Smoking is the leading cause of accelerated aging and death worldwide. Therefore, identifying and intervening at smoke-responsive DNA methylation markers may be a primary way to reduce mortality risk Show more
Smoking is the leading cause of accelerated aging and death worldwide. Therefore, identifying and intervening at smoke-responsive DNA methylation markers may be a primary way to reduce mortality risk in the population. Many studies have investigated the association between smoking and DNA methylation in blood samples. Only a few studies have examined saliva and buccal cells in this regard. Here, we determined DNA methylation profiles in buccal cells from a total of 280 individuals. Epigenome-wide association analysis (N = 200) uncovered 61 CpG markers, including novel ones, that were significantly associated with smoke exposure in this tissue type. Functional analysis showed that they were overrepresented in the Wnt signaling pathway and fatty acid metabolism. We confirmed that AHRR, a known smoking marker in blood, is also a top locus in buccal cells. However, cg06036945 (p = 1.76 × 10 Show less
Facial wrinkling is a prominent sign of aging, yet individuals exhibit unique trajectories of biological aging, contributing to the variability in facial appearance. Here, we present a pioneering stud Show more
Facial wrinkling is a prominent sign of aging, yet individuals exhibit unique trajectories of biological aging, contributing to the variability in facial appearance. Here, we present a pioneering study exploring the association between lifestyle choices, DNA methylation, and SNP genotypes with a range of facial skin aging phenotypes. The study demonstrated that age-related facial skin phenotypes are influenced by multiple environmental stressors. Epigenome-wide association analyses identified differentially methylated cytosines mapped to 151 loci, including novel genes associated with facial wrinkles, such as EDAR (cg02925966, p = 4.96 × 10 Show less
Although metabolism is profoundly altered in human liver cancer, the extent to which experimental models, e.g. cell lines, mimic those alterations is unresolved. Here, we aimed to determine the resemb Show more
Although metabolism is profoundly altered in human liver cancer, the extent to which experimental models, e.g. cell lines, mimic those alterations is unresolved. Here, we aimed to determine the resemblance of hepatocellular carcinoma (HCC) cell lines to human liver tumours, specifically in the expression of deregulated metabolic targets in clinical tissue samples. We compared the overall gene expression profile of poorly-differentiated (HLE, HLF, SNU-449) to well-differentiated (HUH7, HEPG2, HEP3B) HCC cell lines in three publicly available microarray datasets. Three thousand and eighty-five differentially expressed genes in ≥2 datasets (P < 0.05) were used for pathway enrichment and gene ontology (GO) analyses. Further, we compared the topmost gene expression, pathways, and GO from poorly differentiated cell lines to the pattern from four human HCC datasets (623 tumour tissues). In well- versus poorly differentiated cell lines, and in representative models HLE and HUH7 cells, we specifically assessed the expression pattern of 634 consistently deregulated metabolic genes in human HCC. These data were complemented by quantitative PCR, proteomics, metabolomics and assessment of response to thirteen metabolism-targeting compounds in HLE versus HUH7 cells. We found that poorly-differentiated HCC cells display upregulated MAPK/RAS/NFkB signaling, focal adhesion, and downregulated complement/coagulation cascade, PPAR-signaling, among pathway alterations seen in clinical tumour datasets. In HLE cells, 148 downregulated metabolic genes in liver tumours also showed low gene/protein expression - notably in fatty acid β-oxidation (e.g. ACAA1/2, ACADSB, HADH), urea cycle (e.g. CPS1, ARG1, ASL), molecule transport (e.g. SLC2A2, SLC7A1, SLC25A15/20), and amino acid metabolism (e.g. PHGDH, PSAT1, GOT1, GLUD1). In contrast, HUH7 cells showed a higher expression of 98 metabolic targets upregulated in tumours (e.g. HK2, PKM, PSPH, GLUL, ASNS, and fatty acid synthesis enzymes ACLY, FASN). Metabolomics revealed that the genomic portrait of HLE cells co-exist with profound reliance on glutamine to fuel tricarboxylic acid cycle, whereas HUH7 cells use both glucose and glutamine. Targeting glutamine pathway selectively suppressed the proliferation of HLE cells. We report a yet unappreciated distinct expression pattern of clinically-relevant metabolic genes in HCC cell lines, which could enable the identification and therapeutic targeting of metabolic vulnerabilities at various liver cancer stages. Show less