Monocyte-derived dendritic cells display a highly activated phenotype and altered function in patients with familial Mediterranean fever.

Dendritic cells (DCs) are sentinels of the immune system that bridge innate and adaptive immunity. By capturing antigens in peripheral tissue, processing and presenting them with concurrent expression of co-stimulatory molecules and cytokine secretion they control and modulate immune reactions. Through pattern recognition receptors, DCs sense molecules that are associated with infection or tissue damage, frequently resulting in the formation of inflammasomes upon intracellular stimulation. The inherited autoinflammatory familial Mediterranean fever (FMF) is associated with deregulated activity of the pyrin inflammasome leading to acute inflammatory episodes. However, differentiation and function of DCs in this disease are as yet unclear. Therefore, we first determined DC subpopulation frequency in peripheral blood of a cohort of FMF patients. Joint evaluation without classification according to specific patient characteristics, such as mutational status, did not disclose significant differences compared to healthy controls. For the further examination of phenotype and function, we used immature and mature monocyte-derived DCs (imMo-DCs, mMo-DCs) that were generated in vitro from FMF patients. Immunophenotypical analysis of imMo-DCs revealed a significantly elevated expression of CD83, CD86 and human leukocyte antigen D-related (HLA-DR) as well as a significant down-regulation of CD206, CD209 and glycoprotein NMB (GPNMB) in our FMF patient group. Furthermore, FMF imMo-DCs presented a significantly higher capacity to migrate and to stimulate the proliferation of unmatched allogeneic T cells. Finally, the transition towards a more mature, and therefore activated, phenotype was additionally reinforced by the fact that peripheral blood DC populations in FMF patients exhibited significantly increased expression of the co-stimulatory molecule CD86.

[Surgical staging of lung cancer]. / Thoraxchirurgisches Staging des Lungenkarzinoms.

Proper staging of lung cancer represents the basis for any stage-adapted and optimized treatment. This is today implemented in specialized centers mainly through the use of modern imaging methods and minimally-invasive measures. However, general thoracic surgery has a role not only in the therapeutic management of lung cancer, but offers additional staging information whenever endoscopic or interventional methods fail to achieve representative tissue biopsies of mediastinal lymph nodes or suspect lesions for conclusive diagnosis. The thoracic surgical armentarium comprises of cervical or extended mediastinoscopy, video-assisted mediastinal lymphadenectomy (VAMLA), anterior mediastinotomy (Chamberlain procedure) and video-thoracoscopy (VATS). Indications for any invasive diagnostic methods always have to respect a therapeutic benefit for the patient.

Resistance to EGFR targeting therapies in lung cancer.

The treatment of advanced non-small cell lung cancer (NSCLC) by therapies targeting the epidermal growth factor receptor (EGFR) pathway represents one of the most important advances in thoracic oncology. Reversible EGFR tyrosine kinase inhibitors (TKIs), like gefitinib and erlotinib, are able to achieve dramatic responses in a subset of patients. However, most patients treated with TKIs eventually develop resistance against these drugs. Here we review the physiology and pathology of EGFR activation in NSCLC, the clinical experience with TKIs, the mechanisms of resistance against TKIs, and discuss various approaches to treat resistance against TKIs.

Activin tunes GABAergic neurotransmission and modulates anxiety-like behavior.

Activin, a member of the transforming growth factor-beta superfamily, affords neuroprotection in acute brain injury, but its physiological functions in normal adult brain are largely unknown. Using transgenic (tg) mice expressing a dominant-negative activin receptor mutant under the control of the CaMKIIalpha promoter in forebrain neurons, we identified activin as a key regulator of gamma-aminobutyric acid (GABA)ergic synapses and anxiety-like behavior. In the open field, wild-type (wt) and tg mice did not differ in spontaneous locomotion and exploration behavior. However, tg mice visited inner fields significantly more often than wt mice. In the light-dark exploration test, tg mice made more exits, spent significantly more time on a well-lit elevated bar and went farther away from the dark box as compared to wt mice. In addition, the anxiolytic effect of diazepam was abrogated in tg mice. Thus the disruption of activin receptor signaling produced a low-anxiety phenotype that failed to respond to benzodiazepines. In whole-cell recordings from hippocampal pyramidal cells, enhanced spontaneous GABA release, increased GABA tonus, reduced benzodiazepine sensitivity and augmented GABA(B) receptor function emerged as likely substrates of the low-anxiety phenotype. These data provide strong evidence that activin influences pre- and postsynaptic components of GABAergic synapses in a highly synergistic fashion. Given the crucial role of GABAergic neurotransmission in emotional states, anxiety and depression, dysfunctions of activin receptor signaling could be involved in affective disorders: and drugs affecting this pathway might show promise for psychopharmacological treatment.

Preemptive analgesia by lornoxicam--an NSAID--significantly inhibits perioperative platelet aggregation.

BACKGROUND AND OBJECTIVE: To investigate whether preemptive administered lornoxicam changes perioperative platelet function during thoracic surgery. METHODS: A total of 20 patients scheduled for elective thoracic surgery were randomly assigned to receive either lornoxicam (16 mg, i.v.; n = 10) or placebo (n = 10) preoperatively. All patients underwent treatment of solitary lung metastasis and denied any antiplatelet medication within the past 2 weeks. Blood samples were drawn via an arterial catheter directly into silicone-coated Vacutainer tubes containing 0.5 mL of 0.129 M buffered sodium citrate 3.8% before, 15 min, 4 h and 8 h after the study medication was administered. Platelet aggregation curves were obtained by whole blood electrical impedance aggregometry (Chrono Log). RESULTS: Platelet aggregation was significantly reduced 15 min, 4 h and 8 h after lornoxicam administration compared to placebo (P < 0.05) for collagen, adenosine diphosphate and arachidonic acid as trigger substances. Adenosine diphosphate-induced platelet aggregation decreased by 85% 15 min after lornoxicam administration, and remained impaired for 8 h. CONCLUSION: Platelet aggregation assays are impaired for at least 8 h after lornoxicam application. Therefore perioperative analgesia by use of lornoxicam should be carefully administered under consideration of subsequent platelet dysfunction.

DNA excision repair profiles of normal and leukemic human lymphocytes: functional analysis at the single-cell level.

Recent evidence has linked cellular DNA repair capacity to the chemosensitivity of cancer cells to alkylating agents. Using single-cell gel electrophoresis ("comet assay"), we have analyzed the induction and differential processing of DNA damage in human lymphocytes derived from healthy donors and from patients with chronic lymphatic leukemia (CLL) after exposure to N-ethyl-N-nitrosourea in vitro. The extent of comet formation in lymphocytes after N-ethyl-N-nitrosourea exposure appears to depend predominantly on the processing of DNA repair intermediates, because strand breaks in plasmid DNA were not induced by ethylation before the addition of nuclear proteins. Although the initial level of a specific alkylation product (O6-ethylguanine) in nuclear DNA was uniform, different dose-response curves were obtained for the comet size in individual cell samples immediately after exposure, with small intercellular variation. The individual kinetics of DNA repair varied significantly between specimens derived from both healthy individuals and CLL patients; for the DNA repair half-time (t1/2), large difference was found. Pretreatment of cells with methoxyamine as a DNA repair modifier blocking the base excision repair pathway revealed a quite similar extent of base excision repair-independent DNA incision in almost all normal lymphocyte samples. In contrast, this portion varied relatively and absolutely to a great extent among individual samples of CLL lymphocytes, suggesting a loss of stringent control of DNA repair processes in these cells. The comet assay can thus be used to gain information about interindividual variation in the efficiency of different DNA repair processes in small samples of normal cells and their malignant counterparts.

Capacity of individual chronic lymphatic leukemia lymphocytes and leukemic blast cells for repair of O6-ethylguanine in DNA: relation to chemosensitivity in vitro and treatment outcome.

The elimination kinetics of the alkylation product O6-ethylguanine (O6eGua) from nuclear DNA were determined in individual lymphocytes or blast cells isolated from 27 patients with chronic lymphatic leukemia (CLL) and 26 patients with de novo acute myeloid leukemia (AML). A monoclonal antibody-based immunocytological assay was used for quantification of O6eGua in DNA of individual cells after pulse exposure of cells to N-ethyl-N-nitrosourea (EtNU). In cell specimens from a given patient, no major subpopulations with significantly different capacities for repair of O6eGua were observed. The time required to remove 50% of induced O6eGua residues varied interindividually between 0.5 and 8.4 h in CLL lymphocytes and between 0.8 and 6.3 h in leukemic blast cells. An inverse relationship was found between the rate of removal of O6eGua from DNA and the chemosensitivity of cells to EtNU, 1,3-bis(2-chloroethyl)-1-nitrosourea or mafosfamide in vitro. High rates of O6eGua repair and pronounced resistance to mafosfamide, 1,3-bis(2-chloroethyl)-1-nitrosourea, and EtNU in vitro were found in samples from 8 CLL patients nonresponsive to chemotherapy with alkylating agents. In AML patients treated with anthracyclines and 1-beta-D-arabinofuranosylcytosine, no relation was found between DNA repair capacity and treatment outcome. However, increased P-glycoprotein expression was observed between specimens derived from AML patients who had failed to reach complete remission (n = 12) after chemotherapy versus responsive patients (n = 14). DNA repair rate was not related to chemosensitivity to Adriamycin and 1-beta-D-arabinofuranosylcytosine in vitro, nor were cellular glutathione content, glutathione S-transferases activity, or P-glycoprotein expression.

Evaluation of cyclosporine-sparing effects of polyunsaturated fatty acids in the treatment of canine atopic dermatitis.

A randomised, double-blinded, placebo-controlled multicentre trial was conducted in 36 dogs with atopic dermatitis to evaluate the cyclosporine-sparing effect of polyunsaturated fatty acids. Dogs were stable on their individual cyclosporine dosage and received either a mainly omega-3 fatty acid product with a minor omega-6 fatty acid fraction or placebo, orally for 12 weeks. Dogs were examined every 4 weeks and the Canine Atopic Dermatitis Extent and Severity Index (CADESI-03) was determined by a clinician. Pruritus, quality of life, global condition and coat quality were scored by the owner. If the dog's CADESI-03 and/or pruritus score improved by at least 25% compared with the previous visit, the cyclosporine dosage was decreased by approximately 25%. If the scores deteriorated by at least 25%, the cyclosporine dosage was increased by the same percentage. The median daily cyclosporine dosage/kg bodyweight decreased in the active group from 4.1 mg to 2.6 mg and in the placebo group from 3.5 mg to 3.3 mg over the study period. The difference between the two groups was significant (P = 0.009). The improvement in median pruritus score from inclusion to completion was significantly greater in the active group than in the placebo group (P = 0.04). There was no significant difference in CADESI-03 changes between groups (P = 0.38). The results of this study indicate a cyclosporine-sparing effect of a mainly omega-3 fatty acid supplement in dogs with atopic dermatitis.

Differences in genome-wide gene expression response in peripheral blood mononuclear cells between young and old men upon caloric restriction.

BACKGROUND: Caloric restriction (CR) is considered to increase lifespan and to prevent various age-related diseases in different nonhuman organisms. Only a limited number of CR studies have been performed on humans, and results put CR as a beneficial tool to decrease risk factors in several age-related diseases. The question remains at what age CR should be implemented to be most effective with respect to healthy aging. The aim of our study was to elucidate the role of age in the transcriptional response to a completely controlled 30 % CR diet on immune cells, as immune response is affected during aging. Ten healthy young men, aged 20-28, and nine healthy old men, aged 64-85, were subjected to a 2-week weight maintenance diet, followed by 3 weeks of 30 % CR. Before and after 30 % CR, the whole genome gene expression in peripheral blood mononuclear cells (PBMCs) was assessed. RESULTS: Expression of 554 genes showed a different response between young and old men upon CR. Gene set enrichment analysis revealed a downregulation of gene sets involved in the immune response in young but not in old men. At baseline, immune response-related genes were higher expressed in old compared to young men. Upstream regulator analyses revealed that most potential regulators were controlling the immune response. CONCLUSIONS: Based on the gene expression data, we theorise that a short period of CR is not effective in old men regarding immune-related pathways while it is effective in young men. TRIAL REGISTRATION: ClinicalTrials.gov, NCT00561145.

Gate-Controlled WSe2 Transistors Using a Buried Triple-Gate Structure.

In the present paper, we show tungsten diselenide (WSe2) devices that can be tuned to operate as n-type and p-type field-effect transistors (FETs) as well as band-to-band tunnel transistors on the same flake. Source, channel, and drain areas of the WSe2 flake are adjusted, using buried triple-gate substrates with three independently controllable gates. The device characteristics found in the tunnel transistor configuration are determined by the particular geometry of the buried triple-gate structure, consistent with a simple estimation of the expected off-state behavior.

Synthesis and secretion of the human vitamin B12-binding protein, transcobalamin II, by cultured skin fibroblasts and by bone marrow cells.

Human skin fibroblasts and bone marrow cells were tested for their ability to synthesize the cobalamin-binding protein transcobalamin II. Cobalamin binders secreted in the media of cultured fibroblasts and of dextran-sedimented bone marrow cells in liquid culture could be identified as transcobalamin II on the basis of immunological, electrophoretical and chromatographical identity with serum transcobalamin II. The net secretion of transcobalamin II increased linearly with time of culture, up to 30 days after confluence. The reversible inhibition of transcobalamin II secretion by cycloheximide demonstrated that human fibroblasts are capable of de novo transcobalamin II synthesis. Addition of cyanocobalamin to the fibroblast culture medium induced a reduction of transcobalamin II net secretion, most likely due to preferred uptake of transcobalamin II saturated with cobalamin, as opposed to unsaturated protein. Addition of lysozymal enzyme inhibitors, ammonium chloride and chloroquine, resulted in a markedly increased secretion of transcobalamin II. In the culture medium of fibroblasts, obtained from two transcobalamin II-deficient patients, functionally deficient transcobalamin II was demonstrated on the basis of strongly reduced secretion of immunoreactive transcobalamin II, and the absence of apotranscobalamin II. Individual phenotypes in the culture media of the fibroblasts and bone marrow cells were identical to the corresponding serum transcobalamin II types.

The branching angles in computer-generated optimized models of arterial trees.

The structure of a complex arterial tree model is generated on the computer using the newly developed method of "constrained constructive optimization." The model tree is grown step by step, at each stage of development fulfilling invariant boundary conditions for pressures and flows. The development of structure is governed by adopting minimum volume inside the vessels as target function. The resulting model tree is analyzed regarding the relations between branching angles and segment radii. Results show good agreement with morphometric measurements on corrosion casts of human coronary arteries reported in the literature.

DNA repair and cellular resistance to alkylating agents in chronic lymphocytic leukemia.

The time course of the formation and persistence of repair-induced DNA lesions such as single-strand breaks (SSBs) were determined in isolated lymphocytes derived from 32 patients with chronic lymphocytic leukemia (CLL) using the single-cell gel electrophoresis (SCGE, "comet") assay. After pulse-exposure to N-ethyl-N-nitrosourea (EtNU), the initial amount of SSBs (t0 SCGE values) and the time periods required to reduce DNA damage by 50% (t50% SCGE values) were determined in nuclear DNA of individual cells. The t0 SCGE and t50% SCGE values varied interindividually between CLL specimens by factors of 16.6 and 8.2, respectively. Regarding cell-to-cell variation, no major subpopulations with significantly different DNA repair capacities were observed in cell specimens from a given patient. In addition, a monoclonal antibody-based immunocytological assay was used to determine the elimination kinetics for the cytotoxic alkylation product O6-ethylguanine from nuclear DNA. A strong correlation was observed between the relative times for SSB repair and the elimination of O6-ethylguanine from nuclear DNA. Because SCGE and immunocytological assay measure different steps of DNA repair, this observation suggests coordinated regulation of the respective repair pathways. With regard to chemosensitivity profiles, a "fast" repair phenotype corresponded to enhanced in vitro resistance to EtNU, 1,3-bis(2-chloroethyl)-1-nitrosourea, or chlorambucil. Accelerated SSB repair and pronounced in vitro resistance to chlorambucil, 1,3-bis(2-chloroethyl)-1-nitrosourea, and EtNU were found in lymphocytes from CLL patients nonresponsive to chemotherapy with alkylating agents. Distinct DNA repair processes thus mediate resistance to alkylating agents in CLL lymphocytes.

Stem cell factor-induced downregulation of c-kit in human lung mast cells and HMC-1 mast cells.

Recent data suggest that local overexpression of the tissue-hormone c-kit ligand (stem cell factor [SCF]) is associated with accumulation of mast cells (MCs) and a decrease in expression of c-kit in the accumulated MCs [28]. In the present study, the effects of recombinant human (rh) SCF on expression of c-kit mRNA and c-kit protein in isolated human MCs and a human mast cell line, HMC-1, were analyzed. Incubation of isolated lung MC with rhSCF (100 ng/mL) for 120 minutes resulted in decreased expression of c-kit mRNA (optical density [OD], control: 100% vs. rhSCF: 37%). Almost identical results were obtained with HMC-1 cells (OD, control: 100% vs. rhSCF: 40 to 45%). As assessed by flow cytometry and monoclonal antibodies (mAbs) to c-kit, the SCF-induced decrease of c-kit mRNA in HMC-1 was associated with a substantial decrease in surface expression of c-kit (MFI, control: 100 +/- 21%, vs. MFI in cells incubated with rhSCF [100 ng/mL at 37 degrees C for 12 hours]: 8 +/- 2%, vs. MFI in cells incubated with rhSCF, 100 ng/mL, at 4 degrees C: 34 +/- 3%). The effects of rhSCF on c-kit expression in HMC-1 cells were dose- and time-dependent with maximum effects observed with 10-100 ng/mL of rhSCF after 4 to 12 hours. The SCF-dependent loss of c-kit was also accompanied by a decreased chemotactic response to rhSCF (control: 100%; rhSCF: 71 +/- 2%). This study shows that exposure of human lung MC and HMC-1 cells to recombinant SCF results in downregulation of c-kit mRNA and surface c-kit expression. These data may explain the partial loss of c-kit on MCs in areas of SCF overexpression.

[Pulmonary infection in neutropenia]. / Pulmonale Infektion bei Neutropenie - Fall 1/2015.

UNLABELLED: MEDICAL HISTORY AND CLINICAL COURSE: A 42-year-old patient with hairy cell leukemia had been treated for 3 years by a hematologist in private practice. Initially the patient received 1 course of cladribine upon which the disease went into complete remission. 6 weeks ago a relapse was diagnosed and combination therapy with cladibrin and rituximab was initiated. Now the patient presented to the emergency room with shortness of breath and pain when breathing. INVESTIGATIONS, TREATMENT AND COURSE: In the chest x-ray, patchy infiltrates and pleural effusions were found on both sides. The subsequently performed computed tomography showed bilateral compactions with an Halo suspicious for fungal infiltrates. Upon admission to the hospital, an empirical antibiotic therapy with clarithromycin and piperacillin/tazobactam was initiated, which was later escalated to meropenem and linezolid. Additionally, an antifungal therapy with voriconazole was started and later switched to liposomal amphotericin B. At his admission, a positive aspergillus antigen could be detected in the microbiological laboratory. Under antimycotic treatment the aspergillus antigen was repeatedly negative. The patient presented with pronounced cytopenias and after a switch of therapy to vemurafenib and filgrastim, the hematopoiesis could only be stimulated insufficiently. The patient was transferred to the intensive care unit three days after admission with severe respiratory failure. He died on day 8 after admission. AUTOPSY AND DIAGNOSIS: Diagnosis was consistent with relapse of hairy cell leukemia with positive BRAF mutation and a bone marrow infiltration > 80 %. Autopsy revealed a significant hepato-splenomegaly, a lack of erythro-, granulo- and thrombopoiesis. Clots interspersed with fungal hyphae were found in both lungs and an infarction of the spleen with evidence of fungal hyphae was detected. The cultural findings post mortem on yeast or mold were negative. CONCLUSION: Patients with refractory hairy cell leukemia and prolonged neutropenia are at increased risk for systemic fungal infections. Therefore, prohylactic antimycotic therapy should be considered early in this group of patients. The therapeutic approach of vemurafenib in treatment-refractory hairy cell leukemia is promising and offers an additional treatment option. In the present case, the patient could unfortunately not be stabilized due to the septic complications.

Thrombin augments vascular cell-dependent migration of human mast cells: role of MGF.

Recent data suggest that auricular thrombosis is associated with accumulation of mast cells (MC) in the upper endocardium (where usually no MC reside) and local expression of MGF (mast cell growth factor) (25). In this study, the role of vascular cells, thrombin-activation and MGF, in MC-migration was analyzed. For this purpose, cultured human auricular endocardial cells (HAUEC), umbilical vein endothelial cells (HUVEC) and uterine- (HUTMEC) and skin-derived (HSMEC) microvascular endothelial cells were exposed to thrombin or control medium, and the migration of primary tissue MC (lung, n = 6) and HMC-1 cells (human MC-line) against vascular cells (supernatants) measured. Supernatants (24 h) of unstimulated vascular cells (monolayers of endocardium or endothelium) as well as recombinant (rh) MGF induced a significant migratory response in HMC-1 (control: 3025 +/- 344 cells [100 +/- 11.4%] vs. MGF, 100 ng/ml: 8806 +/- 1019 [291 +/- 34%] vs. HAUEC: 9703 +/- 1506 [320.8 +/- 49.8%] vs. HUTMEC: 8950 +/- 1857 [295.9 +/- 61.4%] vs. HSMEC: 9965 +/- 2018 [329.4 +/- 66.7%] vs. HUVEC: 9487 +/- 1402 [313.6 +/- 46.4%], p < 0.05) as well as in primary lung MC. Thrombin-activation (5 U/ml, 12 h) of vascular cells led to an augmentation of the directed migration of MC as well as to a hirudin-sensitive increase in MGF synthesis and release. Moreover, a blocking anti-MGF antibody was found to inhibit MC-migration induced by unstimulated or thrombin-activated vascular cells. Together, these data show that endocardial and other vascular cells can induce migration of human MC. This MC-chemotactic signal of the vasculature is associated with expression and release of MGF, augmentable by thrombin, and may play a role in the pathophysiology of (auricular) thrombosis.

Prognostic significance of agar and liquid cultures in AML patients before treatment, early postinduction and in remission.

In the present study, the growth and differentiation capacity of myeloid leukemic cells in agar and liquid cultures have been investigated in relation to their prognostic significance for treatment outcome and early detection of relapse. Prior to induction therapy, leukemic cells failed to differentiate and the colony or cluster number did not correlate with response to treatment. Seventeen to 42 days after induction, patients with BM cells producing greater than 10 colonies or greater than 30 clusters resp. had a high likelihood of achieving a complete remission. Cells from refractory patients had a significantly impaired differentiation capacity. During remission, a colony number greater than 50 was significantly associated with a high probability to remain in further remission for greater than 3 months. An impaired differentiation was significantly associated with the likelihood of relapsing within 3 months. In the light of these results, agar and liquid cultures appear to be useful for monitoring the effect of induction chemotherapy and detecting patients likely to relapse.

Differential modulation of chemosensitivity to alkylating agents and platinum compounds by DNA repair modulators in human lung cancer cell lines.

PURPOSE: Modulation of DNA repair represents one strategy to overcome cellular drug resistance to alkylating agents and platinum compounds. The effects of different known DNA repair modulators such as O6-benzylguanine (6 microg/ml), fludarabine (25 ng/ml), aphidicolin (8.5 ng/ml), pentoxifylline (1.4 microg/ml) and methoxamine (12.4 microg/ml) on the cytotoxicity of mafosfamide, chlorambucil, 1,3-bis-(2-chloroethyl)-1-nitrosourea (BCNU), cisplatin and carboplatin were tested in human lung cancer cell lines. METHODS: Chemosensitivity of the human adenocarcinoma cell line MOR/P and the cisplatin-resistant subline MOR/CPR as well as the large-cell lung cancer cell line L23/P and its cisplatin-resistant counterpart L23/CPR were evaluated by the MTT colorimetric assay. RESULTS: O6-benzylguanine, an inhibitor of O6-alkylguanine-DNA alkyltransferase, significantly sensitised MOR/P and MOR/CPR cells to the cytotoxic effect of BCNU. Fludarabine, methoxamine and aphidicolin did not change the chemosensitivity of the parental and cisplatin-resistant cell lines to any cytotoxic drug tested. Interestingly, O6-benzylguanine enhanced the chemoresistance of parental and cisplatin-resistant cell lines to platinum compounds. Also, pentoxifylline increased resistance of the MOR cell lines to mafosfamide. CONCLUSIONS: Modulation of DNA repair elicits not only chemosensitisation but may also enhance cellular resistance to DNA-affine drugs.

Modulation of multidrug resistance by BIBW22BS in blasts of de novo or relapsed or persistent acute myeloid leukemia ex vivo.

The phenylpteridine derivative BIBW22BS (BIBW22) is a potent modulator of multidrug resistance (MDR). We investigated BIBW22 in comparison to dexniguldipine and verapamil as modifier of MDR in blasts of de novo, relapsed or persistent acute myeloid leukemia (AML) in vitro. All patients with relapsed or persistent AML had been pretreated with idarubicin and cytosine arabinoside. The degree of MDR was determined by efflux kinetics of rhodamine 123 (R123), daunorubicin, and idarubicin measured by flow cytometry (FACS). A total of 51 patients with AML, 25 de novo and 26 relapsed or persistent, were investigated. While only 6 out of 25 de novo AML blast populations showed moderate efflux of R123 and daunorubicin, 17 out of 26 blast populations of relapsed or persistent AML had an efflux between 20% and 44% within 15 min ex vivo. This efflux could be significantly inhibited by 1 microM BIBW22, 1 microM dexniguldipine, or 10 microM verapamil. For idarubicin we found an effusion of 40+/-9% within 15 min in all blast populations that could not be inhibited by the modulators. Clinically achievable drug concentrations causing only moderate side-effects are in the range of 0.5 microM dexniguldipine and 3 microM verapamil. Up to now, BIBW22 has not been investigated clinically. Thus the potential toxicity of concentrations of 0.5-1 microM BIBW22, sufficient for an optimal efflux inhibition ex vivo, is not known yet. We conclude from our ex vivo investigations in blast populations of de novo, relapsed or persistent AML that BIBW22 is a potent modulator of MDR.

Long-term results after repeated surgical removal of pulmonary metastases.

BACKGROUND: Although surgical resection is accepted widely as first-line therapy for pulmonary metastases, few data exist on the surgical treatment of recurrent pulmonary metastatic disease. In a retrospective study, we analyzed patients who were operated on repeatedly for recurrent metastatic disease of the lung with curative intent over a 20-year period. METHODS: From 1973 to 1993, 396 metastasectomies were performed in 330 patients. The study population included patients with any histologic tumor type who had undergone at least two (range, 2 to 4) complete surgical procedures because of recurrent metastatic disease. Surgical and functional resectability of the recurrent lung metastases and control of the primary lesion served as objective criteria for reoperation. A subgroup of 35 patients that included patients with histologic findings such as epithelial cancer and osteosarcoma then was analyzed retrospectively to calculate prognosis and define selection criteria for repeated pulmonary metastasectomy. RESULTS: The 5- and 10-year survival rates after the first metastasectomy were 48% and 28%, respectively. The overall median survival was 60 months. A mean disease-free interval (calculated for all intervals, with a minimum of two) of greater than 1 year was significantly associated with a survival advantage beyond the last operation. Univariate analysis failed to show size, number, increase or decrease in number or size, or distribution of metastases as factors related significantly to survival. CONCLUSIONS: Although patients with different histologic tumor types were included, the study population appeared to be homogeneous in terms of survival benefit and prognostic factors, and it probably represented the selection of biologically favorable tumors in which histology, size, number, and laterality are of minor importance. We conclude that patients who are persistently free of disease at the primary location but who have recurrent, resectable metastatic disease of the lung are likely to benefit from operation a second, third, or even fourth time.