Browsing by Author "Chen, Ka"

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    Genetic variants in PDSS1 and SLC16A6 of the ketone body metabolic pathway predict cutaneous melanoma-specific survival.
    (Molecular carcinogenesis, 2020-06) Dai, Wei; Liu, Hongliang; Chen, Ka; Xu, Xinyuan; Qian, Danwen; Luo, Sheng; Amos, Christopher I; Lee, Jeffrey E; Li, Xin; Nan, Hongmei; Li, Chunying; Wei, Qingyi
    A few single-nucleotide polymorphisms (SNPs) have been identified to be associated with cutaneous melanoma (CM) survival through genome-wide association studies, but stringent multiple testing corrections required for the hypothesis-free testing may have masked some true associations. Using a hypothesis-driven analysis approach, we sought to evaluate associations between SNPs in ketone body metabolic pathway genes and CM survival. We comprehensively assessed associations between 4196 (538 genotyped and 3658 imputed) common SNPs in 44 ketone body metabolic pathway genes and CM survival, using a dataset of 858 patients of a case-control study from The University of Texas M.D. Anderson Cancer Center as the discovery set and another dataset of 409 patients from the Nurses' Health Study and the Health Professionals Follow-up Study as the replication set. There were 95/858 (11.1%) and 48/409 (11.7%) patients who died of CM, respectively. We identified two independent SNPs (ie, PDSS1 rs12254548 G>C and SLC16A6 rs71387392 G>A) that were associated with CM survival, with allelic hazards ratios of 0.58 (95% confidence interval [CI] = 0.44-0.76, P = 9.00 × 10-5 ) and 1.98 (95% CI = 1.34-2.94, P = 6.30 × 10-4 ), respectively. Additionally, associations between genotypes of the SNPs and messenger RNA expression levels of their corresponding genes support the biologic plausibility of a role for these two variants in CM tumor progression and survival. Once validated by other larger studies, PDSS1 rs12254548 and SLC16A6 rs71387392 may be valuable biomarkers for CM survival.
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    Genetic Variants in RUNX3, AMD1 and MSRA in the Methionine Metabolic Pathway and Survival in Non-small Cell Lung Cancer Patients.
    (International journal of cancer, 2019-01-16) Chen, Ka; Liu, Hongliang; Liu, Zhensheng; Luo, Sheng; Patz, Edward F; Moorman, Patricia G; Su, Li; Shen, Sipeng; Christiani, David C; Wei, Qingyi
    Abnormal methionine dependence in cancer cells has led to methionine restriction as a potential therapeutic strategy. We hypothesized that genetic variants involved in methionine-metabolic genes are associated with survival in non-small cell lung cancer (NSCLC) patients. Therefore, we investigated associations of 16,378 common single-nucleotide polymorphisms (SNPs) in 97 methionine-metabolic pathway genes with overall survival (OS) in NSCLC patients using genotyping data from two published genome-wide association study (GWAS) datasets. In the single-locus analysis, 1,005 SNPs were significantly associated with NSCLC OS (P < 0.05 and false-positive report probability < 0.2) in the discovery dataset. Three SNPs (RUNX3 rs7553295G>T, AMD1 rs1279590G>A and MSRA rs73534533C>A) were replicated in the validation dataset and their meta-analysis showed that adjusted hazards ratio [HR] of 0.82 [95% confidence interval (CI) =0.75-0.89] and Pmeta =2.86 x 10-6 , 0.81 (0.73-0.91) and Pmeta =4.63 x 10-4 , and 0.77 (0.68-0.89) and Pmeta =2.07 x 10-4 , respectively). A genetics score of protective genotypes of these three SNPs revealed an increased OS in a dose-response manner (Ptrend <.0001). Further expression quantitative trait loci (eQTL) analysis showed significant associations between these genotypes and gene mRNA expression levels. Moreover, differential expression analysis further supported a tumor-suppressive effect of MSRA, with lower mRNA levels in both lung squamous carcinoma and adenocarcinoma (P <.0001 and <.0001, respectively) than in adjacent normal tissues. Additionally, low mutation rates of these three genes indicated the critical roles of these functional SNPs in cancer progression. Taken together, these genetic variants of methionine-metabolic pathway genes may be promising predictors of survival in NSCLC patients. This article is protected by copyright. All rights reserved.