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Purpose: To determine whether the levels of circulating microRNAs (miRNAs) are altered in patients undergoing thermal ablation and chemoembolization and whether these changes are predictive of a clinical outcome.Material and Methods: This prospective study consisted of 43 patients diagnosed with hepatocellular carcinoma (n = 15) and intrahepatic colorectal cancer metastases (n = 28) treated with thermal ablation (n = 23; radiofrequency [n = 6] or microwave [n = 19]), chemoembolization using drug-eluting embolics (n = 18), or both (n = 2). Four blood samples (immediately before the intervention and 60-90 minutes, 24 hours, and 7 days after the intervention) were taken to measure the plasma concentrations of miRNAs related to hypoxia (miR-21 and miR-210), liver injury (miR-122), epithelial-mesenchymal transition (miR-200a), and apoptosis (miR-34a) using miRNA-specific TaqMan assays and quantitative real-time polymerase chain reaction. Tumor burden and treatment response at 3 months were evaluated using the modified response evaluation criteria in solid tumors. The miRNA results were compared with clinical outcomes (Mann-Whitney U test, Wilcoxon matched-pair test).Results: Dynamic changes in the circulating miRNA levels were observed following both the interventions. For thermal ablation, significant increases in miR-21, miR-210, miR-122, miR-200a, and miR-34a concentrations peaked 60-90 minutes after the intervention (P < .01). However, for transarterial chemoembolization, maximum increases in the miRNA concentrations were observed at 24 hours after the intervention for miR-21, miR-210, miR-122, miR-200a, and miR-34a (P < .05). The increased concentrations of the circulating miRNAs were followed by a subsequent decline to baseline by 7 days. For the thermal ablation (but not chemoembolization) patients, elevations in the miR-210 and miR-200a levels were associated with early progressive disease at 3 months (P = .040 and P = .012, respectively).Conclusions: Increased but dynamic levels of circulating miRNAs are present following interventional oncologic procedures and may prove useful as biomarkers for the monitoring of clinical outcomes. [ABSTRACT FROM AUTHOR]

The RECQ4 protein belongs to the RecQ helicase family, which plays crucial roles in genome maintenance. Mutations in the RECQ4 gene are associated with three insidious hereditary disorders: Rothmund–Thomson, Baller–Gerold, and RAPADILINO syndromes. These syndromes are characterized by growth deficiency, radial ray defects, red rashes, and higher predisposition to malignancy, especially osteosarcomas. Within the RecQ family, RECQ4 is the least characterized, and its role in DNA replication and repair remains unknown. We have identified several DNA binding sites within RECQ4. Two are located at the N-terminus and one is located within the conserved helicase domain. N-terminal domains probably cooperate with one another and promote the strong annealing activity of RECQ4. Surprisingly, the region spanning 322–400 aa shows a very high affinity for branched DNA substrates, especially Holliday junctions. This study demonstrates biochemical activities of RECQ4 that could be involved in genome maintenance and suggest its possible role in processing replication and recombination intermediates. [ABSTRACT FROM AUTHOR]