Biology subjects

Jeong, H. Y.

Publications and source records attributed to Jeong, H. Y..

3 recordsLinked to original sources

bioRxiv2020

ASO-based PKM Splice-switching Therapy Inhibits Hepatocellular Carcinoma Cell Growth

The M2 pyruvate kinase (PKM2) isoform is upregulated in most cancers and plays a crucial role in the Warburg effect, which is characterized by the preference for aerobic glycolysis for energy metabolism. PKM2 is an alternative-splice isoform of the PKM gene and is a potential therapeutic target. Previously, we developed antisense oligonucleotides (ASOs) that switch PKM splicing from the cancer-associated PKM2 to the PKM1 isoform and induce apoptosis in cultured glioblastoma cells. Here, we explore the potential of ASO-based PKM splice-switching as a targeted therapy for liver cancer. We utilize a more potent lead cEt/DNA ASO and demonstrate that it induces PKM splice-switching and inhibits the growth of cultured hepatocellular-carcinoma (HCC) cells. This PKM isoform switch increases pyruvate-kinase activity and alters glucose metabolism. The lead ASO and a second ASO targeting a non-overlapping site inhibit tumorigenesis in an orthotopic-xenograft HCC mouse model. Finally, a surrogate mouse-specific ASO induces Pkm splice-switching and inhibits HCC growth, without observable toxicity, in a genetic HCC mouse model. These results lay the groundwork for a potential ASO therapy for HCC. Statement of significanceAntisense oligonucleotides are used to force a change in PKM isoform usage in HCC, reversing the Warburg effect and inhibiting tumorigenesis.

cancer biology↗

bioRxiv2020

Correlation-based and feature-driven mutation signature analyses to identify genetic features associated with DNA mutagenic processes in cancer genomes

Mutation signatures represent unique sequence footprints of somatic mutations resulting from specific DNA mutagenic and repair processes; however, their causal associations and potential utility for genome research remain largely unknown. In this study, we performed PanCancer-scale correlative analyses to identify the genomic features associated with tumor mutation burdens (TMB) and individual mutation signatures. We observed that TMB was correlated with tumor purity, ploidy, and the level of aneuploidy, as well as with the expression of cell proliferation-related genes representing genomic covariates in evaluating TMB. Correlative analyses of mutation signature levels with genes belonging to DNA damage-repair processes revealed that deficiencies of NHEJ1 and ALKBH3 may elevate TMB levels in cancer genomes accompanying APOBEC overactivity and DNA mismatch repair deficiency, respectively. We further employed a strategy to identify feature-driven, de novo mutation signatures and demonstrated they can be reconstructed using known causal features such as APOBEC overexpression, MLH1 underexpression, POLE mutations, and the level of homologous recombination deficiency. We further demonstrated, that tumor hypoxia-related mutation signatures are similar to those associated with APOBEC suggesting that APOBEC-related mutagenic activity mediates hypoxia-related mutational consequences in cancer genomes, and also, that mutation signatures can be further used to predict hypoxic tumors. Taken together, our study advances mutation signature-level mechanistic insights in cancer genomes, extending categories of cancer-relevant mutation signatures and their potential biological implications. Author summaryMutation signature analysis is powerful in deciphering the causative mutagenic events and their contributions in individual cancer genomes, but the causal relationship of individual mutation signatures are still largely unknown. PanCancer-scaled correlative analysis revealed mutation resource candidates in cancer genomes such as NHEJ1 and ALKBH3 deficiencies that may facilitate the accumulation of mutations in the setting of APOBEC overactivity and DNA mismatch repair deficiency, respectively. A feature-driven mutation discovery approach was employed to identify the mutation signatures representing homologous recombination deficiency and tumor hypoxia, the extent of which may serve as mutation-based phenotypic measures, previously estimated by DNA copy number alterations and mRNA expression signatures, respectively. Our study advances our understanding into the mechanistic insights of mutation signatures and proposes a method to utilize somatic mutations as a molecular proxy in terms of mutation signatures.

genomics↗

bioRxiv2019

Sarcopenia is an independent predictor of hospitalization in chronic kidney disease outpatients

BackgroundPatients with chronic kidney disease (CKD) experience much more marked and earlier muscle wasting than subjects who do not have chronic illnesses. However, a few studies that have examined sarcopenia have been reported in CKD patients. We investigated the prevalence of sarcopenia in predialysis and dialysis outpatients with CKD and explored its relationship with the clinical outcomes.\n\nMeasurementsSarcopenia was defined as reduced muscle strength accompanied by decreased adjusted appendicular skeletal muscle (ASM), while those patients who exhibited only one of these characteristics were categorized as presarcopenic patients. ASM was measured by bioimpedence analysis, and muscle strength was evaluated by handgrips. ASM was adjusted by weight (ASM/wt). Patients were prospectively followed for up to 2 years.\n\nResultsOne hundred seventy-nine patients were recruited (114 male and 65 female patients who were classified into 103 predialysis patients and 76 dialysis patients, with 44.7% having diabetes). Their mean age was 60.6 {+/-} 13.5 years old. The prevalence of sarcopenia was 9.5%, while 55.9% of the patients were categorized as presarcopenic. The ASM/wt index showed significant correlations with age, handgrip strength, HOMA-IR and frailty scores. Multivariate Cox proportional hazards models demonstrated that the risk of hospitalization was significantly higher for patients with presarcopenia [hazard ratio (HR), 2.48; 95% confidence interval (CI), 1.180-5.230], and the risk of hospitalization was much higher for patients with sarcopenia than for patients in the nonsarcopenic group (HR, 9.11; 95% CI, 2.295-25.182)\n\nConclusionsSarcopenia and presarcopenia, which were defined using the ASM/wt index and handgrip strength, predicted a poorer, hospitalization-free survival in CKD patients

scientific communication and education↗