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Alessandra Gennari

Publications and source records attributed to Alessandra Gennari.

17 recordsLinked to original sources
PubMed2006

Lack of benefit of maintenance paclitaxel in first-line chemotherapy in metastatic breast cancer.

PURPOSE: This randomized study compared maintenance paclitaxel with control in metastatic breast cancer patients not experiencing progression after first-line anthracycline/paclitaxel combination chemotherapy. METHODS: Between April 1998 and October 2003, 459 metastatic breast cancer patients received first-line combination chemotherapy with epirubicin or doxorubicin plus paclitaxel. Of these, 255 who had a response or stable disease were then randomly assigned onto the Maintenance Paclitaxel 1 (MANTA1) study, comparing eight courses of maintenance paclitaxel versus control (ie, no additional chemotherapy administration). The primary end point was progression-free survival. RESULTS: The study was prematurely concluded after a futility analysis, which was performed on 215 of the 238 patients randomly assigned within December 2002. Of these, 109 patients were assigned to maintenance paclitaxel and 106 were assigned to stopping chemotherapy. No significant difference in median progression-free survival was observed (8.0 months for maintenance paclitaxel and 9.0 months for control). There was no significant difference in median survival time (28.0 v 29.0 months). When the Bayesian method for monitoring clinical trials was applied to these data, even under an enthusiastic prior distribution, in the posterior distribution there was only an 8.6% chance of observing a 3-month improvement in median progression-free survival in the group receiving maintenance paclitaxel. After these results study accrual was closed. CONCLUSION: Compared with control, the administration of additional courses of paclitaxel in patients who achieve disease control after six to eight courses of first-line anthracycline plus paclitaxel combination chemotherapy does not improve progression-free survival.

Adult↗
PubMed2005

Survival of metastatic breast carcinoma patients over a 20-year period: a retrospective analysis based on individual patient data from six consecutive studies.

BACKGROUND: The expectation of improvement in patient survival with administration of new chemotherapy agents for metastatic breast carcinoma (MBC) is not consistently supported by data from clinical trials, which are often underpowered and have not detected moderate survival advantage. The aim of this study was to evaluate the impact of new agents on prognosis of MBC patients enrolled in clinical trials of first-line chemotherapy. METHODS: Between 1983 and 2001, 640 MBC patients were entered into 6 consecutive trials; the present analysis was limited to patients. The date of diagnosis of metastatic breast disease was used to define 5 arbitrarily chosen 3-year time cohorts, 1983-1986, 1987-1989, 1992-1994, 1995-1997, and 1998-2001. Multivariate proportion of hazard (PH) models were used to evaluate changes in overall survival (OS) and progression-free survival (PFS) over time and to detect changes associated with the use of taxanes, while adjusting for differences in baseline factors among 5 cohorts. RESULTS: Patient characteristics were evenly distributed across the 5 cohorts. Median OS was 18 months, 17.2 months, 19.2 months, 26.1 months, and 23.6 months, respectively, in cohorts 1983-1986, 1987-1989, 1992-1994, 1995-1997, 1998-2001 (P < 0.0001). Age, performance status, relapse-free survival, type of adjuvant treatment, metastatic site, and taxane first-line chemotherapy were all associated with survival. These data failed to provide an indication of temporal trend and suggested a reduction in hazard of death in two cohorts (1995-1997 and 1998-2001) where taxane was added to first-line chemotherapy. CONCLUSIONS: The analysis provided evidence of improvement in prognosis of MBC patients that was associated with use of modern chemotherapeutic agents independent of time.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2005

Acute toxicity.

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Animal Testing Alternatives↗
PubMed2004

New insights into the mechanisms involved in renal proximal tubular damage induced in vitro by ochratoxin A.

The mycotoxin ochratoxin A is a contaminant of human and animal food products. It is a potent nephrotoxin known to damage the proximal tubule. The aim of this work was to investigate the effects of ochratoxin A on a porcine renal proximal tubular epithelial cell line (LLC-PK1), and to identify sensitive endpoints revealing damage at the epithelial barrier level and at the molecular level. Cells exposed for 24 h to 5-10 microM ochratoxin indicated a clear damage to the intactness of the epithelial barrier, as shown by measurements of trans-epithelial resistance and zonula occludens-1 protein expression. At the mitochondrial level we observed alterations of the normal functions, such as an increase of the membrane potential, the formation of straight extensions, and the formation of giant mitochondria. At higher ochratoxin concentrations (50 microM), at which cytotoxicity assays revealed a significant toxicity, alterations of the cytoskeleton organization and induction of apoptosis were evident. In addition, we analyzed the expression of genes by using a cDNA macroarray. Our data indicate that ochratoxin-induced nephrotoxicity can be detected at the barrier and at the mitochondrial level at rather low concentrations, at which conventional cytotoxicity assays are unable to reveal toxic effects.

Animals↗
PubMed2004

Culturing cells without serum: lessons learnt using molecules of plant origin.

To successfully grow cells in serum-free medium is an interesting challenge to cell biology. The use of such media for in vitro cell culture work would be a key contribution to the 3Rs concept, enabling the avoidance of the use of animals and animal products at all stages of the experiment. In addition, numerous problems related to virus infections transmitted by animal serum would be avoided, thus increasing reproducibility. Prolifix is a new reagent of plant origin. It contains a molecule (GCR 1003) that has an activity similar to that of the mitogenic molecules in serum and could be suitable to substitute serum in culture medium. Two epithelial cell lines, LLC-PK1 and Caco-2, were progressively adapted to a special culture medium containing 10% Prolifix in the absence of serum. After adaptation, cell cultures were characterised. We found that these reagents of plant origin could be promising alternatives to serum. However, more work and effort is needed to improve cell adaptation, cell attachment, growth rates as well as freezing/thawing protocols.

Actins↗
PubMed2003

Comparison of the sensitivity of different toxicological endpoints in Caco-2 cells after cadmium chloride treatment.

The human colorectal adenocarcinoma cell line Caco-2 is a widely used in vitro model of the intestinal barrier. Cadmium chloride (CdCl(2)) is a highly toxic metal compound, ubiquitous in the biosphere, able to enter the food chain and to reach the intestinal epithelium, causing structural and functional damages. The aim of this work was to characterise cadmium toxicity in Caco-2 cells and, in particular, to compare the sensitivity of different endpoints revealing damage both on the epithelial barrier and at the cellular or molecular level. After 24-h exposure of the cells to CdCl(2), lactate dehydrogenase (LDH) leakage showed cadmium-induced cell toxicity, significant from 25 microM CdCl(2) and above, and analysis of different cell death pathways indicated the presence of necrosis after treatment with 50 microM CdCl(2). At the molecular level, we observed an increase in the protective protein heat shock protein 70 (HSP70), starting at 10 microM CdCl(2). At the barrier level, transepithelial electrical resistance (TEER) decreased while paracellular permeability (PCP) significantly increased after the treatment, showing an EC(50) of 6 and 16 microM CdCl(2), respectively, and indicating the loss of barrier integrity. In conclusion, our data reveal that CdCl(2) toxicity in Caco-2 cells can be detected at the barrier level at very low concentrations; also, HSP70 was shown to be a sensitive marker for detecting in vitro cadmium-induced toxicity.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2003

Sensitive endpoints for evaluating cadmium-induced acute toxicity in LLC-PK1 cells.

Cadmium chloride (CdCl(2)) is a nephrotoxicant that causes damage to the proximal tubular epithelium. In vivo, it increases the permeability of epithelial surfaces, while in vitro, it acts on active trans-epithelial ion transport. The purpose of this study was to investigate CdCl(2) effects on a porcine renal proximal tubular epithelial cell line (LLC-PK1), and, in particular, to identify sensitive endpoints revealing damage both at the epithelial barrier level and at the molecular level. After exposure of the cells to CdCl(2), trans-epithelial resistance (TER) decreased while paracellular permeability (PCP) increased, indicating a structural alteration of the junctional complex. At the molecular level, we observed an increase in protective proteins, such as metallothioneins (MTs) and heat shock proteins (HSP70), starting from 25 microM CdCl(2), together with alterations in cytoskeleton organization. Production of reactive oxygen species (ROS) was also evident, indicating cellular oxidative stress. Our data indicate that CdCl(2) toxicity can be detected at the barrier level and at the molecular level at low concentrations, at which cytotoxicity assays are unable to show any damage. Therefore, these endpoints should prove very useful in studying heavy metal-induced acute toxicity. Exposure of the cells to higher concentrations of CdCl(2) (50 microM) revealed the initiation of apoptosis, mediated by caspase-3.

Acute Disease↗
PubMed2002

Organotin-induced apoptosis occurs in small CD4(+)CD8(+) thymocytes and is accompanied by an increase in RNA synthesis.

The organotin compounds di-n-butyltin dichloride (DBTC) and tri-n-butyltin chloride (TBTC) induce thymus atrophy in rats. At low doses they inhibit immature thymocyte proliferation, whereas at higher doses in particular TBTC induces apoptotic cell death. In vitro, a similar concentration-effect relationship was observed, i.e. low concentrations inhibit DNA and protein synthesis and higher concentrations induce apoptosis. The mechanism of apoptosis by organotins has been partly investigated, but their capacity to inhibit protein synthesis seems to contradict with the idea that macromolecular synthesis is required for organotin-induced apoptosis. Therefore, we aimed to evaluate the relation between apoptosis and the synthesis of RNA and proteins, with a focus on the apoptosis-sensitive thymocyte subset. Results showed that DBTC increases RNA synthesis in particular in the subset of small CD4(+)CD8(+) thymocytes, which normally shows a high incidence of DNA fragmentation. Moreover, the RNA synthesis inhibitor actinomycin D or the protein synthesis inhibitor cycloheximide protected cells from apoptosis by DBTC or TBTC. Although organotin compounds increase synthesis of the heat shock protein HSC73/HSP72, heat shock treatment did not initiate apoptosis in thymocytes, neither antagonized organotin-induced apoptosis. This indicates that synthesis of heat shock proteins is not related to organotin-induced increase of RNA synthesis, and that other RNA-molecules are probably involved.

Animals↗
PubMed2002

Identification by DNA macroarray of nur77 as a gene induced by di-n-butyltin dichloride: its role in organotin-induced apoptosis.

The thymotoxic organotin compounds di-n-butyltin dichloride (DBTC) and tri-n-butyltin chloride (TBTC) are known to induce apoptosis in vitro in rat thymocytes. They also affect macromolecular synthesis, inhibiting DNA synthesis and increasing RNA synthesis. Since these RNA molecules, likely to be involved in the initiation of the apoptotic process, have not been identified yet, the purpose of this research was to characterize by a cDNA macroarray the expression of genes involved in DBTC-induced apoptosis. We found that nur77 was rapidly transcripted in vitro following exposure of freshly isolated rat thymocytes to 3 microM DBTC. nur77 induction has also been observed in vivo after treatment of rats with apoptotic doses (60 mg/kg body wt) of DBTC. The products of nur77 are known to be involved in the apoptotic process, as nur77 is a transcription factor expressed in response to T-cell receptor-mediated apoptosis in immature T cells. Antisense oligonucleotide inhibition of nur77 expression prevented apoptosis induced by DBTC, supporting a role for nur77 in organotin-induced apoptotic cell death.

Animals↗
PubMed2002

Pharmacokinetics and pharmacodynamics of combination chemotherapy with paclitaxel and epirubicin in breast cancer patients.

AIMS: To investigate the pharmacokinetics and pharmacodynamics of epirubicin and paclitaxel in combination, as well as the effects of paclitaxel and its vehicle Cremophor EL on epirubicin metabolism. METHODS: Twenty-seven female patients with metastatic breast cancer received epirubicin 90 mg m-2 i.v. followed 15 min or 30 h later by a 3 h i.v. infusion of paclitaxel 175, 200 and 225 mg m-2. Plasma concentrations of paclitaxel, epirubicin and epirubicinol were measured and the relationship between neutropenia and drug pharmacokinetics was evaluated using a sigmoid maximum effect (Emax) model. Finally, the influence of paclitaxel and Cremophor EL on epirubicin metabolism by whole blood was examined. RESULTS: An increase in epirubicinol plasma concentrations occurred after the start of the paclitaxel infusion, resulting in a significant increase in the area under the plasma concentration-time curve (AUC) of epirubicinol (+0.5 micromol l-1 h [95% CI for the difference: 0.29, 0.71],+0.66 micromol l-1 h [95% CI for the difference: 0.47, 0.85] and +0.82 micromol l-1 h [95% CI for the difference: 0.53, 1.11] at paclitaxel doses of 175, 200 and 225 mg m-2, respectively), compared with epirubicin followed by paclitaxel 30 h later (0.61+/-0.1 micromol l-1 h). A significant increase in epirubicin AUC (+0.74 micromol l-1 h [95% CI for the difference: 0.14, 1.34] and +1.09 micromol l-1 h [95% CI for the difference: 0.44, 1.74]) and decrease in drug clearance (CLTB) (-25.35 l h-1 m-2[95% CI for the difference: -50.18, -0.52] and -35.9 l h-1 m-2[95% CI for the difference -63,4,-8,36]) occurred in combination with paclitaxel 200 and 225 mg m-2 with respect to the AUC (3.16+/-0.6 micromol l-1 h) and CLTB (74.4+/-28.4 l h-1 m-2) of epirubicin followed by paclitaxel 30 h later. An Emax relationship was observed between neutropaenia and the time over which paclitaxel plasma concentrations were equal to or greater than 0.1 micromol l-1 (tC0.1). The tC0.1 value predicted to yield a 50% decrease in neutrophil count was 7.7 h. Finally, Cremophor EL markedly inhibited the metabolism of epirubicin to epirubicinol in whole blood. CONCLUSIONS: Paclitaxel/Cremophor EL affects the disposition of epirubicinol and epirubicin. Furthermore, the slope factor of the Emax relationship between neutropenia and tC0.1 of paclitaxel suggests that the drugs might also interact at the pharmacodynamic level.

Adult↗
PubMed2002

Pemetrexed: a promising new treatment for breast cancer.

Metastatic breast cancer is a chemotherapy-responsive disease, and significant palliation of cancer-related symptoms can be achieved with effective treatment. New treatments are needed because patients with metastatic breast cancer commonly out-live the effectiveness of currently available cytotoxic and hormonal treatments. Pemetrexed is a novel antimetabolite that inhibits three enzymes critical in purine and pyrimidine biosynthetic pathways: thymidylate synthase, dihydrofolate reductase, and glycinamide ribonucleotide formyltransferase. Several phase II studies of pemetrexed have showed objective response rates of more than 30% in minimally pretreated metastatic breast cancer patients and approximately 20% in more heavily pretreated patients. Pemetrexed is associated with limited toxicity when administered with folic acid and vitamin B(12) supplementation and is therefore a promising agent both for palliative treatment of metastatic disease and for incorporation into combination regimens for treating newly diagnosed metastatic and early-stage breast cancer.

Antimetabolites, Antineoplastic↗
PubMed2002

Pharmacokinetic-pharmacodynamic relationships of the anthracycline anticancer drugs.

The anthracycline glycoside antibiotics represent a group of potent anticancer agents with a wide spectrum of activity against solid tumours and haematological malignancies, and are the mainstay of a large number of clinical protocols for the treatment of adult and childhood neoplastic diseases. Their clinical activity is limited, however, by acute and chronic adverse effects. Myelosuppression, predominantly neutropenia and leucopenia, is the dose-limiting toxicity; in addition to this, mucositis, nausea, vomiting and alopecia are frequent, whereas hepatopathy, characterised by elevated bilirubin concentrations, occurs less frequently. Cardiotoxicity is a major adverse effect of the anthracycline antibiotics and can be acute or chronic; in the acute setting, electrocardiographic abnormalities may be seen, including ST-T elevations and arrhythmias, but chronic cardiotoxicity represents a serious adverse effect that may be lethal due to the development of irreversible, cumulative dose-dependent, congestive cardiomyopathy. The occurrence of toxicity displays a marked interindividual variation, and for this reason the pharmacokinetics and pharmacodynamics of anthracyclines have been extensively investigated in order to identify integrated models that can be used in the clinical setting to prevent the development of serious toxicity, mainly leucopenia, and maximise tumour exposure. Pharmacokinetics has been recognised to influence both the toxicity and the activity of anthracyclines; in particular, there is increasing evidence that the mode of administration plays an important role for cumulative cardiotoxicity and data indicate that bolus administration, rather than continuous infusion, appears to be an important risk factor for anthracycline-induced cardiomyopathy, thus implying that this type of toxicity is maximum concentration-dependent. On the contrary, exposure to the drug, as measured by area under the curve, seems best related to the occurrence of leucopenia. Finally, the development of pharmacokinetic-pharmacodynamic models allows the simulation of drug effects and ultimately dose optimisation in order to anticipate important toxicities and prevent their occurrence by the administration of prophylactic treatments.

Antibiotics, Antineoplastic↗
PubMed2002

Weekly docetaxel/paclitaxel in pretreated metastatic breast cancer.

The purpose of our study was to evaluate the feasibility and efficacy of weekly docetaxel/paclitaxel in pretreated advanced breast cancer patients. Twenty-six patients with metastatic breast cancer were included in this study. Three different schedules of treatment were administered. The starting schedule, A1, consisted of docetaxel 60 mg/m2 on day 1 plus paclitaxel 60 mg/m2 over 1 hour, weekly for 18 weeks; this schedule was considered feasible if at least 70% of the planned doses were given on time and without reduction. Schedule A2 consisted of the same doses administered on days 1 and 8 every 3 weeks, and schedule B consisted of docetaxel 25 mg/m2 followed by paclitaxel 40 mg/m2 for 1 hour on days 1 and 8 every 3 weeks for a total of 6 cycles. All patients had received prior anthracyclines, and 19 patients were pretreated with taxanes. Seventy-seven percent of patients had received at least 2 prior lines of chemotherapy. Twenty-five patients are assessable for toxicity and efficacy. A total of 109 cycles of chemotherapy have been administered, with a median of 4 cycles per patient (range, 1-8 cycles). The median delivered dose intensity was 27 mg/m2/week for paclitaxel (range, 18-50 mg/m2/week) and 17 mg/m2/week (range, 12-39 mg/m2/week) for docetaxel. Six patients received schedule A1. This schedule was considered not feasible due to neutropenia grade > 2, mucositis, and diarrhea grade 2, which required dose reduction/omission in 33% of administrations. For this reason, treatment in the following 5 patients was omitted on day 15 (schedule A2). Schedule B was found to be more feasible with 16% of dose reductions/omissions. The overall response rate was 68% (95% CI, 50%-86%) with a median duration of response of 10 months (range, 2-18+ months). Treatment was well tolerated; myelosuppression was rare and grade 3 cutaneous toxicity was observed in only 2 patients. In conclusion, weekly docetaxel/paclitaxel is active at low dosages and was well tolerated as salvage chemotherapy in metastatic breast cancer. This regimen represents a valid option as a salvage treatment in taxane- and anthracycline-pretreated patients.

Adult↗