L-arginine-glycine amidinotransferase, betaine-homocysteine S-methyltransferase, and neuropolypeptide H3 are diminished in renal clear cell carcinoma of humans.

OBJECTIVE To identify renal clear cell carcinoma-associated marker proteins. METHODS Twelve patients with renal cell carcinoma (RCC) were collected and processed in the Department of Urology, Renmin Hospital, Wuhan University, China, between January 2008 and September 2009. Two-dimensional polyacrylamide gel electrophoresis and matrix assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF-MS) were employed to investigate differentially expressed protein spots between RCC tissues and adjacent normal tissues, then reverse transcription polymerase chain reaction and western blot were employed to confirm the proteomic results. RESULTS One protein spot was upregulated, 13 were downregulated, and 22 were absent in RCC tissues. Four of the absent proteins were L-arginine-glycine amidinotransferase (AGAT), Betaine-homocysteine S-methyltransferase (BHMT), Ketohexokinase (KHK), and Neuropolypeptide h3 (NPh3). The reverse transcriptase-polymerase chain reaction analysis demonstrated mRNA expression of AGAT, BHMT, and Nph3 was significantly decreased in 12 RCC tissues. In addition, Western blot analysis showed AGAT protein was absent in 11/12, BHMT in 9/12, and Nph3 in 5/12 RCC tissues. CONCLUSION Absence of AGAT, BHMT, and Nph3 is common events in clear cell RCC; hence, it may be involved in the development of RCC; therefore, they have the potential to be tumor markers for diagnosis, treatment, and prognosis of RCC patients.