Related Experiment Video
Updated: May 22, 2026

Quantifying the Level of 8-oxo-dG Using ELISA Assay to Evaluate Oxidative DNA Damage in MCF-7 Cells
Published on: May 24, 2024
Oxidative DNA damage correlates with cell immortalization and mir-92 expression in hepatocellular carcinoma
Romilda Cardin, Cardin Romilda1, Marika Piciocchi
1Department of Surgery, Oncology and Gastroenterology, Section of Gastroenterology, University of Padova, Via Giustiniani 2, Padova 35128, Italy.
Background:
MicroRNAs expression has been extensively studied in hepatocellular carcinoma but little is known regarding the relationship, if any, with inflammation, production of reactive oxygen species (ROS), host's repair mechanisms and cell immortalization. This study aimed at assessing the extent of oxidative DNA damage (8-hydroxydeoxyguanosine - 8-OHdG) in different phases of the carcinogenetic process, in relation to DNA repair gene polymorphism, telomeric dysfunction and to the expression of several microRNAs, non-coding genes involved in post-transcriptional regulation, cell proliferation, differentiation and death.
Methods:
Tissue samples obtained either at surgery, [neoplastic (HCC) and adjacent non-cancerous cirrhotic tissues (NCCT)] at percutaneous or laparoscopic biopsy (patients with HCV or HBV-related hepatitis or patients undergoing cholecystectomy) were analysed for 8-OHdG (HPLC-ED), OGG1 (a DNA repair gene) polymorphism (PCR-RFLP), telomerase activity, telomere length (T/S, by RT-PCR), Taqman microRNA assay and Bad/Bax mRNA (RT-PCR). Fifty-eight samples from 29 HCC patients (obtained in both neoplastic and peritumoral tissues), 22 from chronic hepatitis (CH) and 10 controls (cholecystectomy patients - CON) were examined.
Results:
Eight-OHdG levels were significantly higher in HCC and NCCT than in CH and CON (p=0.001). Telomerase activity was significantly higher in HCC than in the remaining subgroups (p=0.002); conversely T/S was significantly lower in HCC (p=0.05). MiR-199a-b, -195, -122, -92a and -145 were down-regulated in the majority of HCCs while miR-222 was up-regulated. A positive correlation was observed among 8-OHdG levels, disease stage, telomerase activity, OGG1 polymorphisms and ALT/GGT levels. In HCC, miR-92 expression correlated positively with telomerase activity, 8-OHdG levels and Bad/Bax mRNA.
Conclusions:
The above findings confirm the accumulation, in the progression of chronic liver damage to HCC, of a ROS-mediated oxidative DNA damage, and suggest that this correlates with induction of telomerase activity and, as a novel finding, with over-expression of miR-92, a microRNA that plays a role in both the apoptotic process and in cellular proliferation pathways.
More Related Videos
12:15Quantification of three DNA Lesions by Mass Spectrometry and Assessment of Their Levels in Tissues of Mice Exposed to Ambient Fine Particulate Matter
Published on: May 29, 2019
13:59A Quantitative Measurement of Reactive Oxygen Species and Senescence-associated Secretory Phenotype in Normal Human Fibroblasts During Oncogene-induced Senescence
Published on: August 12, 2018
Related Concept Videos
DNA Damage Can Stall the Cell Cycle
DNA Damage can Stall the Cell Cycle
Peroxisomes
Abnormal Proliferation
Replicative Cell Senescence
Replication in Eukaryotes
Many Proteins Orchestrate Replication at the Origin
Eukaryotic replication follows many of the same...