phosphorus-radioisotopes and Sarcoma-180

Interstitial irradiation therapy using radionuclides is a slow and continual process in which the effect is exerted gradually, thus improvement of the hypoxic status of the tumor will also take a long time. It has been known that carbogen delivery of 5-15 min increases tumor oxygenation. However, the long-term effect of carbogen breathing on hypoxic cells has not yet been determined, and little is know about the effect of carbogen breathing for sensitization to interstitial irradiation therapy.. 99mTc-HL91(99mTc 4,9-diaza-3,3,10,10-tetramethyldodecan-2,1-dione dioxime) hypoxic imaging was performed in 10 mice bearing sarcoma 180 (S180) before and after 2 h carbogen breathing. Radioactivity ratios of tumor to contralateral limbs (T/L) of the 2 images were calculated and compared. Mice bearing S180 were subjected to long-term carbogen breathing (2 h/day for 24 days), and were treated with or without 32P-colloid. Tumor growth rate was observed in the S180-bearing mice.. T/L of 99mTc-HL91 uptake before and after carbogen breathing was 1.872+/-0.391 and 1.354+/-0.189, respectively (t=4.476, P<0.01). In mice in the 32P-treated air breathing group and 32P-treated carbogen breathing group, tumor growth rate did not differ on day 12 after 32P-colloid treatment, and on day 24 the tumor volume was 2.728+/-0.469 and 2.237+/-0.603 cm3 (t=2.128, P<0.05), respectively, with tumor mass being 2.437+/-0.447 and 1.965+/-0.538 g (t=2.134, P<0.05), respectively.. Long-term carbogen breathing can increase tumor oxygenation and continual carbogen breathing is necessary for enhancing the therapeutic effect of 32P-colloid interstitial irradiation.

Topics: Animals; Brachytherapy; Carbon Dioxide; Cell Hypoxia; Mice; Mice, Inbred BALB C; Organotechnetium Compounds; Oximes; Oxygen; Phosphorus Radioisotopes; Radiation-Sensitizing Agents; Sarcoma 180

Although 32P-glass microspheres (32P-GMS) have been used in internal radiotherapy for malignant tumors, it has been one of the key obstacles to improve the effect of radiotherapy. We investigated the cellular and hypersensitive effect of combined use of low dose of cisplatin and interstitial injection of 32P-GMS on mouse solid tumor S180.. The mice with solid tumor S180 were randomly divided into four groups (controls, cisplatin therapy, 32P-GMS therapy and combination therapy). The specimens of the mice were sectioned two weeks after treatment and weighed. The death rate of tumor cells and the inhibition rate of tumor were calculated respectively. The cell cycle and apoptosis rate were evaluated with flow-cytometry. The ultrastructural changes of the four groups were observed by a transmission electron microscope. The data were analyzed by the chi-square test.. The growth of tumor was slower in the combination therapy group than in the simple therapy groups by macrography. The inhibition rate and the death rate of tumor cells of the combination therapy group were significantly higher than those of the control group and the other two simple therapy groups (P < 0.05). More cell damages were displayed in the combination therapy group than in the other groups under the light and electronic microscope.. Low-dose cisplatin combined with interstitial injection of 32P glass microspheres could be used as an effective hypersensitive regimen for the internal radiotherapy of mouse solid tumor S180.

Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Cycle; Cisplatin; Combined Modality Therapy; Female; Mice; Mice, Inbred BALB C; Microscopy, Electron, Transmission; Microspheres; Phosphorus Radioisotopes; Radiation Tolerance; Sarcoma 180

The aim of this study is to observe apoptotic changes of tumor cells in mice with the solid tumor S180 after interstitial irradiation with 32P glass microspheres.. Twenty mice with solid tumor S180 were divided into four groups. The control group was given normal saline. The experimental groups were given different doses of 32P glass microspheres (50, 150, 450uci per mouse) using interstitial implant. The terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) method was used to determine the apoptotic cells.. The mean values of the apoptotic indexes of these groups were respectively 0.39, 0.41, 0.59 and 0.95. The apoptotic indexes of the second and the third experimental groups were significantly higher than that of the control group (P < 0.05).. The interstitial irradiation with 32P glass microspheres can enhance the activity of apoptotic cells of solid tumor S180, and the effect is dose-dependent.

Topics: Animals; Apoptosis; Brachytherapy; Dose-Response Relationship, Drug; Male; Mice; Microspheres; Neoplasm Transplantation; Phosphorus Radioisotopes; Sarcoma 180

The aim of this study was to observe the changes of tumor cell apoptosis after interstitial irradiation combination with the hyperthermia treatment.. Twenty mice with solid tumor S180 were divided into four groups, including a control group which was given normal saline, and three experimental groups which were respectively applied with a hyperthermia treatment (bath water), interstitial irradiation with 32P glass microspheres, and the combined treatment of hyperthermia and interstitial irradiation. The terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) method was used to determine the final apoptotic cells.. The mean values of apoptotic indexes of these four groups were respectively 0.39, 0.53, 0.59 and 0.91. The apoptotic indexes of these experimental groups were significantly higher than that of the control group (P < 0.05). The apoptotic index of the combined treatment group was significantly higher than those of the hyperthermia group and the interstitial irradiation group (P < 0.05).. Both the interstitial irradiated with 32P glass microspheres and hyperthermia (bath water) can induce the apoptosis of mouse solid tumor S180. It seems that there is a synergistic induction of apoptosis between interstitial irradiation and hyperthermia.

Topics: Animals; Apoptosis; Brachytherapy; Combined Modality Therapy; Hyperthermia, Induced; Male; Mice; Microspheres; Neoplasm Transplantation; Phosphorus Radioisotopes; Sarcoma 180

In order to investigate the effect of internal irradiotherapy on tumor microvasculature, the vascular changes of tumor S180 following internal irradiotherapy with 32P glass microspheres were observed microscopically with vessel casts of resin perfusion and ink perfusion. The results showed that the microvessels expanded with the endothelial cells swelling and the amount of microvessels and new vessels decreased, which led to peritumoral vascular density descended. It suggests that internal irradiotherapy destroying the tumor microvasculature as external irradiation is an important influence on the efficiency of internal irradiotherapy.

Topics: Animals; Capillaries; Drug Carriers; Female; Mice; Mice, Inbred ICR; Microspheres; Phosphorus Radioisotopes; Sarcoma 180

An exonuclease that appears to represent the predominant nuclease activity in cytoplasmic extracts of sarcoma 180 ascites cells has been partially purified and characterized. The enzyme attacks RNA chains in a 5' to 3' direction, and releases 5'-mononucleotides. The initial cleavage, however, can occur at either the first, second and probably third phosphodiester linkage in some RNAs. The enzyme attacks transcripts terminated with a 5'-triphosphate more slowly than those with a 5' monophosphate, and releases a compound larger than GTP from transcripts that begin with a pppG. Capped transcripts are cleaved at least as readily as those with a 5'-P, yielding a compound larger than 7mGpppGm. The occurrence of an such an exonuclease capable of attacking capped RNAs would make it possible for mammalian cells to initiate mRNA degradation by a 5' exonucleolytic mechanism.

Topics: Animals; Cytidine Monophosphate; Cytidine Triphosphate; Cytoplasm; Exoribonucleases; Mice; Phosphorus Radioisotopes; Sarcoma 180; Substrate Specificity

Topics: Acridines; Animals; Anti-Bacterial Agents; Antimetabolites; Binding Sites; Cellulose; Dactinomycin; Daunorubicin; DNA, Neoplasm; Ethidium; Evaluation Studies as Topic; Filtration; Kinetics; Ligands; Methods; Mice; Molecular Conformation; Phosphorus Radioisotopes; Rifampin; Rifamycins; RNA, Neoplasm; Sarcoma 180

Topics: Adenine; Animals; Antineoplastic Agents; Carbon Radioisotopes; Cobalt; Cytidine; DNA, Neoplasm; Guanine; Hydrazones; Leucine; Ligands; Metals; Mice; Neoplasm Proteins; Phosphorus Radioisotopes; Pyridines; Ribonucleotide Reductases; RNA, Neoplasm; Sarcoma 180; Selenium; Semicarbazones; Sulfur; Thiosemicarbazones; Thymidine; Tritium

Topics: Animals; Cell Fractionation; Cell Nucleus; Citrates; Detergents; Male; Methods; Mice; Phosphorus Radioisotopes; RNA, Neoplasm; Sarcoma 180; Sucrose

Topics: Animals; DNA Repair; In Vitro Techniques; Light; Male; Mice; Phosphorus Radioisotopes; Radiation Genetics; RNA; Sarcoma 180; Ultraviolet Rays