glutaminase and Sarcoma-180

Distribution of glutamine level in different tissues of tumor bearing mice such as brain, liver, kidney, spleen, large and small intestine and the tumor itself were studied in three solid tumor models, viz, Ehrlich ascites carcinoma, Sarcoma-180 and methylcholanthrene induced carcinoma. Tumor bearing mice were subjected to therapy for 7 days with the glutaminase purified from malignant S-180 cell. The results exhibit a significant decrease in tumor burden after enzyme therapy. Host tissue glutamine levels were significantly elevated in tumor bearing untreated mice in comparison to the normal ones, while significant lower values were obtained after enzyme therapy. It therefore appears that elevated levels of glutamine in host tissue are associated with the tumor burden.

Topics: Animals; Brain; Carcinoma, Ehrlich Tumor; Glutaminase; Glutamine; Intestinal Mucosa; Kidney; Liver; Male; Methylcholanthrene; Mice; Sarcoma 180; Skin Neoplasms; Spleen; Tissue Distribution

Angiogenesis or the generation of new blood vessel, is an important factor in the growth of a solid tumor. Hence, it becomes a necessary parameter of any kind of therapeutic study. Glutamine is an essential nutrient of tumor tissue and glutamine related therapy involves clearance of circulatory glutamine by glutaminase. Therefore, using different murine solid tumor models, the present study was undertaken to find out whether the S-180 cell glutaminase has any effect on angiogenesis of solid tumor, or not. Result indicates that the purified S-180 cell glutaminase reduces tumor volume and restrict the generation of neo blood vessels. Therefore, it can be concluded that this enzyme may be an effective device against the cancer metastasis.

Topics: Angiogenesis Inhibitors; Animals; Carcinogens; Carcinoma, Ehrlich Tumor; Drug Screening Assays, Antitumor; Glutaminase; Glutamine; Injections, Intraperitoneal; Male; Methylcholanthrene; Mice; Neoplasm Proteins; Neoplasms, Experimental; Neovascularization, Pathologic; Sarcoma 180

Angiogenesis or the generation of new blood vessels, is an important factor regarding the growth of a tumor. Hence, it becomes a necessary parameter of any kind in therapeutic studies. Glutamine is an essential nutrient of tumor tissue and glutamine related therapy involves clearance of circulatory glutamine by glutaminase. So, whether this enzyme has any effect on angiogenesis of a tumor or not becomes an obvious question. To address this question, this study has been carried out with different murine tumor models. The results indicate that purified glutaminase reduces tumor volume as well as restricts the generation of new blood vessels. Glutaminase is effective in the case of solid as well as ascites tumor models. In the case of induced cancer, the host exhibits delayed onset of neoplasia following enzyme treatment and tumor host interactions determine the intensity of the neovascularisation process. Therefore, it can be concluded that this enzyme might be an effective agent against cancer metastasis.

Topics: Animals; Carcinoma, Ehrlich Tumor; Cervix Uteri; Female; Glutaminase; Glutamine; Liver; Male; Methylcholanthrene; Mice; Neovascularization, Pathologic; Neovascularization, Physiologic; Sarcoma 180; Uterine Cervical Dysplasia

High rate of glutamine use is a characteristic of tumor cell both in vivo and in vitro and experimental cancer therapies have developed by depriving tumor cells of glutamine. In several investigations, bacterial glutaminase was found to be a potent therapeutic agent against varieties of tumor, but it showed suppressive effects on haematopoietic systems and inhibitory effects on normal lymphocytic blastogenesis. No antineoplastic study has nevertheless been undertaken with glutaminase enzyme purified from mammalian source. In the present study we report the purification of glutaminase enzyme from mitochondria of highly malignant S-180 cell using ion exchange chromatography and affinity column chromatography of glutamine. Purified enzyme is a kidney type phosphate dependent glutaminase with Mr 64 KD. Effect of enzyme therapy has been investigated in transplantable as well as induced tumor model in both ascites and solid form. It has been observed that the enzyme at the total dose of 10 unit/mouse successfully inhibited the tumor burden both in ascitic and solid tumor and subsequently increases the host's life span. There was no significant toxic effect on the peripheral blood cells.

Topics: Animals; Antineoplastic Agents; Carcinoma, Ehrlich Tumor; Chromatography, Affinity; Chromatography, Ion Exchange; Glutaminase; Male; Mice; Mice, Inbred Strains; Mitochondria; Sarcoma 180; Ultracentrifugation

The short-term metabolic fate of labeled nitrogen derived from [13N]ammonia or from L-[amide-13N]glutamine was determined in murine tumors known to be resistant (Ridgeway Osteogenic Sarcoma (ROS] or sensitive (Sarcoma-180 (S-180)) to glutaminase therapy. At 5 min after intraperitoneal injection of [13N]ammonia or of L-[amide-13N]glutamine, only about 0.7% of the label recovered in both tumors was in protein and nucleic acid. After [13N]ammonia administration, most of the label (over 80%) was in a metabolized form; a large portion of this metabolized label (50-57%) was in the urea fraction with a smaller amount in glutamine (37-42%). The major short-term fate of label derived from L-[amide-13N]glutamine was incorporation into components of the urea cycle with smaller amounts in the acidic metabolites and in acidic amino acids. No labeled urea was found during in vitro studies in which S-180 tumor slices were incubated with [13N]ammonia, suggesting that the [13N]urea formed in the tumor in the in vivo experiments was not due to de novo synthesis through carbamyl phosphate in the tumor. Both tumors exhibited very low glutamine synthetase activity. Following glutaminase treatment, glutamine synthetase and gamma-glutamyltransferase activities, while remaining low, increased in the resistant tumor but not in the sensitive tumor; this increase may be related to the insensitivity of the ROS tumor toward glutaminase treatment.

Topics: Amino Acids; Ammonia; Animals; Blood Volume; Drug Resistance; Female; gamma-Glutamyltransferase; Glutamate-Ammonia Ligase; Glutaminase; Glutamine; In Vitro Techniques; Liver; Mice; Sarcoma 180; Sarcoma, Experimental; Urea

Topics: Animals; Antineoplastic Agents; Carcinoma, Ehrlich Tumor; Glutaminase; Leukemia; Leukemia, Experimental; Lymphoma; Lymphoma, Non-Hodgkin; Mercaptopurine; Mice; Neoplasms; Neoplasms, Experimental; Pharmacology; Research; Sarcoma 180; Toxicology