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Since the introduction of combined immunosuppressive therapy (IST) into management of aplastic anemia (AA) in childhood response and probability of survival improved. In contrast to bone marrow transplantation (BMT), however, patients after IST are not considered cured as high rates of relapse and development of clonal disease demonstrate. From 11/93 to 9/97 114 children (65 m, 49 f; median age 9.5 y.) from 37 centers in Germany and Austria were registered in the SAA 94 study. 86 patients lacking a matched sibling donor received IST. Most of the patients suffered from very severe (VSAA: PMN < 200/microliter) or severe AA (SAA: PMN < 500/microliter). All patients were treated with combined IST consisting of ALG and Cyclosporin A (CSA). VSAA and SAA patients were additionally treated with G-CSF. Therapy response was evaluated at day 112, after 6, 12 and 18 months. 8/86 patients died, the probability of survival being 87% after 4 years. At d 112 61% of evaluable patients became independent of transfusions (IST response: CR + PR), 13% with normal blood counts (CR). After 6 months 33% showed CR. At 12 and 18 months response improved to 74% resp. 80%, 39% resp. 55% CR. The best response was achieved in the subgroup of VSAA with 90% (PR + CR) and 65% CR after 18 months. 4 patients developed AML 3-19 months after the beginning of IST. In 2/4 pts. an aberrant clone (-7; 5q-) could be detected retrospectively in BM at diagnosis of AA. 3 nonresponders developed chromosomal aberrations (+19; -7, +12; +8) after 4, 12 and 16 months without morphological signs of AML or MDS. Overall 11 relapses occurred at a median time of 12 months (range 5-27 months) after the beginning of IST. 2 of them relapsed under CSA therapy, 2 under tapering of CSA and 7 after cessation of CSA. 7 patients responded again to CSA monotherapy. Overall response rate is 77% with a probability of event free survival (EFS) of 54% after 4 years regarding all complications mentioned as events.

Statins (3-hydroxy-3-methylglutaryl coenzyme A [HMG-CoA] reductase inhibitors) are well-established agents to treat hyperlipidemic states. Experimental and epidemiological evidence further implies an anticancer effect of these substances. This study investigates the mechanism underlying human lung cancer cell death by lovastatin and the role of the prostaglandin (PG)-synthesizing enzyme cyclooxygenase-2 (COX-2) in this process. In A549 and H358 lung carcinoma cells the lipophilic prodrug lovastatin lactone led to a concentration-dependent decrease of viability and induction of DNA fragmentation, whereas its HMG-CoA-inhibitory, ring-open acid form was inactive in this respect. Apoptotic cell death by lovastatin was accompanied by high intracellular levels of the lactone form, by upregulation of COX-2 mRNA and protein, as well as by increased formation of peroxisome proliferator-activated receptor γ (PPARγ)-activating PGD2 and 15-deoxy-Δ12,14-PGJ2. Cells were significantly less sensitive to lovastatin-induced apoptotic cell death, when the expression or activity of COX-2 was suppressed by siRNA or by the COX-2 inhibitor NS-398. Apoptosis by lovastatin was likewise reversed by the PPARγ antagonist GW9662. Fluorescence microscopy analyses revealed a lovastatin-induced cytosol-to-nucleus translocation of PPARγ that was inhibited by NS-398. Collectively, this study demonstrates COX-2 induction and subsequent COX-2-dependent activation of PPARγ as a hitherto unknown mechanism by which lovastatin lactone induces human lung cancer cell death.

1 Dimercaprol (BAL), 2,3-dimercaptopropanesulpho nate sodium (DMPS) and meso-2,3-dimercaptosucci nic acid (DMSA) are effective arsenic antidotes, but the question which one is preferable for optimal therapy of arsenic poisoning is still open to discussion. Major drawbacks of BAL include (a) its low therapeutic index, (b) its tendency to redistribute arsenic to brain and testes, for example, (c) the need for (painful) intramuscular injection and (d) its unpleasant odour. 2 The newer antidotes DMPS and DMSA feature low toxicity and high therapeutic index. They can be given orally or intravenously due to their high water solubility. While these advantages make it likely that DMPS and DMSA will replace BAL for the treatment of chronic arsenic poisoning, acute intoxication - espe cially with lipophilic organoarsenicals - may pose a problem for the hydrophilic antidotes, because their ionic nature can adversely affect intracellular avail ability. 3 This article focuses on aspects dealing with the power of BAL, DMPS, and DMSA to mobilize tissue-bound arsenic in various experimental models, such as monolayers of MDCK (=Madin-Darby canine kidney) cells from dog kidney, isolated perfused liver from guinea-pigs, and perfused jejunal segments from rat small intestine. 4 The results show that hydrophilic DMPS and DMSA may fail to rapidly and completely remove arsenic that has escaped from the extracellular space across tight epithelial barriers. However, owing to their low toxicity, which allows larger doses to be applied, and the potential modification of their pharmacokinetics by means of inert oral anion-exchange resins, DMPS and DMSA may advantageously replace BAL when ever intervention time is not critical. With severe intoxication by organic arsenicals, when the point-of- no-return is a limiting factor, BAL may still have a place as an arsenic antidote.

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