Three-year follow-up analysis of the short-stitch versus long-stitch technique for elective midline abdominal closure randomized-controlled (ESTOIH) trial.

BACKGROUND: Clinical trials have shown reduced incisional hernia rates 1 year after elective median laparotomy closure using a short-stitch technique. With hernia development continuing beyond the first postoperative year, we aimed to compare incisional hernias 3 years after midline closure using short or long stitches in patients from the ESTOIH trial. METHODS: The ESTOIH trial was a prospective, multicenter, parallel-group, double-blind, randomized-controlled study of primary elective midline closure. Patients were randomized to fascia closure using a short- or long-stitch technique with a poly-4-hydroxybutyrate-based suture. A predefined 3-year follow-up analysis was performed with the radiological imaging-verified incisional hernia rate as the primary endpoint. RESULTS: The 3-year intention-to-treat follow-up cohort consisted of 414 patients (210 short-stitch and 204 long-stitch technique) for analysis. Compared with 1 year postoperatively, incisional hernias increased from 4.83% (20/414 patients) to 9.02% (36/399 patients, p = 0.0183). The difference between the treatment groups at 3 years (short vs. long stitches, 15/198 patients (7.58%) vs. 21/201 (10.45%)) was not significant (OR, 1.4233; 95% CI [0.7112-2.8485]; p = 0.31). CONCLUSION: Hernia rates increased significantly between one and 3 years postoperatively. The short-stitch technique using a poly-4-hydroxybutyrate-based suture is safe in the long term, while no significant advantage was found at 3 years postoperatively compared with the standard long-stitch technique. TRIAL REGISTRY: NCT01965249, registered on 18 October 2013.

Effects of the short-stitch technique for midline abdominal closure: short-term results from the randomised-controlled ESTOIH trial.

PURPOSE: The short-stitch technique for midline laparotomy closure has been shown to reduce hernia rates, but long stitches remain the standard of care and the effect of the short-stitch technique on short-term results is not well known. The aim of this study was to compare the two techniques, using an ultra-long-term absorbable elastic suture material. METHODS: Following elective midline laparotomy, 425 patients in 9 centres were randomised to receive wound closure using the short-stitch (USP 2-0 single thread, n = 215) or long-stitch (USP 1 double loop, n = 210) technique with a poly-4-hydroxybutyrate-based suture material (Monomax®). Here, we report short-term surgical outcomes. RESULTS: At 30 (+10) days postoperatively, 3 (1.40%) of 215 patients in the short-stitch group and 10 (4.76%) of 210 patients in the long-stitch group had developed burst abdomen [OR 0.2830 (0.0768-1.0433), p = 0.0513]. Ruptured suture, seroma and hematoma and other wound healing disorders occurred in small numbers without differences between groups. In a planned Cox proportional hazard model for burst abdomen, the short-stitch group had a significantly lower risk [HR 0.1783 (0.0379-0.6617), p = 0.0115]. CONCLUSIONS: Although this trial revealed no significant difference in short-term results between the short-stitch and long-stitch techniques for closure of midline laparotomy, a trend towards a lower rate of burst abdomen in the short-stitch group suggests a possible advantage of the short-stitch technique. TRIAL REGISTRY: NCT01965249, registered October 18, 2013.

Remote entanglement between a single atom and a Bose-Einstein condensate.

Entanglement between stationary systems at remote locations is a key resource for quantum networks. We report on the experimental generation of remote entanglement between a single atom inside an optical cavity and a Bose-Einstein condensate (BEC). To produce this, a single photon is created in the atom-cavity system, thereby generating atom-photon entanglement. The photon is transported to the BEC and converted into a collective excitation in the BEC, thus establishing matter-matter entanglement. After a variable delay, this entanglement is converted into photon-photon entanglement. The matter-matter entanglement lifetime of 100 µs exceeds the photon duration by 2 orders of magnitude. The total fidelity of all concatenated operations is 95%. This hybrid system opens up promising perspectives in the field of quantum information.

Isolation of primary human B lymphocytes from tonsils compared to blood as alternative source for ex vivo application.

B lymphocytes ('B cells') are components of the human immune system with obvious potential for medical and biotechnological applications. Here, we discuss the isolation of primary human B cells from both juvenile and adult tonsillar material using a two-step procedure based on gradient centrifugation followed by separation on a nylon wool column as alternative to the current gold standard, i.e., negative immunosorting from buffy coats by antibody-coated magnetic beads. We show that the nylon wool separation is a low-cost method well suited to the isolation of large amounts of primary B cells reaching purities ≥ 80%. More importantly, this method allows the preservation of all B cell subsets, while MACS sorting seems to be biased against a certain B cell subtype, namely the CD27+ B cells. Importantly, compared to blood, the excellent recovery yield during purification of tonsillar B cells provides high number of cells, hence increases the number of subsequent experiments feasible with identical cell material, consequently improving comparability of results. The cultivability of the isolated B cells was demonstrated using pokeweed mitogen (PWM) as a stimulatory substance. Our results showed for the first time that the proliferative response of tonsillar B cells to mitogens declines with the age of the donor. Furthermore, we observed that PWM treatment stimulates the proliferation of a dedicated subpopulation and induces some terminal differentiation with ASCs signatures. Taken together this indicates that the proposed isolation procedure preserves the proliferative capability as well as the differentiation capacity of the B cells.

Targeting XIAP for the treatment of malignancy.

X-linked inhibitor of apoptosis protein (XIAP) is a member of the inhibitor of apoptosis proteins family of caspase inhibitors that selectively binds and inhibits caspases-3, -7 and -9, but not caspase-8. As such, XIAP blocks a substantial portion of the apoptosis pathway and is an attractive target for novel therapeutic agents for the treatment of malignancy. Antisense oligonucleotides directed against XIAP are effective in vitro and are currently being evaluated in clinical trials. Small molecule XIAP inhibitors that target the baculovirus IAP repeat (BIR) 2 or BIR 3 domain are in preclinical development and are advancing toward the clinic. This review will discuss the progress being made in developing antisense and small-molecule XIAP inhibitors.

Activation of Src kinases p53/56lyn and p59hck by p210bcr/abl in myeloid cells.

Chronic myeloid leukemia is characterized by the Philadelphia (Ph1) translocation t(9;22) that generates a hybrid gene, bcr/abl, translated to a Mr210,000 tyrosine kinase (p210bcr/abl) with transforming activity for hematopoietic cells. Hematopoietic cell transformation by p2l0bcr/abl seems to involve activation of the Ras signaling pathway by at least two different signaling intermediates, growth factor receptor-bound protein 2 and Src homology and collagen protein, but additional signaling proteins are likely to be required as well. In an effort to identify additional phosphoproteins activated by p210bcr/abl, we studied the murine, interleukin 3-dependent, myeloid cell line, 32D, and a bcr/abl-transfected, factor-independent subline, 32Dp210. The analysis of whole-cell lysates of 32D and 32Dp210 cells showed that several proteins with a molecular weight of Mr50,000-60,000 were phosphorylated on tyrosine residues in 32Dp210 cells. Because Src family kinases have an apparent molecular weight of Mr50,000-60,000, we asked whether they could become activated by p2l0bcr/abl. Two Src family kinases, p53/56lyn and p59hck, showed a severalfold higher phosphokinase activity in 32Dp210 cells than in 32D cells. Coimmunoprecipitation experiments with anti-Lyn, anti-Hck, and anti-Abl antibodies demonstrated an intracellular association of p210bcr/abl with p53/56lyn and p59hck. Moreover, the phosphokinase activity of p53/56lyn was higher in bcr/abl-positive myeloid cell lines (K562, BV173, and LAMA84) than in the bcr/abl-negative myeloid cell line JOSK-M. In conclusion, the results show that p210bcr/abl induces the activation of at least two Src family kinases, P53/56lyn and p59hck, in myeloid cells. These findings extend the range of potential targets of p210bcr/abl that might mediate its transforming effects.

Some antagonists of platelet activating factor are cytotoxic for human malignant cell lines.

Nine new platelet activating factor (PAF) antagonists from 4 different chemical classes (thiopyrimidines: SDZ 59-015; thioimidazolines: SDZ 61-813; imidazoisoquinolines: SDZ 62-434, SDZ 62-759, SDZ 63-135, SDZ 63-596; and imidazopiperidines: SDZ 61-638, SDZ 62-293, SDZ 62-694) have been tested for cytostatic/antiproliferative ([3H]thymidine uptake) and cytotoxic (trypan blue dye exclusion) activity in neoplastic human cell lines of different histology in vitro. The antiproliferative activity of 3 of the 9 PAF antagonists (SDZ 61-638, SDZ 61-813, SDZ 62-694) was not stable after freezing and thawing. SDZ 59-015 showed only minor cytotoxic or antiproliferative effects in a dose range of 2-40 microns after 24, 48, and 72 h of incubation. SDZ 62-434 showed varying activity. There were no significant differences between the activities of the other 3 PAF antagonists from the imidazoisoquinoline class, which showed drug concentrations inhibiting 50% of the activity studied (IC50) and drug concentrations yielding a 50% decrease of trypan blue dye exclusion (LC50) of less than or equal to 20 microM at greater than or equal to 48 h, even in the K-562 cell line, which is known to be rather resistant for a variety of cytotoxic drugs related to PAF. SDZ 62-293 showed the best antineoplastic properties with IC50 and LC50 values less than or equal to 10 microM at greater than or equal to 48 h including K-562. SDZ 62-434, SDZ 62-759, SDZ 63-135, SDZ 63-596, and SDZ 62-293 have been further tested in a human tumor cloning assay in 5 cell lines. Colony formation was reproducibly suppressed to less than 30% of the controls only by SDZ 63-135 (less than or equal to 40 microM) and SDZ 62-293 (less than or equal to 20 microM) during continuous exposure. There was no correlation between the IC50 values for the antiproliferative activity of the test compounds and their IC50 values for PAF-induced human platelet aggregation. Furthermore, the antiproliferative activity of the most active compound, SDZ 62-293, could not be antagonized by preincubation with the specific PAF antagonists WEB 2170 or WEB 2086 or PAF itself in noncytotoxic doses.(ABSTRACT TRUNCATED AT 400 WORDS)

Spontaneous 24-h ghrelin secretion pattern in fasting subjects: maintenance of a meal-related pattern.

OBJECTIVE: Ghrelin stimulates GH release and causes weight gain through increased food intake and reduced fat utilization. Ghrelin levels were shown to rise in the preprandial period and decrease shortly after meal consumption, suggesting a role as a possible meal initiator. However, ghrelin secretion in fasting subjects has not yet been studied in detail. DESIGN: 24-h ghrelin profiles were studied in six healthy volunteers (three females; 25.5 years; body mass index 22.8 kg/m(2)) and compared with GH, insulin and glucose levels. METHODS: Blood samples were taken every 20 min during a 24-h fasting period and total ghrelin levels were measured by RIA using a polyclonal rabbit antibody. The circadian pattern of ghrelin secretion and pulsatility (Cluster analysis) were evaluated. RESULTS: An increase and spontaneous decrease in ghrelin were seen at the timepoints of customary meals. Ghrelin was secreted in a pulsatile manner with approximately 8 peaks/24 h. An overall decrease in ghrelin levels was observed during the study period. There was no correlation of ghrelin with GH, insulin or blood glucose levels. CONCLUSIONS: This pilot study indicates that fasting ghrelin profiles display a circadian pattern similar to that described in people eating three times per day. In a fasting condition, GH, insulin and glucose do not appear to be involved in ghrelin regulation. In addition, we found that ghrelin is secreted in a pulsatile pattern. The variation in ghrelin independently of meals in fasting subjects supports previous observations that it is the brain that is primarily involved in the regulation of meal initiation.

Mutational spectrum of steroid 21-hydroxylase and the genotype-phenotype association in Middle European patients with congenital adrenal hyperplasia.

OBJECTIVE: To analyze the mutational spectrum of steroid 21-hydroxylase (CYP21) and the genotype- phenotype correlation in patients with congenital adrenal hyperplasia (CAH) registered in the Middle European Society for Pediatric Endocrinology CAH database, and to design a reliable and rational approach for CYP21 mutation detection in Middle European populations. DESIGN AND METHODS: Molecular analysis of the CYP21 gene was performed in 432 CAH patients and 298 family members. Low-resolution genotyping was performed to detect the eight most common point mutations. High-resolution genotyping, including Southern blotting and sequencing was performed to detect CYP21 gene deletions, conversions, point mutations or other sequence changes. RESULTS: CYP21 gene deletion and In2 and Ile172Asn mutation accounted for 72.7% of the affected alleles in the whole study group. A good genotype-phenotype correlation was observed, with the exception of Ile172Asn and Pro30Leu mutations. In 37% of patients low resolution genotyping could not identify the causative mutation or distinguish homozygosity from hemizygosity. Using high-resolution genotyping, the causative mutations could be identified in 341 out of 348 analyzed patients. A novel mutation Gln315Stop was found in one simple virilising CAH (SV-CAH) patient from Austria. In the remaining seven patients polymorphisms were identified as the leading sequence alteration. The presence of elevated basal and ACTH-stimulated 17-hydroxyprogesterone, premature pubarche, advanced bone age and clitoral hypertrophy directly implicated Asn493Ser polymorphism in the manifestation of nonclassical- (NC) and even SV-CAH. CONCLUSIONS: By genotyping for the most common point mutations, CYP21 gene deletion/conversion and the 8 bp deletion in exon 3, it should be possible to identify the mutation in 94-99% of the diseased alleles in any investigated Middle European population. In patients with a mild form of the disease and no detectable mutation CYP21 gene polymorphisms should be considered as a plausible disease-causing mutation.

Therapeutic activity of 1-beta-D-arabinofuranosylcytosine conjugates of lipids in WEHI-3B leukemia in mice.

Two new conjugates of 1-beta-D-arabinofuranosylcytosine (ara-C) and lipids were tested for therapeutic activity in myelomonocytic WEHI-3B leukemia in mice. Both conjugates were superior to equimolar mixtures of their respective parent compounds and to ara-C alone. IP treatment was found effective after either IP or IV transplantation of the leukemia. The thioether-linked lipid conjugate ara-CDP-D,L-PTBA showed considerably higher efficacy than the ester-linked lipid conjugate ara-CDP-L-dipalmitin. The optimal therapeutic regimen of ara-CDP-D,L-PTBA consisted of 60 mg/kg given IP qd 1-5 after transplantation of the WEHI-3B leukemia.

Signal transduction of interleukin-6 involves tyrosine phosphorylation of multiple cytosolic proteins and activation of Src-family kinases Fyn, Hck, and Lyn in multiple myeloma cell lines.

Binding of interleukin-6 to its receptor (IL-6R) induces the association of the IL-6R alpha chain (IL-6Ralpha) with a 130-kDa transmembrane glycoprotein, gp130. This event activates tyrosine kinases of the Janus kinase (JAK) family and transduces signals to the cytosol or nucleus. To further characterize the biochemical mechanisms by which IL-6 promotes cell proliferation, we investigated the effects of IL-6 on the growth and transmembrane signaling of several lymphoid cell lines. In the IL-6-dependent cell line B-9, IL-6 induced a rapid, transient, and concentration-dependent tyrosine phosphorylation of several cytosolic proteins as detected by antiphosphotyrosine immunoblots. The molecular weight of major bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis was 44, 65, 70, 80, 137, 148, 184, and 190 kDa, respectively. Similar effects of IL-6 on tyrosine phosphorylation were observed in the human multiple myeloma cell line LP-1. Because JAKs were unlikely to mediate all the biological effects of IL-6, we investigated whether members of the Src family of tyrosine kinases were also activated in B-9 or LP-1 cells. IL-6 induced the activation and tyrosine phosphorylation of p59Fyn, p56/59Hck, and p56Lyn. Coprecipitation experiments with anti-Hck, anti-Lyn, anti-Fyn, and anti-gp130 antibodies revealed a physical association with gp130 of p56/59Hck and p56Lyn, but not p59Fyn, in LP-1 cells. Together, these results show for the first time that several Src kinases may become activated by IL-6 (p59Fyn, p56/59Hck, and p56Lyn) and associate with gp130 (p56/59Hck and p56Lyn).

Corticotropin-releasing hormone stimulation test before and after transsphenoidal selective microadenomectomy in 30 patients with Cushing's disease.

Thirty patients with ACTH-dependent Cushing's disease were tested with CRH before and 7-10 days and 3-6 months after selective transsphenoidal adenomectomy. In 28 of 30 patients an adenoma was found, and in 22 (79%) clinical and endocrinological remission occurred. Preoperatively, the majority of the patients had basal and CRH-stimulated plasma ACTH levels that were markedly increased compared to those in normal subjects. On the basis of the CRH stimulation test and low dose (2 mg) dexamethasone suppression test results 7-10 days after surgery, these 30 patients were divided into 4 groups. Groups I, II, and III were patients in remission, as defined by undetectable, subnormal, or normal basal plasma ACTH and cortisol levels in addition to sufficient suppression of cortisol (less than 2 micrograms/dL) during the low dose (2 mg) dexamethasone suppression test. Patients in group IV were not in remission. In group I (n = 6), CRH failed to raise undetectable basal ACTH levels in the early postoperative period; however, 3-6 months later plasma ACTH did increase in response to CRH. In group II (n = 11), undetectable or low basal ACTH levels increased after CRH, and the increase was similar to that in normal individuals. In group III (n = 5), basal ACTH levels were normal, and the response to CRH was exaggerated, but all patients responded normally to the dexamethasone suppression test. The CRH-induced ACTH increase in group III was significantly greater (P less than 0.003) than that in normal subjects, but was similar to that in patients not in remission in group IV (n = 6). Three to 6 months later, the ACTH response to CRH in group III was normal. In summary, the CRH test 7-10 days after surgery in patients with Cushing's disease indicated remission when there was no CRH-induced ACTH response or the response was normal (groups I and II). The test failed to predict remission in patients with an exaggerated CRH-induced ACTH response (groups III and IV). However, with regard to group II, the CRH-induced ACTH increase 1 week after selective adenomectomy indirectly supports the concept of CRH deficiency during hypercorticism and thus, in these patients as well as in group I, a pituitary origin of the disease.

Preclinical activity of taxotere (RP 56976, NSC 628503) against freshly explanted clonogenic human tumour cells: comparison with taxol and conventional antineoplastic agents.

Taxotere (TER) and taxol (TA) are new antitumour agents currently undergoing clinical evaluation. We studied the antineoplastic effects of these agents (final concentrations: 4.0, 0.4, 0.04 mumol/l) on the in vitro proliferation of clonogenic cells from freshly explanted human tumours using a capillary soft agar cloning system. We also compared the activity of these new compounds to conventional antineoplastic agents (bleomycin, cisplatin, dacarbazine, doxorubicin, etoposide, 5-fluorouracil, vinblastine, interferon-alpha 2). Using a 21-28-day continuous drug exposure, 54/81 specimens (67%) were evaluable for comparisons, and using a 1-h drug exposure followed by 21-28 days incubation, 50/80 specimens (63%) were similarly evaluable. With both schedules, TA and TER showed concentration-related antitumour activity. At 0.4 mumol/l, median colony survival was 0.61 x control (range 0.09-0.96) for TA and 0.51 x control (0.15-0.81) for TER in the 1-h incubation (P = 0.0002). Median colony formation was also reduced significantly more by TER as compared to TA in the long-term incubation schedule. Statistical analysis indicated that TER but not TA was significantly more active than cisplatin (P = 0.02), doxorubicin (P = 0.01), 5-fluorouracil (P = 0.01) and interferon-alpha 2 (P = 0.01). We conclude that TER and TA are more active against in vitro tumour colony formation from freshly explanted human tumours. TER appears to be slightly more active than taxol and promises to be active against tumours resistant to conventional antineoplastics.

Effects of hematopoietic growth factors on malignant nonhematopoietic cells.

We have assayed modulation of clonal growth of cell lines from human solid tumors in vitro by recombinant human interleukin-6 (rhIL-6), rhIL-3, rh granulocyte-macrophage colony-stimulating factor (GM-CSF), rhG-CSF, rhM-CSF, and rh erythropoietin. Effects of hematopoietic growth factors were also tested in the tritiated thymidine uptake assay. No reproducible and significant modulation of clonal growth was found with rhIL-6, rhM-CSF, and rhEPO. The other cytokines showed stimulation of colony formation in some cell lines from colorectal adenocarcinomas and bladder and lung cancers with the following order of activity: rhIL-3 greater than or equal to rhGM-CSF greater than rhG-CSF. Growth stimulation was only found in clonal assays; it was abolished by neutralizing antibodies and was highly dependent on culture conditions. Stimulation could be masked by elevation of serum concentration and there was an inverse correlation between spontaneous plating efficacy of the control cells and growth stimulation by the factor with the highest activity of the colony-stimulating factor at suboptimal growth conditions. Growth inhibition by the cytokines was not observed. We could not establish autocrine loops for the growth modulation by the cytokines in the cell lines tested so far. Furthermore, we xenotransplanted some responsive cell lines into athymic mice and observed their in vivo growth under systemic application of rhIL-3 and rhGM-CSF or vehicle. There was no significant alteration of the tumor growth by these cytokines at plasma levels sufficient for in vitro growth stimulation. In conclusion, tumor growth stimulation by rhGM-CSF and rhIL-3 as potential hazards for their clinical application in cancer patients in conjunction with cytotoxic chemotherapy is unlikely.

Enhanced activity of CMP-neuAc:Gal beta 1-4GlcNAc:alpha 2,6-sialyltransferase in metastasizing human colorectal tumor tissue and serum of tumor patients.

The activity of sialyltransferases with different linkage specificities, of a Gal beta 1-4GlcNAc:alpha 2,6-sialyltransferase and a Gal beta 1-4GlcNAc:alpha 2,3-sialyltransferase, was studied in human colorectal tumor tissue from surgical specimens, normal mucosa, liver and liver metastases, and serum of patients suffering from colorectal carcinomas. While alpha 2,3-specific activity was equally high in tumor and mucosa samples, the activity of the alpha 2,6-specific enzyme was increased in tumor tissue and particularly in metastasizing tumors. Also, compared to healthy individuals, serum of patients suffering from metastasizing tumors contained a significantly higher activity of the alpha 2,6-specific enzyme. These results demonstrate that specific sialyltransferase isoforms are expressed in metastasizing tumors and that determination of such isoforms may be a new means for tumor detection and monitoring.

Lack of therapeutic effects of platelet activating factor antagonists in WEHI-3B leukemia, human xenotransplanted colorectal and lung cancer and Lewis-lung tumor in vivo.

Four new antagonists of platelet activating factor (PAF) from two different chemical classes (imidazoisoquinolines: SDZ 62-434, SDZ 63-135, SDZ 62-759; imidazopiperidines: SDZ 62-293) were tested for in vivo therapeutic activity in various tumor models including the murine myelomonocytic leukemia WEHl-3B, xenografts of human colon (HTB 38) and lung (HTB 119) cancer cell lines and the murine Lewis-lung tumor. After intraperitoneal (i.p.) injection of 1 x 10(3), 5 x 10(3) and 1 x 10(4) WEHl-3B cells into Balb/c mice, the drugs were given per os (p.o.) or i.p. over 6-14 days. Drug doses were pushed to exceed the lethal dose for 10% of the animals (LD10) and ranged from 1 to 100 mg/kg daily for p.o. treatment and from 1 to 75 mg/kg daily for i.p. treatment. In the xenotransplants and the Lewis-lung tumor experiments, PAF antagonists were given i.p. to nude Balb/c and C57 Black mice after intracutaneous (i.c.) tumor cell inoculation. None of the four compounds induced reproducible prolongation of life span, significant numbers of long term survivors, reduction of tumor size, or delay of tumor growth in any of the therapeutic models. Oral SDZ 62-759 had some activity in experiments in which there was slow WEHl-38 tumor growth in the controls. Toxicity of equivalent drugs doses was higher in the i.p. than in the p.o. schedules.

Antitumoral activity of a xanthate compound. I. Cytotoxicity studies with neoplastic cell lines in vitro.

Xanthate derivatives were shown previously to display antitumor activity against transformed fibroblasts and lymphoma cells in combination with monocarboxylic acids [1]. Various malignant cell lines of human origin were treated in vitro to explore the range of antitumoral activity of the compounds. The combination of tricyclodecan-9-yl-xanthogenate (D 609) with undecanoic acid (C11) exerted dose dependent cytotoxic and antiproliferative effects on cell lines both from solid tumors (glioblastomas, colon-carcinomas) and hematological diseases (lymphomas, CML/BC). Additionally, the combination of D 609/C11 was able to kill both methotrexate- and adriamycin-resistant L 1210 and S 180 cells, indicating that there is no cross-resistance for these drugs and D 609/C11 in vitro.

Antitumoral activity of a xanthate compound. II. Therapeutic studies in murine leukemia and tumor models in vivo.

The combinations of tricyclodecan-9-yl-xanthogenate (D 609) with undecanoic acid (C11) and D 609 with myristic acid (C14) were tested in 3 rodent tumor models in vivo. D 609 in combination with C11 or C14 did not show antitumoral efficacy in 3-Lewis lung carcinoma (3-LL) growing in syngeneic C57BL6-mice (primary tumor and metastasis) or in WEHI-3B myelomonocytic leukemia growing in Balb/c mice, when given in a dose range lower than the lethal dose for 10% of the treated animals (LD10). In L 1210 mouse lymphoid leukemia growing in CD2F1 mice the combination of D 609/C11 given intraperitoneally in a concentration of 100 mg/kg for more than 1 day effected a significant difference in the survival curves between the control and therapeutic groups in 1 out of 2 experiments. In conclusion, the treatment schedules of D 609/C11 or D 609/C14 used in this study has not revealed significant therapeutic effects in mouse tumors or leukemias in vivo.

Cross-resistance pattern of cell lines selected for resistance towards different cytotoxic drugs to membrane-toxic phospholipids in vitro.

The synthetic ether lipids ET-18-OCH3 and BM41.440 and a derivative, hexadecylphosphocholine, were tested for inhibition of [3H]-thymidine uptake into a Chinese hamster ovarian cell line (AUXBl) and its multidrug-resistant subline selected for colchicine resistance (CHRC5). The activity of all three compounds against the multidrug-resistant subline was equal to or higher than that against the parent line. The same result was found for their activity against a human leukemic lymphoblastic cell line (CEM/O) and its methotrexate-resistant subline (CEM/MTX). In contrast, two multidrug-resistant cell lines selected for resistance to Adriamycin, the mouse leukemia cell line P388/ADR and the murine sarcoma cell line S180/ADR, expressed modest cross-resistance to the lipids as measured by thymidine uptake. Experiments performed using the trypan-blue dye-exclusion assay yielded comparable results, although this system revealed a slightly different sensitivity in showing the cytotoxicity of the drugs. By this assay, modest cross-resistance for ET-18-OCH3 and BM41.440 to Adriamycin was found only after 24 h incubation and decreased after 48 h incubation, with almost equal sensitivity to both drugs being shown by the parental (P388/W) and resistant lines (P388/ADR). Furthermore, findings from a human tumor-cloning assay were in accordance with these data, although they did not indicate cross-resistance for the P388/ADR cell line. These results suggest that certain ether lipids and derivatives might represent valuable anticancer drugs warranting further study in the setting of resistant disease.

Tenascin-C tissue concentration in inflammatory and neoplastic diseases of the colon mucosa.

BACKGROUND: Tenascin-C is a gycoprotein of the extracellular matrix with predominantly antiadhesive qualities. In the colon mucosa tenascin-C has been found to be induced in inflammatory and neoplastic diseases by immunohistology. This study aimed at quantitating mucosal tenascin-C induction. MATERIALS AND METHODS: Mucosal tenascin-C concentration was determined by Western blotting quantified by densitometry in fresh frozen specimens of the colon from patients with ulcerative colitis, familial polyposis, and colorectal carcinomas. RESULTS: The tenascin-C concentration in normal mucosa was 2.6 micrograms/mg protein (SD +/- 3.4 micrograms/mg). Colorectal adenomas displayed an equal tissue concentration of 2.8 micrograms/mg protein (SD +/- 2.0 micrograms/mg). In ulcerative colitis statistically significant elevated tissue content of 7.5 micrograms/mg protein (SD +/- 4.7 micrograms/mg) was found. Colorectal carcinomas had a tissue tenascin-C level of 18.0 micrograms/mg protein (SD +/- 14.6 micrograms/mg), which was significantly different from the other groups. CONCLUSIONS: Tenascin-C concentration is elevated in inflammatory and neoplastic diseases of the colorectal mucosa. The distinct increase in the tenascin-C content in colorectal carcinomas in contrast to normal levels in colorectal adenomas reflects an association of tenascin-C induction with malignant disease.