Construction of A Novel Ferroptosis-related Prognostic Risk Signature for Survival Prediction in Clear Cell Renal Cell Carcinoma Patients.

PURPOSE: Targeted ferroptosis is a reliable therapy to inhibit tumor growth and enhance immunotherapy. This study generated a novel prognostic risk signature based on ferroptosis-related genes (FRGs), and explored the ability in clinic for clear cell renal cell carcinoma (ccRCC). MATERIALS AND METHODS: The expression profile of mRNA and FRGs for ccRCC patients were exacted from The Cancer Genome Atlas (TCGA) database. A ferroptosis-related prognostic risk signature was constructed based on univariable and multivariable Cox-regression analysis. Kaplan-Meier (KM) survival curves and receiver operating characteristic (ROC) curves were performed to access prognostic value of riskscore. A nomogram integrating riskscore and clinical features was established to predict overall survival (OS). Based on differentially expressed genes between high- and low-OS groups with 5-year OS, function enrichment analyses and single-sample gene set enrichment analysis (ssGSEA) were investigated to immune status. RESULTS: A 9-FRGs prognostic risk signature was constructed based on 37 differentially expressed FRGs. ROC and KM curves showed that riskscore has excellent reliability and predictive ability; Cox regression disclosed the riskscore as an independent prognosis for ccRCC patients. Then, the C-index and calibration curve demonstrated the good performance of nomogram in training and validation cohort, and its predictive ability better than other features. Immune-related biological processes were enriched by function enrichment analysis, and the immune-related cells and functions were differential by ssGSEA between high- and low-OS groups. CONCLUSION: Our study identified and verified a novel 9-FRGs prognostic signature and nomogram to predict OS, providing a novel sight to explore targeted therapy of ferroptosis for ccRCC.

Human health risks estimations from polycyclic aromatic hydrocarbons in serum and their hydroxylated metabolites in paired urine samples.

Polycyclic aromatic hydrocarbons (PAHs) are compounds with two or more benzene rings whose hydroxylated metabolites (OH-PAHs) are excreted in urine. Human PAH exposure is therefore commonly estimated based on urinary OH-PAH concentrations. However, no study has compared PAH exposure estimates based on urinary OH-PAHs to measurements of PAH levels in blood samples. Estimates of PAH exposure based solely on urinary OH-PAHs may thus be subject to substantial error. To test this hypothesis, paired measurements of parent PAHs in serum and OH-PAHs in urine samples from 480 participants in Guangzhou, a typical developed city in southern China, were used to investigate differences in the estimates of human PAH exposure obtained by sampling different biological matrices. The median PAH concentration in serum was 4.05 ng mL-1, which was lower than that of OH-PAHs in urine (8.33 ng mL-1). However, serum pyrene levels were significantly higher than urinary levels of its metabolite 1-hydroxypyrene. Concentrations of parent PAHs in serum were not significantly correlated with those of their metabolites in urine with the exception of phenanthrene, which exhibited a significant negative correlation. Over 28% of the participants had carcinogenic risk values above the acceptable cancer risk level of 10-6. Overall, estimated human exposure and health risks based on urinary 1-hydroxypyrene levels were only 13.6% of those based on serum pyrene measurements, indicating that estimates based solely on urine sampling may substantially understate health risks due to PAH exposure.