Quantification of XRCC and DNA-PK proteins in cancer cell lines and human tumors by LC-MS/MS.
BACKGROUND
The x-ray repair cross-complementing (XRCC) proteins and a catalytic subunit of nuclear DNA-dependent serine/threonine protein kinase (DNA-PK) play important roles in cancer biology. Understanding the protein expression levels allows us to reconstruct in vivo functionality and to qualify protein biomarkers.


RESULTS
XRCC and DNA-PK proteins in human cancer cells and tumor tissues have been identified and quantified by selected peptides using NanoLC and high-resolution mass spectrometry. The stable isotope-labeled full-length protein XRCC4 ([(13)C6, (15)N4]-arginine and [(13)C6, (15)N2]-lysine) uses as the internal standard.


CONCLUSIONS
The assay range is 0.140-450 fmol (coefficient of variation: 25%) for XRCC4 in bovine serum albumen. The quantitative protein expression levels for XRCC and DNA-PK in HeLa, Ramos and HEK-293 cells and tumor tissues (lung and lymphoma) are reported.
Celgene Corporation, Summit, NJ 07901, USA. xwang@celgene.com.
Matthew V
MV
Myers
Stephen E
SE
Maxwell
Xiaomin
X
Wang
D045744:Cell Line, Tumor; D002853:Chromatography, Liquid; D004268:DNA-Binding Proteins / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D009369:Neoplasms / Q000378:metabolism* / Q000473:pathology; D053719:Tandem Mass Spectrometry
D004268:DNA-Binding Proteins