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The common data model (CDM) has found widespread application in healthcare studies, but its utilization in cancer research has been limited. This article describes the development and implementation strategy for Cancer Clinical Library Databases (CCLDs), which are standardized cancer-specific databases established under the Korea-Clinical Data Utilization Network for Research Excellence (K-CURE) project by the Korean Ministry of Health and Welfare. Fifteen leading hospitals and fourteen academic associations in Korea are engaged in constructing CCLDs for 10 primary cancer types. For each cancer type-specific CCLD, cancer data experts determine key clinical data items essential for cancer research, standardize these items across cancer types, and create a standardized schema. Comprehensive clinical records covering diagnosis, treatment, and outcomes, with annual updates, are collected for each cancer patient in the target population, and quality control is based on six-sigma standards. To protect patient privacy, CCLDs follow stringent data security guidelines by pseudonymizing personal identification information and operating within a closed analysis environment. Researchers can apply for access to CCLD data through the K-CURE portal, which is subject to Institutional Review Board and Data Review Board approval. The CCLD is considered a pioneering standardized cancer-specific database, significantly representing Korea's cancer data. It is expected to overcome limitations of previous CDMs and provide a valuable resource for multicenter cancer research in Korea.

Objective: To investigate the association between the aryl hydrocarbon receptor repressor (AhRR) C/G polymorphisms and glutathione-S-transferase M1 (GSTM1) and GSTT1 null mutation and the risk of polycystic ovary syndrome (PCOS) in Korean women., Methods: This was a case-control study of 478 women with PCOS and 376 aged-matched healthy controls. Genotyping of the AhRR C/G polymorphism and GSTM1 and GSTT1 were performed using real-time PCR analysis and multiplex PCR, respectively., Results: The genotype distribution of the AhRR C/G polymorphisms and GSTM1/GSTT1 null mutations did not differ between women with PCOS and controls. Using the wild-type combined AhRR CC and GSTT1 present genotype as a reference, the odds that a woman had PCOS were 1.54 (95% CIs 1.04-2.29) times higher if she had a combined AhRR CG or GG and GSTT1 null genotype. The odds that a woman had PCOS was 1.48 (95% CIs 1.08-2.04) times higher if she had a combined GSTM1/GSTT1 null genotype compared with the wild-type combined GSTM1/GSTT1 present genotype. However, there were no significant associations between the risk of PCOS and any combined AhRR and GSTM1., Conclusions: Our data suggest that a combined AhRR CG or GG and GSTT1 null genotype or a combined GSTT1/GSTM1 null genotype might be associated with an increased risk of PCOS.

Aberrant apoptosis at the trophoblast-maternal interface and abnormal expression of Fas and Fas ligand (FasL) have been reported in complicated pregnancies with recurrent pregnancy losses (RPL) and preeclampsia. We assessed the prevalence of Fas and FasL genetic polymorphisms in Korean women with RPL and in fertile controls. In total, 306 women with RPL and 298 fertile controls were enrolled. Genotype distributions of Fas and FasL in RPL patients versus fertile controls were examined under the Hardy-Weinberg equilibrium. Fas -670 A/G genotype (AA versus AG versus GG, p  = 0.340) and allele frequencies (A versus G, p  = 0.412) were not different between the RPL and control groups. There was no difference in each Fas -1377 G/A and FasL -844 C/T genotype, and their allele frequencies. In addition, the unions of two zygosities of each genotype and their combined genotypes did not differ between two groups. No difference in the prevalence of Fas and FasL single-nucleotide polymorphisms (SNPs) was observed between women with RPL and fertile controls among Korean women. To determine the possibility of genetic polymorphisms in Fas and its ligand as risk factors for RPL, further studies in various races and a large study population are needed.

The balance between coagulation and fibrinolysis is an essential part in early pregnancy. Mutations in methylenetetrahydrofolate reductase (MTHFR) gene lead to decreased activity of the enzyme and hyperhomocysteinemia, which then induces platelet aggregation by promoting endothelial oxidative damage, possibly resulting in adverse effect on maintenance of pregnancy. We investigated the role of MTHFR single nucleotide polymorphisms (SNPs), C677T and A1298C, in Korean patients with recurrent pregnancy loss (RPL). We conducted a prospective case-control study in the Korean population. Subjects included 302 women with 2 or more consecutive, unexplained, spontaneous miscarriages before 20 weeks of gestation and 315 control women without a history of recurrent miscarriages. The genotyping for C677T and A1298C polymorphisms was performed using the TaqMan assay. Continuous variables were compared using Student's t-test, and χ² test was used to evaluate differences in the genotype distributions between the RPL and the controls. The genotype distribution of both polymorphisms in the RPL group did not differ from those of the controls. For further analysis, if RPL patients were divided according to the numbers of pregnancy losses (≥ 2 and ≥ 3) neither group was significantly different compared with controls. MTHFR gene C677T and A1298C polymorphisms are not associated with idiopathic RPL in Korean women, suggesting that those may not be susceptible allelic variants or be deficient to cause RPL., Competing Interests: The authors have no potential conflicts of interest to disclose., (© 2017 The Korean Academy of Medical Sciences.)

Objective: The balance of apoptosis and proliferation is an important part in the embryonic development during pregnancy. It has been reported that the p53 gene plays a significant role in angiogenesis and placental development, namely in reproduction and is suggested as a potential mediator of pregnancy. This study was performed to investigate whether the genetic polymorphism of the p53 gene is associated with idiopathic recurrent pregnancy loss (RPL)., Study Design: We conducted a case-control study in the Korean population. Study subjects consisted of 294 patients with idiopathic RPL and 300 postmenopausal controls. The genotyping for the p53 codon 72 polymorphism was performed using a Taqman assay. Continuous variables were compared using Student's t test and the χ(2) test was used to evaluate differences in the genotype distributions between the RPL and the controls., Results: There were no significant differences in the genotype distributions or allele frequencies of the p53 codon 72 polymorphism between the RPL and control group. There was also no significant association between the p53 codon 72 polymorphism and RPL risk in both recessive (Pro/Pro vs. Arg-carriers, p=0.314) and dominant model (Pro-carriers vs. Arg/Arg, p=0.383: data not shown)., Conclusion: The codon 72 polymorphism in the p53 gene did not show any correlation with idiopathic RPL in Korean women, implying that it may not be susceptible allelic variants or be insufficient to cause RPL., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Estrogen might play a key role in the maintenance of pregnancy. We investigated the role of the ER-β gene +1730 G/A, +1082 G/A, and CA repeat polymorphisms in Korean patients with recurrent pregnancy loss (RPL). Genotyping was performed using the TaqMan assay in 305 patients with at least two unexplained consecutive spontaneous miscarriages before 20 weeks of gestation and 299 controls. The genotype distributions of the ER-β gene +1082 G/A and +1730 G/A polymorphisms in the RPL group did not differ from those in the control group. When the analysis was restricted to patients with three or more consecutive spontaneous miscarriages, there were also no differences in the genotype distribution between this subgroup and controls. The number of CA repeats was distributed from 13 to 28 with two large peaks at 18 and 23 in patients with RPL and controls. Using the two major peaks as cut-offs, the allele distributions were compared between patients and controls. However, the distribution of ER-β gene CA repeats did not differ between women with recurrent miscarriage and controls. Findings of the current study suggest that the ER-β gene polymorphisms are not major determinants of the development of RPL in Korean women.

Problem: Thrombophilia has been postulated to be a contributor to the pathophysiology of recurrent pregnancy loss (RPL). We investigated the role of the plasminogen activator inhibitor type 1 (PAI-1) 4G/5G and angiotensin converting enzyme (ACE) I/D polymorphisms in Korean patients with RPL., Method of Study: Genotyping was performed using the TaqMan assay in 227 RPL patients and 304 controls., Results: The genotype distributions of both polymorphisms in the RPL group did not differ from those of controls. Because the frequency of being homozygous for ACE D/D and the PAI-I 4G/4G combination has been reported to be significantly higher in RPL patients, this was also analyzed. However, no significant difference was noted; 3.1% of RPL patients had both ACE D/D and PAI-I 4G/4G, as did 4.9% of controls (P = 0.791)., Conclusion: The current study suggests that both polymorphisms, either alone or in combination, are not major determinants of the development of RPL in Korean women., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: To investigate whether specific genetic polymorphisms in the cyclin-dependent kinase inhibitor 2B antisense RNA (CDKN2B-AS) gene and near the wingless-type MMTV integration site family member 4 (WNT4) gene are associated with endometriosis in a Korean population., Design: Case-control genetic association study., Setting: University., Patient(s): Surgically or histologically diagnosed cases of endometriosis (n=673) and controls (n=500) among a population of ethnic Koreans., Intervention(s): None., Main Outcome Measure(s): Genotype distribution and synergistic interaction., Result(s): Significant differences were found in the allele distributions of the CC genotype of the rs10965235 single-nucleotide polymorphism (SNP) of the CDKN2B-AS gene and the GG genotype of the rs16826658 SNP on chromosome 1p36 between the endometriosis cases and the controls (rs10965235: 69.7% CC, 26.9% CA, and 3.4% AA vs. 59.2% CC, 35.2% CA, and 5.6% AA; rs16826658: 33.7% GG, 48.4% GT, and 17.8% TT vs. 25.6% GG, 49.8% GT, and 24.6% TT, respectively). A significant interaction was not found between the CC genotype of the rs10965235 SNP and the GG genotype of the rs16826658 SNP after Bonferroni correction (32.8% of CC+GG and 67.2% of CC+non-GG in the endometriosis cases vs. 25.0% of CC+GG and 75.0% of CC+non-GG in the controls)., Conclusion(s): Our results suggest that the rs10965235 SNP in the CDKN2B-AS gene and the rs16826658 SNP near the WNT4 gene were significantly associated with endometriosis in this Korean population., (Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

Objective: Insulin resistance is a core feature of polycystic ovary syndrome (PCOS). Recently, genome-wide association studies have reported a number of single-nucleotide polymorphisms (SNPs) with reproducible associations and susceptibilities to type 2 diabetes. We examined the potential association between the diabetogenic genes uncovered in the genome-wide association studies and PCOS in Korean women., Design: Case-control study., Patients: Women with or without PCOS., Measurements: DNA samples from 377 patients with PCOS and 386 age-matched controls were genotyped., Results: None of the 12 SNPs in the six genes (KCNJ11, TCF7L2, SLC30A8, HHEX, FTO and CDKAL1) uncovered in the genome-wide association studies were associated with PCOS. For further analysis, the patients with PCOS were divided into two or three subgroups according to genotype, and the associations between the genotypes and insulin resistance or insulin secretory capacity were assessed. No SNPs were significantly associated with HOMA-IR, HOMA (βcell) (%), or 2-h 75-g oral glucose tolerance test insulin levels in the patients with PCOS; there were no significant associations with other serum hormonal and metabolic markers, such as androgen or glucose levels., Conclusions: Our results suggest that the six type 2 diabetes-associated genes identified in genome-wide association studies are not associated with PCOS., (© 2012 Blackwell Publishing Ltd.)

Background: It has been suggested that variations in the inhibin α gene (INHA) may affect the ovarian function of women. This study was performed to investigate whether the genetic polymorphisms of the INHA gene are associated with idiopathic premature ovarian failure (POF) in a Korean population., Methods: The subjects consisted of 159 idiopathic POF patients and 233 post-menopausal controls. Genotyping for the -16C>T polymorphism was performed by an minor groove binder (MGB) primer/probe Taqman assay, and the -124A>G polymorphism was identified using PCR restriction fragment length polymorphism analysis. Haplotypes were deduced by using the Haploview version 4.1., Results: There were no significant differences in the genotype distributions or allele frequencies of the INHA gene -16C>T and -124A>G polymorphisms between the POF and the control group. Haplotype analysis also showed no significant difference between groups., Conclusions: The distribution of the INHA gene promoter polymorphisms in a Korean POF population was not significantly different from controls, implying that the INHA gene polymorphisms may not be associated with the risk of idiopathic POF.

Background/aims: The aim of this study was to investigate the possibility that the K469E and G241R polymorphisms in the intercellular adhesion molecule-1 (ICAM-1) gene and the C-634G polymorphism in the interleukin (IL)-6 gene are associated with endometriosis in the Korean population., Methods: The ICAM-1 gene K469E and G241R polymorphisms and the IL-6 gene C-634G polymorphism were evaluated in 390 patients with endometriosis and 351 controls by polymerase chain reaction-restriction fragment length polymorphism analysis., Results: The ICAM-1 gene G241R polymorphism was not observed in all subjects. No differences were observed in the ICAM-1 K469E and IL-6 C-634G genotype distributions and allele frequencies between patients with endometriosis and controls. In subgroup analyses according to the stage of endometriosis or bilaterality of ovarian endometriomas, no significant differences were observed in the ICAM-1 gene K469E or the IL-6 gene C-634G polymorphism frequencies between the subgroups and the controls. The combined analysis of the ICAM-1 gene K469E polymorphism and the IL-6 gene C-634G polymorphism did not show any additional significant findings., Conclusions: The K469E and G241R polymorphisms in the ICAM-1 gene and the C-634G polymorphism in the IL-6 gene may not be genetic factors related to susceptibility to advanced-stage endometriosis in the Korean population., (Copyright (c) 2010 S. Karger AG, Basel.)