Tumor type M2 pyruvate kinase expression in gastric cancer, colorectal cancer and controls.
OBJECTIVE
Tumor formation is generally linked to an expansion of glycolytic phosphometabolite pools and aerobic glycolytic flux rates. To achieve this, tumor cells generally overexpress a special glycolytic isoenzyme, termed pyruvate kinase type M(2). The present study was designed to evaluate the use of a new tumor marker, tumor M(2)-PK, in discriminating gastrointestinal cancer patients from healthy controls, and to compare with the reference tumor markers CEA and CA72-4.


METHODS
The concentration of tumor M(2)-PK in body fluids could be quantitatively determined by a commercially available enzyme-linked immunosorbent assay (ELISA)-kit (ScheBo Tech, Giessen, Germany). By using this kit, the tumor M(2)-PK concentration was measured in EDTA-plasma of 108 patients. For the healthy blood donors a cut-off value of 15 U/mL was evaluated, which corresponded to 90% specificity. Overall 108 patients were included in this study, 54 patients had a histological confirmed gastric cancer, 54 patients colorectal cancer, and 20 healthy volunteers served as controls.


RESULTS
The cut-off value to discriminate patients from controls was established at 15 U/mL for tumor M(2)-PK. The mean tumor M(2)-PK concentration of gastric cancer was 26.937 U/mL. According to the TNM stage system, the mean tumor M(2)-PK concentration of stage I was 16.324 U/mL, of stage II 15.290 U/mL, of stage III 30.289 U/mL, of stage IV 127.31 U/mL, of non-metastasis 12.854 U/mL and of metastasis 35.711 U/mL. The mean Tumor M(2)-PK concentration of colorectal cancer was 30.588 U/mL. According to the Dukes stage system, the mean tumor M(2)-PK concentration of Dukes A was 16.638 U/mL, of Dukes B 22.070 U/mL, and of Dukes C 48.024 U/ml, of non-metastasis 19.501 U/mL, of metastasis 49.437 U/mL. The mean tumor M(2)-PK concentration allowed a significant discrimination of colorectal cancers (30.588 U/mL) from controls (10.965 U/mL) (P<0.01), and gastric cancer (26.937 U/mL) from controls (10.965 U/mL) (P<0.05). The overall sensitivity of tumor M(2)-PK for colorectal cancer was 68.52%, while that of CEA was 43.12%. In gastric cancer, tumor M(2)-PK showed a high sensitivity of 50.47%, while CA72-4 showed a sensitivity of 35.37%.


CONCLUSIONS
Tumor M(2)-PK has a higher sensitivity than markers CEA and CA72-4, and is a valuable tumor marker for the detection of gastrointestinal cancer.
Zhang
Bo
B
Department of General Surgery, Affiliated Xiehe Hospital of Huazhong University of Science and Technology, Wuhan 430022, Hubei Province, China. wavestor@whu.edu.cn
Chen
Jian-Ying
JY
Chen
Dao-Da
DD
Wang
Guo-Bin
GB
Shen
Ping
P
D014408:Biomarkers, Tumor / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000201:enzymology* / Q000473:pathology* / Q000556:secondary; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D009367:Neoplasm Staging; D011770:Pyruvate Kinase / Q000378:metabolism*; D012680:Sensitivity and Specificity; D013274:Stomach Neoplasms / Q000201:enzymology* / Q000473:pathology* / Q000556:secondary
D014408:Biomarkers, Tumor; D011770:Pyruvate Kinase