Kim Chang-Whan, Kim Jin Il, Park Soo-Heon, Han Joon-Yeol, Kim Jae Kwang, Chung Kyu Won, Sun Hee Sik
Department of Internal Medicine, College of Medicine, The Catholic University of Korea, St. Mary's Hospital, 62 Yeouido-dong, Yeongdeungpo-gu, Seoul 150-713, Korea.
Korean J Gastroenterol. 2003 Nov;42(5):387-93.
BACKGROUND/AIMS: Pyruvate kinase (PK) is a key enzyme of glycolysis. Different isoforms of this enzyme are tissue-specifically expressed (M2-PK, M1-PK, R-PK, L-PK). The concentration of the dimeric M2-PK is increased in a metabolic state of tumor cells. In this case, the dimeric M2-PK is termed Tumor M2-PK. We investigated EDTA-plasma of 73 patients with gastrointestinal (GI) cancer and 61 healthy controls to evaluate its significance in diagnosing GI cancer.
Plasma Tumor M2-PK was measured using an ELISA assay based on two monoclonal antibodies which specifically react with the dimeric Tumor M2-PK.
The sensitivity of Tumor M2-PK was 67.1% for all GI cancers, that of CA 19-9 was 38.4% and that of CEA was 34.3%. The specificity of Tumor M2-PK was 91.8% (cutoff=20 U/mL). Tumor M2-PK showed a high sensitivity in gastric cancer (62.2%), colorectal cancer (66.7%) and bile duct cancer (75.0%). In colorectal cancer, the combination of Tumor M2-PK with CEA resulted in a remarkable increase in the sensitivity (86.2%). The average Tumor M2-PK levels were generally elevated in the metastatic GI cancer patients compared to nonmetastatic patients, especially in stomach cancer with statistical significance (p=0.005).
Tumor M2-PK in EDTA-plasma seems to be a new valuable tumor marker in GI cancer.
背景/目的：丙酮酸激酶（PK）是糖酵解的关键酶。该酶的不同同工型在组织中特异性表达（M2-PK、M1-PK、R-PK、L-PK）。在肿瘤细胞的代谢状态下，二聚体M2-PK的浓度会升高。在这种情况下，二聚体M2-PK被称为肿瘤M2-PK。我们检测了73例胃肠道（GI）癌患者和61例健康对照者的乙二胺四乙酸（EDTA）血浆，以评估其在诊断GI癌中的意义。
使用基于两种单克隆抗体的酶联免疫吸附测定（ELISA）法检测血浆中的肿瘤M2-PK，这两种单克隆抗体与二聚体肿瘤M2-PK特异性反应。
肿瘤M2-PK对所有GI癌的敏感性为67.1%，癌抗原19-9（CA 19-9）为38.4%，癌胚抗原（CEA）为34.3%。肿瘤M2-PK的特异性为91.8%（临界值=20 U/mL）。肿瘤M2-PK在胃癌（62.2%）、结直肠癌（66.7%）和胆管癌（75.0%）中显示出高敏感性。在结直肠癌中，肿瘤M2-PK与CEA联合使用可使敏感性显著提高（86.2%）。与非转移性GI癌患者相比，转移性GI癌患者的肿瘤M2-PK平均水平普遍升高，尤其是在胃癌中，具有统计学意义（p=0.005）。
EDTA血浆中的肿瘤M2-PK似乎是GI癌一种新的有价值的肿瘤标志物。
