Article

Neoplastic characteristics of the DNA found in the plasma of cancer patients

Département de Physiologie végétale, Faculté des Sciences, Université de Genève, Suisse.
Oncology (Impact Factor: 2.61). 02/1989; 46(5):318-22. DOI: 10.1159/000226740
Source: PubMed

ABSTRACT About one third of patients with various malignant diseases were found to have extractable amounts of DNA in their plasma whereas no DNA could be detected in normal controls. Using the test established by one of us (M.B.), which is based on decreased strand stability of cancer cell DNA, we have found that several plasma DNA originate from cancer cells.

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    • "Serum levels of cell-free DNA have been found in many types of cancers and are usually thought to originate from apoptotic and necrotic tumor cells (Leon et al., 1977; Stroun et al., 1989). Epigenetic modification is a universal pattern in regulating gene transcription, and methylation of tumor suppressor gene promoters is the most common epigenetic mechanism in various human tumors (Bird, 1992; Jones and Laird, 1999; Herman and Baylin, 2003; Dulaimi et al., 2004; Egger et al., 2004; Jones and Baylin, 2007; Esteller, 2008). "
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    • "BRAF V600E mutation is examined in the case of a negative KRAS mutation status in several national guidelines, thus enlarging the targeted therapy–resistant patient population stratum. Significant amounts of circulating cell–free DNA (ccfDNA) are present in the plasma of cancer patients [5] [6]. As blood analysis of ccfDNA is easy to set up and relatively noninvasive, ccfDNA represents a very attractive tool for detecting the presence of mutations. "
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    • "To date, a number of studies show that plasma and serum nucleic acids can serve as both tumor-and fetal-specific markers for cancer detection and prenatal diagnosis, respectively. For example, several studies reported increased concentrations of DNA in the plasma or serum of cancer patients sharing some characteristics with DNA of tumor cells (Leon et al., 1977; Stroun et al., 1989). Interestingly, DNA levels decreased by up to 90% after radiotherapy, while persistently high or increasing DNA concentrations were associated with a lack of response to treatment (Anker et al., 2001). "
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