Histological Classification and Immunohistochemical Evaluation of MDM2 and CDK4 Expression in Canine Liposarcoma.

Canine liposarcoma is an uncommon soft tissue sarcoma usually arising in the subcutis. While liposarcoma classification in dogs is based solely on histology, in humans it depends on the detection of genetic abnormalities that can lead to specific protein overexpression. This study is an immunohistochemical evaluation of MDM2 and CDK4 expression in canine liposarcoma designed to assess the correlation of these proteins with histologic type, grade, mitotic index and Ki67 labeling index and evaluate their utility in improving tumor classification. Fifty-three liposarcomas were retrospectively collected: 24 were well differentiated liposarcomas (WDL), 16 of which expressed MDM2 and 21 CDK4; 7 were myxoid liposarcomas (ML), 1 of which expressed MDM2 and 5 expressed CDK4; 18 were pleomorphic liposarcomas (PL), all were MDM2 negative and 12 expressed CDK4. Four tumors were morphologically consistent with dedifferentiated liposarcoma (DDL) a subtype described only in humans: 3 expressed MDM2 and 4 expressed CDK4. MDM2 expression correlated with histotype (highly expressed in WDL and DDL) and grade (highly expressed in grade 1 tumors). Histotype correlated with the Ki67 labeling index (lowest in WDL and highest in DDL). A revised classification, considering MDM2 expression, allowed 8 WDL to be reclassified as PL and correlated significantly with mitotic and Ki67 labeling index (both significantly lower in WDL and progressively higher in ML and DDL). These results partially parallel data reported for human liposarcomas, suggesting that WDL and DDL are distinct neoplastic entities characterized by MDM2 expression, which may represent a useful diagnostic and potentially prognostic marker for canine liposarcoma.

Can Microfiltered Seminal Plasma Preserve the Morphofunctional Characteristics of Porcine Spermatozoa in the Absence of Antibiotics? A Preliminary Study.

Artificial insemination is extensively performed in pig farms in Europe, the United States and Canada. Antibiotics are typically added to the inseminating dose to limit bacterial growth during liquid phase storage at 16°C, as bacterial contamination is unavoidable. The World Organization for Animal Health (OIE) and the Food and Agriculture Organization (FAO) take action to control and reduce antibiotic use in animals as more bacteria are becoming resistant to antimicrobials. To avoid the use of antibiotics, we prepared inseminating doses using microfiltered seminal plasma (SP). Microfiltration is a common technology used to reduce bacterial contamination but may retain seminal substances, influencing sperm quality during storage. Therefore, the aim of this study was to evaluate the morphofunctional parameters of spermatozoa during storage at 16°C in doses prepared with or without microfiltered SP, with or without the addition of antibiotics, in a Latin square design. Artificial insemination doses with microfiltered SP and without antibiotic addition preserved spermatozoa viability, mitochondrial membrane potential, acrosome integrity and objective motility, with absolute values equal or even better than those observed in conventional doses. In conclusion, although the results could be considered preliminary due to the small sample size, this study suggests that microfiltration of SP can be a simple method, feasible on farms, to replace antibiotic use in extended doses stored in the liquid phase at 16°C for up to 7 days.

Differential expression of CD90 and CD14 stem cell markers in malignant breast cancer cell lines.

The recently emerged concept of cancer stem cell (CSC) has led to a new hypothesis on the basis for tumor progression. Basically, the CSC theory hypothesizes the presence of a hierarchically organized and relatively rare cell population, which is responsible for tumor initiation, self-renewal, and maintenance, in addition to accumulation of mutation and resistance to chemotherapy. CSCs have recently been described in breast cancer. Different genetic markers have been used to isolate breast CSCs, none of which have been correlated with the tumorigenicity or metastatic potential of the cells, limiting their precise characterization and clinical application in the development of therapeutic protocols. Here, we sought for subpopulations of CSCs by analyzing 10 judiciously chosen stem cell markers in a normal breast cell line (MCF10-A) and in four human breast cancer cell lines (MCF-7, MDA-MB-231, MDA-MB-435, and Hs578-T) displaying different degrees of metastatic and invasiveness potential. We were able to identify two markers, which are differentially expressed in nontumorigenic versus tumor cells. The CD90 marker was highly expressed in the malignant cell lines. Interestingly, the CD14 molecule displayed higher expression levels in the nontumorigenic cell line. Therefore, we demonstrated that these two markers, which are more commonly used to isolate and characterize stem cells, are differentially expressed in breast tumor cells, when compared with nontumorigenic breast cells.

Initial ontogeny of digestive enzymes in the early life stages of captive-bred European eels during fasting: A partial characterization.

The European eel has recently been included on the Red List of the International Union for Conservation of Nature (IUCN) as a critically endangered species. The rearing of Anguilla larvae is seen as a key bottleneck to the mass production of glass eels since very little ecological information is available regarding their natural nutrition. Studies of digestive physiology and ontogenetic development in eel larvae could provide useful information for solving some of the puzzles regarding larval fish culture. The aim of this study was to characterize the ontogeny of pancreatic enzymes (trypsin, lipase and amylase) and a peptide hormone regulator of pancreatic secretion (cholecystokinin) in terms of gene expression in European eel larvae from day 0 (P0) of hatching to 5, 10, 15 and 20 days post hatching during fasting. The results in the present study showed that all the genes selected were present, with different levels of expression and increasing trends, during larval development. At P0, the increase in the gene expression of lipase and amylase was higher than that of trypsin and cholecystokinin, confirming that enzymatic activity began before mouth opening and that larvae, provided with a complete enzymatic set, might have the capacity of digesting and absorbing various nutrients.

Laboratory animal science: a resource to improve the quality of science.

The contribution of animal experimentation to biomedical research is of undoubted value, nevertheless the real usefulness of animal models is still being hotly debated. Laboratory Animal Science is a multidisciplinary approach to humane animal experimentation that allows the choice of the correct animal model and the collection of unbiased data. Refinement, Reduction and Replacement, the "3Rs rule", are now widely accepted and have a major influence on animal experimentation procedures. Refinement, namely any decrease in the incidence or severity of inhumane procedures applied to animals, has been today extended to the entire lives of the experimental animals. Reduction of the number of animals used to obtain statistically significant data may be achieved by improving experimental design and statistical analysis of data. Replacement refers to the development of validated alternative methods. A Laboratory Animal Science training program in biomedical degrees can promote the 3Rs and improve the welfare of laboratory animals as well as the quality of science with ethical, scientific and economic advantages complying with the European requirement that "persons who carry out, take part in, or supervise procedures on animals, or take care of animals used in procedures, shall have had appropriate education and training".

Relative abundance of heat shock proteins and clusterin transcripts in spermatozoa collected from boar routinely utilised in an artificial insemination centre: preliminary results.

It is widely accepted that mature sperm contains RNA. The first hypothesis was that sperm RNAs have no functions of their own but are simply residues of spermatogenesis reflecting the events that occurred during their formation in the testes. More recently new discoveries have essentially expanded these views, showing that sperm mRNAs constitute a population of stable full-length transcripts, many of which are selectively retained during spermatogenesis and delivered to oocytes contributing to early embryo development. It is well known that semen quality can be influenced by occasional physical stress, infection, and variation in temperature and the definition of new markers for evaluation of semen could offer knowledge about the fertility potential of a semen sample. The aim of the present study was to evaluate the presence and the relative quantity of transcripts and protein of heat shock protein 70 (HSP70), 90 (HSP90) and clusterin (CLU) in Percoll-selected spermatozoa collected from seven adult boars of proven fertility routinely employed for artificial insemination. Our results showed the presence of HSP70, HSP90 and CLU transcripts with different level of expression: high for HSPs and low for CLU transcripts. The transcript level of both HSPs are similar among selected spermatozoa derived from high quality sperm with the exception of one boar that showed a reduced content of HSP70 and HSP90 mRNA together with a lower semen quality. At protein level, both HSPs were detected with similar amount among all seven boars whilst no band was evidenced for CLU protein.

Familial tumoral calcinosis and testicular microlithiasis associated with a new mutation of GALNT3 in a white family.

BACKGROUND: Familial tumoral calcinosis (FTC) is a rare autosomal recessive disease characterised by the development of multiple calcified masses in periarticular soft tissues; GALNT3 gene mutations have recently been described in an African American and in a Druse Arab family with FTC. OBJECTIVE: To report the clinical and histological features caused by a new GALNT3 mutation in a white family. RESULTS: Homozygosity for the nonsense mutation Lys463X was found in both affected siblings, who displayed a classic phenotype, the male also having testicular microlithiasis. He is the first subject described with testicular microlithiasis in FTC. CONCLUSIONS: The high testicular expression of GALNT3 suggests that the gene alteration could act locally by causing deposition of calcium, and the testis may be an underestimated site of calcification in FTC. Autoimmune diseases are present in several members of the family. Although immune disorders have been described in FTC, autoimmunity does not segregate with the GALNT3 mutation in this family.

Carbon monoxide pretreatment prevents respiratory derangement and ameliorates hyperacute endotoxic shock in pigs.

Endotoxic shock, one of the most prominent causes of mortality in intensive care units, is characterized by pulmonary hypertension, systemic hypotension, heart failure, widespread endothelial activation/injury, and clotting culminating in disseminated intravascular coagulation and multi-organ system failure. In the last few years, studies in rodents have shown that administration of low concentrations of carbon monoxide (CO) exerts potent therapeutic effects in a variety of diseases/disorders. In this study, we have administered CO (one our pretreatment at 250 ppm) in a clinically relevant, well-characterized model of LPS-induced acute lung injury in pigs. Pretreatment only with inhaled CO significantly ameliorated several of the acute pathological changes induced by endotoxic shock. In terms of lung physiology, CO pretreatment corrected the LPS-induced changes in resistance and compliance and improved the derangement in pulmonary gas exchange. In terms of coagulation and inflammation, CO reduced the development of disseminated intravascular coagulation and completely suppressed serum levels of the proinflammatory IL-1beta in response to LPS, while augmenting the anti-inflammatory cytokine IL-10. Moreover, the effects of CO blunted the deterioration of kidney and liver function, suggesting a beneficial effect in terms of end organ damage associated with endotoxic shock. Lastly, CO pretreatment prevents LPS-induced ICAM expression on lung endothelium and inhibits leukocyte marginalization on lung parenchyma.

Transduction of the IL2 gene into human acute leukemia cells: induction of tumor rejection without modifying cell proliferation and IL2 receptor expression.

BACKGROUND: Previous studies have suggested that some of the limitations associated with the administration of high-dose exogenous interleukin 2 (IL2) may be overcome, at least partly, by cytokine gene transfer modalities. These findings have prompted investigations into whether human tumor cells may be transduced with the IL2 gene and whether tumor cell lines could be engineered to release IL2. PURPOSE: The purpose of this study was to evaluate the possibility of inducing a productive transfer of the IL2 gene into human acute leukemia cells and to assess the phenotypic and proliferative changes generated in the engineered cells, as well as their tumorigenic potential in nude mice. METHODS: Three retroviral vectors (DC/TK/IL2, DC/AD/R/IL2, and N2/CMV/IL2) carrying the IL2 gene were used to transduce three human leukemic cell lines: K562 and U937 (myeloid) and ST4 (lymphoid). Messenger RNA expression of the IL2 gene was analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) and productive IL2 release using a human IL2 assay and an enzyme-linked immunosorbent assay kit. The expression of the p55 (alpha) and p75 (beta) chains of the IL2 receptor were determined by RT-PCR and indirect immunofluorescence. The kinetics of in vitro growth and proliferation of parental and engineered cells were also measured. Parental and IL2 gene-transduced ST4 lymphoblasts were injected into immunosuppressed nude mice that had their tumors measured twice weekly. RESULTS: The productive insertion of the IL2 gene was achieved in all three cell lines studied. The amounts of IL2 constitutively released by the engineered neoplastic cells ranged between 1 and 11 U/mL of IL2 produced from 10(6) cells in 72 hours. A fivefold increase in IL2 production was obtained in ST4 cells by further limiting dilution cloning of the bulk-infected cells. The stable integration of the IL2 gene did not modify the phenotype of the leukemic cells, the expression of the IL2 receptor alpha and beta chains and of several cytokine genes, or the kinetics of in vitro growth and proliferation. In nude mice injected with various IL2-producing ST4 clones, tumor growth associated inversely with the amounts of IL2 secreted by the leukemic cells. CONCLUSIONS: The results of this study demonstrate that the IL2 gene can be productively transduced into human myeloid and lymphoid leukemic cells without modifying their phenotypic and proliferative properties and that this transduction leads to a reduced or abrogated in vivo tumorigenic potential.

A new childhood T-cell lymphoma established in nude mice and in vitro.

A T-lymphoma cell line was established from a lymph node biopsy of a boy currently alive in complete remission. Neoplastic cells from this biopsy did not grow in vitro, whereas they formed a progressively growing s.c. tumor in splenectomized and sublethally irradiated nude mice and became serially transplantable in splenectomized and sublethally irradiated nude mice with a stable latency time. After the fourth transplant, cells were stored in liquid nitrogen and referred to as ST-4 cells. ST-4 cells display a membrane phenotype and a karyotype similar to that of the biopsy cells. After thawing, ST-4 cells grow both in splenectomized and sublethally irradiated nude mice and in vitro. They do not secrete interferon or interleukin 2, do not have natural killer activity, and do not respond to mitogen or alloantigen stimulation. The stable features of these T-lymphoma cells and the availability of normal autologous lymphocytes from the patient make this in vivo system quite unique and of importance for studies in tumor immunotherapy.

Protective and curative potential of vaccination with interleukin-2-gene-transfected cells from a spontaneous mouse mammary adenocarcinoma.

The potential of interleukin 2-gene-transfected tumor cells to prevent tumor growth and cure established tumors was evaluated using cells from a spontaneous, invasive, and metastasizing mouse mammary adenocarcinoma. Tumor cells engineered to secrete interleukin 2 initially trigger a local inflammatory reaction that leads to inhibition of established parental adenocarcinomas, as well as an antigenically unrelated fibrosarcoma. The ensuing systemic immunity selectively inhibits subsequent parental cell challenges and cures established parental adenocarcinomas and their lung metastases, although less effectively as the neoplastic mass increases. Multiple injections of interleukin 2-gene-transfected tumor cells may thus be considered a new form of vaccination in the management of minimal residual disease and incipient metastases.

Phase I and pharmacokinetic study of the camptothecin derivative irinotecan, administered on a weekly schedule in cancer patients.

Irinotecan (CPT-11) is a novel water-soluble, semisynthetic derivative of camptothecin, with inhibitory effects on mammalian DNA topoisomerase I, high cytotoxic activity in vitro and anticancer activity in animal models. Fifty-nine patients, with cancer refractory to conventional therapy, were entered in this phase I study, using a weekly schedule administration. A total of 304 weekly doses were administered at dose levels ranging from 50 to 145 mg/m2 (30-90 min i.v. infusion). Leukoneutropenia and diarrhea were the dose-limiting toxicities and appeared to be dose related, reversible and noncumulative. However, interpatient variability of toxic effects was substantial. Prolongation of the infusion time from 30 min to 90 min appeared to decrease the diarrhea. Other toxicities included moderate emesis, asthenia, alopecia, abdominal pain, and anemia. CPT-11 plasma disposition was bi- or triphasic with a terminal half-life of 9.3 h. CPT-11 area under the plasma concentration versus time curves increased linearly with dose (r = 0.47, P < 0.01). The active metabolite area under the plasma concentration versus time curve correlated significantly with that of CPT-11, but not with that of CPT-11 dose. Both CPT-11 and 7-ethyl-10-hydroxycamptothecin areas under the plasma concentration versus time curve correlated significantly with leukoneutropenia and diarrhea. One partial and 4 minor responses were observed at dose levels of 130 and 145 mg/m2. Using this weekly schedule, recommended doses for phase II studies are 100 mg/m2 in high risk patients and 115 mg/m2 in others.

Immunizing and curative potential of replicating and nonreplicating murine mammary adenocarcinoma cells engineered with interleukin (IL)-2, IL-4, IL-6, IL-7, IL-10, tumor necrosis factor alpha, granulocyte-macrophage colony-stimulating factor, and gamma-interferon gene or admixed with conventional adjuvants.

To evaluate the efficacy of vaccinations with cytokine-gene-transduced tumor cells, BALB/c mice were challenged with 1 x 10(5) parental cells of a syngeneic adenocarcinoma cell line (TSA-pc). No protection was observed in mice immunized 30 days earlier with 1 x 10(5) nonreplicating mitomycin-C-treated TSA-pc alone, or with Corynebacterium parvum or Complete Freund Adjuvant (CFA). Ten to 30% of mice immunized with nonreplicating cells engineered to produce interleukin (IL)-2, IL-4, IL-6, IL-7, IL-10, tumor necrosis factor alpha, granulocyte-macrophage colony-stimulating factor, and gamma-interferon gene were protected. Fifty % of mice immunized with replicating TSA-pc admixed with C. parvum and 80-100% of mice immunized with replicating tumor cells transduced with IL-2, IL-4, IL-7, IL-10, or gamma-interferon gene were protected. No cure was afforded by TSA cells admixed with C. parvum or CFA, nor by TSA cells engineered with IL-6, granulocyte-macrophage colony-stimulating factor, and tumor necrosis factor alpha gene injected starting 1 day after TSA-pc challenge. Complete tumor regression, however, was obtained in 10-20% of mice treated with TSA cells transduced with IL-2, IL-4, IL-7, or IL-10 and in 30% of those treated with TSA cells transduced with gamma-interferon gene.

Tumor localization in patients by radiolabeled monoclonal antibodies against colon carcinoma.

A radiolabeled monoclonal antibody (MAb) that has been shown to react specifically in vitro and ex vivo to human colorectal carcinoma and to inhibit growth of human carcinomas grafted in nude mice was administered to 52 colorectal carcinoma patients and 15 patients with other types of cancer. Of 63 colorectal carcinoma tumor sites studied, 34 showed significant accumulation of antibody by external photoscanning and tomoscintigraphy, whereas none of the 20 sites of other cancer types gave positive results. One-third of the patients received F(ab')2 fragments of the MAb, which gave a slightly higher percentage (61%) of positive results than did intact MAbs (51%). A few patients scheduled for tumor resection were given injections simultaneously of 131I-labeled MAb and 125I-labeled normal immunoglobulin G. Antibody concentration in resected tumors was 3.6 to 6.3 times higher than the average antibody concentration in adjacent normal tissues (1.5, 3.4, and 9.4 as compared with normal mucosa, serosa, and fat, respectively), and the specificity indices, calculated by differential radioactivity analysis, ranged from 2.1 to 5.1. The results show the potential value and limitations of this particular MAb for tumor detection by immunoscintigraphy.

Life cycle assessment and economic analysis of a low concentrating photovoltaic system.

Many new photovoltaic (PV) applications, such as the concentrating PV (CPV) systems, are appearing on the market. The main characteristic of CPV systems is to concentrate sunlight on a receiver by means of optical devices and to decrease the solar cells area required. A low CPV (LCPV) system allows optimizing the PV effect with high increase of generated electric power as well as decrease of active surface area. In this paper, an economic analysis and a life cycle assessment (LCA) study of a particular LCPV scheme is presented and its environmental impacts are compared with those of a PV traditional system. The LCA study was performed with the software tool SimaPro 8.0.2, using the Econinvent 3.1 database. A functional unit of 1 kWh of electricity produced was chosen. Carbon Footprint, Ecological Footprint and ReCiPe 2008 were the methods used to assess the environmental impacts of the LCPV plant compared with a corresponding traditional system. All the methods demonstrated the environmental convenience of the LCPV system. The innovative system allowed saving 16.9% of CO2 equivalent in comparison with the traditional PV plant. The environmental impacts saving was 17% in terms of Ecological Footprint, and, finally, 15.8% with the ReCiPe method.

Embelin supplementation of in vitro maturation medium does not influence nuclear and cytoplasmic maturation of pig oocytes.

Oxidative stress caused from in vitro culture contributes to inadequate oocyte maturation which leads to a poor embryo development. Therefore, it is important to protect oocytes and embryos against oxidative stress. This study was aimed at evaluating the effect of Embelin (2,5-dihydroxy-3-undecyl-1,4-benzoquinone), an antioxidant with various pharmacologic activities, on nuclear and cytoplasmic maturation of pig oocytes as well as on steroidogenesis of cumulus cells (CCs). Another objective was to determine the influence of Embelin on developmental competence of pig oocytes as well as the expression levels of three key genes (Nanog, Sox2 and Oct4) involved in the control of pluripotency in parthenogenetically activated embryos. Embelin (0, 10, 20 and 40 µM) was added during in vitro maturation of cumulus oocyte complexes; media of both the first and the second day of culture were collected and assayed for progesterone and estradiol-17ß. At the end of the maturation period, the oocytes were fixed (to determine nuclear maturation) or partenogenically activated to evaluate cytoplasmic maturation and genes expression. Embelin did not exert any effect on the proportion of MII oocytes, steroidogenesis of CCs, percentage of embryos that developed to blastocyst stage and the number of blastomeres/blastocyst. Moreover, no significant differences of Oct4, Nanog and Sox2 transcripts were detected in blastocyst stage embryos. In conclusion, Embelin did not influence the reproductive parameters assessed, confirming that it is not possible to predict whether the beneficial effect exerted by an antioxidant in a particular tissue could be present also in another one.

Tumour inhibition by interleukin-2 at the tumour/host interface.

Until recently, lymphokines were regarded suspiciously as 'ill-defined factors'. Today, however, some of them have been clearly defined in both structural and functional terms. The interleukin-2 (IL-2) molecule and its specific membrane receptors have been the subject of particular attention. Endogenous IL-2 has proved to be an important signal for the activation and expansion of various cell-mediated immunity functions, while exogenous IL-2 has been used to activate numerous cell functions, both in vitro and in vivo, as well as in tumour immunotherapy, both alone or combined with lymphocytes previously activated in vitro (lymphokine-activated killer cells). Adoptive transfer of these cells together with high doses of IL-2 is particularly promising from the clinical standpoint, though by no means free from problems. IL-2 can also be employed in small doses locally in the presence of non-activated lymphocytes from tumour bearing mice to induce a local reaction that subsequently becomes systemic and can lead to the rejection of incipient tumours. Various host immune cells, primarily eosinophils and lymphocytes are involved in this reaction, which can also give rise to tumour-specific immune memory. In this way, the host immune system, despite its inevitable defeat in the first battle against a tumour, may acquire an important role in the long war that lies ahead.

Cardiotoxicity of high-dose continuous infusion fluorouracil: a prospective clinical study.

PURPOSE: A prospective clinical study was performed to determine the incidence of high-dose continuous intravenous infusion fluorouracil (5FU-CIV) cardiotoxicity. PATIENTS AND METHODS: Three hundred sixty-seven patients who were given first-cycle high-dose 5FU-CIV were monitored for cardiac function by clinical examination, ECG, and laboratory tests. 5FU-CIV was administered during a 96- or 120-hour period at doses that ranged from 600 to 1,000 mg/m2/d. Associated drugs included cisplatin (56%), mitomycin (12.5%), folinic acid (leucovorin) (7%), and others (14%). Thirty-nine patients (10.5%) received 5FU as a single agent. RESULTS: 5FU-induced cardiac events occurred in 28 patients (7.6%; 95% confidence interval, 4.9% to 10.3%). Nine of them had a history of cardiac disease. Primary tumors included head and neck (n = 13), gastrointestinal (n = 6), breast (n = 3), and others (n = 6). The mean onset time of cardiac symptoms was 3 days (range, 2 to 5). Inaugural symptoms included angina pectoris (n = 18), hypotension (n = 6), hypertension (n = 5), malaise (n = 4), dyspnea (n = 2), arrhythmia (n = 1), or sudden death (n = 1). At 5FU discontinuation, six patients' cardiac symptoms returned to baseline, but 21 patients experienced unstable angina (n = 8), hypotension/cardiovascular collapse (n = 11), pulmonary edema (n = 1), or sudden death (n = 4). The lethality rate was 2.2% (five sudden deaths plus three irreversible collapses). ECG showed repolarization changes (ST segment deviation; T-wave inversion) in 65% and/or diffuse microvoltage in 22% of the patients who presented with cardiac events. Echocardiography showed partial or global hypokinesia in nine of the 16 patients who were examined, and one case of prolonged akinesia. Cardiac enzymes rarely showed an increase (n = 2). In severe but reversible cases, clinical, ECG, and echographic parameters returned to baseline status within 48 hours after the drug discontinuation. A fluorine 19 nuclear magnetic resonance (19F NMR) analysis of urine was performed on 14 patients; six had cardiac symptoms and eight did not. Fluoroacetate (FAC), a known cardiotoxic compound, was detected in all cases. CONCLUSION: In our study, the incidence of high-dose 5FU-CVI cardiotoxicity was 7.6%. The hypothesis of a toxic cardiomyopathic process requires further confirmation.

Etoposide bioavailability after oral administration of the prodrug etoposide phosphate in cancer patients during a phase I study.

PURPOSE: The purpose of this study was to determine the bioavailability (F) of etoposide (E;VP-16) after oral administration of the water-soluble prodrug etoposide phosphate (EP;BMY-40481) during a phase I trial in cancer patients. PATIENTS AND METHODS: Twenty-nine patients received oral EP (capsules, 50 to 150 mg/m2/d of E equivalent) for 5 days in week 1 (course 1), followed every 3 weeks thereafter by a daily intravenous (i.v.) infusion for 5 days of E (80 mg/m2, 1-hour i.v. infusion; course 2); in three patients, the i.v. E course was given before oral EP. Plasma and urine E pharmacokinetics (high-performance liquid chromatography [HPLC]) were performed on the first day of oral EP administration and on the first day of i.v. E. RESULTS: Twenty-six of 29 patients completed two courses or more, whereas three patients received only one course due to toxicity. Myelosuppression was dose-dependent and dose-limiting, with grade 4 leukoneutropenia in four of 15 patients at 125 mg/m2 and in five of seven patients at 150 mg/m2. One patient died of meningeal hemorrhage related to grade 4 thrombocytopenia. Other toxicities were infrequent and/or manageable. No objective response was observed. The maximum-tolerated dose (MTD) is therefore 150 mg/m2, and the recommended oral dose of EP for phase II trials in this poor-risk patient population is 125 mg/m2. Twenty-six patients had pharmacokinetic data for both oral EP and i.v. E, whereas three had pharmacokinetic data on the i.v. E course only. After oral administration of EP, the pharmacokinetics of E were as follows: mean absorption rate constant (Ka), 1.7 +/- 1.7 h-1 (mean +/- SD); lag time, 0.3 +/- 0.2 hours; time of maximum concentration (t(max)), 1.6 +/- 0.8 hours; and mean half-lives (t1/2), 1.6 +/- 0.2 (first) and 10.3 +/- 5.8 hours (terminal); the increase in the area under the plasma concentration-versus-time curve (AUC) of E was proportional to the EP dose. After the 1-hour i.v. infusion of E, maximum concentration (C(max)) was 15 +/- 3 micrograms/mL; mean AUC, 88.0 +/- 22.0 micrograms.h/mL; mean total-body clearance (CL), 0.97 +/- 0.24 L/h/m2 (16.2 mL/min/m2); and mean t1/2, 0.9 +/- 0.6 (first) and 8.1 +/- 4.1 hours (terminal). The 24-hour urinary excretion of E after i.v. E was significantly higher (33%) compared with that of oral EP (17%) (P < .001). Significant correlation was observed between the neutropenia at nadir and the AUC of E after oral EP administration (r = .58, P < .01, sigmoid maximum effect [E(max)] model). The mean F of E after oral administration of EP in 26 patients was 68.0 +/- 17.9% (coefficient of variation [CV], 26.3%; F range, 35.5% to 111.8%). In this study, tumor type, as well as EP dose, did not significantly influence the F in E. There was no difference in F of E, whether oral EP was administered before or after i.v. E. Compared with literature data on oral E, the percent F in E after oral prodrug EP administration was 19% higher at either low ( < or = 100 mg/m2) or high ( > 100 mg/m2) doses. CONCLUSION: Similarly to E, the main toxicity of the prodrug EP is dose-dependent leukoneutropenia, which is dose-limiting at the oral MTD of 150 mg/m2/d for 5 days. The recommended oral dose of EP is 125 mg/m2/d for 5 days every 3 weeks in poor-risk patients. Compared with literature data, oral EP has a 19% higher F value compared with oral E either at low or high doses. This higher F in E from oral prodrug EP appears to be a pharmacologic advantage that could be of potential pharmacodynamic importance for this drug.

Intensive concomitant chemoradiotherapy in locally advanced unresectable squamous cell carcinoma of the head and neck: a phase II study of radiotherapy with cisplatin and 7-week continuous infusional fluorouracil.

PURPOSE: To evaluate an intensive concomitant chemoradiotherapy protocol of conventional radiotherapy with intermittent cisplatin (CDDP) and continuous-infusion fluorouracil (5-FU) in unresectable, locally advanced squamous cell carcinoma of the head and neck (SCCHN). PATIENTS AND METHODS: Fifty-seven patients with unresectable stage IV MO disease (International Union Against Cancer [UICC]/American Joint Committee on Cancer [AJCC], 1987) received radiotherapy 70 Gy followed by CDDP 80 mg/m2 and 5-FU 300 mg/m2/d. Response was assessed 2 months after treatment completion. RESULTS: Thirty patients (52%) received the full treatment schedule; 53 (93%) received full-dose radiotherapy, while 48 (84%) were given at least 75% of the planned chemotherapy doses. Severe mucositis (World Health Organization [WHO]) grade 3 to 4 was the limiting toxicity and was seen in 79% of patients. The median time for mucositis resolution was 8 weeks. Other toxicities were generally manageable, but there were four treatment related deaths (7%). Fifty patients were assessable for activity, with an overall response rate of 70% (95% confidence interval [CI], 58% to 82%). Complete response (CR) and partial response (PR) rates were 42% and 28%, respectively. CONCLUSION: This simultaneous combined-modality regimen was feasible at the cost of severe mucosal toxicity, which required hospitalization with nutritional, parenteral, and hydroelectrolytic support. The high response rate achieved (70%) did not translate into improved survival, probably due to patient eligibility. The likelihood of cure of this high-tumoral-volume patient population remains low (approximately 10%), despite the association of two therapeutic modalities at full standard therapeutic intensity.