The expression of ketohexokinase is diminished in human clear cell type of renal cell carcinoma.
For identification and targeting of tumor-associated marker proteins, the proteome of clear cell type of renal cell carcinoma (RCC) and normal kidney tissues was analyzed by 2-DE. Ketohexokinase (also called fructokinase), which catalyzes the phosphorylation of fructose to fructose 1-phosphate, was identified by MALDI-TOF MS and found to be expressed at low rates in the renal tumor tissues. We found a decreased amount of ketohexokinase mRNA in RCC compared to that observed in the normal kidney tissues by Northern blot. The activity of ketohexokinase in 20 clear cell RCC specimens and the 20 corresponding normal kidneys was investigated, and its activity was shown to be approximately 1.4-fold lower in the RCC specimens than in the normal kidney. Ketohexokinase activity in tumor stage pT3 RCC was 1.5-fold lower than in pT1 RCC. The level of ketohexokinase activity in histological grade 3 RCC was 1.8-fold lower than that in grade 1 cancer. In addition, using in situ hybridization, it was revealed that ketohexokinase in the normal kidney tissue was confined to the proximal tubular epithelial cells, while the expression of ketohexokinase in RCC tissues was extremely low. Our research results show that the expression of human ketohexokinase was diminished in clear cell RCC.
Hwa
Jeong Seok
JS
Department of Urology, College of Medicine and Institute of Health Science, Gyeongsang National University, Jinju, South Korea.
Kim
Hyun Joon
HJ
Goo
Bo Mee
BM
Park
Hyo Jin
HJ
Kim
Choong Won
CW
Chung
Ky Hyun
KH
Park
Hyung Chul
HC
Chang
Se-Ho
SH
Kim
Yeon Woong
YW
Kim
Deok Ryong
DR
Cho
Gyeong Jae
GJ
Choi
Wan Sung
WS
Kang
Kee Ryeon
KR
D018262:Adenocarcinoma, Clear Cell / Q000201:enzymology* / Q000473:pathology; D014408:Biomarkers, Tumor / Q000378:metabolism*; D015152:Blotting, Northern; D002292:Carcinoma, Renal Cell / Q000201:enzymology* / Q000473:pathology; D005631:Fructokinases / Q000235:genetics / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007668:Kidney / Q000378:metabolism; D007680:Kidney Neoplasms / Q000201:enzymology* / Q000473:pathology; D020543:Proteome / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
D014408:Biomarkers, Tumor; D020543:Proteome; D012333:RNA, Messenger; D005631:Fructokinases; C021475:ketohexokinase