Changes of LDH-isozymes, esterases, acid phosphatases and proteins in malignant and benign human brain tumors

Novel methods to diagnose leptomeningeal metastases in breast cancer

Leptomeningeal metastases (LM) in breast cancer patients are rare but often accompanied by devastating neurological symptoms and carry a very poor prognosis, even if treated. To date, two diagnostic methods are clinically used to diagnose LM: gadolinium MRI of the brain and/or spinal cord and cytological examination of cerebrospinal fluid (CSF). Both techniques are, however, hampered by limited sensitivities, often leading to a long diagnostic process requiring repeated lumbar punctures and MRI examinations. To improve the detection rate of LM, numerous studies have assessed new techniques. In this review, we present the current workup to diagnose LM, set out an overview of novel techniques to diagnose LM, and give recommendations for future research.

Lactate dehydrogenase isoenzymes of human semen

1. A lactate dehydrogenase isoenzyme present in human spermatozoa and semen was isolated and characterized biochemically in term of its pH for optimum activity and by means of K(m) values for lactate, NAD(+) and NAD analogues. The results were compared with those obtained with the human heart-type and the liver-type lactate dehydrogenase isoenzymes. 2. The enzyme was characterized by its resistance to digestion with different proteolytic enzymes. The time for 50% digestion in terms of residual dehydrogenase activity was compared with times obtained for the H(4)- and M(4)-types.

Metabolic patterns in malignant gliomas

Changes of mitochondrial and cytoplasm tumor metabolism were studied in malignant gliomas and normal cortex probes in vitro. By spectrophotometric methods marker enzymes of different mitochondrial (whole respiratory chain, citrate acid cycle, fatty oxidation) and cytoplasm (glycolysis, pentose phosphate shunt) metabolic energy pathways were analysed. Generally, the activities of intramitochondrial key enzymes were significantly decreased in gliomas when compared with enzyme activities of normal cortex tissue (p < 0.01). Glycolytic enzymes and a representative of the pentose phosphate shunt were unchanged or increased. Ratios of marker enzymes of the glycolytic pathway (lactate dehydrogenase) and glycose-6-P dehydrogenase revealed a significant difference between glioblastomas (p < 0.05) and grade III (p < 0.05) tumors in comparison to normal astrocytic tissue and astrocytomas WHO grade II. Thus, biochemical analyses allow metabolic grading of gliomas in vitro and may be a useful tool for understanding tumor biology.

Histologic and histochemical changes in experimental carcinomas following cryosurgery

Histologic and histochemical changes in experimental SCCs following cryosurgery were reported. Effects of cryosurgery on SCCs of hamster cheek pouch were classified into 3 zones; the superficial zone was the cryodestructive layer on which the cryoprobe had been attached directly to the SCC; the zone beneath this layer was the indirect cryodestructive layer; the 3rd zone was unaffected tissue in which the critical low temperature was never reached. In the superficial cryodestructive layer, tumor cells were destroyed completely and bleeding was found in the stroma. In the zone beneath it, neoplastic cells also showed morphologic and enzymatic changes indicating incomplete cellular destruction; dilatation of capillary vessels was also found. LDH isozyme pattern displayed a high level of LDH 5 in the non-treated SCC, and following cryosurgery, the high level of LDH 5 decreased and revealed an approximately normal LDH 5 pattern.

Supernumerary lactate dehydrogenase isozymes in human gliomas

Supernumerary bands in agarose gel electrophoresis of lactate dehydrogenase (LDH) were frequently observed in extracts of human gliomas. The supernumerary fractions which migrated cathodic to LDH-2 and/or cathodic to LDH-3 were designated LDH-2' and LDH-3'. These extra bands were clearly seen in certain gliomas and less distinctly in others, being more frequent in primitive or undifferentiated tumours. The extra bands seen in gliomas differ from the LDH-X of the testis, but LDH-2' seemed correspond to LDH-Z in placenta, hydatidiform mole, and choriocarcinoma. These sub-bands are interpreted as being produced by gliomas and as oncofetal enzymes.

Lactic dehydrogenase isoenzymes in the cerebrospinal fluid of patients with systemic cancer

Lactic dehydrogenase (LDH) isoenzymes were measured in the cerebrospinal fluid (CSF) patients suffering a variety of cancer-related neurologic problems. LDH-5 isoenzyme as a percentage of total LDH activity was abnormally elevated (above 10 to 15%) in leptomeningeal infiltration by carcinoma (breast carcinoma, lung carcinoma, and malignant melanoma) but not in other types of CNS metastases. Abnormal LDH isoenzyme patterns were also seen with CSF infections in which a granulocytic pleocytosis was present. In the absence of infection, an elevated LDH isoenzyme 5:1 ratio suggested leptomeningeal tumor and, when used with other CSF markers (beta-glucuronidase and CEA), LDH, isoenzymes aid in early detection of this metastatic neoplastic process. They may also help to differentiate leptomeningeal tumor from other chronic meningitides. Measurement of CSF markers also aids in assessing the effectiveness of treatment since marker levels often vary with the clinical course.

Unusually high creatine kinase BB isoenzyme and study of lactate dehydrogenase pattern in metastatic adenocarcinoma of the prostate

We report a case of metastatic adenocarcinoma of the prostate with widespread bony and hepatic involvement having extremely high BB isoenzyme of creatine kinase in serum (2405 U/liter). The serum LD5/LD1 ratio is greater than one, with total LD activity more than twenty-five fold the normal value. The homogenate of prostate gland of the patient shows an extra band with electrophoretic mobility between MM and MB isoenzymes of creatine kinase and highly elevated LD5 fraction compared to LD1 (33% vs. 9%), a remarkable LD isoenzyme pattern of malignant prostate tissue.

Clinical enzymology in cancer

It is fair to say that so far, and with few exceptions, the application of enzymology to clinical oncology has been disappointing. This is certainly true with regard to cancer screening and diagnosis. It is unlikely that any single enzyme or isoenzyme will emerge as a sufficiently sensitive or specific indicator of cancer, and it would seem more profitable to focus on multivariate or pattern analysis of several enzymes and other measurable body fluid constituents. Another suggested approach would be to establish the normal enzyme levels for individuals and then follow them for changes which might signal the development of a neoplasm. Finally, Weber's concept of key enzymes as the phenotypic markers of neoplasia and targets of chemotherapy would appear to open a new avenue for enzymology in clinical oncology.

Changes in lactate dehydrogenase isoenzyme patterns in patients with tumours of the central nervous system.?

The total activities of lactate dehydrogenase (LD) and the LD isoenzyme distribution were determined on homogenates from 61 benign and malignant intracranial tumours, and in serum and cerebrospinal fluid from 45 and 28 of the tumour patients respectively. The LD activity and the LD isoenzyme distribution in serum were not changed in patients with intracranial tumours. The LD activity in the cerebrospinal fluid was raised in about 50% of the tumour patients, but without any significant differences between patients with benign and malignant tumours. Except for very low activities in acoustic schwannomas and in pituitary adenomas, the tumour tissue did not differ significantly from normal brain in total LD activity. The LD isoenzyme distribution showed a pronounced cathodal shift in the grade 3-4 astrocytomas and the metastatic carcinomas, but an anodal shift in the grade 1-2 astrocytomas and the oligodendrogliomas. The meningiomas and the ocoustic schwannomas showed a midzone isoenzyme pattern with a dominant LD3 fraction. Knowledge of the LD isoenyme distribution can thus sometimes be a complement to the histological examination in the classification of brain tumours.

Lactate dehydrogenase (LD), hydroxybutyrate dehydrogenase (HBD), and LD-isoenzymes in brain tissue

The total activities of lactate dehydrogenase (LD) and hydroxybutyrate dehydrogenase (HBD), and the LD isoenzyme distribution were determined in tissue samples taken in vivo from different parts of the rabbit brain, and in cortical grey, subcortical white, and cerebellar tissue from man. The total LD and HBD activities were found to be higher in the brain stem than in the cerebral hemisphere, basal ganglia, and cerebellum of the rabbit brain. The isoenzyme distribution in the brain stem and the cerebellum showed an anodal shift, i.e., significantly higher activities of LD1 compared with the cerebral hemisphere and the basal ganglia. In man the total LD activity was found to be lower in white than in grey matter, although the isoenzyme patterns did not differ. The implications of these findings in relation to the LD isoenzyme pattern in serum after traumatic brain injury are discussed.