TY - JOUR
T1 - Lactate dehydrogenase in normal mammary glands and in 7, 12-dimethylbenz[a]anthracene-lnduced mammary tumors in sprague-dawley rats
AU - Lee, Chung
AU - Oliver, Lyda
AU - Coe, Elmon L.
AU - Oyasu, Ryoichi
N1 - Funding Information:
1 Received May 9. 1978; accepted July 24. 1978. 2 Supported by Public Health Service (PHS) grant CAI4727 from the National Cancer Institute and by PHS grant RR05370 from the Division of Research Resources. National Institutes of Health. 3 Department of Urology. Northwestern University Medical School. 303 East Chicago Ave.. Chicago, III. 60611. 4 The Cancer Center. Northwestern University Medical School. , Department of Biochemistry. Northwestern University Medical School. 6 Department of Pathology. Northwestern University Medical School. 7 Isoenzyme LDH-l is defined as the band migrating farthest in the gel electrophoresis toward the anode and LDH-5 as the band migrating the least distance.
PY - 1979/1
Y1 - 1979/1
N2 - The activity of lactate dehydrogenase (LDH) and the pattern of its isoenzymes (LDH-1,-2,-3,-4, and-5) were investigated in normal and malignant mammary tissues in Sprague-Dawley rats. The total LDH activity was measured by a colorimetric method with the use of pyruvate as the substrate. LDH isoenzymes were separated by acrylamide gel electrophoresis and were measured by densitometry. Isoenzyme LDH-1 was designated as the band migrating farthest in the gel toward the anode. Mammary glands of nulliparous animals had low LDH activities, which later increased progressively during pregnancy and lactation and which were accompanied by a concurrent shift of isoenzyme pattern toward a predominance of muscle-type subunits. Involution of the mammary gland resulting from the cessation of lactation was associated with a return of LDH activities and isoenzyme patterns to the original stage. Actively growing mammary tumors induced by 7, 12-dimethylbenz[a]anth-racene showed an extremely high activity of LDH and an elevated proportion of the muscle-type subunits. Ovariectomy in the tumor-bearing animals resulted in tumor regression, which was accompanied by a reduction in LDH activity and a relative decrease in percent of the muscle-type subunits. Furthermore, unlike the normal mammary gland, in both growing and regressing mammary tumors, LDH-1 was consistently undetectable under the present experimental conditions despite a tenfold concentration of the tissue extracts. Results of this study indicated that both the LDH activity and the pattern of isoenzymes in normal and malignant mammary tissues showed characteristic changes under various endocrine states of the hosts and that the malignant transformation resulted in a loss of LDH-1 in the tissue. These characteristic LDH parameters can, therefore, be utilized as biologic markers for normal and neoplastic mammary tissues at various stages of development.
AB - The activity of lactate dehydrogenase (LDH) and the pattern of its isoenzymes (LDH-1,-2,-3,-4, and-5) were investigated in normal and malignant mammary tissues in Sprague-Dawley rats. The total LDH activity was measured by a colorimetric method with the use of pyruvate as the substrate. LDH isoenzymes were separated by acrylamide gel electrophoresis and were measured by densitometry. Isoenzyme LDH-1 was designated as the band migrating farthest in the gel toward the anode. Mammary glands of nulliparous animals had low LDH activities, which later increased progressively during pregnancy and lactation and which were accompanied by a concurrent shift of isoenzyme pattern toward a predominance of muscle-type subunits. Involution of the mammary gland resulting from the cessation of lactation was associated with a return of LDH activities and isoenzyme patterns to the original stage. Actively growing mammary tumors induced by 7, 12-dimethylbenz[a]anth-racene showed an extremely high activity of LDH and an elevated proportion of the muscle-type subunits. Ovariectomy in the tumor-bearing animals resulted in tumor regression, which was accompanied by a reduction in LDH activity and a relative decrease in percent of the muscle-type subunits. Furthermore, unlike the normal mammary gland, in both growing and regressing mammary tumors, LDH-1 was consistently undetectable under the present experimental conditions despite a tenfold concentration of the tissue extracts. Results of this study indicated that both the LDH activity and the pattern of isoenzymes in normal and malignant mammary tissues showed characteristic changes under various endocrine states of the hosts and that the malignant transformation resulted in a loss of LDH-1 in the tissue. These characteristic LDH parameters can, therefore, be utilized as biologic markers for normal and neoplastic mammary tissues at various stages of development.
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U2 - 10.1093/jnci/62.1.193
DO - 10.1093/jnci/62.1.193
M3 - Article
C2 - 102859
AN - SCOPUS:0018755489
SN - 0027-8874
VL - 62
SP - 193
EP - 199
JO - Journal of the National Cancer Institute
JF - Journal of the National Cancer Institute
IS - 1
ER -
