Successful xenografting of cryopreserved primary pancreatic cancers

In order to assess the suitability of cryopreserved neoplastic tissues for xenografting into nude (nu/nu) mice, we compared the take rate in 28 samples of pancreatic ductal carcinoma. Eleven fresh samples were implanted in nu/nu mice, and 17 were frozen in cryopreserving solution and implanted at a later time. All samples were examined for the presence of neoplastic tissue in cryostat sections. A total of 15 tumors grew in the animals; five from the freshly implanted samples and ten from those cryopreserved. Ten xenografted tumors were characterized for alterations in p53, K-ras, and p16 genes, which were found in six, eight, and nine cases, respectively. Our results demonstrate that the take rate for xenografting is comparable between cryopreserved and fresh tissue samples. The procedure allows for the exchange of tumor material between institutions and permits the establishment of centralized facilities for the storage of an array of different primary tumor samples suitable for the production of in vivo models of cancers.     

Differential modulation of mediator release from human basophils and mast cells by mizolastine

BACKGROUND: Basophils and mast cells play a major role in the pathogenesis of allergic disorders by releasing several proinflammatory mediators. Some histamine H1 receptor antagonists exert anti-inflammatory activities by modulating mediator release from basophils and mast cells. OBJECTIVE: To study the in vitro effects of mizolastine, an H1 receptor antagonist, on the release of eicosanoids, histamine and IL-4 from human basophils and lung mast cells. METHODS AND RESULTS: Mizolastine (10(-7)-10(-5) M) concentration-dependently inhibited the release of cysteinyl leukotriene C4 from anti-IgE-stimulated basophils (IC(50): 3.85+/-0.28 microM) and mast cells (IC(50): 3.92+/-0.41 microM). The same concentrations of mizolastine did not affect anti-IgE-induced prostaglandin D2 release from lung mast cells. In contrast, mizolastine enhanced up to 80% IgE-mediated histamine release (EC(50): 4.63+/-0.14 microM) from basophils, but not from mast cells and it significantly potentiated IL-4 release from basophils induced by anti-IgE. Mizolastine did not affect histamine release from basophils induced by formyl peptide, whereas it inhibited cysteinyl leukotriene C4 release (IC(50): 1.86+/-0.24 microM). Blockade of cytosolic phospholipase A2 and arachidonic acid mobilization by pyrrolidine-1 did not alter the effect of mizolastine on histamine release from basophils, thereby excluding accumulation of arachidonic acid metabolic intermediates as the cause of this effect. Mizolastine did not influence anti-IgE-induced activation of extracellular signal-regulated kinase-1 and -2 (ERK-1 and -2) in human basophils. CONCLUSIONS: Mizolastine efficiently inhibits LTC4 synthesis in human basophils and mast cells presumably by interfering with 5-lipoxygenase. In contrast, it enhances histamine and IL-4 release only from anti-IgE-stimulated basophils. Therefore, mizolastine differentially regulates the production of mediators from basophils and mast cells in a cell- and stimulus-specific fashion.     

Inhibition of IgE-mediated release of histamine and peptide leukotriene from human basophils and mast cells by forskolin

Forskolin, a diterpene compound isolated from the roots of Coleus forskohlii, activates adenylate cyclase in membranes from a variety of mammalian tissues. We found that forskolin (10(-7) to 3 X 10(-5) M) caused a concentration-related inhibition of IgE-mediated release of histamine and peptide leukotriene C4 (LTC4) from human basophils and lung mast cells. There was a significant linear correlation between the per cent inhibition of histamine and LTC4 release from both cell types. However, in both systems forskolin exerted a significantly greater inhibitory effect on LTC4 release than on histamine release. The concentration-response inhibition curve was paralleled by a forskolin-induced rise in cAMP levels in human leukocyte and mast cell preparations. The relationship between the effect of forskolin and the cAMP concentration was supported by the finding that forskolin inhibited the "first stage" of antigen-induced histamine release, but not the release caused by the Ca2+ ionophore, A23187. Propranolol, a competitive beta-receptor antagonist, did not block the inhibition of mediator release or the cAMP accumulation caused by forskolin. These data suggest that forskolin modulates the release of mediators of immediate hypersensitivity reactions via the activation of adenylate cyclase in human basophils and mast cells.     

Pharmacokinetics of high doses of piretanide in moderate to severe renal failure

Summary The pharmacokinetics of piretanide was studied in 10 patients with chronic renal failure. After administration of a high oral dose (12 to 192 mg) of piretanide the kinetics behaved according to an open 2-compartment model. The elimination constant in the first phase () ranged from 0.385 to 0.756 h^–1 and in the second phase () from 0.079 to 0.274 h^–1. The corresponding elimination half-lives ranged from 55 to 108 min (t_1/2 ) and from 152 to 524 min (t_1/2 ). Only an average of 2.8% of the orally administered drug was recovered in 24 h urines. Nevertheless, a good correlation was found between urinary recovery or renal clearance of the drug and residual renal function. The elimination of piretanide by non-renal mechanisms appeared to be increased when renal function was greatly diminished.     

Interspecies pharmacokinetic comparisons and allometric scaling of napsagatran, a low molecular weight thrombin inhibitor

The objective of this work was to assess the pharmacokinetics of napsagatran, a low molecular weight thrombin inhibitor, after intravenous administration in a variety of laboratory animals, and prospectively to help design the first pharmacokinetic studies in man. Napsagatran is actively excreted into the bile and urine of various species and pronounced species-differences in its pharmacokinetics are observed. It is, therefore, an interesting compound to use in tests of the limitations of presently available inter-species scaling methods. The present data suggest that allometric exponent values which are consistent with the values expected for physiological processes and small organic molecules are not necessarily associated with successful predictions in man when active transport processes are involved in the disposition of the compounds. For example, compared with the values observed in man, the clearance (CL), non-renal clearance (CL(nr)) and the volume of distribution at steady state (Vd(ss)) were over-predicted by 3-, 7- and 2-fold, respectively, by use of allometry. Of the species tested, the cynomolgus monkey seemed to be the most useful for predicting kinetics in man when the approach based on concentration-time transformations was used. Thus, for half-life (t(1/2)), CL and Vd(ss), the observed mean values of 1.7 h, 459 mL min(-1) and 24 L kg(-1) in man were very close to the values predicted from the cynomolgus monkey (1.7 h, 652 mL min(-1) and 22 L kg(-1), respectively). The results show that there are large inter-species differences for kidney and liver excretion of napsagatran. This is probably because of the involvement of active transport processes, which compromised the kinetic extrapolation from animal to man, although a more thorough investigation of the transporters involved in the disposition of napsagatran is necessary to enable better understanding of the species differences observed.     

Clinical relevance of different sequencing of doxorubicin and cyclophosphamide, methotrexate, and Fluorouracil in operable breast cancer.

PURPOSE: To assess the clinical relevance of different sequences of doxorubicin (DOX) and cyclophosphamide, methotrexate, and fluorouracil (CMF) in patients with operable breast cancer at risk of disease relapse. PATIENTS AND METHODS: Two randomized trials were activated in the early 1980s. The first study, in patients with one to three involved nodes, was intended to assess the effectiveness of intravenous (i.v.) CMF given every 3 weeks for 12 courses versus eight courses of the same CMF regimen followed by four courses of full-dose DOX (CMF-->DOX). The second study, in patients with more than three involved nodes, compared four courses of full-dose DOX sequentially followed by eight courses of i.v. CMF (DOX-->CMF) versus alternating two courses of the same CMF regimen with one course of DOX (CMF/DOX) for a total of 12 courses. RESULTS: After a median observation of 210 months, no statistically significant difference was documented in the first study (relapse-free survival hazard rate [HR], 1.06; total survival HR, 1.03). In contrast, the delivery of DOX first, followed by CMF significantly reduced the risk of disease relapse (HR, 0.68; 95% CI, 0.54 to 0.87; P =.0017) and death (HR, 0.74; 95% CI, 0.57 to 0.95; P =.018) compared with the alternating regimen. CONCLUSION: Anthracycline-containing regimens can further reduce the odds of relapse and death compared with CMF. However, the findings observed in our trials emphasize that the relative merits of anthracycline adjuvant programs also can depend on the modality of administration and must be assessed in properly designed trials in which the magnitude of the benefits can be weighed against potential risks.     

Dual Action of NAMI-A in inhibition of solid tumor metastasis: selective targeting of metastatic cells and binding to collagen.

NAMI-A is a ruthenium complex endowed with a selective effect on lung metastases of solid metastasizing tumors. The aim of this study is to provide evidence that NAMI-A's effect is based on the selective sensitivity of the metastasis cell, as compared with other tumor cells, and to show that lungs represent a privileged site for the antimetastatic effects. The transplantation of Lewis lung carcinoma cells, harvested from the primary tumor of mice treated with 35 mg/kg/day NAMI-A for six consecutive days, a dose active on metastases, shows no change in primary tumor take and growth but a significant reduction in formation of spontaneous lung metastases. Transmission electron microscopy examination of lungs and kidney shows NAMI-A to selectively bind collagen of the lung extracellular matrix and also type IV collagen of the basement membrane of kidney glomeruli. The half lifetime of NAMI-A elimination from the lungs is longer than for liver, kidney, and primary tumor. NAMI-A bound to collagen is active on tumor cells as shown in vitro by an invasion test, using a modified Boyden chamber and Matrigel, and it inhibits the matrix metallo-proteinases MMP-2 and MMP-9 at micromolar concentrations, as shown in vitro by a zimography test. These data show NAMI-A to significantly affect tumor cells with metastatic ability. Binding to collagen allows NAMI-A to exert its selective activity on metastatic cells during dissemination and particularly in the lungs. These data also stress the wide spectrum of daily doses and treatment schedules at which NAMI-A is active against metastases.     

Expression of Epstein-Barr virus latent membrane protein-1 in Hodgkin and Reed-Sternberg cells of classical Hodgkin's lymphoma: associations with presenting features, serum interleukin 10 levels, and clinical outcome.

PURPOSE: EBV-latent membrane protein-1 (LMP-1) is often expressed in Hodgkin and Reed-Sternberg (HRS) cells of classical Hodgkin's lymphoma (cHL), but its clinical significance is controversial. We correlated LMP-1 with presenting features, including serum interleukin 10 levels and clinical outcome. EXPERIMENTAL DESIGN: Patients were eligible if they had biopsy-proven cHL, were untreated, HIV-1 negative, and had available archival tissue. LMP-1 expression was determined by immunohistochemistry. RESULTS: We identified 577 patients with cHL with a median age of 30 years, 55% of whom were male. LMP-1 was expressed in HRS cells of 124 patients (21%) and was detected in 78 of 461 (17%) patients with nodular sclerosis compared with 44 of 112 (39%) with mixed cellularity (P < 0.001 by Fisher's exact test). Patients with tumors with LMP-1-positive HRS cells had higher serum interleukin 10 levels (P = 0.009 by Mann-Whitney test). For the 303 patients treated with doxorubicin, bleomycin, vinblastine, and dacarbazine or equivalent regimens, the 5-year failure-free survival (FFS) for those with LMP-1-positive tumors was 74% compared with 81% for those with LMP-1-negative tumors (P = 0.23, by log-rank test). Overall survival (OS) at 5 years for patients with LMP-1-positive tumors was 90 versus 91% for patients with LMP-1-negative tumors (P = 0.8 by log-rank test). Expression of LMP-1 was not associated with different FFS and OS in patients treated with other regimens or with radiotherapy alone. CONCLUSIONS: LMP-1 was expressed by HRS cells in 21% of cHL and correlated with mixed cellularity type and higher serum interleukin 10 levels. The presence of LMP-1 was not associated with FFS or OS in uniformly treated patients.     

Frequent loss of expression of the cyclin-dependent kinase inhibitor p27(Kip1) in estrogen-related Endometrial adenocarcinomas.

PURPOSE: p27(Kip1) is a member of the Cip1/Kip1 family of cyclin-dependent kinase inhibitors and is a potential tumor suppressor gene. Low levels of p27 are associated with poor prognosis in a variety of gynecological tumors, including breast, ovarian, and cervical carcinomas. The role of p27 in endometrial cancer remains controversial. EXPERIMENTAL DESIGN: In the present study, p27 protein expression was investigated by immunohistochemistry in a series of 217 endometrial adenocarcinomas and, where present, in synchronous normal endometrium, simple and complex hyperplasia (with or without atypia), and cystic atrophy. The relationship between p27 expression and clinical outcome was also evaluated. RESULTS: Immunohistochemical analysis revealed a significant loss of p27 expression from normal (33%) through hyperplastic endometrium (50%) to endometrial adenocarcinomas (71%; P 相似文献