Selected nucleosides for measurement of cancer marker and detection of newly synthesized DNA and RNA.

Marker nucleosides such as 1-Methyl-adenosine, 5-Methyl-uridine, N³-methyl-uridine and Pseudouridine are found to be
elevated in assocation with cancer^{[1], [2], [3]}. Jena Bioscience offers proper nucleoside standards for their measurement.

Detection of de novo DNA synthesis or S-Phase synthesis is perfomed with modified nucleosides which are efficiently incorporated into proliferating cells and labeled subsequently. Br-dU can be tagged with the corresponding antibody ^{[4], [5], [6]}. 5-EdU will make the newly synthesized DNA visible when cells are incubated subsequently with a fluorescent azide, which is rapidly "click"-coupled to the alkyne group of 5-EdU. In contrast to Br-dU, the method does not require sample fixation or DNA
denaturation and permits good structural preservation ^{[7], [8]}. Analog 5-Ethynyl-2'-deoxy-cytidine can be used to detect DNA
synthesis with similar sensitivity as EdU ^[10].

Based on the same principle, 5-EU can be used for detection of RNA transcription and turnover in vivo. As it is incorporated into RNA transcripts, 5-EU-labeled cellular RNA can be detected quickly and with high sensitivity with fluorescent azides ^[9].

[1] Seidel et al. (2006) Modified nucleosides: an accurate tumour marker for clinical diagnosis of cancer, early detection and therapy control. Br J Cancer 94:1726.
[2] Bullinger et al. (2007) Metabolic signature of breast cancer cell line MCF-7: profiling of modified nucleosides via LC-IT MS coupling. BMC Biochem 29:25.
[3] Kim et al. (2001) Capillary electrophoretic profiling and pattern recognition analysis of urinary nucleosides from uterine myoma and cervical cancer patients. Journal of Chromatography B: Biomedical Sciences and Applications 754:97.
[4] Gratzner et al. (1992) Monoclonal antibody to 5-bromo and 5-iododeoxyuridine: a new reagent for detection of DNA replication. Science 218:474.
[5] Qin et al. (1993) Comparison of the classical autoradiographic and the immunohistochemical methods with BrdU for measuring proliferation parameters in colon cancer. Anticancer Res 13:731.
[6] Morstyn et al. (1986) Immunohistochemical identification of proliferating cells in organ culture using bromodeoxyuridine and a monoclonal antibody. J Histochem Cytochem 34(6):697.
[7] Salic et al. (2008) A chemical method for fast and sensitive detection of DNA synthesis in vivo. Proc. Natl. Acad. Sci. USA 105 (7):2415.
[8] Buck et al. (2008) Detection of S-phase cell cycle progression using 5-ethynyl-2'-deoxyuridine incorporation with click chemistry, an alternative to using 5-bromo-2'-deoxyuridine antibodies. Biotechniques 44 (7):927.
[9] Jao et al. (2009) Exploring RNA transcription and turnover in vivo by using click chemistry. Proc. Nat. Acad. Sci. USA 105 (41):15779.
[10] Qu et al. (2011) 5-Ethynyl-2'-deoxycytidine as a new agent for DNA labeling: detection of proliferating cells. Anal Biochem
417(1):112.

Please contact nucleotides@jenabioscience.com with questions or inquiries.