Cytosine arabinoside(AraC) inhibits DNA synthesis and beta-DNA polymerase, an enzyme involved in DNA repair. This a potent antimitotic agent, is clinically used as an anticancer drug with side effect of severe neurotoxicity. Earlier reports suggested that inhibition of neuronal survival by AraC in sympathetic neuron may be due to the inhibition of a 2'-deoxycytidine-dependent process that is independent of DNA synthesis or repair and AraC induced a signal that is triggers a cascade of new mRNA and protein synthesis, leading to apoptotic cell death in cultured cerebellar granule cells. The present study would suggest whether caspase family(ICE/CED-3-like protease) involved in AraC-induced apoptosis pathway of PC12 cells. It was observed that treatment of PC12 cells with AraC led to decrease of viability by MTT assay and morphology changes, which did not suggest that AraC induced apoptosis in PC12 cells. The mRNA of caspase-1/caspase-3 were expressed in PC12 cells constitutively, and AraC did not activate caspase family. These results suggest that caspase-1/caspase-3 may not be required for AraC-induced cell death pathway in PC12 cells.
Animals ; Apoptosis ; Cell Death ; Cytosine* ; DNA ; DNA Repair ; Humans ; Neurons ; PC12 Cells* ; RNA, Messenger

The cAMP-dependent protein kinase(PKA) is an intracellular enzyme with serine-threonine kinase activity that plays a key role in cell growth, differentiation, and apoptosis in eukaryotes. In order to understand the PKA signal transduction pathway regulating cell life cycle and identify its role, we focused on the characterization of up-/down-regulated genes by PKA using the differential display polymerase chain reaction. Seven differentially expressed sequence tags(DEST) have been obtained. Among these DESTs, 2DESTs were homologous to the sequence of genes from BLAST search result. KC1-5 DEST that was up-regulated in A123.7 cells was highly corresponded to mouse apoptosis-related gene(MA-3) or mouse mRNA for topoisomerase inhibitor suppressed(TIS). MA-3 was induced in various types of apoptosis, specially in NGF-deprived apoptotic PC12 cells, TIS was down-regulated in the RVC lymphoma cells incubated with topoisomerase inhibitor that induces DNA strand breakages. PG1-1DEST that was highly expressed in PC12 cells was corresponded to transposon Tn103'-end. Tnansposon Tn10 was up-regulated in differentiated myeloblastic ML-1 cells by 12-O-tetradecanoylphorbol-13-acetate. This study illuminates that MA-3/TIS was down-regulated by PKA activity, and transposon Tn10 was up-regulated by it.
Animals ; Apoptosis ; DNA ; Eukaryota ; Granulocyte Precursor Cells ; Life Cycle Stages ; Lymphoma ; Mass Screening* ; Mice ; PC12 Cells* ; Polymerase Chain Reaction ; Protein-Serine-Threonine Kinases ; RNA, Messenger ; Signal Transduction

Anthrax toxin consists of three separate proteins, protective antigen (PA), edema factor (EF), and lethal factor (LF). PA binds to the receptor on mammalian cells and facilitates translocation of EF or LF into its cytosol. PA is the primary component of anthrax vaccines. In this study we purified PA from culture filtrates of Bacillus anthracis. The purification involved sequential chromatography through hydroxylapatite, DEAE-Sepharose CL-4B, followed by Mono-Q. The purified PA was judged to be homogeneous on SDS-PAGE, and consisted of a single polypeptide chain with a relative molecular weight of 85,000.
Anthrax ; Anthrax Vaccines ; Bacillus anthracis* ; Bacillus* ; Chromatography ; Cytosol ; Durapatite ; Edema ; Electrophoresis, Polyacrylamide Gel ; Molecular Weight

PURPOSE: The purpose of this study was to evaluate the efficacy of curative radiotherapy in the management of supraglottic cancer. MATERIALS AND METHODS: Twenty-one patients with squamous cell carcinoma of the supraglottis were treated with radiotherapy at Gyeongsang National University Hospital between 1990 and 1994. Median follow-up period was 36 months and 95% were observed for at least 2 years. RESULTS: Actuarial survival rate at 5 years was 39.3% for 21 patients. The 5-year actuarial survival rate was 75.0% in Stage I, 42.9% in Stage II, 33.3% in Stage III, and 28.6% in Stage IV (p=0.54). The 5-year local control rate was 52.0% for 21 patients. The 5-year local control rate was 75.0% in Stage I, 57.1% in Stage II, 66.7% in Stage III, and 28.6% in Stage IV (p=0.33). Double primary cancer was developed in 3 patients and those were all esophageal cancers. CONCLUSION: In early stage (Stage I and II) supraglottic cancer, curative radiotherapy would be a treatment of choice and surgery would be better to be reserved for salvage of radiotherapy failure. In advanced stage (Stage III and IV), radiotherapy alone is inadequate for curative therapy and combination with surgery should be done in operable patients. This report emphasizes the importance of esophagoscopy and esophagogram at the follow-up of patients with supraglottic cancer.
Carcinoma, Squamous Cell ; Esophageal Neoplasms ; Esophagoscopy ; Follow-Up Studies ; Humans ; Radiotherapy* ; Survival Rate

PURPOSE: The purpose of this study was to evaluate the efficacy of curative radiotherapy in the management of supraglottic cancer. MATERIALS AND METHODS: Twenty-one patients with squamous cell carcinoma of the supraglottis were treated with radiotherapy at Gyeongsang National University Hospital between 1990 and 1994. Median follow-up period was 36 months and 95% were observed for at least 2 years. RESULTS: Actuarial survival rate at 5 years was 39.3% for 21 patients. The 5-year actuarial survival rate was 75.0% in Stage I, 42.9% in Stage II, 33.3% in Stage III, and 28.6% in Stage IV (p=0.54). The 5-year local control rate was 52.0% for 21 patients. The 5-year local control rate was 75.0% in Stage I, 57.1% in Stage II, 66.7% in Stage III, and 28.6% in Stage IV (p=0.33). Double primary cancer was developed in 3 patients and those were all esophageal cancers. CONCLUSION: In early stage (Stage I and II) supraglottic cancer, curative radiotherapy would be a treatment of choice and surgery would be better to be reserved for salvage of radiotherapy failure. In advanced stage (Stage III and IV), radiotherapy alone is inadequate for curative therapy and combination with surgery should be done in operable patients. This report emphasizes the importance of esophagoscopy and esophagogram at the follow-up of patients with supraglottic cancer.
Carcinoma, Squamous Cell ; Esophageal Neoplasms ; Esophagoscopy ; Follow-Up Studies ; Humans ; Radiotherapy* ; Survival Rate

The Bcl-2 protein has been shown to block apoptosis induced by a variety of stimuli. We have performed the experiments which cell death can be blocked by the bcl-2 proto-oncogene under moderate(50-100mM) or high ethanol treatment(400-600mM). As a result of morphological changes, and MTT assay, cell death was blocked by Bcl-2 under 100mM ethanol. However, the results of DNA fragmentation and RT-PCR(ICE, and CPP32), immunoblotting(CPP32, and PARP) for SK-pcDNA3 cells(vector only) and SK-Bcl-2 cells(stably expressed bcl-2 gene) were showen to be no significant differences between two cell lines. These result suggested that cell death induced by ethanol was not followed by apoptosis mechanism, and was blocked by the bcl-2 proto-oncogene with moderate ethanol.
Apoptosis ; Cell Death* ; Cell Line ; DNA Fragmentation ; Ethanol* ; Ice ; Proto-Oncogenes*

Baerobic, spore forming, and rod-shaped bacterium. Anthrax spores are introduced into macrophage by phagocytosis and multiply after germination. The anthrax spores infected in macrophage produce lethal toxin eventually caused cell death. In this study, we analyzed apoptosis and cytokine TNF-alpha and IL-12 secretion after the infection of spores of B. anthracis Sterne in the murine macrophage RAW264.7 cells and in the primary human macrophages. In murine macrophage RAW264.7 cells infected by spore of B. anthracis Sterne, the cells were markedly changed in secretion of TNF-alpha (482~6,213 pg/ml) by lethal toxin, and induced apoptosis. In case of RAW264.7 cells infected by formalin-inactivated spores of B. anthracis, the cells were not able to produce lethal toxin, which released lower level concentration of TNF-alpha (7.7~97.2 pg/ml), and rarely induced apoptosis. When primary human macrophage cells infected with spores of B. anthracis Sterne, they secreted TNF-alpha (5~16 pg/ml), and induced apoptosis about 1% of total cells. We presented that inducing apoptosis by spores of B. anthracis Sterne capable of expressing lethal toxin is related with the secretion of TNF-alpha in murine macrophage RAW264.7 cells. These studies revealed that human and murine macrophages has affected differently by anthrax lethal toxin produced by spores of B. anthracis Sterne.
Anthrax ; Apoptosis ; Bacillus anthracis* ; Bacillus* ; Cell Death ; Germination ; Humans ; Interleukin-12* ; Macrophages* ; Phagocytosis ; Spores* ; Tumor Necrosis Factor-alpha*

Bacillus anthracis is a soil pathogen capable of causing anthrax in animals and humans. To establish a method for specifically detecting B. anthracis, we used nested polymerase chain reaction. Outer and inner sets of oligonucleotide primers were designed from the protective antigen (pag) gene and from the cya gene of the plasmid pXO1. Ainplification of 482 bp or 208 bp DNA fragment obtained from a nested PCR method provided the basis for rapid and reliable assay for the detection and identification of B. anthracis.
Animals ; Anthrax ; Bacillus anthracis* ; Bacillus* ; DNA ; DNA Primers ; Humans ; Plasmids ; Polymerase Chain Reaction* ; Soil

PURPOSE: To evaluate the role of curative radiotherapy and salvage surgery in patients with T1,T2 glottic cancer. MATERIALS AND METHOD: Between June 1989 and December 1994, 23 patients with early glottic cancer, 18 with T1N0M0 and 5 with T2N0M0, were treated with radiotherapy at Gyeongsang National University Hospital. All patients were male. Median follow-up period was 46 months, and 100% were observed for at least 3 years. RESULTS: Actuarial survival rates at 5 years were 84.3% for 23 patients. The 5-year actuarial survival rates were 94.4% for T1 and 53.3% for T2 (P=0.05). The 5-year local control rates was 70.0% for T1 and 60.0% for T2 (P=0.44). Of 8 patients with treatment failure, 6 patients (75.0%) were salvaged with surgery. After surgical salvage, the 5-year local control rates were 87.2% for T1 and 80.0% for T2(p=0.55). CONCLUSION: In early stage (Stage I and II) glottic cancer, curative radiotherapy can be a treatment of choice and surgery reserved for salvage of radiotherapy failure.
Follow-Up Studies ; Humans ; Male ; Radiotherapy* ; Survival Rate ; Treatment Failure

We studied the T lymphocyte and its subpopulation percentage change in 40 patients immediately after the radiation therapy. Study population consisted of 12 patients treated at the site of head and neck region, 14 patients treated at the site of thoracic region, and 14 patients treated at the site of pelvic region. Twenty two patients received radiotherapy as radical modality, and remaining 18 patients received radiotherapy as postoperative modality. Immediately after radiotherapy, total T lymphocyte (T1) percentage was decreased from 36.4% to 34.1%, but suppressor T lymphocyte (T8) percentage was increased from 23.5% to 25.4%. As a result, T4/T8 ratio was decreased from 1.57 to 1.39. This study suggested that immediate change after radiotherapy of the T lymphocyte and its subpopulation percentage was not related to the treatment volume and the degree of helper T cell decrement was not pronounced by the radiation does increment. Longterm follow-up study in larger scale is needed to determine long term changing pattern in T lymphocyte subpopulation and its relationship to the prognosis of patients.
Antibodies, Monoclonal* ; Head ; Humans ; Lymphocyte Subsets* ; Lymphocytes* ; Neck ; Pelvis ; Prognosis ; Radiotherapy*