Lactate dehydrogenase in cerebral cyst fluids; total activity and isoenzyme distributions as an index of malignancy.

Abstract

HE chemical grading of tumors is of interest in relation to tumor diagnosis and prognosis, as well as in the field of pure oncology. Our estimations of the lactate dehydrogenase (LDH) content of cerebral tumor tissue support those of others, 6,1~ demonstrating increased amounts of LDH~, the electrophoretically slowest moving fraction or Mtype isoenzyme, in extracts of malignant tumors relative to more benign ones. Following the convention of numbering the five fractions of LDH separated by electrophoresis from 1, as the most anodic fraction, to 5 as the most cathodic fraction, this M-type of LDH, associated with anaerobic glycolysis, will be referred to as LDHs. It should be remembered when referring to the literature that there are a few authors who still use the reverse order of numbering, with the slow-moving fraction designated LDH1. The fluid that accumulates in a cystic tumor has so far received less attention than the tumor tissue. High LDH activity in a specimen of cyst fluid from a cerebral astrocytoma was reported by Green, et al., 7 in an account of LDH and transaminase activities of the cerebrospinal fluid (CSF) of patients with various neurological diseases. Szliwowski and Cumings 1~ determined LDH activity in some of the 214 cerebral cyst fluids that they examined chemically and found a tendency for the higher levels to be associated with more malignant tumors. Buckell and Robertson 2 estimated the total LDH activity in cyst fluids from 21 gliomas and 16