A novel antibiotic class targeting the lipopolysaccharide transporter

Carbapenem-resistant Acinetobacter baumannii (CRAB) has emerged as a major global pathogen with limited treatment options1. No new antibiotic chemical class with activity against A. baumannii has reached patients in over 50 years1. Here we report the identification and optimization of tethered macrocyclic peptide (MCP) antibiotics with potent antibacterial activity against CRAB. The mechanism of action of this molecule class involves blocking the transport of bacterial lipopolysaccharide from the inner membrane to its destination on the outer membrane, through inhibition of the LptB2FGC complex. A clinical candidate derived from the MCP class, zosurabalpin (RG6006), effectively treats highly drug-resistant contemporary isolates of CRAB both in vitro and in mouse models of infection, overcoming existing antibiotic resistance mechanisms. This chemical class represents a promising treatment paradigm for patients with invasive infections due to CRAB, for whom current treatment options are inadequate, and additionally identifies LptB2FGC as a tractable target for antimicrobial drug development.

Targeting virulence regulation to disarm Acinetobacter baumannii pathogenesis

The development of anti-virulence drug therapy against Acinetobacter baumannii infections would provide an alternative to traditional antibacterial therapy that are increasingly failing. Here, we demonstrate that the OmpR transcriptional regulator plays a pivotal role in the pathogenesis of diverse A. baumannii clinical strains in multiple murine and G. mellonella invertebrate infection models. We identified OmpR-regulated genes using RNA sequencing and further validated two genes whose expression can be used as robust biomarker to quantify OmpR inhibition in A. baumannii. Moreover, the determination of the structure of the OmpR DNA binding domain of A. baumannii and the development of in vitro protein-DNA binding assays enabled the identification of an OmpR small molecule inhibitor. We conclude that OmpR is a valid and unexplored target to fight A. baumannii infections and we believe that the described platform combining in silico methods, in vitro OmpR inhibitory assays and in vivo G. mellonella surrogate infection model will facilitate future drug discovery programs.

Tackling recalcitrant Pseudomonas aeruginosa infections in critical illness via anti-virulence monotherapy

Intestinal barrier derangement allows intestinal bacteria and their products to translocate to the systemic circulation. Pseudomonas aeruginosa (PA) superimposed infection in critically ill patients increases gut permeability and leads to gut-driven sepsis. PA infections are challenging due to multi-drug resistance (MDR), biofilms, and/or antibiotic tolerance. Inhibition of the quorum-sensing transcriptional regulator MvfR(PqsR) is a desirable anti-PA anti-virulence strategy as MvfR controls multiple acute and chronic virulence functions. Here we show that MvfR promotes intestinal permeability and report potent anti-MvfR compounds, the N-Aryl Malonamides (NAMs), resulting from extensive structure-activity-relationship studies and thorough assessment of the inhibition of MvfR-controlled virulence functions. This class of anti-virulence non-native ligand-based agents has a half-maximal inhibitory concentration in the nanomolar range and strong target engagement. Using a NAM lead in monotherapy protects murine intestinal barrier function, abolishes MvfR-regulated small molecules, ameliorates bacterial dissemination, and lowers inflammatory cytokines. This study demonstrates the importance of MvfR in PA-driven intestinal permeability. It underscores the utility of anti-MvfR agents in maintaining gut mucosal integrity, which should be part of any successful strategy to prevent/treat PA infections and associated gut-derived sepsis in critical illness settings. NAMs provide for the development of crucial preventive/therapeutic monotherapy options against untreatable MDR PA infections.

Pseudomonas aeruginosa infections are increasingly difficult to treat due to the development of antimicrobial resistance. Here, the authors describe the synthesis, characterisation and efficacy of a quorum sensing inhibitor.

A Niclosamide-releasing hot-melt extruded catheter prevents Staphylococcus aureus experimental biomaterial-associated infection

Biomaterial-associated infections are a major healthcare challenge as they are responsible for high disease burden in critically ill patients. In this study, we have developed drug-eluting antibacterial catheters to prevent catheter-related infections. Niclosamide (NIC), originally an antiparasitic drug, was incorporated into the polymeric matrix of thermoplastic polyurethane (TPU) via solvent casting, and catheters were fabricated using hot-melt extrusion technology. The mechanical and physicochemical properties of TPU polymers loaded with NIC were studied. NIC was released in a sustained manner from the catheters and exhibited in vitro antibacterial activity against Staphylococcus aureus and Staphylococcus epidermidis. Moreover, the antibacterial efficacy of NIC-loaded catheters was validated in an in vivo biomaterial-associated infection model using a methicillin-susceptible and methicillin-resistant strain of S. aureus. The released NIC from the produced catheters reduced bacterial colonization of the catheter as well as of the surrounding tissue. In summary, the NIC-releasing hot-melt extruded catheters prevented implant colonization and reduced the bacterial colonization of peri-catheter tissue by methicillin sensitive as well as resistant S. aureus in a biomaterial-associated infection mouse model and has good prospects for preclinical development.

Mouse pneumonia model by Acinetobacter baumannii multidrug resistant strains: Comparison between intranasal inoculation, intratracheal instillation and oropharyngeal aspiration techniques

Infectious pneumonia induced by multidrug resistant (MDR) Acinetobacter baumannii strains is among the most common and deadly forms of healthcare acquired infections. Over the years, different strategies have been put in place to increase host susceptibility to MDR A. baumannii, since only a self-limiting pneumonia with no or limited local bacterial replication was frequently obtained in mouse models. Direct instillation into the trachea or intranasal inoculation of the bacterial suspension are the techniques used to induce the infection in most of the preclinical models of pneumonia developed to date. More recently, the oropharyngeal aspiration procedure has been widely described in the literature for a variety of purposes including pathogens administration. Aim of this study was to compare the oropharyngeal aspiration technique to the intranasal inoculation and intratracheal instillation in the ability of inducing a consistent lung infection with two MDR A. baumannii clinical isolates in immunocompromised mice. Moreover, pneumonia obtained by bacteria administration with two out of three techniques, intratracheal and oropharyngeal, was characterised in terms of histopathology of pulmonary lesions, biomarkers of inflammation level and leukocytes cells infiltration extent after mice treatment with either vehicle or the antibiotic tigecycline. The data generated clearly showed that both strains were not able to colonize the lungs when inoculated by intranasal route. By contrast, the bacterial load in lungs of mice intratracheally or oropharyngeally infected significantly increased during 26 hours of monitoring, thus highlighting the ability of these strains to generate the infection when directly instilled into the lower respiratory airways. Furthermore, the intragroup variability of mice was significantly reduced with respect to those intranasally administered. Tigecycline was efficacious in lung bacterial load and cytokines release reduction. Findings were supported by semi-quantitative histopathological evaluation of the pulmonary lesions and by inflammatory biomarkers analysis. To conclude, both intratracheal instillation and oropharyngeal aspiration techniques showed to be suitable methods for inducing a robust and consistent pneumonia infection in mice when difficult MDR A. baumannii clinical isolates were used. Noteworthy, oropharyngeal aspiration not requiring specific technical skills and dedicated equipment, was proven to be a safer, easier and faster technique in comparison to the intratracheal instillation.

Heat load increases the risk of clinical mastitis in dairy cattle

The study was aimed at assessing heat load-related risk of clinical mastitis (CM) in dairy cows. Records of CM for the years 2014 and 2015 were obtained from a large conventional dairy farm milking about 1,200 Holstein cows in central Italy. A case of CM was defined by the presence of clinical signs and veterinary confirmation. Quarter milk samples were collected and bacteriological investigated for each CM. Etiological agents were identified and classified as environmental or contagious pathogens. Hourly weather data from the nearest weather station were used to calculate heat load index (HLI). Upper and lower thresholds of HLI, at which the animal accumulates or dissipates heat, were settled and used to measure heat load balance through the accumulated heat load (AHL) model. Zero and positive values of AHL indicate periods of thermo-neutral and heat accumulation, respectively. Each case of CM was associated with HLI-AHL values recorded 5 d before the event. The risk of CM was evaluated using a case-crossover design. A conditional logistic regression model was used to calculate the odds ratio and 95% confidence intervals of CM recorded in thermo-neutral (AHL = 0) or heat load (AHL > 0) days, pooled or stratified for pathogen type (environmental or contagious). Classes of AHL as low (<6.5), medium (6.6-34.9), and high (>35) were included in the model. Other variables included in the model were milk yield as liters (<20, 20-30, and >30), days in milk (<60, 60-150, and >150), and parity (1, 2-3, and >3). A total of 1,086 CM cases were identified from 677 cows. Escherichia coli, Streptococcus spp., and Streptococcus uberis were the environmental pathogens isolated with the highest frequency; Staphylococcus aureus prevailed within contagious species. The analysis of pooled data indicated a significant effect of heat load on the occurrence of CM in the contagious pathogen stratum. Higher milk yield, middle and late stage of lactation, and older parity increased the risk of CM under heat load conditions. However, the association between pathogen type and these factors was not clear because the model provided significant odds ratios within all pathogen categories. The present study provided the first evidence of an association between HLI and CM in dairy cattle and suggested the ability of the AHL model to assess the risk of mastitis associated with heat load.

Sentinel Lymphadenectomy in Cutaneous Melanoma

Aims and Background

In the last ten years validation of the sentinel lymph node (SLN) concept has led to modification of the surgical approach for patients with intermediate-risk cutaneous melanoma.

Methods and Study Design

Forty-eight patients affected by cutaneous melanoma with a Breslow thickness between 0.65 and 4 mm were enrolled in the study. Approximately 2 mCi of radiotracer and 1 mL of vital blue dye were injected in each patient around the site of the primary lesion. Lymphoscintigraphy was performed until the lymphatic basin and the respective SLN were localized. The whole surgical procedure consisted of enlargement of the surgical margins followed by localization and excision of the SLN(s) by using both radiotracer and vital dye. Whenever the SLN proved to be histologically positive for metastasis, complete regional lymphadenectomy was performed.

Results

Within 15 minutes of radiotracer administration the lymphatic basin was localized in all 48 patients by lymphoscintigraphy. Vital dye and radiotracer successfully allowed SLN localization and excision in 46 of 48 patients (97%); in one case the SLN was detected by radiotracer alone. The SLN proved to be metastatic in six (13%) of 46 evaluable patients; interestingly, in three of them the presence of metastatic cells was revealed only by immunohistochemistry. All patients with tumor-positive SLNs had primary lesions with a Breslow thickness = 2 mm.

Conclusions

Sentinel lymphadenectomy is able to identify lymph node involvement in patients with cutaneous melanoma with a Breslow thickness >1 mm, thus avoiding the risks associated with radical regional lymphadenectomy. Lymphoscintigraphy proved to be an important tool to obtain correct preoperative localization of the drainage basin, especially for melanomas located on the face and trunk.

Minimal Sentinel Node Procedure for Staging Early Breast Cancer

Aims and Background

Sentinel lymph node dissection (SLND) has recently been evaluated as a new staging technique for early breast cancer. To minimize the extent of surgery, the feasibility of eradicating primary breast lesions and the relative sentinel lymph nodes (SLN) under regional anesthesia was evaluated in this study.

Methods and Study Design

A selected population of 76 patients with suspected operable breast cancer and no clinically palpable lymph nodes was enrolled in the study. Intra- and perilesional administration of a radiotracer was performed. Lymphoscintigraphy was carried out to confirm the drainage pathway and locate the SLN. The following day, after inducing a nervous block induction of the ipsilateral intercostal nerves, we performed the surgical procedure with the help of a hand-held gamma-detecting probe. In case the primary lesion was diagnosed as invasive carcinoma by frozen section, the SLN and the remaining axillary lymph nodes (non-SLNs) were removed. The status of SLN and non-SLNs was compared.

Results

The primary breast lesion was located and excised in all cases (identification rate: 100%). Lymphoscintigraphy positively identified SLNs in 40/45 (89%) patients; in five patients no lymphatic drainage was detected. In 38 cases an average of 1.5 SLNs and 14 non-SLNs per patient were removed and pathologically analyzed; the remaining two patients showed SLNs in the internal mammary chain, which were not excised. Twenty-nine percent of the patients showed metastatic disease in the lymph nodes examined. Of all patients with affected nodes, 55% had cancer cells only in the SLN. No false negatives (skip metastases) were found. No immediate or long-term anesthesia-related complications (eg pleural lesions, intravascular injection) were observed.

Conclusions

Our data confirm the feasibility of single radiotracer administration for both occult lesion and SLN localization as well as the usefulness of SLND in staging early breast cancer. Regional anesthesia resulted in easy management and good patient compliance. This time-saving procedure allowed the completion of the whole surgical plan, reducing the recovery time without modifying the effectiveness of surgery.

Survival of Mycobacterium avium subsp. paratuberculosis in the intermediate and final digestion products of biogas plants

AIMS

To evaluate the survival of Mycobacterium avium subsp. paratuberculosis (MAP) during anaerobic digestion (AD), we studied two different biogas plants loaded with manure and slurry from paratuberculosis-infected dairy herds.

METHODS AND RESULTS

Both plants were operating under mesophilic conditions, the first with a single digester and the second with a double digester. Mycobacterium avium subsp. paratuberculosis detection was performed by sampling each stage of the process, specifically the prefermenter, fermenter, liquid digestate and solid digestate stages, for 11 months. In both plants, MAP was isolated from the prefermenter stage. Only the final products, the solid and liquid digestates, of the one-stage plant showed viable MAP, while no viable MAP was detected in the digestates of the two-stage plant.

CONCLUSIONS

Mycobacterium avium subsp. paratuberculosis showed a significant decrease during subsequent steps of the AD process, particularly in the two-stage plant. We suggest that the second digester maintained the digestate under anaerobic conditions for a longer period of time, thus reducing MAP survival and MAP load under the culture detection limit.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our data are unable to exclude the presence of MAP in the final products of the biogas plants, particularly those products from the single digester; therefore, the use of digestates as fertilizers is a real concern related to the possible environmental contamination with MAP.

Polypharmacology Approaches against the Pseudomonas aeruginosa MvfR Regulon and Their Application in Blocking Virulence and Antibiotic Tolerance

Pseudomonas aeruginosa is an important nosocomial pathogen that is frequently recalcitrant to available antibiotics, underlining the urgent need for alternative therapeutic options against this pathogen. Targeting virulence functions is a promising alternative strategy as it is expected to generate less-selective resistance to treatment compared to antibiotics. Capitalizing on our nonligand-based benzamide-benzimidazole (BB) core structure compounds reported to efficiently block the activity of the P. aeruginosa multiple virulence factor regulator MvfR, here we report the first class of inhibitors shown to interfere with PqsBC enzyme activity, responsible for the synthesis of the MvfR activating ligands HHQ and PQS, and the first to target simultaneously MvfR and PqsBC activity. The use of these compounds reveals that inhibiting PqsBC is sufficient to block P. aeruginosa's acute virulence functions, as the synthesis of MvfR ligands is inhibited. Our results show that MvfR remains the best target of this QS pathway, as we show that antagonists of this target block both acute and persistence-related functions. The structural properties of the compounds reported in this study provide several insights that are instrumental for the design of improved MvfR regulon inhibitors against both acute and persistent P. aeruginosa infections. Moreover, the data presented offer the possibility of a polypharmacology approach of simultaneous silencing two targets in the same pathway. Such a combined antivirulence strategy holds promise in increasing therapeutic efficacy and providing alternatives in the event of a single target's resistance development.

The opioid receptor pharmacology of GSK1521498 compared to other ligands with differential effects on compulsive reward-related behaviours

RATIONALE

The novel opioid receptor antagonist, GSK1421498, has been shown to attenuate reward-driven compulsive behaviours, such as stimulant drug seeking or binge eating, in animals and humans. Here, we report new data on the receptor pharmacology of GSK121498, in comparison to naltrexone, naloxone, 6-β-naltrexol and nalmefene.

OBJECTIVES

To determine whether the novel opioid antagonist, GSK1521498, is an orthosteric or allosteric antagonist at the μ opioid receptor (MOPr) and whether it has neutral antagonist or inverse agonist properties.

METHODS

A combination of radioligand binding assays and [(35)S]GTPγS binding assays was employed.

RESULTS

GSK1521498 completely displaced [(3)H]naloxone binding to MOPr and did not alter the rate of [(3)H]naloxone dissociation from MOPr observations compatible with it binding to the orthosteric site on MOPr. GSK1521498 exhibited inverse agonism when MOPr was overexpressed but not when the level of MOPr expression was low. In parallel studies under conditions of high receptor expression density, naloxone, naltrexone, 6-β-naltrexol and nalmefene exhibited partial agonism, not inverse agonism as has been reported previously for naloxone and naltrexone. In brain tissue from mice receiving a prolonged morphine pre-treatment, GSK1521498 exhibited slight inverse agonism.

CONCLUSIONS

Differences between GSK1521498 and naltrexone in their effects on compulsive reward seeking are arguably linked to the more selective and complete MOPr antagonism of GSK1521498 versus the partial MOPr agonism of naltrexone. GSK1521498 is also pharmacologically differentiated by its inverse agonist efficacy at high levels of MOPr expression, but this may be less likely to contribute to behavioural differentiation at patho-physiological levels of expression.

Targeting cystalysin, a virulence factor of treponema denticola-supported periodontitis

Cystalysin from Treponema denticola is a pyridoxal 5'-phosphate dependent lyase that catalyzes the formation of pyruvate, ammonia, and sulfide from cysteine. It is a virulence factor in adult periodontitis because its reaction contributes to hemolysis, which sustains the pathogen. Therefore, it was proposed as a potential antimicrobial target. To identify specific inhibitors by structure-based in silico methods, we first validated the crystal structure of cystalysin as a reliable starting point for the design of ligands. By using single-crystal absorption microspectrophotometry, we found that the enzyme in the crystalline state, with respect to that in solution, exhibits: 1) the same absorption spectra for the catalytic intermediates, 2) a close pKa value for the residue controlling the keto enamine ionization, and 3) similar reactivity with glycine, L-serine, L-methionine, and the nonspecific irreversible inhibitor aminoethoxyvinylglycine. Next, we screened in silico a library of 9357 compounds with the Fingerprints for Ligands and Proteins (FLAP) software, by using the three-dimensional structure of cystalysin as a template. From the library, 17 compounds were selected and experimentally evaluated by enzyme assays and spectroscopic methods. Two compounds were found to competitively inhibit recombinant T. denticola cystalysin, with inhibition constant (Ki ) values of 25 and 37 μM. One of them exhibited a minimum inhibitory concentration (MIC) value of 64 μg mL(-1) on Moraxella catarrhalis ATCC 23246, which proves its ability to cross bacterial membranes.

Adjuvant chemotherapy with cisplatin and gemcitabine versus chemotherapy at relapse in patients with muscle-invasive bladder cancer submitted to radical cystectomy: an Italian, multicenter, randomized phase III trial

BACKGROUND

The purpose of the study was to evaluate the benefit of adjuvant chemotherapy (AC) versus surgery alone in patients with muscle-invasive bladder cancer (MIBC).

PATIENTS AND METHODS

One hundred and ninety-four patients with pT2G3, pT3-4, N0-2 transitional cell bladder carcinoma were randomly allocated to control (92 patients) or to four courses of AC (102 patients). These latter patients were further randomly assigned to receive gemcitabine 1000 mg/m(2) days 1, 8 and 15 and cisplatin 70 mg/m(2) day 2 or gemcitabine as above plus cisplatin 70 mg/m(2) day 15, every 28 days.

RESULTS

At a median follow-up of 35 months, the 5-year overall survival (OS) was 48.5%, with no difference between the two arms [P = 0.24, hazard ratio (HR) 1.29, 95% confidence interval (CI) 0.84-1.99]. Mortality hazard was significantly correlated with Nodes (N) and Tumor (T) stage. The control and AC arms had comparable disease-free survival (42.3% and 37.2%, respectively; P = 0.70, HR 1.08, 95% CI 0.73-1.59). Only 62% of patients received the planned cycles. A significant higher incidence of thrombocytopenia was observed in patients receiving cisplatin on day 2 (P = 0.006). A similar global quality of life was observed in the two arms.

CONCLUSION

The study was underpowered to demonstrate that AC with cisplatin and gemcitabine improves OS and disease-free survival in patients with MIBC.

A changing landscape in castration-resistant prostate cancer treatment

Prostate cancer (PC) is the leading cause of cancer and the second leading cause of cancer-death among men in the Western world. About 10-20% of men with PC present with metastatic disease at diagnosis, while 20-30% of patients diagnosed with localized disease will eventually develop metastases. Although most respond to initial androgen-deprivation therapy (ADT), progression to castration-resistant PC (CRPC) is universal. In 2004 the docetaxel/prednisone regimen was approved for the management of patients with metastatic CRPC, becoming the standard first-line therapy. Recent advances have now led to an unprecedented number of new drug approvals within the past years, providing many new treatment options for patients with metastatic CRPC. Four new drugs have received U.S. Food and Drug Administration (FDA)-approval in 2010 and 2011: sipuleucel-T, an immunotherapeutic agent; cabazitaxel, a novel microtubule inhibitor; abiraterone acetate, a new androgen biosynthesis inhibitor; and denosumab, a bone-targeting agent. The data supporting the approval of each of these agents are described in this review, as are current approaches in the treatment of metastatic CRPC and ongoing clinical trials of novel treatments and strategies.

Dramatic Regression of Multiple Brain Metastases from Breast Cancer with Capecitabine: Another Arrow at the Bow?

Several chemotherapic agents, which are active against breast cancer, penetrate poorly into the central nervous system. Despite its limited brain penetration, 5-fluorouracil has been a component of effective regimens for brain metastases. Capecitabine is a recently developed oral prodrug that is converted into 5-fluorouracil by sequential enzymatic steps. Thymidine phosphorylase (TP) is the final enzyme responsible for Capecitabine activation. Studies have demonstrated that high intratumoral levels of TP and low levels of its catabolite dihydropyrimidine-dehydrogenase are correlated with the capecitabine response. The penetration of Capecitabine across the brain-blood barrier remains unknown; we report the case of and discuss a breast cancer patient who had an interesting response of brain metastases with Capecitabine in monochemotherapy before brain irradiation.

Dose-escalating study of continuative low dose of oral vinorelbine in patients with advanced breast cancer

1128

Background: Low and continuative dose of antineoplastic drugs has been shown to have an antiangiogenic activity. The rapid absorption and relatively short half-life of the oral formulation of vinorelbine are favorable pharmacokinetic characteristics to test a continuative low-dose schedule. Methods: Patients with measurable metastatic breast cancer were treated with escalating dose of oral vinorelbine from 50 mg/m2 per week to 90 mg/m2 per week until progressive disease or unacceptable toxicity. These patients were administered one third of the total weekly dose 3 times per week, every other day. A pharmacokinetic analysis was planned at the first 3 weeks of drug assumption. Results: Of twenty-two patients included in the study, 3 were treated at 50 mg/m2/w (level 1), 5 at 60 mg/m2/w (level 2), 3 at 70 mg/m2/w (level 3), 8 at 80 mg/m2/w (level 4), and 3 at 90 mg/m2/w (level 5); we are still enrolling patients at this level. The median age was 59 years (range 23–75). The median number of prior lines of chemotherapy and hormonal therapy was 2 (range 0–4 for CT and 0–5 for OT). Fifteen of 22 patients had visceral metastasis. No dose-limiting toxicities have been observed until now. The main toxicities were: asymptomatic neutropenia grade 4 in two patients (1 in level 4 and 1 in level 5), asthenia grade 3 in 7 patients (1 at level 1, 2 at level 2, 1 at level 3, 3 at level 4), neurotoxicity grade 3 in two patients (one at level 2 and one at level 4). One patient experienced an intestinal sub-occlusion and hospitalization was required with no permanent side effects. One patient had a partial response, five a stable disease, fourteen progressed and two are not evaluated yet. At 1 year, five of the twenty evaluable patients are died by disease. Samples of twenty patients were collected for pharmacokinetic analysis that will be presented at the meeting. Conclusions: The continuative split 3 times per week oral vinorelbine is feasible, and at 90 mg/m2/w we have not reached yet the maximum tolerated dose.

No significant financial relationships to disclose.

Gene expression as a predictive marker of outcome for high-risk transitional-cell carcinoma (TCC) of the bladder in patients (pts) randomized to adjuvant chemotherapy with cisplatin-gemcitabine (PG) or observation (OBS) after radical cystectomy

15502

Background: A randomized phase III trial comparing PG vs OBS in muscle-invasive TTC of the bladder is currently ongoing. ERCC1 and RRM1 genes are involved in the nucleotide excision repair pathways, and their up-regulation by tumor has been clearly related to resistance of cisplatin and gemcitabine, respectively. Preliminary correlations in patients with bladder cancer randomized to PG were already presented (Proc ASCO 2005, Abstract No: 4589). In the present study, we have examined the predictive value of ERCC1 and RRM1 as markers of tumor progression, as well as their potential correlation with other known prognostic factors also in patients randomized to OBS. Methods: Thirty-nine paraffin-embedded TTC samples of a subset of patients entered the trial were collected. The characteristics were: pT2 23%, pT3 54%, pT4a 23%, pN1–2 46%; G3–4 98%; M/F 10%/90%, median age: 65 years (range 53–74); PG/OBS: 49%/51%. Analysis consisted of real time RT-PCR quantification of mRNA levels of ERCC1 and RRM1. Results: After a median follow-up of 25 months (range 12–51), 17 patients relapsed and 10 deceased. A good correlation was found between mRNA expression levels of both genes. Three-year disease-free survival (DFS) was 74% vs 33% for patients with low and high ERCC1 expression (p=0.03), and 64% vs 22% for those with low and high RRM1 expression (p=0.26), respectively. Comparable result in favour of patients showing lower ERCC1 mRNA levels was found in both groups of patients randomized to PG or obs. Multivariate analysis demonstrated that only the presence of N1–2 and low expression level of ERCC1 were significant prognostic factor for better DFS (HR 4.358, 2.775 and p value = 0.006 and 0.046, respectively). Conclusions: Determination of ERCC1 mRNA expression level in muscle-invasive bladder cancer can make a contribution as an independent predictor of DFS after radical cystectomy. It’s still unclear if quantification of ERCC1 gene expression level could interact with adjuvant chemotherapy. Longer follow-up will help to address this issue (Supported by CNR-MIUR grants 02.00447, 03.00387-ST97).

No significant financial relationships to disclose.

Fixed dose rate (FDR) gemcitabine as radiosensitizer for newly diagnosed glioblastoma multiforme (GBM): Preliminary results of a phase II study

12502

Background: In a previous phase I study (ASCO 2006), where FDR Gemcitabine at 10/mg/m2/min was tested in association with radiotherapy (RT) for the treatment of newly diagnosed GBM, a maximum tolerated dose of 175 mg/m2/wk was identified. Methods: After surgery for GBM (either citoreduction or sterebiopsy), patients were treated with fractionated focal RT at a daily dose of 2.0 Gy per fraction, five days per week for six weeks (total dose of 60 Gy). FDR Gemcitabine at 175 mg/m2/wk was given concomitantly starting 24–72 hours prior to RT and then for the whole duration of RT. An MRI performed at 7 and 40 days from the end of chemo-radiotherapy was used for activity assessment. Standard oral temozolamide 150–200 mg/m2 was administrated following the combined treatment. Results: From 07/2004 16 patients (9 male, 7 female) have been enrolled. Characteristics of patients were: median age 57 years (42–72), median KPS at baseline 90 (70–100), surgery/stereobiopsy 14/2. Median time from diagnosis to initiation of Gemcitabine was 45 days (28–54). Among the 14 evaluable patients 3 (21.4%) partial responses, 7 (50%) stable disease and 4 (28.5%) progressive diseases were recorded. At a median follow up of 18 months (2–33) time to progression was 6 months (1.5–24). Toxicity was manageable with only one G3 neutropenia and hypertransaminasemia in two patients respectively. Grade 1 hypertransaminasemia was registered in 6 patients (43%). Conclusions: These preliminary results show that in patients with newly diagnosed GBM, radiosensitizing FDR Gemcitabine at 175 mg/m2/wk is a well tolerated regimen with an interesting activity. Accrual is ongoing and final results will be presented at the meeting.

No significant financial relationships to disclose.

Dose scheduling and pharmacokinetic (PK) study of trastuzumab in patients (pts) with HER2/neu overexpressing breast cancer?

1109

Has been demonstrated that 10–20 μg/mL is the minimum serum trough concentration (Cmin) of trastuzumab that causes maximal tumor growth inhibition. This concentration was shown to be achievable using a weekly (4 mg/kg loading dose followed by 2 mg/kg weekly) and a three-weekly (8 mg/kg loading dose followed by 6 mg/kg) schedule, but only indirect comparisons of the two schedule have been performed. We prospectively analysed the PK distribution of trastuzumab in three different schedules, as follows: weekly (cohort I), bi-weekly (trastuzumab 6 mg/kg loading dose followed by 4 mg/kg, cohort II) and three-weekly schedule (cohort III). The PK analysis was performed in 18 pts (4 pts receiving the loading dose of cohort III, 8 pts receiving the maintenance dose of cohort III, 3 pts receiving the maintenance dose of cohort II, and 3 pts receiving loading dose of cohort I). Of the 18 pts analyzed, 9 were metastatic. The median age was 54 years (range 39–76), the median weight was 61,5 kg (range 53–80). At diagnoses, 10 pts had stage I disease, 5 and 3 pts had stage II and III respectively, ER was negative in 10 pts and PgR was negative in 12 pts; Ki67 was highly expressed in 14 pts; Her/neu was overexpressed and amplified in 16 and 2 pts respectively. To evaluate preliminary interpatient variability, 3 pts receiving 6mg/kg of trastuzumab repeated the PK analysis after four cycles: the comparison between two groups was not statistically significative. Comparison of Cmax and AUC mean between groups was statistically significative (P<0.05, Bonferroni test) except for 8 mg/kg vs 6 mg/kg AUC.All the doses and schedules analysed are able to reach the minimum serum concentration of trastuzumab that causes the maximal tumor growth inhibition.

[Table: see text]

No significant financial relationships to disclose.

Pilot study of capecitabine combined with celecoxib (CapCel) for the treatment of far advanced metastatic breast cancer (MBC) patients (pts)

10680

Background: COX-2 is overexpressed during cancer progression in several solid tumors, including breast cancer, and constitutes an attractive therapeutic target. Selective COX-2 inhibitors, such as Celecoxib, have been successfully combined with fluoropyrimidine-based regimens, resulting in a lower-than-expected hematologic, GI, and skin toxicity rate. Methods: MBC pts who had progressed after at least one chemotherapy regimen for metastatic disease were eligible for the study. Capecitabine was administered at the starting dose of 1500–2000 mg/m2 daily for 14 days q3 wks. Celecoxib was administered at 200 mg b.i.d., continuously, starting on day 1. Dose escalation to Capecitabine 2000 or 2500 mg/m2 was allowed in the absence of toxicity > G1. Results: To date, 22 pts (median age: 55 yrs, range 35–81; ECOG PS 0: 21 pts) have been accrued; all pts had MBC and the majority had received adjuvant chemotherapy and hormonal treatment in the adjuvant and/or metastatic setting; all pts had been exposed to anthracyclines and/or taxanes. CapCel was administered as 2nd-, 3rd-, or ≥ 4th-line chemotherapy in 3, 10, and 9 pts, respectively. Capecitabine starting dose was 1500 mg/m2 in 9 pts and 2000 mg/m2 in 13 pts. Median number of cycles administered was 5 (range: 1–15). Toxicity was negligible: 1 pt experienced G3 neutropenia, 2 pts G3 skin/nail toxicity, and 1 pt G3 liver toxicity; all other toxicities were of grade ≤2. No Celecoxib-related GI or cardiovascular toxicities were observed. Capecitabine dose was escalated from 1500 to 2000 mg/m2 in 3/9 pts and from 2000 to 2500 mg/m2 in 2/13 pts, respectively, and reduced from 2000 to 1500 mg/m2 in 4/13 pts. Twenty pts are currently evaluable for response: 2 pts had PR (duration 48 and 49 wks, respectively), 15 pts had SD (median duration: 20 wks, range 12–44), and 3 pts progressed on therapy, for an overall clinical benefit rate of 40%. Median survival has not been reached. Conclusions: Overall, these preliminary results indicate that CapCel is extremely well-tolerated and has significant anti-tumor activity in a population of far advanced MBC pts. The study will continue to reach the projected accrual of 45 pts.

No significant financial relationships to disclose.

Incidence of brain metastases after first line chemotherapy in breast cancer patients treated with or without trastuzumab

10582

Background: Brain metastases during trastuzumab therapy have been frequently observed. Only a few studies have compared the risk of brain metastases in patients (pts) treated with or without trastuzumab. Methods: In our hospital, between Jun 2000 and September 2005, we conducted a retrospective study in 72 metastatic breast cancer pts treated with first-line mono-chemotherapy (CT) with paclitaxel or docetaxel or vinorelbine ± Trastuzumab (T). Results: Thirty-five pts with HER2 pos disease were treated with T associated with 1st line CT, while 37 pts (16 with HER2 positive tumor, 21 HER2 negative) were not treated with T (NT). Ten HER2 pos NT pts subsequently received T. The median follow-up was 21 months (range1–129); the median age was 54 (range 32–82); the median treatment duration was 5 months (range 1–29). The incidence of recurrence (R), progressive disease in brain (BR), progression free survival (PFS) after first line CT, and overall survival (OS) were reported below: (see Table) Conclusions: This study showed that, after first line chemotherapy, the use of T did not affect the incidence of BR in HER2 pos metastatic breast cancer pts. On the other hand, Her-2 neg seems to predict ‘per se‘ a lower incidence of cerebral spread of disease.

[Table: see text]

No significant financial relationships to disclose.

A pharmacokinetic study of gemcitabine at fixed dose rate infusion in patients with impaired hepatic function

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Background: The aim of this study was to evaluate if hepatic dysfunction leads to increased toxicity of gemcitabine (gem) at fixed dose rate, and to characterize the pharmacokinetic (PK) of gem and its major metabolite (2`,2`-difluorodeoxyuridine- 2dFdU) in patients (pts) with normal and altered liver function. Methods: Eight pts with metastatic pancreatic or biliary tract cancer were treated with the followed schedule: gem 1000 mg/m2 at 10/mg/m2/min fixed rate days 1,8, and 15 every 28 days for a maximum of six cycles. Three pts had normal serum bilirubin level and AST level less than two times the upper limit of normal (ULN) (Cohort I); four pts had bilirubin level from 1.6 to 7.0 mg/dL and normal AST level, one pt had serum bilirubin level less than 1.6 mg/dL and AST level greater than two times the ULN (Cohort II). The PK parameters measured were: plasmatic peak concentration (Cmax), area under the plasma concentration-time curve (AUCexp), total plasma clearance (Cl p) and half life (t1/2). Results: Patient characteristics were: median age 62 yrs (range 28–75), male/female 4/4, median cycles cohort I: 6 cycles (3–6), median cycles cohort II: 3 cycles (1–5), median follow-up: 30 weeks (range 3–79) and median weeks of treatment: 14 (1–25). The rate of dose reduction was the same in the two cohorts, as the rate of omitted administrations. Patients with liver dysfunction tolerated gemcitabine without increased toxicity and neither AST nor bilirubin elevation was observed after drug administration. PK parameters were calculated at the first cycle and the results are presented below (see table ). Conclusions: The pharmacokinetics of gemcitabine at fixed dose rate in patients with impaired liver function seems similar to control; no difference between the two cohorts was observed in terms of toxicity and dose reduction.

[Table: see text]

No significant financial relationships to disclose.

A new phalloplasty technique: the free anterolateral thigh flap phalloplasty

After a 10-year experience with phalloplasty in female to male gender reassignment surgery and with more than one hundred cases treated, we have introduced a new technique for creation of the neo-phallus. Between 1993 and 2002, phalloplasties were performed in our department using the free radial forearm flap or the pre-expanded suprapubic flap (modified Pryor technique). The study of long-term results and complications of these cases, as well as patient requests for a new donor site, induced us to look for an alternative flap for phalloplasty. The versatility and the low donor site morbidity of anterolateral thigh flap persuaded us to use it for phalloplasty. Since March 2003, six phalloplasties with free anterolateral thigh (ALT) flap have been performed. The results have been encouraging. The shape and the consistency of the neo-phallus are suitable, the flap can be sensate and an erectile prosthesis can easily be implanted. Penile urethral reconstruction is possible in the same operative stage. Patient satisfaction is high. The anatomy and harvesting techniques of ALT flap have already been exhaustively described by several authors and only the operative technique of phalloplasty with free ALT flap, donor site management, preliminary results and complications are reported in this paper.

Prolonged gemcitabine infusion as radiosensitizer for newly diagnosed glioblastoma multiforme (GBM): A phase I study

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Background: The use of cytotoxic drugs concurrent with RT represents a promising approach in the combined treatment of malignant gliomas. Gemcitabine (dFdCyd) is a drug widely explored for its potential radiomimetic activity in different tumors. The present study was aimed to evaluate the dose-limiting toxicity (DLT) and maximum tolerated dose (MTD) of weekly prolonged dFdCyd infusion, administered in combination with RT as first line treatment, in adult pts affected by supratentorial GBM. Methods: Within 6 weeks after surgery, in the presence of measurable residual disease and KPS >70, pts were treated with fractionated RT at a dose of 2.0 Gy/daily fractions, 5 days a week (global dose 60 Gy). From 24 to 72 hours before the first RT application, and afterwards once weekly, pts received concurrent dFdCyd, at fixed dose rate of 10 mg/m2/min, over a total period of six weeks. Planned dose levels of dFdCyd started from 200 mg/m2/weekly (level 1), with sequential steps of 25 mg/m2/w based on toxicity. Results: Ten pts were enrolled into the study: six were male, median age 55.2 years (range 44–75), with a median KPS at baseline of 85 (SD 9.71). The median time from diagnosis to the start of treatment was six weeks (range 4–7). The median RT duration was 6 weeks (range 4–7), all but one pt received the planned dose and all pts received concomitant CT. Four pts entered at Level 1; one pt was excluded from the study, due to rapid progressive disease during the treatment. Two of the three valuable pts presented a relevant neurological worsening; on this basis the dFdCyd dose was reduced to 175 mg/m2/w (Level -1). A total of six pts were entered at Level -1, and none of them reported DLT. No hematological grade 3–4 toxicity was reported. Grade 3 non-hematological toxicity was observed in one pt (transaminases increase). After a median follow-up of 13.4 months (range 3–24), the median progression-free survival was 8 months (CI 95% 1–18), and the median overall survival was 14 months (CI 95% 12–17). Conclusions: The recommended dose of prolonged infusion of dFdCyd concomitant with RT is 175 mg/m2/w. The observed activity has been considered interesting enough to support a phase II study of this concurrent CT-RT schedule as first line treatment in GBM.

[Table: see text]

Second- and third-generation aromatase inhibitors as first-line endocrine therapy in postmenopausal metastatic breast cancer patients: a pooled analysis of the randomised trials

The purpose of this study was to estimate in all randomised trials the relative risk of overall response rate (ORR), clinical benefit (CB), time to progression (TTP), overall survival (OS), and toxicity of aromatase inhibitors (AI), compared with tamoxifen (Tam) as first-line endocrine therapy in postmenopausal metastatic breast cancer (PMBC) women. Prospective randomised studies were searched through computerised queries of MEDLINE, EMBASE, and the American Society of Clinical Oncology (ASCO) abstract database. Relative risk, 95% confidence interval, and heterogeneity were derived according to the inverse variance and Mantel–Haenszel method and Q statistics. Six phase III prospective randomised trials including 2787 women were gathered. A significant advantage in ORR (P=0.042), TTP (P=0.007), and CB (P=0.001) in favour of AI over Tam was detected at the fixed effects model. These results were not significant at the random effects model, owing to the significant heterogeneity. On the contrary, no difference was registered for OS (P=0.743) with no significant heterogeneity. Regarding toxicity, Tam caused more frequently thromboembolic events (P=0.005) and vaginal bleeding (P=0.001) compared with AI. Aromatase inhibitors appear to be superior to Tam as first-line endocrine option in PMBC women. Owing to a component of variability between the six studies analysed, the random effects estimates differed from corresponding fixed ones. Investigators should assess heterogeneity of trial results before deriving summary estimates of treatment effect.

A pharmacokinetic interaction study of docetaxel and cisplatin plus or minus 5-fluorouracil in the treatment of patients with recurrent or metastatic solid tumors

BACKGROUND

The purpose of this study was to look at the pharmacokinetics of docetaxel, cisplatin-derived platinum and 5-fluorouracil (5-FU), when used in combination, to exclude potential clinically relevant pharmacokinetic interactions.

METHODS

Fifteen patients with recurrent or metastatic solid tumors were randomized to receive docetaxel 75 mg/m2 and cisplatin 75 mg/m2 in the first treatment course on day 1 and the same combination plus 5-FU 750 mg/m2/day on days 1-5 in the second course, or the two treatment courses in reversed order. Cycles were repeated every 3 weeks. A pharmacokinetic analysis was performed during the first two cycles.

RESULTS

Full pharmacokinetic data was available for 12 of the 15 patients. Treatment was tolerated well, with frequency of toxicity consistent with the safety profile known for docetaxel, cisplatin and 5-FU. Mean clearance values for docetaxel and cisplatin showed no statistically significant difference across the "triple" and the "double" combination treatments, and the mean pharmacokinetic parameters of all agents were within the ranges for previously reported single agent treatment.

CONCLUSION

No clinically relevant pharmacokinetic interactions between docetaxel, cisplatin and 5-FU used in combination were noticed in this study.

Cognitive and physiological effects of Omega-3 polyunsaturated fatty acid supplementation in healthy subjects

BACKGROUND

It has been reported that Omega-3 fatty acids may play a role in nervous system activity and that they improve cognitive development and reference memory-related learning, increase neuroplasticity of nerve membranes, contribute to synaptogenesis and are involved in synaptic transmission. The aim of this study was to examine the effects of Omega-3 supplementation on some cognitive and physiological parameters in healthy subjects.

MATERIALS AND METHODS

Subjects were tested at the beginning of the experiment and after 35 days. In this period they were supplemented with Omega-3 polyunsaturated fatty acids. A group was supplemented with olive oil (placebo). Tests involving different types of attention were used, i.e. Alert, Go/No-Go, Choice and Sustained Attention. For each test, the reaction time, the event-related potentials by electroencephalogram (EEG) and the electromyography (EMG) of the forefinger flexor muscle were recorded. The Profile of Mood States test (POMS) was also administered.

RESULTS

Blood analyses showed that after Omega-3 supplementation the arachidonic acid/eicosapentaenoic acid ratio (AA/EPA) was strongly reduced. The mood profile was improved after Omega-3 with increased vigour and reduced anger, anxiety and depression states. This was associated with an effect on reactivity with a reduction of reaction time in the Go/No-Go and Sustained Attention tests. The latency of EMG activation was concomitantly reduced in the same tests plus Choice. An EEG frequency shift towards the theta and alpha band were recorded in all the tests after Omega-3.

CONCLUSIONS

Omega-3 supplementation is associated with an improvement of attentional and physiological functions, particularly those involving complex cortical processing. These findings are discussed in terms of the influence of Omega-3 on the central nervous system.