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We report a 31-year-old female who had repeated thrombosis and was diagnosed as having congenital homozygous protein C deficiency based on decreased protein C antigen and activity, and the findings of family history. This patient had shown no symptom of thrombosis until the age of 27 years, when she had cerebral infarction as the first symptom. Low molecular weight heparin was useful for disseminated intravascular coagulation (DIC) that complicated protein C deficiency in this patient.

A 70-year-old man was admitted to our hospital because of paraplegia. A spinal epidural tumor (Th VII-XI) was diagnosed by magnetic resonance imaging and resected. Histological examination of the tumor showed non-Hodgkin's lymphoma of the diffuse large cell type (Lymphoma Study Group classification), with a B cell phenotype. The clinical stage was IEA by the Ann Arbor classification. Radiation therapy of the involved field was performed (total dose : 40Gy), followed by six courses of modified cyclophosphamide, adriamycine, vincristine, prednisolone (CHOP) therapy. He was discharged walking unaided 10 months later and has shown no evidence of relapse in the 26 months since discharge.(Internal Medicine 31 : 513-515, 1992)

Isolated rat lens was punctured with a needle at a single point in the equatorial region and was incubated at 37 degrees C. Spermidine/spermine N1-acetyltransferase activity was increased about 5-fold at 8 h after the puncture. Concomitantly, putrescine content in the lens increased markedly at 8-16 h after the puncture, while spermidine levels were slightly depressed. Pretreatment of the lens with actinomycin D or cycloheximide blocked the increases of spermidine/spermine N1-acetyltransferase activity and putrescine content. Ornithine decarboxylase, on the other hand, was not induced to a detectable degree by this stimulus and 5 mM difluoromethylornithine could not block the increase of putrescine content. Polyamine oxidase showed a relatively constant activity that was sufficient for the metabolism of newly formed N1-acetylspermidine. These results suggested that, in the punctured lens, the polyamine levels were regulated predominantly by the activity of spermidine/spermine N1-acetyltransferase, but not by the induction of ornithine decarboxylase.

Methylglyoxal bis(3-aminopropyl-amidinohydrazone) (MGBA), methylglyoxal bis(4-aminobutyl-amidinohydrazone) (MGBT), methylglyoxal bis(cyclohexyl-amidinohydrazone) (MGBC) and methylglyoxal bis(butyl-amidinohydrazone) (MGBB) were synthesized as potent competitive inhibitors for polyamine biosynthetic enzymes. Four compounds competitively inhibited S-adenosylmethionine decarboxylase. Ornithine decarboxylase was also inhibited by MGBA, MGBT and BGBB competitively with ornithine. Furthermore, MGBC and MGBB inhibited spermidine synthase competitively with the substrate putrescine. All the compounds showed anti-proliferative effects on human leukemia Molt4B cells. The intracellular contents of putrescine, spermidine and spermine analyzed in MGBB-treated Molt4B cells, were shown to be depressed simultaneously. These results suggest that the combination of effective moieties in a single inhibitor molecule affecting different enzymic steps of the pathway would provide an efficient way to block the metabolic pathways.

Methylglyoxal bis(butylamidinohydrazone) (MGBB) inhibited S -adenosylmethionine decarboxylase (SAMDC) activity competitively with S -adenosylmethionine (SAM) showing the K i value of 1.8 × 10 −5 M. MGBB showed less SAMDC-stabilizing effect in rat liver in vivo than did methylglyoxal bis(guanylhydrazone) (MGBG). MGBB inhibited the growth of human erythroid leukemia K 562 cells. Putrescine, spermidine and spermine concentrations in MGBB-treated cells were depressed to 56%, 58% and 88% of the values of control cells, respectively. [ 35 S]Methionine incorporation into trichloroacetic acid-insoluble fraction was decreased in the inhibitor-treated cells.

Cirsiliol and AA861, specific arachidonate 5-lipoxygenase inhibitors, showed potent antiproliferative effects on human leukemic cell lines K562, Molt4B and HL60. On the other hand, HeLa cells were not affected by these drugs. In the inhibitor treated and growth retarded leukemia cells, the rates of synthesis of DNA, RNA and protein were markedly decreased. These results suggested that arachidonate 5-lipoxygenase or leukotrienes would play essential roles in cellular functions of leukemic cells.

Methylglyoxal bis(3-aminopropylamidinohydrazone (MGBA) inhibited S-adenosylmethionine decarboxylase (AdoMetDC) activity competitively with S-adenosylmethionine (AdoMet), showing a Ki value of 2.60 x 10(-5) M. It also inhibited ornithine decarboxylase competitively with ornithine, showing a Ki value of 3.80 x 10(-5) M. MGBA inhibited the growth of human erythroid leukemia K562 cells. Putrescine, spermidine, and spermine concentrations in MGBA-treated cells were depressed to 19%, 36%, and 66% of the values of control cells, respectively.

Effects of methylglyoxal bis(butylamidinohydrazone) (MGBB), a reversible inhibitor of ornithine decarboxylase (ODC) and S-adenosylmethionine decarboxylase (AdoMetDC), on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced increases of ODC and AdoMetDC activities, ODC and mRNA level and polyamine contents in mouse skin were investigated in connection with tumor formation. Formation of papillomas by applications of TPA to 7,12-dimethylbenz[a]anthracene (DMBA)-initiated mouse skin was effectively inhibited by simultaneous topical applications of MGBB, MGBB also dose-dependently inhibited the ability of TPA to induce increases of ODC activity, ODC mRNA level and the accumulation of putrescine and spermidine in mouse skin. Induction of AdoMetDC activity was not affected by the drug. These inhibitory effects of MGBB on ODC induction and tumor promotion were more evident in multiple application experiments than with a single application of the drug.

Ornithine decarboxylase (ODC) was induced in the liver, lung and brain of the mouse injected intraperitoneally with 12- 0 -tetradecanoyl-phorbol 13-acetate (TPA), showing maximal enzyme activity four hours after the injection. The increase of ODC activity was due to the enhanced syntheses of mRNA and protein. The induction of ODC activity by TPA was specifically blocked by methylglyoxal bis(butylamidino-hydrazone) (MGBB), a competitive inhibitor of ODC and S -adenosyl-methionine decarboxylase, but not by the analog methylglyoxal bis(guanylhydrazone) (MGBG).

N -Chlorosulfonyl dicyclohexylamine (CSD) was synthesized as a potent inhibitor of spermidine synthase and analyzed for antiproliferative effects on leukemic cells. The compound specifically inhibited spermidine synthase in a competitive mode with the substrate putrescine (Ki, 1.8 × 10 −7 M). When human leukemia Molt4B cells were cultured in the presence of the inhibitor, the intracellular level of spermidine and the rate of cell proliferation were markedly depressed. In these polyamine depleted and growth retarded cells the synthesis of protein, but not of DNA or RNA, was found to be significantly diminished.

1. 1. Polyamine oxidase was purified from the soluble fraction of porcine liver by more than 70,000-fold to electrophoretic homogeneity using N8-acetylspermicline-Sepharose 4B affinity chromatography. 2. 2. The molecular weight and isoelectric point of this enzyme were 62,000 and pH 4.5, respectively. 3. 3. Optimal pH for the catalytic activity was close to 10.0. 4. 4. The enzyme activity was enhanced by 5 mM dithiothreitol or 5 mM benzaldehyde. 5. 5. Preferential substrates for this cytoplasmic PAO were N1-acetylspermine, N1-acetylspermicline and spermine. 6. 6. Spermidine was not virtually the substrate for this enzyme. 7. 7. The present results suggested the physiological roles of cytoplasmic PAO, being coupled with the reaction of spermidine/spermine N1-acetyltransferase, in recycling the cellular polyamines to putrescine.

A patient with an intracranial embryonal carcinoma, which was resistant to cisplatin-based combined chemotherapy and radiotherapy, developed spinal seeding. Alpha fetoprotein (AFP), human chorionic gonadotropin (HCG) and the beta chain of HCG (NCG beta) in serum or cerebrospinal fluid immediately returned to elevated levels despite sequential chemotherapy and resection. Accordingly, we treated this patient with spinal irradiation and intensive combination chemotherapy (cisplatin etoposide, vinblastine, cyclophosphamide and actinomycin D) followed by autologous bone marrow transplantation. With this treatment, the clinical manifestations showed a tendency to improve and, furthermore, the serum levels of AFP and HCG returned to normal. These findings suggest autologous bone marrow transplantation to be a potential approach to the treatment of patients with embryonal carcinomas.

The activities of ornithine decarboxylase (ODC) and spermidine/spermine N 1 -acetyltransferase (SAT) were increased by the addition of S -adenosylmethionine decarboxylase (AdoMetDC) inhibitor methylglyoxal bis(guanylhydrazone) (MGBG) in cultured human erythroid leukemia K 562 cells. ODC activity began to increase 4hr after the addition of the drug and attained a maximum at 12 hr. The increase of SAT activity lagged behind that of ODC activity. The increases of both ODC and SAT activities produced by MGBG were blocked by treatment with cycloheximide, suggesting that the increase of enzyme activity resulted from the synthesis of new enzyme proteins. The putrescine content in cells treated with MGBG increased markedly, whereas the levels of spermidine and spermine were depressed lower. On the other hand, methylglyoxal bis(butylamidinohydrazone) (MGBB), a derivative of MGBG inhibiting AdoMetDC effectively, did not induce ODC or SAT activities.