Association between the methylations of RUNX3 in peripheral blood and lung cancer: a case-control study.

BACKGROUND: RUNX3 is hypermethylated in multiple cancers. TIMP2 also functions as a regulator of tumors. However, there are only very few reports on the association of methylation of RUNX3 and TIMP2 with lung cancer (LC) in peripheral blood. METHODS: 426 LC patients and 428 age- and sex-matched healthy controls were recruited. DNA methylation in blood was semi-quantitively assessed by mass spectrometry. For the association analysis, binary logistic regression analysis adjusted covariant was applied, and ORs were presented as per +10% methylation. RESULTS: Hypermethylation of CpG_1, CpG_5 and CpG_8 in RUNX3 was significantly associated with LC (ORs = 1.45, 1.35 and 1.35, respectively, adjusted p < 0.05), and even stage I LC. The association between the three RUNX3 CpG sites and LC was enhanced by increased age (> 55 years, ORs ranged from 1.43 to 1.75, adjusted p < 0.05), male gender (ORs ranged from 1.47 to 1.59, adjusted p < 0.05) and tumor stage (stage II&III&IV, ORs ranged from 1.86 to 3.03, adjusted p < 0.05). CONCLUSIONS: This study suggests a significant association between blood-based RUNX3 hypermethylation and LC, especially in elder people, in males and in LC patients with advanced stage.

Blood FOLR3 methylation dysregulations and heterogeneity in non-small lung cancer highlight its strong associations with lung squamous carcinoma.

BACKGROUND: Non-small cell lung cancer (NSCLC) accounts for the vast majority of lung cancers. Early detection is crucial to reduce lung cancer-related mortality. Aberrant DNA methylation occurs early during carcinogenesis and can be detected in blood. It is essential to investigate the dysregulated blood methylation markers for early diagnosis of NSCLC. METHODS: NSCLC-associated methylation gene folate receptor gamma (FOLR3) was selected from an Illumina 850K array analysis of peripheral blood samples. Mass spectrometry was used for validation in two independent case-control studies (validation I: n = 2548; validation II: n = 3866). Patients with lung squamous carcinoma (LUSC) or lung adenocarcinoma (LUAD), normal controls (NCs) and benign pulmonary nodule (BPN) cases were included. FOLR3 methylations were compared among different populations. Their associations with NSCLC clinical features were investigated. Receiver operating characteristic analyses, Kruskal-Wallis test, Wilcoxon test, logistics regression analysis and nomogram analysis were performed. RESULTS: Two CpG sites (CpG_1 and CpG_2) of FOLR3 was significantly lower methylated in NSCLC patients than NCs in the discovery round. In the two validations, both LUSC and LUAD patients presented significant FOLR3 hypomethylations. LUSC patients were highlighted to have significantly lower methylation levels of CpG_1 and CpG_2 than BPN cases and LUAD patients. Both in the two validations, CpG_1 methylation and CpG_2 methylation could discriminate LUSC from NCs well, with areas under the curve (AUCs) of 0.818 and 0.832 in validation I, and 0.789 and 0.780 in validation II. They could also differentiate LUAD from NCs, but with lower efficiency. CpG_1 and CpG_2 methylations could also discriminate LUSC from BPNs well individually in the two validations. With the combined dataset of two validations, the independent associations of age, gender, and FOLR3 methylation with LUSC and LUAD risk were shown and the age-gender-CpG_1 signature could discriminate LUSC and LUAD from NCs and BPNs, with higher efficiency for LUSC. CONCLUSIONS: Blood-based FOLR3 hypomethylation was shown in LUSC and LUAD. FOLR3 methylation heterogeneity between LUSC and LUAD highlighted its stronger associations with LUSC. FOLR3 methylation and the age-gender-CpG_1 signature might be novel diagnostic markers for the early detection of NSCLC, especially for LUSC.

Hypomethylation of DYRK4 in peripheral blood is associated with increased lung cancer risk.

Lung cancer (LC) is the leading cause of cancer-related deaths worldwide. It is urgent to identify new biomarkers for the early detection of LC. DNA methylation in peripheral blood has been reported to be associated with cancers. We conducted two independent case-control studies and a nested case-control study (168 LC cases and 167 controls in study Ⅰ, 677 LC cases and 833 controls in study Ⅱ, 147 precancers and 21 controls in the nested case-control study). The methylation levels of DYRK4 CpG sites were measured using mass spectrometry and their correlations with LC were analyzed by logistic regression and nonparametric tests. Bonferroni correction was used for the multiple comparisons. LC-related decreased DYRK4 methylation was discovered in Study I and validated in Study II (the odds ratios [ORs] for the lowest vs. highest quartile of all three DYRK4 CpG sites ranged from 1.64 to 2.09, all p < 0.001). Combining the two studies, hypomethylation of DYRK4 was observed in stage I cases (ORs per -10% methylation ranged from 1.16 to 1.38, all p < 5.9E-04), and could be enhanced by male gender (ORs ranged from 1.77 to 4.17 via interquartile analyses, all p < 0.017). Hypomethylation of DYRK4_A_CpG_2 was significantly correlated with tumor size, length, and stage (p = 0.034, 0.002, and 0.002, respectively) in LC cases. Our study disclosed the association between DYRK4 hypomethylation in peripheral blood and LC, suggesting the feasibility of blood-based DNA methylation as new biomarker for LC detection.

Aluminum Supplementation Mediates the Changes in Tea Plant Growth and Metabolism in Response to Calcium Stress.

Tea plants are more sensitive to variations in calcium concentration compared to other plants, whereas a moderate aluminum concentration facilitates the growth and development of tea plants. Aluminum and calcium show a competitive interaction with respect to the uptake of elements, consequently exerting physiological effects on plants. To further explore these interactions, in this study, we used the solution culture method to treat tea plants with two calcium concentrations (0.8 mM and 5.6 mM) and three aluminum concentrations (0 mM, 0.4 mM, and 1 mM). We then determined the influence of the combined treatments on root growth and quality compound accumulation in the tissues by a combination of phenotype, gene expression, and metabolite analyses. Moderate aluminum supplementation (0.4 mM) alleviated the inhibition of root growth caused by high calcium stress. High calcium stress significantly inhibited the accumulation of most amino acids (e.g., Glutamic acid, Citulline, and Arginine) and organic acids (e.g., a-ketoglutaric acid) in the roots, stems, and leaves, whereas aluminum deficiency significantly increased most amino acids in the roots and leaves (except Serine, Alanine, and Phenylalanine in the roots and Ser in the leaves), with a more than two-fold increase in Arg and Lysine. High calcium stress also induced the accumulation of secondary metabolites such as epigallocatechin gallate and procyanidin in the roots, whereas aluminum supplementation significantly reduced the contents of flavonol glycosides such as quercetin, rutin, myricitrin, and kaempferitrin, as well as caffeine, regardless of calcium concentration. Aluminum supplementation reversed some of the changes in the contents of leaf metabolites induced by calcium stress (e.g., 4-dihydroquercetin, apigenin C-pentoside, phenethylamine, and caffeine). Overall, calcium stress caused severe growth inhibition and metabolic disorders in tea plants, which could be reversed by aluminum supplementation, particularly in maintaining the root tips and the accumulation of secondary metabolites. These results provide a theoretical basis for improving calcium-aluminum nutrient management to promote tea plant growth and quality.

Hypomethylation of RPTOR in peripheral blood is associated with very early-stage lung cancer.

PURPOSE: Lung cancer (LC) is the leading cause of cancer-related deaths worldwide. Novel biomarkers for LC detection are urgently needed. Here we aimed to investigate the association between RPTOR methylation in peripheral blood and LC. METHODS: The methylation levels were measured by mass spectrometry in two independent case-control studies (159 LC cases vs. 188 controls in Study I, 413 LC cases vs. 687 controls in Study II). Logistic regression and Bonferroni correction were conducted to analyze the association. RESULTS: RPTOR hypomethylation was discovered in Study I and validated in Study II. Combining the two studies, RPTOR_CpG_2 and RPTOR_CpG_8 showed significantly lower methylation levels in stage I cases (ORs per -10% methylation = 1.22 and 1.27, respectively, both P-values < 0.005). The significance kept between RPTOR_CpG_8 and LC cases with tumor length ≤ 1 cm (OR per -10% methylation = 1.39, P = 0.001). Moreover, methylation levels of all CpG sites were lower in cases at stage II & III than in those at stage I (all P-values less than 0.017). CONCLUSION: Our study disclosed the association between RPTOR hypomethylation in peripheral blood and LC even in very early stage, suggesting the feasibility of blood-based DNA methylation for LC early detection.