J Clin. Biochem. Nutr., 19, 97-105, 1995 Role of Serum Enzymes in Assessing the Efficacy of Radiation Therapy for Human Carcinoma of Uterine Cervix Natarajan BALASUBRAMANIYAN,Sorimuthu SUBRAMANIAN, and Saminathan GOVINDASAMY* Departmentof Biochemistry,University of Madras, Guindy Campus, Madras-600 025, India (ReceivedMarch 29, 1995) Summary In different stages of carcinoma of the uterine cervix, the activities of serum 5'-nucleotidase, lactate dehydrogenase (LDH), phos- phohexose isomerase (PHI), ƒÁ-glutamyl transpeptidase (GGT), trans- aminases, and phosphatases were studied before and after radiation treatment. Glycolytic enzymes (LDH, PHI) were found to be increased from stage I onwards, whereas GGT, glutamate oxaloacetate trans- aminase, glutamate pyruvate transaminase, and acid and alkaline phos- phatases increased only in the advanced stages (stages III, IV), when compared with normal values. 5'-Nucleotidase was found to be increased significantly from stage II onwards when compared with the normal. The increased levels of these enzymes were reversed to near normal levels after radiotherapy. The increased levels of serum transaminases, phosphatases, and GGT in the advanced stages of carcinoma of uterine cervix may be explained on the basis of liver involvement and bone metastasis. The degree of increase in the activities of PHI and LDH may reflect the status of the cancer. The activity of 5'-nucleotidase in serum may be used as an additional marker to assess the status of carcinoma of uterine cervix under circumstances when other markers fail to provide clear indications. Key Wards: carcinoma, glycolytic enzymes, 5'-nucleotidase, trans- aminases, phosphatases The measurement of biochemical markers is being increasingly used for early diagnosis and monitoring of the progress of cancer. Derangement in the metabolic *To whom correspondence should be addressed . 97 98 N. BALASUBRAMANIYAN, S. SUBRAMANIAN, and S. GOVINDASAMY processes are often reflected in the changes of enzymatic activities. Extensive research has been conducted by numerous workers over the past few decades to find enzyme activity differences between normal and tumor cells . Many types of tumor cells secrete much larger quantities of glycolytic enzymes into the blood- stream, as a result of increased glycolytis in neoplastic cells. As a single enzyme may exhibit a similar type of changes under some non-malignant conditions, a combination of different enzyme markers is more significant and valuable than any single enzyme marker. Rao et al. [ 1 ] reported the usefulness of multiple enzyme assays in the diagnosis of various cancer cases. Phosphohexose isomerase (PHI) catalyzes the conversion of glucose-6-phos- phate to fructose-6-phosphate in the glycolytic cycle. Lactate dehydrogenase (LDH), a tetrameric enzyme composed two immunologically distinct subunits (M and H) regulates the interconversion of pyruvate and lactate, the last step of the glycolytic pathway; and this enzyme has been extensively studied and found useful in the recognition of neoplastic disease [2]. Kim et al. [3] concluded LDH activity to be a very useful marker in the diagnosis and prognosis of cancer . Roguljic et al. [4] reported a study showing that PHI, LDH, and the isoenzyme pattern of LDH in combination were very useful in distinguishing fibroadenoma from breast carcinoma. y-Glutamyl transpeptidase (GGT) is a membrane-bound glycoprotein that catalyzes the transfer of y-glutamyl groups between amino acids or peptides [5]. The physiological function of GGT is thought to be the mediation of amino acid translocation across the cell membrane [6]. Although the highest concentration of GGT is found in the brush borders of the epithelial cells that line the proximal convoluted tubules of the kidney, the enzyme has also been demonstrated in a variety of human tissues and body fluids [7]. Transaminases are an important class of enzymes linking carbohydrate and amino acid metabolism, and the study of these enzymes has established the relationships among the intermediates of the citric acid cycle. 5'-Nucleotidase is an established plasma membrane marker in many mammalian cells where the enzyme is present as an ectoenzyme [8]. Boone et al: [9] found that serum 5'-nucleotidase is almost as useful as GGT in indicating hepatobiliary disease in patients with granuloma of the liver, acute pancreatitis, congestive heart failure, rheumatoid arthritis, and carcinoma metastatic of the liver. Kim et al. [3] assessed the diagnostic value of measuring serum alkaline phosphatase, 5'-nucleotidase, GGT, and glutamate dehydrogenase activities as an aid to the detection of liver metas- tasis. Hence, in the present study we sought to correlate the activities of these enzymes in the sera of uterine cervical cancer patients with their disease status to understand their validity in diagnosis and to reassess the prognosis during the course of radiotherapy. J. Clin. Biochem. Nutr. SERUM ENZYMES IN HUMAN CARCINOMA OF UTERINE CERVIX 99 MATERIALSAND METHODS This study was conducted on patients suffering from carcinoma of the uterine cervix admitted to the Cancer Institute, Adyar, Madras, India, and the Institute of Gynecology and Obstetrics, Egmore, Madras, India. In this study, blood samples were obtained from a total number of 238 patients (30 to 60 years old) in different stages of carcinoma of the uterine cervix (stage I [group II], N=35; stage II [group III], N=70; stage III [group IV], N=115; and stage IV [group V], N=18). A total number of 125 healthy females (group I) studied were professionals and employees of different institutions without any gynecological disorders. All the patients in the present study were confirmed to have cervical cancer by cytological screening, and the stages of carcinoma were assessed by oncologists. Blood samples were also collected from groups II, III, and IV after radiation treatment. Group V patients were not included for investigation after radiation therapy as they did not respond to radiation treatment. Venous blood samples were drawn from all the subjects, and serum was separated for further analysis. The activities of glutamate oxaloacetate transaminase (SGOT) (EC. 2.6,1.6) and glutamate pyruvate trans- aminase (SGPT) (EC. 2.6.1.2) were assayed by the method of Mohur and Cook [10]. PHI (EC. 5.3.1.9) was assayed following the method of Horrocks et al [11]. The activity of serum LDH (EC. 1.1.1.27) was assayed by the method of King [12]. The activities of serum acid (EC. 3.1.3.2) and alkaline (EC. 3.1.3.1) phosphatases were assayed by the method of Moog [13] as modified by King [12]. The activity of serum GGT (EC. 2.3.2.1) was assayed according to the method of Jacobs [14]. 5'-Nucleotidase was assayed following the method of Campbell [15]. STATISTICALANALYSIS Serum LDH, PHI, GGT, SCOT, SGPT, 5'-nucleotidase, and acid and alka- line phosphatases values were expressed as the mean +SD for patients and the healthy population separately. The statistical differences were analyzed by Stu- dent's t-test, and p-value were expressed. Analysis of variance (ANOVA) was done to compare the mean levels of the parameters at different stages of carcinoma of the uterine cervix before and after radiation treatment. RESULTS The activities of serum LDH, PHI, SCOT, and SGPT, in normal and patients with carcinoma of uterine cervix before and after radiotherapy are presented in Table 1. LDH and PHI activities were found to be increased significantly (p < 0.001) in the group-II, -III, -IV, and -V patients, whereas the activities of SGOT and SGPT were increased in group-IV and -V patients only, when compared with the normal values. Group-II and -III patients showed no significant change from Vol. 19, No. 2, 1995 100 N. BALASUBRAMANIYAN, S. SUBRAMANIAN, and S. GOVINDASAMY Table 1. Activities of serum lactate dehydrogenase (LDH), phosphohexose isomerase (PHI), glutamate oxaloacetate transaminase (SCOT), and glutamate pyruvate transaminase (SGPT) in normal individuals and in patients with carcinoma of uterine cervix before and after radiotherapy. The values are expressed as IU/liter, mean±SD, with the number of individuals indicated in parentheses. p-Value: * * * <0.001, normals versus different stages of carcinoma , p-Value: +++<0 .001, before treatment versus after treatment. aSignificant difference from other groups (p<0.001). Table 2. Activities of serum acid and alkaline phosphatases, y-glutamyl transpeptidase (GGT), and 5'-nucleotidase in normal individuals and in patients with carcinoma of uterine cervix before and after radiotherapy. [be values are expressed as IU/liter, mean±SD, with the number of individuals indicated in parentheses. p-Value: * * * <0.001, normals versus different stages of carcinoma, p-Value: +++<0 .001, before treatment versus after treatment. aSignificant difference from other groups (p<0.001). normal in the level of activity of SGOT and SGPT. The activities of LDH and PHI were found to be decreased after radiation treatment from their elevated levels in stage-I, -II, and -III patients. The activities of SGOT and SGPT decreased significantly after radiation treatment in group-IV patients when compared with their pretreatment values. J. Clin. Biochem. Nutr. SERUM ENZYMES IN HUMAN CARCINOMA OF UTERINE CERVIX 101 Table 2 shows the activities of serum GGT, 5'-nucleotidase, and acid and alkaline phosphatases in normal and patients with carcinoma of uterine cervix before and after radiotherapy. The activities of GGT and acid and alkaline phosphatases were increased significantly (p<0.001) in group-IV and -V patients, but there was no significant change in their values of groups II and III when compared with normal levels. Radiotherapy resulted in the return of all these enzyme activities to near normal in group-IV patients. Radiation treatment did not produce any change in the activities of these enzymes in group-II and -III patients. The activity of 5'-nucleotidase was significantly elevated in group-III, -IV, and -V patients. After radiotherapy the enzyme activity was found to be normal in the sera of these cervical cancer patients.