A BIOCHEMICAL STUDY OF TUMOR GROWTH AND ITS EFFECT ON UNINVOLVED TISSUES OF THE HOST
Tumor growth was studied in the rat 5A mammary carcinoma and 3M2N squamous cell mammary carcinoma, as well as a human mesothelioma being serially transplanted in nude mice. Enzyme concentrations were measured to determine if their level would change as the growth rate of the tumors decreased. Thymidine kinase (TK), uridine kinase (UK), and/or phosphoserine phosphatase (PSP) concentrations were found to decrease as the volume doubling time (DT) of the tumors increased with increasing time since transplantation and increasing tumor weight. The mitotic rate of the 5A tumor was also shown to decrease with increasing DT and there was no increase in the amount of necrosis at the outer surface of the tumor with decreasing growth of the tumor. In human tumors the levels of TK, UK and/or PSP were shown to be positively correlated to the DT, loss of differentiation and mitotic rate. The concentration of UK was further shown to be related to the cell type and cell of origin of tumors. It was at higher than expected concentrations in the carcinoid and oat cell carcinomas, which are both of neural crest origin. The effect of tumors on uninvolved tissues was also studied in rat and human lungs. The metastatic-free lungs of rats bearing 5A tumors were found to have increased in weight by 24%. This weight increase was due to an increase in cellularity, as seen in photomicrographs and confirmed by an increase in the total amount of lung DNA. The concentrations of PSP, alkaline phosphatase and (gamma)-glutamyl transpeptidase were also increased, suggesting an increase in the growth potential of the lung tissue caused by a blood-born tumor factor(s). In humans the normal lung adjacent to the tumors had higher levels of UK, PSP, and peptidyl proline hydroxylase (PPH) than tissue distant from the tumors. Also, the amount of macrophages in the human lungs were correlated to the degree of fibrosis and the concentration of PPH.
HEAD, JONATHAN FREDERICK, "A BIOCHEMICAL STUDY OF TUMOR GROWTH AND ITS EFFECT ON UNINVOLVED TISSUES OF THE HOST" (1985). ETD Collection for Fordham University. AAI8521391.