Carcinoembryonic proteins in gastric carcinoma metastatic to the liver.

Two cases of liver metastases from gastric carcinoma are described in which the simultaneous occurrences of alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA) and carcinoplacental alkaline phosphatase (CPALP) were demonstrated in the sera and tumor tissues. AFP was detected not only in the tumor tissues but also in the liver tissue adjacent to the tumor, while the other 2 carcinoembryonic proteins were not detected in the non cancerous liver tissues. The characteristics of CPALP in Case 1 were almost similar to the Nagao isoenzyme, based on enzyme tests involving L-leucine, L-phenylalanine and EDTA inhibitions, heat-stability and Michaelis constant, except for electrophoretical slower moving, while that in Case 2 were identical to variant type CPALP (Warnock).     

Structural Comparison of Ectopic and Normal Placental Alkaline Phosphatase

An alkaline phosphatase immunochemically similar to placental alkaline phosphatase (EC 3.1.3.1) was purified from liver metastases of a giant-cell carcinoma of the lung. Some properties of its physical and chemical structure were determined and compared to those of purified placental alkaline phosphatase. The purified tumor phosphatase and the placental phosphatase were similar with regard to the following properties: (1) NH(2)-terminal sequence, (2) peptide map, (3) subunit molecular weight, and (4) isoelectric point. The physical properties and NH(2)-terminal sequence of alkaline phosphatase isoenzyme of liver differed from the placental and the tumor enzyme. The data from the present study strongly support the hypothesis that the tumor and the placental alkaline phosphatases are products of the same gene.     

胆汁型碱性磷酸酶同工酶在恶性肝外胆道阻塞诊断中的价值

目的 探讨胆汁型碱性磷酸酶同工酶在恶性肝外胆道阻塞论断中的价值。方法 用改良琼脂糖电泳对30例健康体检者和105例肝胆疾病患者血清中的碱性磷酶同工酶（ALP）进行分离和定量分析。结果 恶性肝外胆道阻塞的胆汁型ALP显著高于非恶性肝外胆道阻塞、肝内梗阻性黄疸以及原发性肝癌,正常体验者血清中不存在胆汁型ALP;若以100U／L的胆汁型ALP区分恶性肝外胆道阻塞和其他肝胆疾病,则它对恶性外胆道阻塞的诊断灵敏度为82．9％,特异性为95％,阳性预示值为85．3％,阴性预示值为94．1％,实验总有效率为91．9％。结论 胆汁型ALP可作为恶性肝外胆道阻塞的有用诊断指标。     

Changes in neutrophil alkaline phosphatase patterns in a case of chronic myelomonocytic leukemia

In neutrophils from a 75-year-old woman suffering from chronic leukemia, an abnormal alkaline phosphatase (ALP) was observed, characterized by a significant increase in neutrophil alkaline phosphatase (NAP) activity, associated with an ectopic expression of two isoenzymes: a thermolabile ALP similar to the early placental form (or non-Regan variant), and a heat-stable isoenzyme closely related to the Nagao isoenzyme. The presence of these oncodevelopmental NAP isoenzymes in a myeloproliferative syndrome has previously not been reported.     

The accuracy of alkaline phosphatase isoenzyme determination

Alkaline phosphatase isoenzyme determination (APID) is in common use despite evidence suggesting that the results correlate poorly with actual sites of disease. To assess the predictive value of this test in clinical practice, 99 APIDs performed on 94 patients were identified and the patients' charts were reviewed. Results of APID were compared with actual patient diagnoses as determined by other means. The liver isoenzyme fraction was not very accurate in predicting the presence of liver disease (positive predictive value 68%). In contrast, the bone isoenzyme fraction was insensitive (56%) but a positive test predicted bone disease well (positive predictive value 93%). The association of elevated transaminases with elevated alkaline phosphatase on a chemistry profile was as useful as APID in identifying liver disease, suggesting that APID should not be done in this setting. Using this information, APID can be helpful in the assessment of an ill patient with an elevated alkaline phosphatase.     

Clinical value of biliary alkaline phosphatase in non-jaundiced cholangiocarcinoma

Purpose Measurement of the activities of alkaline phosphatase isoenzyme has been used for the identification and monitoring of diseases associated with the isoenzyme. Biliary alkaline phosphatase (BALP), an isoform of liver-ALP, has been found in the serum of patients with biliary obstruction and metastatic liver cancer. This study compared the BALP isoform in the serum of patients with cholangiocarcinoma (CCA) with that of non-jaundiced benign hepatobiliary disease, other cancers, and healthy persons.Methods ALP isoforms were separated using cellulose acetate electrophoresis and the activity was demonstrated using indolyl blue reagent.Results The BALP isoform was demonstrated in 65% of CCA patients independently of jaundice condition or histological grading of the tumor. The level of serum BALP in non-jaundiced CCA was significantly lower than that of jaundiced CCA, and not correlated with serum bilirubin. No BALP was detected in healthy persons. In the patients with high serum ALP (>147U/l), BALP can differentiate non-jaundiced CCA patients from other non-jaundiced carcinoma patients with 85% sensitivity, 79% specificity, and positive and negative predictive values of 81% and 83%, respectively.Conclusion The demonstration of serum BALP, in particular in non-jaundiced patients with high serum ALP, may indicate the presence of tumor in the bile duct.     

Phosphatases XII. Isoenzymes of alkaline phosphatase and radionuclear investigation (85Sr) of patients with neoplastic affection of the skeleton.

In a group of 30 patients with neoplastic processes, 13 were found to have a significantly increased serum alkaline phosphatase activity. This finding correlated with the results of investigation with 85Sr in 7 patients, but owing to a concomitant hepatal symptomatology, it proved of differential diagnostic value in only one of them. On the other hand, the activity of bone isoenzyme of alkaline phosphatase was significantly altered in 15 patients. In 14 of them the increase in bone isoenzyme activity corresponded to an X-ray and a radionuclear finding of a tumor process in the bones. This activity was within the normal range of values in only one patient with a positive result of the 85Sr investigation. An agreement between the results of determination of bone isoenzyme activity of alkaline phosphatase and those of radionuclear investigations was found in 27 patients. In addition, a correlation was established between the increased activity of bone isoenzyme and that of intestinal isoenzyme of alkaline phosphatase. Enzyme investigation can be suitably utilized, alongside radionuclear examination, for early detection of a bone process.     

Clinical value of serum alkaline phosphatase isoenzyme estimations in the elderly.

The value of the estimation of liver and bone isoenzyme of alkaline phosphatase in a series of 500 admissions to a geriatric unit is described. A raised total alkaline phosphatase was found in 40 patients and this was due to raised levels of the bone isoenzyme in about two-thirds of these. Its value in diagnosis of treatable bone disease is emphasized.     

Serum alkaline phosphatase in adult coeliac disease

The total alkaline phosphatase levels were determined in 118 patients with adult coeliac disease, 65 of whom had evidence of osteomalacia.

The secretor and blood group status, intestinal isoenzyme, and liver alkaline phosphatase played no significant part in the levels of serum alkaline phosphatase found.

There was a significant correlation between the levels of serum alkaline phosphatase and the presence of osteomalacia.

     

Prostate gland and epididymis phosphatase isoenzymes: comparisons of young adult and aged rats

Relative activities of acid and alkaline phosphatases in rat reproductive tissue were studied in young adult (10-12 months) and aged (30-34 months) rats. Prostatic alkaline phosphatase alone increased in aged animals. Moreover, prostate preparations contain two isoenzymes of alkaline phosphatase whereas only one was found in epididymal tissues. Age-associated changes in the prostatic alkaline phosphatase isoenzyme ratios were observed. No significant age-related changes in acid phosphatase tartrate sensitivity were found. Techniques for the preparation of prostate and epididymis tissue extracts are reported.     

1,25-Dihydroxyvitamin D3 exerts opposite effects on the regulation of human embryonic and nonembryonic alkaline phosphatase isoenzymes

The regulation of alkaline phosphatase activity by steroid hormones was studied in two human breast cancer cell lines, MDA-MB-157 and BT20. MDA-MB-157 cells were shown to express the alkaline phosphatase isoenzyme produced by normal breast tissue, and the activity of this isoenzyme increased 3-fold after a 72-h treatment of these cells with 10(-7) M 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3], 2-fold after treatment with 10(-6) M hydrocortisone (HC), and 5-fold after treatment with both hormones. BT20 cells did not express the isoenzyme phenotypic to breast, but ectopically expressed the isoenzyme phenotypic to term placenta and other embryonic tissue. Treatment of BT20 cells with 1,25-(OH)2D3 results in a 30% decrease in alkaline phosphatase activity of the embryonic isoenzyme. There was a 2-fold increase in activity after treatment with HC, and enzyme activity was similar to control values after treatment with both hormones. For both cell lines, changes in alkaline phosphatase activity correlated with changes in nanograms of isoenzyme per mg cellular protein, as measured by RIA. Increases in enzyme activity were inhibited when the cells were incubated simultaneously with the steroids and cycloheximide. Studies with receptors in each cell line showed that both cell lines bound 1,25-(OH)2D3 and that a 1,25-(OH)2D3-binding protein with the same mol wt as the D3 receptor was present in both. The BT20 cells also express a larger mol wt protein which binds 1,25-(OH)2D3 but is not as specific for the 1,25-(OH)2D3 isomer. HC receptors were similar in quantity and binding affinity in both cell lines.     

Alkaline phosphatase isoenzyme patterns in hyperthyroidism

Fifteen of 36 hyperthyroid patients had elevation in serum alkaline phosphatase activity. There was no difference in mean thyroxine (T4), triiodothyronine (T3), age, or duration of illness between the groups with high alkaline phosphatase and normal alkaline phosphatase levels. After treatment, serum alkaline phosphatase levels rose as T4 levels declined; at 3 months, the mean serum alkaline phosphatase value rose from 7.1 Bodansky units to 10.3 Bodansky units (P less than 0.005), while the mean T4 value fell from 18 microgram/dl to 7.2 microgram/dl (P less than 0.005). In some patients, serum alkaline phosphatase values have remained elevated for more than 1 year, despite continued normality in thyroid variables. Before therapy, isoenzyme patterns analyzed by polyacrylamide gel electrophoresis were qualitatively normal. As therapy was instituted, the isoenzyme patterns changed markedly, with increased amounts of bone alkaline phosphatase appearing in the serum as T4 levels were declining and total alkaline phosphatase was rising. Thyroid tissue homogenates from patients with Graves' disease were found to have very low levels of alkaline phosphatase activity and an isoenzyme pattern quite distinct from that found in the serum.     

Alkaline phosphatase activity in chronic streptozotocin-induced insulin deficiency in the rat: Effect of insulin replacement

Alterations in circulating alkaline phosphatase have been described in both man and the experimental animal with chronic insulin deficiency. We evaluated plasma and tissue alkaline phosphatase levels in freely-fed control, streptozotocin-induced diabetic and insulin-treated diabetic rats, seven weeks after the induction of diabetes. Circulating alkaline phosphatase activity was markedly elevated in the insulin deficient animal (p < 0.001) and completely normalized following insulin administration. The elevated plasma alkaline phosphatase activity observed in the insulin deficient animals was heat-resistant and phenylalanine-sensitive, a pattern typical of the intestinal isoenzyme. Small intestinal alkaline phosphatase activity was significantly higher (p < 0.01) in the diabetic animals, but comparable in the insulin-replaced and control rats. The intestinal isoenzyme activity was found to be strikingly insulin-sensitive; withholding insulin therapy for 36 hr prior to sacrifice resulted in an abrupt rise in both plasma and intestinal alkaline phosphatase values comparable to those observed in the insulin-deficient state. In contrast to these observations, skeletal alkaline phosphatase activity was decreased in the insulin deficient animal (p < 0.01) and this abnormality was corrected by insulin replacement. Neither insulin deficiency nor insulin replacement resulted in any significant changes in the hepatic alkaline phosphatase isoenzyme.     

Hepatocellular carcinoma and a variant alkaline phosphatase.

Four patients with hepatocellular carcinoma had a variant alkaline phosphatase that resembles the placental D-variant but is different from it in electrophoretic mobility, pH optimum, heat stability, and inhibition by phosphate. The appearance of this enzyme has been specific to hepatocellular carcinoma. Its prevalence was about 30%, while that of another marker protein, alpha-fetoprotein was 77%. The occurrence of this enzyme in serum of patients with hepatoma was, accordingly, independent of the serum alpha-fetoprotein concentration, and also independent of the appearance of the Regan or the Nagao isoenzymes and of the serum alkaline phosphatase activity. Patients with the enzyme had a massive type of hepatocellular carcinoma with grade III differentiation by Edmondson's classification. The detection of this enzyme in serum may be of help in confirming the diagnosis of hepatoma.     

Perspectives on alkaline phosphatase isoenzymes

Since 1959, electrophoretic technics have ushered in the era of isoenzymes with a proliferation of methods and new findings. This is an attempt to develop a perspective on alkaline phosphatase isoenzymes from both fundamental and applied points of view.Thus, in addition to the bone source, isoenzymes of alkaline phosphatase from liver, intestine and placenta have now been found to contribute importantly to the serum, either individually, or in combination. It is now possible to distinguish each of these from the others in mixtures and to quantitate them by either a combination of specific inhibitors and heat inactivation or urea denaturation or by the employment of a variety of electrophoretic technics in which isoenzyme bands can be identified by their sensitivity to specific inhibitors or their reactivity to specific anti-serums.Particularly helpful in the fractionation of these isoenzymes has been the use of organ-specific inhibitors such as L-phenylalanine and L-homoarginine. In turn, their study has provided new insights into the mechanism of uncompetitive inhibition.The appearance of new forms of alkaline phosphatase during development and an appreciation of developmental control mechanisms has been paralleled by hormone enhancement of activity in cells (HeLa) growing in culture. The role of alkaline phosphatase in fat absorption and in placental function has now become a subject of interest, and the interrelationship with genetic factors such as blood groups has been recognized. The appearance of new forms during development is now accepted.The classic question of whether or not the liver is able to generate a major contribution of alkaline phosphatase to the circulation is still being investigated.Finally, an exciting direction is the study of the recently discovered placental forms of alkaline phosphatase in the tumor tissue, body fluids and serum of certain cancer patients. From the clinical point of view, tumor alkaline phosphatase may explain certain hyperphosphatasemias in problems of differential diagnosis, and from the biological perspective, this phenomenon can be studied profitably as an example of embryonic gene activation in cancer.     

Extracellular alkaline phosphatase in the airways of the rabbit lung

In an attempt to characterize the soluble alkaline phosphatase in rabbit lung, we have compared its activity to that of intestine, liver, bone, kidney, spleen and serum. The pulmonary alkaline phosphatase consists of isoenzymes with isoelectric points (pI) at pH 5. 0, 5. 5 and 5. 8 which are distinct from the soluble isoenzymes of the other tissues and, by this criterion, appear to be organ specific. The isoenzyme with a pI of 5. 8 has an apparent molecular weight of 185, 000 daltons and is found almost exclusively extracellularly in the airways. The isoenzyme with a pI of 5. 5 (mol. wt. = 185, 000 daltons) is distributed more equally between pulmonary tissue and the airways, and the isoenzyme of pI equal to 5. 0 (mol. wt. = 210, 000 daltons) is located entirely within the lung tissue. The isoenzymes present in the airways are closely related in spite of their different isoelectric points. In addition to their apparent molecular weights, they have similar apparent K_m values and thermostabilities. The difference in isoelectric points is probably due to different sialic acid contents since digestion of the two alkaline phosphatases in the airways with neuraminidase gives rise to a single form with a pI of 7. 6.     

A variant alkaline phosphatase found in a case of gastric carcinoma with super bone scan.

A rare case of gastric carcinoma associated with increased serum variant alkaline phosphatase activities is presented. A 54 year old man had extremely high serum alkaline phosphatase activity (18,607 U/l) with normal calcium and phosphate concentrations. His bone scintigram showed abnormal findings, 'super bone scan'. He was diagnosed as having Borrmann type 4 gastric carcinoma with diffuse bone metastases by examinations of the upper gastrointestinal tract and iliac bone biopsy. The alkaline phosphatase isozyme of this patient was of the bone type as measured by cellulose acetate membrane electrophoresis and the placenta/bone type by agarose gel electrophoresis, respectively. Immunoelectrophoresis and the immunoprecipitation method using monoclonal antibodies against various alkaline phosphatase isozymes, however, showed that his serum alkaline phosphatase had the liver type antigenicity. Furthermore, it had a larger molecular size and different sugar chains compared with the common liver type alkaline phosphatase. These findings suggest that a unique variant alkaline phosphatase was produced by gastric cancer cells, which is possibly an explanation for the high serum alkaline phosphatase activities in this patient.     

High serum alkaline phosphatase level revealing a liver adenoma

A 25-year-old woman had a high serum level of alkaline phosphatase activity (2571 UI/L). Serum levels of transaminases, gamma glutamyl transferase and bilirubin were normal. Abdominal ultrasonography revealed a tumor nodule in the right liver lobe. There was no evidence of biliary obstruction. The serum activity of alkaline phosphatase returned to normal after surgical removal of the liver tumor. Histologic examination showed that the tumor was a liver adenoma with no evidence of degeneration. The adenoma cells reacted strongly positive to alkaline phosphatase by histochemical staining. The production of hepatic and biliary type alkaline phosphatase by the tumor is the most likely mechanism for the high serum levels observed in this patient.     

Intestinal alkaline phosphatase in patients with liver disease

Electrophoretic separation of the different isoenzymes of alkaline phosphatase was done, using polyacrylamide gel electrophoresis. In some patients with liver disease, two isoenzymes of alkaline phosphatase were detected—one corresponding to liver and the other, to intestinal fraction. In 17 of 51 patients with nutritional cirrhosis and in 6 of 14 with chronic active hepatitis, the intestinal band was observed in their fasting sera. Intestinal isoenzyme was not found, however, in the fasting sera of 23 patients with viral hepatitis, 16 with metastatic disease to the liver, 11 with obstructive jaundice or 33 healthy volunteers. The presence of intestinal isoenzyme was not dependent on the value of total serum phosphatase activity.Supported in part by Grant IN-27L P/4 from the American Cancer Society, grants from the Kelsey-Leary Foundation of Houston, and Grants RR 134 and 350 from the General Clinical Research Centers Program of the Division of Research Resources, National Institutes of Health.Presented in part at the meeting of the Southern Section of the American Federation for Clinical Research, New Orleans, Louisiana, January 1971.     

Intestinal alkaline phosphatase in bile: evidence for an enterohepatic circulation.

The isoenzyme characteristics of alkaline phosphatase in human bile obtained from patients with gallstones have been determined by means of electrophoresis on polyacrylamide gel, both before and after preincubation with neuraminidase, and also by means of inhibition tests with heat, urea, and L-phenylalanine. Bile alkaline phosphatase is shown to be partly secreted by the liver cell, but partly derived from the small intestine. The presence of small-intestinal alkaline phosphatase in bile implies an enterohepatic circulation of this high molecular weight glycoprotein. The significance of this finding is discussed in relation to the mechanism whereby large protein molecules may pass across the plasma membrane of the liver cell.