Researchers from Harbin Medical University in China compared methods for extracting cell-free DNA from serum and determined the diagnostic utility of total serum cell-free DNA and DNA integrity to detect hepatitis B virus-related hepatocellular carcinoma. As they report in Pathology, the researchers measured total serum cell-free DNA levels from 210 patients and controls using qPCR and evaluated the DNA integrity of those samples. From this, they found that the Triton/Heat/Phenol method works best for extracting cell-free DNA, and that there was no difference in total serum DNA levels between patients and controls, though patients had higher DNA integrity levels than controls. "DNA integrity is a promising molecular biomarker for detecting HCC in patients with chronic HBV infection; it reflects the progression and metastatic potential of the tumour," the researchers write.
In that same issue, Italian investigators write that the methylation status of the MGMT gene promoter could be a prognostic factor in metastatic melanoma. The researchers assessed the methylation status of 29 primary melanoma and 74 metastasis samples from 52 patients using a PCR-based approach. They report that one primary melanoma and 22 of the metastases had methylated MGMT gene promoters and that disease-free and overall survival was longer in patients with the methylated gene promoter. "We demonstrated that MGMT promoter methylation is a late event in the biological evolution of cutaneous melanoma, and that the methylation status of metastases might have a prognostic relevance in the patients' outcome, irrespective of the therapy administered," the investigators report.
Finally, researchers led by Australia's Reza Ghassemifar present a molecular tool to evaluate alpha-globin DNA variants' role in alpha-thalassemia. "We have developed an in vitro model which may be utilised to confirm or exclude a pathogenic consequence of a particular mutation," they write in Pathology. The researchers then applied their model to characterize a novel point mutation in a patent. "In this study, in vitro analysis confirmed splicing at the aberrant splice site, with a resultant frameshift and generation of a truncated protein," they add.