Axon guidance receptors: Endocytosis, trafficking and downstream signaling from endosomes

During the development of the nervous system, axons extend through complex environments. Growth cones at the axon tip allow axons to find and innervate their appropriate targets and form functional synapses. Axon pathfinding requires axons to respond to guidance signals and these cues need to be detected by specialized receptors followed by intracellular signal integration and translation. Several downstream signaling pathways have been identified for axon guidance receptors and it has become evident that these pathways are often initiated from intracellular vesicles called endosomes. Endosomes allow receptors to traffic intracellularly, re-locating receptors from one cellular region to another. The localization of axon guidance receptors to endosomal compartments is crucial for their function, signaling output and expression levels. For example, active receptors within endosomes can recruit downstream proteins to the endosomal membrane and facilitate signaling. Also, endosomal trafficking can re-locate receptors back to the plasma membrane to allow re-activation or mediate downregulation of receptor signaling via degradation. Accumulating evidence suggests that axon guidance receptors do not follow a pre-set default trafficking route but may change their localization within endosomes. This re-routing appears to be spatially and temporally regulated, either by expression of adaptor proteins or co-receptors. These findings shed light on how signaling in axon guidance is regulated and diversified - a mechanism which explains how a limited set of guidance cues can help to establish billions of neuronal connections. In this review, we summarize and discuss our current knowledge of axon guidance receptor trafficking and provide directions for future research.

Randomized phase II trial of first-line treatment with sorafenib versus interferon in patients with advanced renal cell carcinoma: Final results

5025

Background: This trial investigated the efficacy and safety of sorafenib (SOR) vs interferon (IFN) in treatment-naïve patients with clear-cell renal cell carcinoma (RCC). Methods: Previously untreated patients with advanced RCC were randomized to continuous oral SOR 400 mg bid or IFN 9 million units tiw (part 1), with an option of dose escalation to SOR 600 mg bid or crossover from IFN to SOR 400 mg bid upon disease progression (part 2). The primary endpoint was progression-free survival (PFS). Results: Baseline characteristics (ITT, n=189) were similar in SOR (n=97) and IFN (n=92) groups. In the IFN arm, 90/92 patients received treatment; 56 had disease progression, of which 50 crossed to SOR. All 97 patients in the SOR arm received SOR 400 mg bid; 65 had disease progression, of which 44 were dose escalated to 600 mg bid. In part 1, 5% vs 9% patients had complete/partial response, disease control rate (complete/partial response + stable disease) was 79% vs 64%, and median PFS was 5.7 months (CI: 5.0–7.4 months) vs 5.6 months (CI: 3.7–7.4 months) for SOR vs IFN, respectively. Progression-free rates for SOR vs IFN were 90.0% vs 70.4%, 45.9% vs 46.5%, and 11.5% vs 30.4% at 3, 6, and 12 months, respectively. A total of 11% vs 15% of patients receiving SOR or IFN, respectively, discontinued due to adverse events. Overall, the incidence of adverse events was similar between both treatment arms, although skin toxicity (rash and hand-foot skin reaction) and diarrhea occurred more frequently in the SOR group, and flu-like syndrome occurred more frequently in the IFN group. In part 2, median PFS was 5.3 months (CI: 3.6–6.1 months) in patients (n=50) who crossed from IFN to SOR. The median PFS for patients (n=44) with dose escalation to 600 mg bid was 3.6 months (CI: 1.9–5.3 months). The 600 mg bid dose was well tolerated. Conclusions: Although the primary endpoint (PFS) was not reached, SOR showed activity in first-line treatment of RCC based on disease control rate. PFS benefit was observed in patients who crossed to SOR 400 mg bid after progression on IFN. Patients who were dose escalated to 600 mg bid after progression had disease stabilization for a further 3.6 months. Further analyses of possible benefit from SOR dose escalation are required in a larger number of patients.

[Table: see text]

Pharmacokinetic results of a phase I trial of sorafenib (S) in combination with dacarbazine (DTIC) in patients with advanced metastatic melanoma or other solid tumors

2563

Background: Sorafenib (S) is a multikinase inhibitor that prevents tumor cell proliferation and angiogenesis via receptor tyrosine kinases, VEGFR-1, -2, -3 and PDGFR-a and -β, and the Raf/MEK/ERK pathway at the level of Raf kinase. Single-agent studies show S is well tolerated with manageable and reversible side effects, most commonly, diarrhea, rash, fatigue, and hand-foot skin (HFS) reaction. This phase I study assessed the safety and pharmacokinetics (PK) of the combination of S and DTIC. Methods: 23 patients (pts) received a fixed dose of DTIC (1,000 mg/m2 given every 3 wks) starting on Day 1 of cycle 1 (C1). S (400 mg bid) was given on days 2–21 in C1 and continuously thereafter. PK profiles of DTIC and 5-aminoimidazole-4-carboxamide (AIC; an inactive D metabolite that is formed in an equal proportion to the active moiety, diazomethane, that cannot be analytically measured) were obtained from day 1 of both C1 and C2 and PK profiles of S from Day 1 of C2. Results: 23 pts (M:F, 11:12; mean age 57±9 yrs) were treated with S and DTIC. Of these pts, 15 were valid for PK analysis. Following simultaneous administration of S, mean AUC and Cmax of DTIC were moderately reduced by 23% and 16%, while mean AUC and Cmax of AIC were increased by 41% and 45%, respectively. Mean AUC (0–12)ss and Cmax,ss of S were 28.3 mg*h/L (84%) and 3.67 mg/L (77%), respectively, upon concomitant dosing of S and DTIC. These sorafenib exposures are within the range of exposures observed in phase I studies. Six pts had an increase of either Cmax or AUC of AIC of at least 70%, and in 4 of the 6 pts, this increase was correlated with grade 4 thrombocytopenia. Conclusions: The combination of S and DTIC resulted in moderate decreases of DTIC exposure; however, more pronounced increases in AIC exposure were observed. In patients with a distinct increase (=70%) in AIC, a correlation between exposure and toxicity cannot be excluded, however, all toxicities were manageable.

No significant financial relationships to disclose.

Phase II trial of sorafenib combined with dacarbazine in metastatic melanoma patients

8012

Background: Sorafenib inhibits tumor cell proliferation and angiogenesis through blockade of multiple kinases including Raf, VEGFR-2/-3, and PDGFR-β. In Phase I/II trials, sorafenib was generally well tolerated as a monotherapy or in combination with other agents. A Phase I study in combination with dacarbazine (DTIC) showed encouraging activity, which warranted this Phase II study. Methods: This multi-center, open-label, two-stage (30 patients in Stage 1; 52 in Stage 2), uncontrolled Phase II trial was performed to evaluate the primary endpoints of efficacy (according to RECIST) and tolerability of sorafenib in combination with DTIC in patients with advanced metastatic melanoma. Eligibility criteria included ECOG 0 or 1, life expectancy ≥12 weeks, adequate bone marrow, liver, and renal function. Oral sorafenib 400 mg twice daily (bid) was administered with repeated 3-week cycles of DTIC 1000 mg/m2. Results: At this interim end of Stage 1 analysis, 30 patients with metastatic melanoma had been treated (median age 61 years [range 30–78]; 73.3% male; 96.7% white). Five (16.7%) patients had PR as best response (two confirmed, three currently unconfirmed), 13 (43.3%) had SD, 10 (33.3%) had PD, and two (6.7%) were unevaluable for tumor response. The patients with confirmed PR continue on study drug at 6.4 months. Median progression-free survival for all patients was 3.6 months (range 0.9–6.1 months). The most frequently reported drug-related adverse events (AEs) were dermatologic (rash/desquamation [43%], hand-foot skin reaction [HFS, 33%]); gastrointestinal (constipation [47%], nausea [37%], diarrhea [27%]); constitutional (fatigue [43%]); and blood/bone marrow (neutrophils [40%], platelets [30%]). The most common grade 3/4 drug-related AEs were blood/bone marrow (neutrophils [23%], platelets [17%]), and fatigue (7%), while HFS and hypertension were observed in <5%. Conclusions: Continuous sorafenib 400 mg bid is generally well tolerated and shows promising preliminary anti-tumor activity in combination with DTIC. No toxicities were observed above those expected from either agent alone. Updated results will be presented, including the decision whether to proceed to Stage 2 of the study.

[Table: see text]

Phase II study of MTX-HSA in combination with Cisplatin as first line treatment in patients with advanced or metastatic transitional cell carcinoma

PURPOSE

To assess the efficacy, tolerability and safety of MTX-HSA (methotrexate (MTX) covalently linked to human serum albumin (HSA)) combined with cisplatin as first line therapy for advanced bladder cancer.

METHODS

Patients (pat) were treated with a loading dose of 110 mg/m(2) of MTX-HSA followed by a weekly dose of 40 mg/m(2) starting on day 8. Cisplatin was given on day 2 of each 28 day cycle at a dose of 75 mg/m(2).

RESULTS

Tumor response evaluation was possible in 7 patients. Complete response (CR) and partial response (PR) was observed in 1 patient each (overall response rate: 29%). Key toxicities included CTC Grade (G) 3/4 stomatitis in 6 patients, vomiting G3 in 1 patient, fatigue G3 in 1 patient and thrombocytopenia G3 in 3 patients.

CONCLUSION

The combination of MTX-HSA with cisplatin is feasible and shows antitumor activity against urothelial carcinomas combined with an acceptable toxicity profile.

The alpha-synuclein gene in multiple system atrophy

BACKGROUND

The formation of alpha-synuclein aggregates may be a critical event in the pathogenesis of multiple system atrophy (MSA). However, the role of this gene in the aetiology of MSA is unknown and untested.

METHOD

The linkage disequilibrium (LD) structure of the alpha-synuclein gene was established and LD patterns were used to identify a set of tagging single nucleotide polymorphisms (SNPs) that represent 95% of the haplotype diversity across the entire gene. The effect of polymorphisms on the pathological expression of MSA in pathologically confirmed cases was also evaluated.

RESULTS AND CONCLUSION

In 253 Gilman probable or definite MSA patients, 457 possible, probable, and definite MSA cases and 1472 controls, a frequency difference for the individual tagging SNPs or tag-defined haplotypes was not detected. No effect was observed of polymorphisms on the pathological expression of MSA in pathologically confirmed cases.

The fragile X tremor ataxia syndrome in the differential diagnosis of multiple system atrophy: data from the EMSA Study Group

The recent identification of fragile X-associated tremor ataxia syndrome (FXTAS) associated with premutations in the FMR1 gene and the possibility of clinical overlap with multiple system atrophy (MSA) has raised important questions, such as whether genetic testing for FXTAS should be performed routinely in MSA and whether positive cases might affect the specificity of current MSA diagnostic criteria. We genotyped 507 patients with clinically diagnosed or pathologically proven MSA for FMR1 repeat length. Among the 426 clinically diagnosed cases, we identified four patients carrying FMR1 premutations (0.94%). Within the subgroup of patients with probable MSA-C, three of 76 patients (3.95%) carried premutations. We identified no premutation carriers among 81 patients with pathologically proven MSA and only one carrier among 622 controls (0.16%). Our results suggest that, with proper application of current diagnostic criteria, FXTAS is very unlikely to be confused with MSA. However, slowly progressive disease or predominant tremor are useful red flags and should prompt the consideration of FXTAS. On the basis of our data, the EMSA Study Group does not recommend routine FMR1 genotyping in typical MSA patients.

MRI-based volumetric differentiation of sporadic cerebellar ataxia

The term idiopathic cerebellar ataxia (IDCA) designates a variety of cerebellar syndromes that may present with a purely cerebellar syndrome (IDCA-C) or with additional extracerebellar features (IDCA-P). Multiple system atrophy is also a sporadic neurodegenerative disorder of unknown origin that may cause prominent cerebellar symptoms (MSA-C). The final neuropathological answer to the question whether IDCA-P and MSA-C represent different varieties of one disease or two distinct entities is still lacking. Three-dimensional MRI-based volumetry allows morphological investigations intra vitam. Volumetric analysis of cerebellum, brainstem and basal ganglia was therefore performed in 46 patients with sporadic cerebellar ataxia and 16 age-matched healthy controls. Patients with dementia were excluded from the study since cognitive impairment is an exclusion criterion for the diagnosis of MSA. Cerebellar patients were clinically divided into two groups: 33 patients with multiple system atrophy with prominent cerebellar symptoms (MSA-C) and 13 patients with extracerebellar features not corresponding to MSA-C (IDCA-P). There was evidence for substantial cerebellar atrophy in both cerebellar groups while additional brainstem atrophy was significantly more pronounced in MSA-C patients. Absolute caudate and putamen atrophy was found to be restricted to single MSA-C individuals while group comparisons of mean volumes did not yield significant differences from controls. Based on the volumetric data, diagnosis could be correctly predicted in 94% of control, 82% of MSA-C and 100% of IDCA-P individuals. The finding of specific imaging characteristics strengthens (i) the value of MRI volumetry in separating MSA-C from other types of sporadic cerebellar ataxia, and (ii) the hypothesis of two independent neurodegenerative disorders in MSA-C and IDCA-P.

Phase I clinical and pharmacokinetic trial of the podophyllotoxin derivative NK611 administered as intravenous short infusion

BACKGROUND

NK611 is a novel podophyllotoxin derivative. Compared with etoposide, NK611 carries a dimethylamino group at the D-glucose moiety. The antitumor activity of NK611 showed to be equal or superior to etoposide in a variety of in vitro and in vivo tumor models. The aim of our present study was to determine the maximum tolerated dose and the dose-limiting toxicities of NK611 administered as intravenous infusion over 30 min every 28 days.

PATIENTS AND METHODS

45 patients (7 female, 38 male; median age 54 [range 37-73]) were enrolled. In a first stage, NK611 was administered without hematopoietic growth factor support; in a second stage, G-CSF was used for further dose escalation. Toxicities were assessed using WHO-criteria.

RESULTS

Initially, the dose was escalated from 60 mg/m2 to 120 mg/m2. In a second patient cohort, doses were further escalated with G-CSF support with doses ranging from 140 mg/m2 to 250 mg/m2. Dose-limiting toxicities were granulocytopenia and thrombocytopenia. Non-hematologic toxicities consisted of alopecia, mild nausea, and infection. Four partial responses were observed: two at 200 mg/m2 (pleural mesothelioma, response duration 7 months, and non-small cell lung cancer, response duration 13 months), and two at 250 mg/m2 (hepatocellular carcinoma, response duration 7 months, and non-small cell lung cancer, response duration 2 months). Pharmacokinetic analyses were performed in all patients. Using an open 3-compartment model, the terminal half-life (t1/2gamma) was 14.7 +/- 3.7 h. The AUC at 250 mg/m2 was determined to be 330 +/- 147 microg/mlh, the plasma clearance of NK611 was 16.2 +/- 8.2 ml/min x m2 and the V(ss) was 16.8 +/- 3.3 l/m2. Protein binding of NK611 was 98.7%.

CONCLUSION

the recommended dose for clinical Phase II studies is 120 mg/m2 without G-CSF support and 200 mg/m2 with G-CSF support.

P300 event-related potentials in stutterers and nonstutterers

This study investigated possible differences between adult stutterers and nonstutterers in the P300 event-related potential. Responses to tonal stimuli were recorded from electrodes placed over the left (C3) and righ (C4) hemispheres. The two groups exhibited different patterns of interhemispheric activity. Although all 8 participants in the fluent group exhibited P300s that were higher in amplitude over the right hemisphere, 5 of the 8 disfluent participants had higher amplitude activity over the left hemisphere. These results provide evidence that stutterers and nonstutterers may exhibit differences between hemispheres in the processing of some types of nonlinguistic (tonal) stimuli.

Noise level analysis of commercially available toys

There have been several isolated reports of hearing loss due to noise levels from toys. Guidelines for noise production by toys is regulated by the Voluntary Product Standards PS 72-76: Toy Safety Act of 1969. To determine the current risk of noise induced hearing loss from toys currently on the market, 25 toys were purchased at a national toy store chain and sound levels were measured at distances approximating ear level (2.5 cm) and a child's arm length (25 cm) from the surface of the toy. Testing revealed peak sound levels ranging from 81 to 126 dBA at 2.5 cm and 80 to 115 dBA at 25 cm from the surface of the toy.

Pharmacokinetics and pharmacodynamics of the new podophyllotoxin derivative NK 611. A study by the AIO groups PHASE-I and APOH

NK 611 is a new podophyllotoxin derivative in which a dimethyl amino group replaces a hydroxyl group at the sugar moiety of etoposide. This results in profound physico-chemical differences: NK 611 is much less hydrophobic than etoposide. Preclinical studies have shown that NK 611 is advantageous in terms of bioavailability and of the potency of its anticancer activity. A clinical phase I study was performed in cancer patients within the framework of the AIO. Additionally, its pharmacokinetics and pharmacodynamics were investigated. NK 611 was given to 26 patients at doses ranging from 60 to 140 mg/m2 [maximum tolerated dose (MTD) 120 mg/m2] in a 30-min infusion. Plasma and urine samples were collected from 25 patients and analyzed using a validated high-performance liquid chromatography (HPLC) assay procedure. The concentration versus time curve of total NK 611 in plasma samples was best described by a three-compartment model. The overall median pharmacokinetic values were as follows (ranges are given in parentheses): mean residence time (MRT) 16.5 (5.4-42.3)h, terminal half-life 14.0 (8.2-30.5)h, volume of distribution at steady state (V(ss)) 11.4 (7.9-18.1) l/m2 and plasma clearance (Cl(p)) 15.1 (3.6-36.4) ml min-1 m-2. The total systemic drug exposure, represented by the area under the curve (AUC), varied between 53.4 and 532.0 micrograms ml-1 h. The mean AUC (+/- SD) increased with the dose from 78.7 +/- 3.7 micrograms ml-1 h at 60 mg/m2 up to 202.8 +/- 157.2 micrograms ml-1 h at 120 mg/m2. The mean urinary excretion (UE) fraction of unchanged drug at 48 h after the end of the infusion varied between 3.0% and 25.8% of the total dose delivered. Analysis of ultrafiltrate samples showed a protein binding of approx.. 99%. The percentage reduction in white blood cells (WBC) and neutrophils (ANC) correlated with the dose, AUC, and AUC(free). The best relationship between the percentage of reduction in ANC and a pharmacokinetic parameter (AUC) took a nonlinear Hill-type form. The laboratory parameter for kidney or liver function did not correlate with the AUC. The variation of pharmacokinetic parameters within each dose level was profound. The reason for this pharmacological behavior remains unclear and should be investigated in further studies.

A trial of lobaplatin (D-19466) in platinum-resistant ovarian cancer

Long-term survival in epithelial ovarian cancer remains problematic despite multimodality therapy. A fundamental difficulty is the development of tumor resistance to platinum compounds. Analogs have been developed that demonstrate activity in platinum-resistant cell lines both in vitro and in vivo. Lobaplatin (D-19466), a third-generation compound, demonstrates significant activity in carboplatin and cisplatin-resistant cell lines. Lobaplatin was given to 17 assessable patients with platinum-refractory ovarian cancer. The drug was initially administered at a dose of 50 mg/m2 but was later reduced to 40 mg/m2 because of excessive thrombocytopenia. Nine patients required red cell transfusions during therapy. Cycles were repeated every 21-35 days (median cycle length 28 days). No objective responses were observed. Lobaplatin has no activity in platinum-resistant epithelial ovarian cancer.

Intravesical idarubicin--a phase-I study

In the scope of a pharmacokinetic and dose-finding study 33 patients received instillations of idarubicin in 11 different doses 1 h before scheduled transurethral resection of bladder cancer. The dose was increased continuously from 5 to 30 mg and the concentration from 0.25-1.5 mg/ml. Idarubicin uptake into tissue was measured along with the serum level. The results showed a clear correlation of the tissue levels with dose and concentration. A significantly higher concentration of idarubicin was measured in the tumor in comparison with the mucosa. Absorption into the muscle was minimal and serum levels were low. Systemic toxicity was not observed, but there were signs of local toxicity in 50% of the subjects. Cytotoxic concentrations in the mucosa were reached at doses of over 15 mg and concentrations of over 0.5 mg/ml. A phase-II study is in preparation.

Tissue disposition and plasma concentrations of idarubicin after intravesical therapy in patients with bladder tumors

We studied single doses of intravesical idarubicin (IDA) given as 1-h instillations to 33 patients with bladder tumors. The dose was escalated from 5 to 30 mg and the concentration, from 0.25 to 1.5 mg/ml for evaluation of the importance of both the total amount of drug and the drug concentration on the levels of IDA found in different tissues (tumor, mucosa and muscle). Additionally, plasma uptake over 24 h was studied. The results demonstrated that (1) the levels of IDA in extracts of bladder tumors were significantly higher than those in normal bladder tissue, (2) the incorporation of IDA into tumors depended on the total amount of drug instilled and on the concentration of drug in the instillation fluid, (3) cytotoxic concentrations of IDA were noted in all tumors when the total amount of drug instilled was greater than 15 mg and the drug concentration in the instillation fluid was greater than 0.33 mg/ml, and (4) plasma levels of IDA were negligible.

Pharmacokinetics and metabolism of iodo-doxorubicin and doxorubicin in humans

The pharmacokinetics of doxorubicin (DOX), iodo-doxorubicin (I-DOX) and their metabolites in plasma has been examined in five patients each receiving 50 mg/m2 of both anthracyclines as a bolus injection. Terminal half-life, mean residence time (MRT), peak plasma concentration Cmax, and area under the curve (AUC) appeared smaller for I-DOX, whereas its plasma clearance (CLP) and volume of distribution at steady state (Vss) were larger than for DOX. The major metabolite of I-DOX was iodo-doxorubicinol (I-AOL) followed by doxorubicinol aglycone (AOLON). The AUC of I-AOL was 6-times larger than that of its counterpart AOL, which is the major metabolite of DOX. AOLON generated after I-DOX administration is a further important metabolite, as its AUC was 10-times larger than that of AOLON generated from DOX. The other aglycones, such as doxorubicin aglycone (AON) and the 7-deoxy-aglycones were only minor metabolites after either I-DOX or DOX injection. The ratio AUCI-AOL/AOL/AUCI-DOX/DOX was 27 in the case of I-DOX and 0.4 after DOX. The terminal half-lives of the cytostatic metabolites I-AOL and AOL were similar, although a longer MRT for AOL was calculated. Both metabolites had much longer MRTs than their parent drugs. The MRTs of the aglycones AOLON and AON were greater than those of the 7-deoxy-aglycones after both I-DOX and DOX. Approximately 6% DOX and less than 1% I-DOX were excreted by the kidneys during the initial 48 h. About 5% of I-DOX was excreted via the kidneys as I-AOL. Aglycones were not detected in significant amounts.(ABSTRACT TRUNCATED AT 250 WORDS)

[Iodo-doxorubicin, a new anthracycline derivative. Current state of progress]

Iodo-doxorubicin belongs to the group of doxorubicin analogs with modifications at the 4'-position of the daunosamine sugar moiety. Epirubicin is the archetype of the analogs created by configurational changes at the sugar. In case of EPI, the hydroxy group at the 4'-position is equatorial instead axial. In case of I-DOX, the hydroxy group has been replaced by an iodine-atom. This exchange has a great influence on the basicity of the amino group at the 3'-position. The physico-chemical properties of I-DOX are markedly different from those of DOX and EPI. I-DOX is unprotonated at physiological pH and much more lipophilic than DOX. The preclinical screening showed greater potency of I-DOX in different tumor cell systems. Cardiotoxicity and tissue toxicity after extravasation were significantly reduced in case of I-DOX. The substance was evaluated within three phase-I-studies in Europe during 1988 to 1990. The most prominent toxicity observed was myelotoxicity. This type of toxicity was dose-dependent and reversible. Alopecia, stomatitis/mucositis were not seen at all. There was only minor nausea without vomiting. The measured thyroid parameters were not affected by administration of an iodine-containing drug, but long-term effects cannot be ruled out. No acute cardiotoxicity was observed. The pharmacokinetics and metabolism of I-DOX differ from those of DOX and EPI. The terminal half-life of I-DOX is shorter, the plasma clearance higher than of DOX. One major difference is the formation of iodo-doxorubicinol, which is much larger in case of I-DOX compared to DOX and EPI. This cytostatic metabolite has a long terminal half-life.

High dose epirubicin in refractory or relapsed non-seminomatous testicular cancer: a phase II study

Sixteen patients with metastatic nonseminomatous testicular cancer refractory to cisplatinum combination chemotherapy, were treated with epirubicin 100-120 mg/m2 q d 22. One partial remission lasting 6 months was achieved. Two additional patients had stabilisation of disease for 3 and 4 months. Median time to progression was 43 days. Myelosuppression was dose-limiting, with a WBC nadir of 1900/microliters. 4/30 cycles (13%) were associated with granulocytopenic fever. One patient developed a decline in cardiac ejection fraction without clinical signs of congestive heart failure. Epirubicin in this dosage and schedule has no major therapeutic activity in heavily pretreated non-seminomatous testicular cancer.

Toxicity, pharmacokinetics and metabolism of iododoxorubicin in cancer patients

25 patients, mostly pretreated, received 55 courses of iododoxorubicin as a single intravenous bolus every 2 weeks. The starting dose was 2 mg/m2 with seven steps to reach the dose-limiting toxicity level. 3 patients treated with 90 mg/m2 had WHO grade 4 myelotoxicity; 2 of these patients had not had cytostatic chemotherapy. 3 of 7 patients treated with 75 mg/m2 had grade 3-4 myelotoxicity; 4 had grade 1-2. Non-haematological toxicities were minor. Acute cardiotoxicity and objective tumour responses were not observed. Plasma and urine levels of iododoxorubicin and five metabolites were assayed in 16 patients. Metabolism to iododoxorubicinol was rapid and plasma clearance was dose-dependent and rapid. Plasma levels and the area under the curve for iododoxorubicin increased with dose. The mean residence time was 3.9 h in patients without liver metastasis and 10.4 h in patients with liver metastasis. Renal excretion was minor. The maximally tolerated dose was 90 mg/m2.

Association of human hepatocellular membrane fusions with non-A, non-B hepatitis

Liver biopsies from patients with alcoholic hepatitis, chemical hepatitis, or viral hepatitis types A, B, or non-A, non-B were examined by electron microscopy. Circular, fused, cytoplasmic membranes were observed in hepatocytes of 17% of patients with hepatitis type B and 92% of patients with hepatitis type non-A, non-B. The membrane alterations were not observed in hepatocytes of patients with the other types of hepatitis. The greater frequency of altered cytoplasmic membranes in hepatocytes of patients with non-A, non-B hepatitis was shown to be statistically significant (p less than 0.05) when compared to that in patients with viral hepatitis type B.

[Prevention of recurrence in non-invasive bladder carcinoma. Experiences with 400 patients]

We report the results of 2 randomized cooperative studies. The aim of the first study was to find the optimal instillation interval for recurrence prophylactic treatment of superficial bladder tumors using Adriamycin. For this purpose the patients were randomized into 3 groups, with different instillation intervals of 1, 2 and 4 weeks. All patients had 12 instillations with 50 mg Adriamycin in 30 ml saline. Summarizing the results of the 3 groups, it was possible to reduce the number of recurrences to 36% in the 1st year after TUR and 46% after 2 years. Three years after TUR 52% of the patients had a recurrence. Differences between the groups existed in the percentage of recurrences after completion of the instillation therapy and furthermore in the incidence of chemocystitis. Admitted to this first study were 197 patients from July 1979 to December 1980. We started a second study in January 1981, in which we combined the first tested instillation intervals. All patients had now 3 instillations at 1 week intervals followed by 6 instillations at 2 weeks intervals thereafter they had 8 instillations, at 4 weeks intervals. With this combination the number of recurrences could be reduced even further. One year after TUR recurrence was found in 11.4% of the patients and 2 years after TUR in 21.9%. In a median follow-up time of 17 months we found 24% recurrences. Admitted to the second study were 214 patients from January 1981 to May 1983.

[Treatment of metastasizing prostatic carcinoma with DMF. Presentation of a prospective study]

Logothetis and von Eschenbach first 1981 reported encouraging preliminary results of the DMF regimen (Doxorubicine = Adriamycin, Mitomycin, 5 Fluorouracil) in hormone refractory adenocarcinoma of the prostate. 60% out of 62 patients had an objective remission over a mean period of 27 weeks. At the beginning of this year together with 5 other hospitals we started our study based on the results of Logothetis. In difference to his study all of our patients had prior therapy with Estracyt and patients with extrapelvic radiation were excluded. It is too early to present our results but we believe that this regimen is an advancement in the therapy of terminal prostatic carcinoma.