated by genistein and daidzein as well as clofibrate, a well-known CPT1A mRNA up-regulating drug.

CONCLUSIONS

Genistein and daidzein can up-regulate CPT1A enzyme activity through up-regulation of CPT1A transcription. Co-treatment of L-carnitine and genistein additively increases CPT1A enzyme activity in HepG2 cells. A stable Huh7 cell line transfected with the CPT1A promoter luciferase reporter gene was established and characterized.

A Haplotype Analysis of HER-2 Gene Polymorphisms: Association with Breast Cancer Risk, HER-2 Protein Expression in the Tumor, and Disease Recurrence in Korea

PURPOSE

A single-nucleotide polymorphism (SNP) in codon 655 of HER-2 has been extensively studied with inconclusive results. The purpose of this study was to investigate the association between common variants of HER-2 and breast cancer risk, HER-2 expression, and survival using a haplotype-based stepwise approach.

EXPERIMENTAL DESIGN

Twenty-nine SNPs listed in the National Center for Biotechnology Information database were screened to identify novel polymorphisms of HER-2 gene in 90 healthy Korean women. Six of 29 SNPs were polymorphic and had greater than 10% of minor allele frequencies. Using these six SNPs, linkage disequilibrium and haplotype patterns were characterized. We tested association between the haplotypes and breast cancer in a large case-control study (n=1,039 cases and 995 controls). Six-hundred two breast cancer patients with follow-up at least 24 months were analyzed for outcome in relation to haplotype. Expression of HER-2 protein was determined by immunohistochemistry in 1,094 cases of invasive breast cancer.

RESULTS

All six SNPs showed a strong linkage disequilibrium pattern and were considered to belong to one haplotype block. Two haplotype-tagging SNPs (I655V and P1170A) for three common haplotypes (>5%) were genotyped in cases and controls. The haplotypes and individual SNPs were not associated with breast cancer risk. In patients with at least one copy of haplotype I (the most common haplotype), HER-2 expression was 1.5 times higher (P = 0.009) and the prognosis was worse (P = 0.032) compared with patients without having that haplotype.

CONCLUSIONS

Our results suggest that the currently identified genetic polymorphisms of HER-2 are not associated with an increased risk of breast cancer in Korean women, whereas one haplotype does affect protein expression of the tumor and disease outcome.

IL-5 and thromboxane A2 receptor gene polymorphisms are associated with decreased pulmonary function in Korean children with atopic asthma

BACKGROUND

Asthmatic airways undergo chronic inflammatory cell infiltration by T cells and eosinophils, which results in sustained airway hyperresponsiveness. IL-5 is important for eosinophil-induced airway inflammation and airway hyperresponsiveness. Thromboxane A2 and its receptor, TBXA2R, are involved in constriction of respiratory smooth muscles and may play a role in thickening and remodeling of airways, which contributes to the severity of asthma. The relationship between IL-5 and TBXA2R gene polymorphisms and pulmonary function in children with asthma has rarely been examined.

OBJECTIVE

To determine whether IL-5 (T-746C) and TBXA2R (T924C) gene polymorphisms are associated with asthma phenotype and pulmonary function in Korean children with atopic and nonatopic asthma.

METHODS

We conducted an association study between known polymorphisms of IL-5 (T-746C) and TBXA2R (T924C) and asthma phenotype and the parameters of atopy and pulmonary function in atopic and nonatopic Korean children with asthma. The subjects were 240 atopic children with asthma, 70 nonatopic children with asthma, and 106 nonatopic healthy children. Asthma phenotypes and bronchial responsiveness to methacholine were determined by a physician. IL-5 and TBXA2R gene polymorphisms were determined by genotyping by using PCR-RFLP assays.

RESULTS

The genotype frequencies of IL-5 and TBXA2R polymorphisms did not differ between healthy controls and atopic or nonatopic children with asthma. A significant association was observed between the IL-5 polymorphism and forced expiratory flow at 25% to 75% of forced vital capacity (FEF 25-75% ; %; P = .002), and between the TBXA2R polymorphism and FEV 1 (%; P = .035) and FEF 25-75% (%; P = .042) in children with atopic asthma, whereas no such association between the polymorphisms and lung function was observed in nonatopic or control children. In atopic children with asthma, we identified a significant gene-gene interaction in that the combination of the IL-5 (T-746C) and TBXA2R (T924C) mutant alleles was shown to be associated with reduced pulmonary function as determined by FEF 25-75% (%) measurement.

CONCLUSION

The current study indicates that IL-5 (T-746C) and TBXA2R (T924C) polymorphisms alone are associated with spirometric markers of asthma severity, whereas they are not associated with presence of asthma per se. In addition, the data suggest that an interaction between IL-5 and TBXA2R genes may contribute to the severity of asthma, especially atopic asthma. These results suggest that IL-5 and TBXA2R genes may be disease-modifying genes in Korean children with atopic asthma.

Transjugular intrahepatic portosystemic shunt placement in the setting of polycystic liver disease: questioning the contraindication

Although polycystic liver disease has long been listed as a contraindication to transjugular intrahepatic portosystemic shunt (TIPS) creation, two cases of TIPS placement in that particular clinical setting have been reported. Another case is reported in this article and the clinical course over 21 months of follow-up is examined. The discussion reviews the mechanics of TIPS creation in a polycystic liver and the vague premise of the polycystic liver as a contraindication to TIPS.

Effect of weight control on hepatic abnormalities in obese patients with fatty liver

This study was aimed at finding out whether weight reduction alone can improve liver function in obese patients with fatty liver. We did a longitudinal, clinical intervention study on weight reduction by behavior modification, diet and exercise. The study subjects were 25 patients referred to an obesity clinic in whom obesity is the sole factor causing abnormal liver function and fatty liver. Patients were weighed about one year later. We compared the degree of improvement in hepatic function between Group I that showed weight reduction and Group II that showed no-weight reduction. Group I (13) showed dramatic improvement in aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, nearly all down to within normal levels. AST showed statistically significant improvement from 74 +/- 36 IU/l to 25 +/- 7 IU/l. ALT also showed statistically significant improvement from 109 +/- 67 IU/l to 30 +/- 14 IU/l. Group II (12) showed higher AST and ALT levels on follow-up visit than initial visit. AST showed statistically significant elevation from 43 +/- 11 IU/l to 59 +/- 23 IU/l. ALT also showed statistically significant elevation from 64 +/- 21 IU/l to 97 +/- 33 IU/l. If we can rule the other causes of hepatic abnormalities in obese patients with fatty liver, we suggest these patients would benefit by weight reduction.