QUANTITATIVE BIOCHEMICAL-ANALYSIS OF SAMPLES FROM SQUAMOUS-CELL CARCINOMA

Samples of tumor, tumor stroma, and mixed tumor and stroma were microd issected from three squamous cell carcinomas, as well as from adjacent nontumor tissue and assayed for malate dehydrogenase or lactate dehyd rogenase activity as indicators of the relative contribution of aerobi c and anaerobic processes, respectively, to energy metabolism, Malate and lactate dehydrogenase activities were greater in tumor tissue than in tumor stroma in all three tumors. However, the magnitudes of malat e and lactate dehydrogenase activities were different among the tumors , suggesting that tumors vary in the degree to which aerobic and anaer obic reactions contribute to energy production. These results indicate that a quantitative assessment of enzymes involved in energy producti on may be a useful probe in the understanding of tumor metabolism.