How to build an allogeneic hematopoietic cell transplant unit in 2016: Proposal for a practical framework.

Allogeneic hematopoietic cell transplantation is part of the standard of care for many hematological diseases. Over the last decades, significant advances in patient and donor selection, conditioning regimens as well as supportive care of patients undergoing allogeneic hematopoietic cell transplantation leading to improved overall survival have been made. In view of many new treatment options in cellular and molecular targeted therapies, the place of allogeneic transplantation in therapy concepts must be reviewed. Most aspects of hematopoietic cell transplantation are well standardized by national guidelines or laws as well as by certification labels such as FACT-JACIE. However, the requirements for the construction and layout of a unit treating patients during the acute phase of the transplantation procedure or at readmission for different complications are not well defined. In addition, the infrastructure of such a unit may be decisive for optimized care of these fragile patients. Here we describe the process of planning a transplant unit in order to open a discussion that could lead to more precise guidelines in the field of infrastructural requirements for hospitals caring for people with severe immunosuppression.

Expression of apoptosis-related oncoproteins and modulation of apoptosis by caffeine in human leukemic cells.

We investigated the modulation of radio- and chemoresistance by caffeine and mechanisms of resistance in human leukemic cell lines and mononuclear cells from 18 leukemic patients. Caffeine synergistically potentiated cytotoxicity and apoptosis induced by ionizing radiation or carboplatin (CPt), but attenuated induction of apoptosis by daunorubicin (DNR) in KG-1a cells. Since caffeine released irradiated as well as DNR-treated KG-1a cells from G2M cell cycle arrest and CPt-treated cells from S-phase arrest, this release does not fully explain the different effects of caffeine. Caffeine synergistically reduced the level of the apoptosis inhibitor glutathione after irradiation or CPt treatment. In contrast, treatment with DNR plus caffeine diminished glutathione levels to a lesser extent than DNR alone. We conclude that the effect of caffeine on glutathione depletion represents a mechanism of action by which caffeine can modulate apoptosis. Caffeine increased CPt cytotoxicity in K562 cells and its doxorubicin-resistant subline (K562/ADM), but little effect was seen in HL-60 cells or mononuclear cells from leukemic patients. Multivariate cluster analysis revealed an association of CPt resistance with the expression of c-Fos, c-N-Ras, and p53 oncoproteins and with proliferative activity (S-phase of cell cycle), but not with Bcl-2 expression.

Increased induction of apoptosis in mononuclear cells of a glucose-6-phosphate dehydrogenase deficient patient.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency belongs to the most common human disorders of metabolism. In affected patients generation of free radicals causes life-threatening hemolytic crises, for example, after consumption of certain drugs and foods or after infections. Rather than erythrocytes we analyzed mononuclear white blood cells of a patient suffering from G6PD deficiency with respect to their ability to enter apoptosis after treatment with daunorubicin, ionizing radiation, or dexamethasone. The induction of apoptosis was increased in G6PD-deficient cells compared to cells from eight normal donors. In parallel, the glutathione content of mononuclear cells from the G6PD-deficient patient was significantly decreased. While in affected patients decreased life span of erythrocytes damaged by oxidative stress has long been recognized as the mechanism underlying hemolysis, peripheral leukocytes have not received similar attention. Induction of apoptosis is a relatively complex process that has been linked to cellular glutathione content. This is the first report investigating G6PD deficiency and apoptosis.

Enhancement of semustine-induced cytotoxicity by chlorpromazine and caffeine in a human melanoma xenograft.

Chlorpromazine (CPZ) and caffeine (CFN) enhance the cytotoxicity of nitrosoureas in conventional murine tumor systems, but this effect was not confirmed in a randomized clinical trial which compared the action of semustine (MeCCNU) against the combination of MeCCNU, CPZ, and CFN. Since differences in repair systems are known to exist between cells of human or murine origin, we have employed a human melanoma xenograft system to quantify the drug interaction. The enhancement in human melanoma cells was similar to that observed with conventional murine tumor systems. Alkaline elution studies and determination of radioactivity from labeled MeCCNU pointed to increased drug retention and fixation of DNA damage as the mechanism of enhancement. Although toxicity studies were limited to murine tissues, there was evidence of increased toxicity, especially if MeCCNU was combined with both CPZ and CFN. Thus, a true therapeutic synergism may not be present for the combination. Some explanations for the failure to detect such drug interaction in clinical trials and the relevance of advanced preclinical tumor systems are discussed.

Enhancement of etoposide-induced cytotoxicity by cyclosporin A.

Following the clinical observation of enhanced antineoplastic action of etoposide in the presence of cyclosporin A (CyA), we investigated this drug interaction in several in vitro and in vivo tumor systems. Macromolecular DNA damage induced by etoposide at drug levels comparable to plasma AUC values achieved in patients was increased not only in leukemic peripheral blood cells from patients but also in mononuclear peripheral blood cells from a healthy donor. Intracellular retention of radioactivity from 3H-etoposide was increased by a factor of 1.5 at the most in the presence of CyA. The cytotoxicity of etoposide and adriamycin to L 1210 leukemic cells was clearly enhanced, whereas CyA had no effect on the action of cisplatin or ionizing irradiation. At CyA blood levels not exceeding 1.44 microgram/ml, increased tumor inhibition of etoposide was observed in a human embryonal cancer xenograft, but there was also higher lethality in normal mice. We conclude from our own data and from other recent findings that with respect to chemosensitization the effects of CyA resemble those of calcium channel blockers or anticalmodulin agents. In contrast to calcium channel blockers, however, adequate plasma levels of CyA can well be achieved in patients.

[Effect of antineoplastic agents and ionizing radiation on a human testicular cancer heterograft]. / Zur Einwirkung antineoplastischer Substanzen und ionisierender Strahlung auf ein heterotransplantiertes menschliches Hodenkarzinom.

Chemotherapy has afforded a high percentage of definitive cures in advanced testicular cancer. Nevertheless some patients with large tumor burden still succumb to chemorefractory disease. Therefore preclinical and clinical evaluation of new drugs and agents not primarily used against this type of disease are still mandatory. For preclinical drug screening purposes heterotransplantation of specific human tumors yields a model with high validity for tumor markers and drug response. Heterotransplantation of a human embryonal testicular cancer was used for simultaneous testing of established agents such as cisplatin, melphalan, bleomycin, vinblastine, etoposide and adriamycin and some newer derivatives such as PHM or mafosfamide. Furthermore agents such as procarbazine, dacarbazine and methyl-CCNU that cross the blood-brain-barrier displayed some interesting activity. The results hint at a unique chemosensitivity pattern of the xenograft line, with some accordance between clinical response to vinblastine and bleomycin and good response of the xenografts to bleomycin but not to vinblastine. Radiotherapy was also effective against this tumor line, but there was not much difference in response when the schedule of fractionation was changed. It is concluded that a combined modality approach might salvage patients with residual, chemorefractory disease.

Continuous infusion versus intermittent bolus injection of bleomycin in a human embryonal testicular cancer xenograft.

In vivo experiments with bleomycin in conventional murine tumor systems indicate a superiority of continuous-infusion schedules over daily intermittent bolus injections. This schedule of administration has been incorporated into many clinical trials, especially in testicular cancer, on the basis of in vitro and in vivo experiments as well as favorable comparisons with historical controls. Since mechanisms linked to a superiority of continuous-infusion schedules may not be operative in every individual tumor line, we have compared both schedules of administration in a human testicular cancer xenograft. We found no significant difference with respect to antineoplastic response.

Therapeutic evaluation of five nitrosoureas in a human melanoma xenograft system.

The development of nitrosoureas has switched from more lipophilic derivatives to congeners with higher water-solubility, since this property was presumably associated with a decrease in myelosuppression. We have compared the therapeutic efficacy of clinically well-known lipophilic nitrosoureas BCNU, CCNU, and MeCCNU with the recently introduced water-soluble nitrosoureas chlorozotocin (CZT) and hydroxyethyl-CNU (HeCNU), using a human melanoma xenograft system. There were considerable differences in tumor-inhibitory activity, with HeCNU ranking first and CZT last, and the rank order was similar for drug-induced lethality or bone marrow damage (in terms of reduced cellularity or macromolecular DNA damage). When the doses are expressed as percentages of the corresponding LD10/30 values, CZT ranks last and HeCNU low among conventional nitrosoureas. We conclude that water-solubility is not associated with reduced myelosuppression and that other guidelines will have to be adopted for rational development of nitrosoureas.

[Enhancement of MeCCNU potency (chemosensitization) by misonidazole in a human melanoma xenograft system]. / Anderung der Wirkstärke von MeCCNU (Chemosensibilisierung) durch Misonidazol in einem menschlichen Melanomheterotransplantatsystem.

In addition to the well-known radiosensitizing properties of misonidazole its potential for chemosensitization has been investigated recently. According to results obtained mostly with conventional murine tumor systems, the degree of such chemosensitization depends on the particular tumor system, the type of antineoplastic agent and the dose of misonidazole employed. Our experiments were conducted with a human melanoma transplanted onto (nu/nu) mice. At the dose level of 1 g/kg misonidazole toxicity was enhanced by a factor of about 3, whereas antineoplastic activity was enhanced only by a factor of about 1.8. Therefore, the usefulness of such chemosensitization remains limited, especially since under clinical circumstances this dose of misonidazole would cause unacceptable neurotoxicity. The retention of radiotivity from 14C-MeCCNU is increased in neoplastic as well as in normal tissues by a factor of 1.3.DNA interstrand crosslinks measured 24 hours after drug exposure, however, are increased by a factor of about 2. Despite their nonselective reaction at the level of molecular pharmacology, drugs with sensitizing or protective properties may well constitute a valuable addition to the serial synthesis of chemical congeners in drug development. The use of oxazaphosphorines is quoted as an example where selective protection from urotoxicity is afforded by sodium-2-mercaptoethanesulfonate.