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Background: Preclinical and retrospective clinical data suggest that ≥3T is a biomarker for poor prognosis and resistance to paclitaxel in breast cancer (BC). Preclinical studies have demonstrated that Ixa has activity in ≥3T over-expressing xenograft models resistant to taxanes and Ixa has shown clinical activity in BC patients with high ≥3T mRNA levels [Horak et al., J Clin Oncol 27:15s, 2009 (suppl; abstr 3587]. Dako and BMS have developed an IHC assay for detection of ≥3T to explore the potential of ≥3T as a biomarker to select BC patients that may benefit from Ixa. A neoadjuvant BC study comparing ixa to weekly paclitaxel employs this assay to assess ≥3T expression levels in patients’ tumor samples. Here we describe the application and initial validation testing of the assay in BC tumor samples. Methods: An IHC assay employing a murine monoclonal anti-≥3T antibody (TUJ1) was developed to assess ≥3T expression in formalin-fixed paraffin-embedded tissue specimens. Banked specimens for initial testing included 233 cases of invasive BC. Results: Patterns of ≥3T staining were typically homogeneous cytoplasmic staining with normal tissue elements such as endothelial cells and nerve cells serving as internal positive controls. Staining intensity was scored as 0, 1+, 2+ or 3+ with 0 being no visible staining and 2+ being equal to that of the internal positive control. Tumors with ≥50% cells staining ≥2+ were defined as positive for ≥3T based on previous published studies. Of the 233 breast tumors, 81 (35%) were positive and 152 (65%) were negative for ≥3T expression. HER2 status was defined for 128 of these specimens, with 37 of them (29%) found to be HER2 positive. Comparison of the samples with defined HER2 status demonstrated similar patterns of ≥3T expression, with 15 (40.5%) of the HER2+ samples being positive for ≥3T and 31 (34.1%) of HER2- specimens expressing elevated levels of ≥3T. In pathologist training exercises the inter-reader and intra-reader agreement of ≥3T scoring exceeded 85%. Antigen stability has been confirmed and other assay validation efforts are ongoing. Conclusions: These findings are consistent with previously reported data on ≥3T expression in breast cancer, and support the use of this ≥3T IHC assay in studies with ixabepilone. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-08-06.

Resume Introduction Plusieurs auteurs ont evalue la relation entre l’expression de la β-tubuline de classe III et le devenir des patients porteurs d’un cancer du poumon non a petites cellules (CPNPC) traites par des agents antitubulines (AAT). Etat des connaissances Un haut niveau d’expression de β-tubuline de classe III a ete correle avec une moindre reponse ou une survie plus courte chez les patients presentant un CPNPC avance traite par taxanes et vinorelbine. Deux etudes ont montre que les patients traites par paclitaxel dont les tumeurs exprimaient un haut niveau de β-tubuline de classe III avaient une moindre reponse et une survie plus vite, tandis que cette variable n’avait pas de valeur predictive chez les patients ne recevant pas d’AAT. A l’oppose, l’analyse des tumeurs des patients operes porteurs d’un CPNPC de l’essai JBR-10 a montre que la chimiotherapie par cisplatine/vinorelbine semblait neutraliser la valeur pronostique negative de l’expression de β-tubuline de classe III et que le benefice de la chimiotherapie etait plus important pour les patients ayant un haut niveau d’expression. Perspectives Dans le CPNPC avance, un haut niveau d’expression de β-tubuline de classe III pourrait orienter le choix de la chimiotherapie vers un protocole sans taxanes. Les epothilones apparaissent potentiellement interessantes dans ce contexte. Conclusions L’expression de la β-tubuline de classe III emerge comme un marqueur de resistance aux taxanes dans le CPNPC avance, ainsi qu’un marqueur pronostic pour le devenir des patients ayant une maladie localisee.

Single-agent gemcitabine has shown encouraging results in patients with mantle cell lymphoma (MCL). This phase II study further explored the potential of a gemcitabine-based regimen in patients with relapsed or refractory MCL. Patients70 years old received the PDG regimen: gemcitabine (1000 mg/m(2), days 1 and 8), dexamethasone (40 mg/m(2), days 1-4), and cisplatin (100 mg/m(2), day 1). Patients/=70 years of age received dexamethasone and gemcitabine only (DG regimen). Thirty patients (12 in the DG group, 18 in the PDG group) with a median age 66.5 years (range, 47-81) received a median of six cycles in both groups. The overall response rate was 36.4% [95% confidence interval (CI), 15.2% to 64.6%] with the DG regimen and 44.4% (95% CI 24.6% to 66.3%) with the PDG regimen. The median progression-free survival was 3 months (95% CI 0.0-7.9) in the DG group and 8.5 months (95% CI 4.8-12.2) in the PDG group. With a median follow-up of 38.8 months, 13 patients (including 11 given PDG) are still alive. DG was well tolerated, and thrombocytopenia was the most prevalent toxicity in patients receiving PDG. Both regimens deserve to be further investigated as a backbone for combination chemotherapy in patients with MCL.

Patients with acute myeloblastic leukemia (AML) are divided according to the French American British (FAB) classification into eight subgroups (M0 to M7) on the basis of their degree of maturation/differentiation. However, even if immunophenotypical characterization by flow cytometry is routinely used to distinguish between AML and acute lymphoblastic leukemia (ALL), it is not yet well established for the identification within the AML subgroups. Here we show that certain subgroups of AML can be identified with a good accuracy (80% of the patients we analyzed) by means of the expression of specific markers.

Introduction Une atteinte renale est exceptionnelle au cours du syndrome hyperIgD (SHID) par deficit recessif en Mevalonta Kinase (MVK). Nous rapportons un nouveau cas de glomerulonephrite rapidement progressive (GNRP). Observation La patiente âgee de 29 ans presente depuis l’âge de 6 mois des poussees auto-inflammatoires. Le SHID a ete diagostique 8 ans auparavant : IgD a 340 mg/L, IgA a 16,2 g/L ; MVK lymphocytaire indosable ; mevalonaturie a 4,3 mmol/mmol creat ; 2 mutations heterozygotes a l’analyse du gene MVK. Deux mois apres la fin d’une grossesse normale, lors d’une poussee auto-inflammatoire cutanee, elle presente un syndrome glomerulaire aigu avec proteinurie 1,95 g/24 h, creatininemie 321 μmol/L (anterieurement : 52). Le bilan immunologique s’avere normal en dehors des IgD : 810 mg/L, IgA : 15,5 g/L (IgA1 15,4 g/L, IgA2 0,4 g/L), avec simple restriction d’heterogeneite et faible cryoglobulinemie de type 3 (IfA 4 mg/L, IgG 2,3 mg/L, FR neg). Sur la biopsie renale, 50 % des 23 glomerules presentent une proliferation extracapillaire circonferentielle ou segmetaires, avec des necroses fibrinoides et quelques axes mesangiaux un peu hypercellulaires, avec des depots mesangiaux d’IgA, IgG, C3, kappa et lambda. Sous corticotherapie (3 bolus 250 mg puis 0,5 mg/kg) et Anakinra (50 μg/semaine) introduit 6 mois plus tard, l’evolution est rapidement et durablement favorable : a 6 et 12 mois respectivement la creatininemie est a 117 puis 62 μmol/L, la proteinurie a 0,41 puis 0,17 g/24 h. Apres 36 mois sous seul Anakinra la creatininemie est a 66 μmol/L avec des anomalies urinaires mineures (proteinurie 39 mg/mmol creat, GR 21/mm3) ; il n’est survenu aucune poussee auto-inflammatoire significative bien que les IgD resent a 369 mg/L et les IgA a 17 g/L. Conclusion Une glomerulopathie n’est signalee que chez 4 % des cas d’une cohorte de 50 patients avec SHID. Trois cas rapportes font etat 2 fois d’une amlyose AA renale et deux fois d’une GNRP pauci-immune a ANCA negatifs. Nous rapportons donc un nouveau type possible d’atteinte renale au cours du SHID, sur le mode d’une GNRP a depots d’IgA qui repond remarquablement au traitement par Anakinra, antagoniste du recepteur de l’IL-1.

Introduction Les atteintes renales au cours des hemopathies lymphoproliferatives sont bien connues. Celles liees aux hemopathies myeloides sont plus rares. Observation Un homme de 76 ans, ayant pour antecedents une anemie refractaire par exces de blaste de type 2 (AREB) et un lymphome cutane T diagnostique depuis 1 an, est adresse en decembre 2015 pour syndrome glomerulaire (proteinurie 2 g/L ; hematurie 13 elements/mm3) associee a une insuffisance renale evoluant depuis 4 mois (creatinine 125 μmol/L ; DFG 48 mL/min/1,73 m2, CKD-EPI). Le bilan immunologique (Fan, ANCA, complement, cryoglobulinemie, anticorps anti-MBG et PLA2-R) est negatif. Une PBR effectuee en janvier 2016 retrouve de fins depots extramembraneux (IgA, IgG et C3) et un infiltrat interstitiel mononuclee polymorphe. Le diagnostic de GEM paraneoplasique est pose. En fevrier 2016, il presente une insuffisance renale aigue non obstructive (creatinine 330 μmol/L, proteinurie 1,76 g/j ; hematurie 50 elements/mm3) satellite d’une acutisation de l’AREB en leucemie aigue myeloblastique (LAM). Une seconde PBR retrouve, en plus de la GEM, une infiltration tumorale constituee de cellules blastiques dont le profil en immunohistochimie (CD34+, CD117+, CD15+, Ki67+) est compatible avec la LAM. Un traitement associant hydroxyuree et corticoides a 0,5 mg/kg/jour est instaure en urgence, dans l’attente de la mise sous azacitidine (traitement de reference). Une recuperation partielle de la fonction renale a ete observee en 15 jours (creatinine a 185 μmol/L). Le traitement est actuellement suspendu du fait de complications infectieuses. Conclusion Deux atteintes renales distinctes associees aux hemopathies myeloides sont retrouvees chez ce patient : une GEM paraneoplasique liee a l’AREB puis un infiltrat tumoral renal d’une LAM secondaire. Quelques cas de GEM secondaires a des syndromes myleodysplasiques ont ete decrits [1] . Le pronostic renal reste lie a la reponse hematologique au traitement.

The macrocyclic lathyrane polyester Euphorbia factor L10 (1a) has been obtained from the seeds of the caper spurge (E. lathyris). The interaction of L10 (1a) and its acetyl derivative (1b) with P-glycoprotein, a multidrug transporter overexpressed in cancer cells and responsible for resistance to chemotherapy, was investigated. The results established lathyrane diterpenoids as a novel chemotype for P-glycoprotein inhibitors.

Several investigators have addressed the relationship between expression of class III beta-tubulin and outcome in patients with nonsmall cell lung cancer (NSCLC) treated with tubulin-binding agents (TBA).High expression of class III beta-tubulin has been found to be correlated with low response rates and reduced survival in advanced NSCLC patients treated with taxane/vinorelbine--containing regimens. Two studies have shown that patients receiving paclitaxel whose tumours expressed high levels of class III beta-tubulin had a lower response rate and shorter survival, whereas this variable was not found to be predictive in patients receiving regimens without TBA. Conversely, analysis of samples from operable NSCLC patients in the JBR-10 trial showed that cisplatin/vinorelbine chemotherapy seemed to overcome the negative prognostic effect of high class III beta-tubulin expression and that the greatest benefit from chemotherapy was observed in patients with high class III beta-tubulin expression.In advanced NSCLC, high betaIII tubulin expression may prompt selection of taxane-free regimens as the preferred initial treatment approach. The epothilones may fulfil such a role in the treatment of NSCLC.betaIII tubulin expression is emerging as a valuable biomarker for taxane resistance in advanced disease, as well as offering prognostic information for outcomes among patients with earlier stage disease.

In 2002, the French Federation of Comprehensive Cancer Centers published clinical practice guidelines (CPGs) for the management of carcinomas of unknown primary (CUP).A controlled "before-after" study at two centers (experimental in Lyon, France and control in Edmonton, Canada) to assess the impact of CPGs on CUP management. Fifty-CUP patients treated in 2000-2001, i.e. before CPG publication, and 50 patients treated in 2003-2004, were analyzed for both centers.In both groups, compliance for diagnostic workup was the same before or after CPGs publication. Non-adenocarcinoma histology and performance status (PS)2 were independent factors for CPGs compliance. In the experimental group, 75% of patients underwent inappropriate investigations. The proportion of patients from this group with unfavourable clinicopathologic entity and PSor = 1, who received cisplatin-based chemotherapy did not significantly change (2000-2001: 27% vs. 2003-2004: 37.5%; P = 0.45). However, most patients treated in the pre period received organ-specific regimens, while most patients treated in the post period received taxane or gemcitabine-based regimens. Patients from the control group generally received taxane/carboplatin.Our study show that simply distributing CUP CPGs did not change practice and underline the necessity to disseminate and implement CPGs, both to oncologists and organ-specialist physicians.

DNA repair mechanisms constitute major defences against agents that cause cancer, degenerative disease and aging. Different repair systems cooperate to maintain the integrity of genetic information. Investigations of DNA repair involvement in human pathology require an efficient tool that takes into account the variety and complexity of repair systems. We have developed a highly sensitive damaged plasmid microarray to quantify cell lysate excision/synthesis (ES) capacities using small amounts of proteins. This microsystem is based on efficient immobilization and conservation on hydrogel coated glass slides of plasmid DNA damaged with a panel of genotoxic agents. Fluorescent signals are generated from incorporation of labelled dNTPs by DNA excision-repair synthesis mechanisms at plasmid sites. Highly precise DNA repair phenotypes i.e. simultaneous quantitative measures of ES capacities toward seven lesions repaired by distinct repair pathways, are obtained. Applied to the characterization of xeroderma pigmentosum (XP) cells at basal level and in response to a low dose of UVB irradiation, the assay showed the multifunctional role of different XP proteins in cell protection against all types of damage. On the other hand, measurement of the ES of peripheral blood mononuclear cells from six donors revealed significant diversity between individuals. Our results illustrate the power of such a parallelized approach with high potential for several applications including the discovery of new cancer biomarkers and the screening of chemical agents modulating DNA repair systems.

Efflux pumps located in the bacterial membranes are responsible for low level resistance to antibiotics, considered not to be relevant in the clinic and thus often neglected. However, these pumps contribute to the emergence of high level antibiotic resistance mechanisms, which are responsible for severe complications during the treatment of infectious diseases. Therefore it is necessary to take into account these pumps while developing novel antibacterial agents. Among these new research strategies, the development of efflux pump inhibitors seems to be an attractive approach to restore the activity of some "classical" antibiotics and to limit the emergence of multiresistant strains associated with hospital-acquired infections. In this review, we focalise on Staphylococcus aureus efflux pumps and their potential inhibitors.

As microtubules are essential in many cell functions, they have been used as a target of a variety of anticancer drugs that are grouped as stabilizing (taxanes) and destabilizing (vinca-alkaloids, colchicinoids) microtubule agents. It appears clearly now that the dynamic behaviour more than modifications of microtubule mass are altered by antitubulin agents in the range of serum concentrations obtained after administration in humans. While the role of microtubule associated proteins in the regulation of microtubule dynamics has been extensively studied, there is a growing body of data suggesting that tubulin folding could also play an important role in microtubule dynamics. We review the current knowledge regarding tubulin folding pathways, their relation to disease, and their possible influence on microtubule dynamics.

The French Cancer Plan 2003-2007 has made translational research central to its research programme, to ensure the care-research continuum and the quickest application possible for the most recent discoveries, for the patients' benefit. This is a new field of research, still little-known or ill-understood. A working group, composed of physicians and researchers from academic research and industrial research, sought to define translational research in cancerology and define the issues at stake in it. Translational research needs to develop in close connection with the patients in order to enable a bi-directional flow of knowledge from cognitive research toward medical applications and from observations made on patients toward cognitive research. Placed under the aegis of the French National Cancer Institute and Leem Research, the group has put forth a strategy for implementing translational research in cancerology in France to make it attractive, competitive and efficient and to foster the development of public-private partnerships.

Background: Patients with relapsing or refractory multiple myeloma have poor prognosis. Few compounds are active in these patients and response duration remains short. We report the results of an open phase II trial evaluating the efficacy and safety of fotemustine monotherapy. Patients and methods: Twenty-one patients with relapsing (17) or refractory (four) multiple myeloma received fotemustine 100 mg/m 2 on an outpatient basis on days 1 and 8 of the induction cycle, followed after a 6-week rest period by fotemustine 100 mg/m 2 every 3 weeks until progression or unacceptable toxicity. Fotemustine pharmacokinetics during the first day of induction was compared between patients with normal or abnormal renal function. Results: Five of 20 eligible patients had an objective response giving an intention-to-treat response rate of 25% [95% confidence interval (CI) 6% to 44%] and a 35.7% response rate (95% CI 11% to 61%) in the 14 patients having received at least four injections of fotemustine. The median time to objective response was 8.9 months. The median times to progression and survival were 13.8 and 23.1 months, respectively, with a 2-year survival rate of 49%. The main toxicity was myelosuppression with grade 3–4 neutropenia and thrombocytopenia in 66% and 71% of patients, respectively. There was one toxic death by sepsis after induction. The pharmacokinetic parameters in renal-impaired patients were not significantly different from those in patients with normal renal function with a similar incidence of grade 3–4 toxicity in both groups. Conclusions: Fotemustine as a single agent has definite activity in patients with relapsing or refractory multiple myeloma, with acceptable toxicity and can be administered at conventional doses in patients with mild or moderate renal impairment.

Multidrug resistance due to P-glycoprotein is a serious impediment to successful chemotherapy of cancer. Previous studies have shown that natural compounds such as prenyl flavonoids are able to modulate the multidrug resistance phenotype of P-glycoprotein-positive cancer cells. A fraction from the dichloromethane extract of a common Guadalupe Ficus, Ficus citrifolia was studied for its direct interaction with the purified C-terminal cytosolic domain of P-glycoprotein, and for its induced accumulation and cytotoxicity of vinblastine and daunomycin in two model cell lines overexpressing P-glycoprotein, namely K562/R7 and MESSA/Dx5. The fraction bound with high affinity to P-glycoprotein C-terminal cytosolic domain and was as efficient as cyclosporin A to increase intracellular accumulation of daunomycin in K562/R7 leukemic cells. Moreover, the fraction markedly enhanced the cytotoxic effect of vinblastine on the growth of MESSA/Dx5 cells. These results suggest that Ficus citrifolia possesses important therapeutic potential for improving the efficacy of cancer chemotherapy.

A multicentre phase II trial was conducted to evaluate the efficacy and toxicity of gemcitabine in patients with refractory or relapsed indolent non-Hodgkin's lymphoma. Thirty-six patients were enrolled onto the study, including 11 cases of mantle cell lymphoma (MCL), 10 cases of chronic lymphocytic leukaemia (CLL)/lymphocytic lymphoma, nine cases of follicular lymphoma, four cases of lymphoplasmacytic lymphoma and two cases of T-cell lymphoma. Gemcitabine 1 g/m(2) was administered as a 30-min infusion on d 1, 8 and 15 of a 28-d schedule, up to a maximum of six cycles. Complete responses were observed in two patients with MCL, and partial responses were observed in seven patients, including three patients with CLL/lymphocytic lymphoma, two patients with T-cell lymphoma, one patient with MCL and one patient with follicular lymphoma. Minor responses were observed in three patients, including two patients with MCL and one patient with CLL. The median duration of response was 150 d and the overall progression-free survival was 342 d. Haematological toxicity was observed as grade 3-4 leucopenia in 12 patients (33%) and grade 3-4 thrombocytopenia in 18 patients (50%). Severe non-haematological toxicity included one case of fatal veno-occlusive disease, one case of thrombotic microangiopathy leading to terminal renal failure, one case of capillary leak syndrome, one case of myocardial infarction and drug-induced fever in two patients. These data suggest that gemcitabine displays activity in patients with MCL and CLL/lymphocytic lymphoma. Haematological toxicity was frequent in these heavily treated patients. Severe non-haematological toxicity was significant and should be taken into account in the design of future trials.

Patients receiving high-dose cyclophosphamide as a conditioning regimen for peripheral stem cell collection are subjected over a short period of time to significant exposure to reactive oxygen species (ROS). All these patients undergo profound leucopenia. Various other short-term toxicities are observed in a fraction of the patients, including febrile aplasia requiring hospitalization, thrombocytopenia and mucositis. Although stem cell collection is feasible in the majority of patients stimulated with haematopoietic growth factors, in some instances, graft collection cannot be performed because of insufficient concentrations of stem cells in peripheral blood. There is currently no predictive assay to determine which patients treated with high-dose cyclophosphamide have a high risk of febrile aplasia or will successfully undergo cytaphereses for stem cell collection. In order to identify such predictive factors, we analysed the level of expression before treatment of various ROS detoxification mechanisms in the peripheral blood of 37 patients receiving high-dose cyclophosphamide for lymphoproliferative diseases. Various parameters involved in the metabolism of ROS were measured in plasma and/or erythrocytes, including superoxide dismutase, glutathione, glutathione peroxidase, glutathione reductase and malondialdehyde. High levels of erythrocyte superoxide dismutase before cyclophosphamide therapy were correlated with an increased risk of hospitalization for febrile aplasia (65% vs. 29%, P = 0.013). High superoxide dismutase and low erythrocyte glutathione reductase were associated with lower CD34 yields. These data suggest that components of the ROS detoxification system modulate the degree of short-term toxicity of cyclophosphamide and could be used as predictive markers in individual patients.

We performed a multicenter case-control study on incident cases of giant cell arteritis and polymyalgia, and tested for viruses known to induce multinucleated giant cells in human pathology. IgM directed against Human parainfluenza type 1 virus were shown to be significantly associated with the onset of the disease in 40% of the cases, versus 20% of the controls.

Variants of the human K562 were developed against the nucleoside analogues cytosine arabinoside, 2 chlorodeoxyadenosine, fludarabine and gemcitabine. The resistant lines displayed a high degree of cross-resistance to all nucleoside analogues, with little or no cross resistance to other agents. There was a profound accumulation defect of the different nucleoside analogues in all of the variants. There was a strong overexpression of 5'nucleotidase, measured by rt-PCR and enzyme activity, in all resistant variants. There was a two fold increase of ribonucleotide reductase in the fludarabine resistant line and increased expression of purine nucleoside phosphorylase in the 2 chlorodeoxyadenosine selected line. Karyotypic analysis revealed the loss of a 6(q16;q22) deletion present in the parental line in all of the resistant lines. This portion of chromosome 6 has been shown to contain the gene for 5'nucleotidase. Early events in the transport and metabolism appear to be involved in the resistance mechanisms to nucleoside analogues and are responsible for broad cross resistance to this family of compounds.

Resistant variants of the human leukaemic line K562 were developed using selection with the deoxynucleoside analogues cytosine arabinoside, 2-chlorodeoxyadenosine, fludarabine and gemcitabine. The resistant lines displayed a high degree of cross resistance to all deoxynucleoside analogues, with little or no cross resistance to other agents. There was a profound accumulation defect of all nucleoside analogues in the resistant variants but no significant defect in nucleoside transport in any of the variants. 5' nucleotidase activity was strongly increased and deoxycytidine kinase activity was moderately reduced in all of the resistant variants, resulting in reduced accumulation of triphosphate analogues. In addition a deletion in one of the alleles of the deoxycytidine kinase was detected in the fludarabine-resistant line. Ribonucleotide reductase activity was found to be strongly increased in the gemcitabine-selected line and purine nucleoside phosphorylase was increased in the 2-chlorodeoxyadenosine-selected line. Free nucleotide pools were increased in the 2-chlorodeoxyadenosine-selected line. There was no expression of the mdr1 gene by the resistant lines. Karyotypic analysis and FISH experiments using a 6q21 specific probe showed alterations in the 6(q16-q22) region which contains the 5'-nucleotidase gene. Early events in the activation and degradation of deoxynucleoside analogues appear to constitute common mechanisms of resistance to these compounds.

Although suspected, a viral etiology has never been proven in giant cell arteritis (GCA). We tested for viruses known to induce multinucleated giant cells in human pathology, which include the parainfluenza viruses (HPIV), respiratory syncytial virus, measles virus, herpesviruses type 1 and 2, and the Epstein-Barr virus.A multicenter case-control study on incident cases of temporal arteritis (TA) and polymyalgia rheumatica (PMR). Population based age and sex matched controls were randomly selected. Serological tests for IgG and IgM directed against the viruses listed above were performed, on blood samples taken at the time of clinical diagnosis.Three hundred five new patients were included over a 5 year period, of whom 159 presented with positive biopsy TA, 70 with negative biopsy TA, and 76 with negative biopsy PMR. Thirty-eight percent of cases versus 20.9% of controls were positive for IgM directed against HPIV (p = 0.00005). The association was stronger in the positive TA subgroup [positivity rate 43.31%; odds ratio with controls 2.89 (95% CI 1.82-4.60, p = 0.000006)] than in the PMR or negative biopsy TA subgroups. Only HPIV type 1 was associated with the disease, regardless of the season or the geographical origin of the cases. Positivity rates for HPIV types 2 and 3 and for the other viruses tested were similar in cases and controls.Our findings suggest that reinfection with HPIV type 1 is associated with the onset of GCA in a subset of patients, particularly in cases with positive TA biopsy.

Variants of the human K562 were developed against the nucleoside analogues cytosine arabinoside, 2 chlorodeoxyadenosine, fludarabine and gemcitabine. The resistant lines displayed a high degree of cross-resistance to all nucleoside analogues, with little or no cross resistance to other agents. There was a profound accumulation defect of the different nucleoside analogues in all of the variants. There was a strong overexpression of 5'nucleotidase, measured by rt-PCR and enzyme activity, in all resistant variants. There was a two fold increase of ribonucleotide reductase in the fludarabine resistant line and increased expression of purine nucleoside phosphorylase in the 2 chlorodeoxyadenosine selected line. Karyotypic analysis revealed the loss of a 6(q16;q22) deletion present in the parental line in all of the resistant lines. This portion of chromosome 6 has been shown to contain the gene for 5'nucleotidase. Early events in the transport and metabolism appear to be involved in the resistance mechanisms to nucleoside analogues and are responsible for broad cross resistance to this family of compounds.

Summary Objectives: Retrospective evaluation of anemia frequency and its prognostic value in patients with different subtypes of nonHodgkin's lymphoma and comparison with other clinical characteristics. Patients and methods: Anemia was defined as a hemoglobin value less than or equal to 12 g/dl for all men and women over 50 years of age, and less than or equal to 11 g/dl for women under 50 years of age. The study included 1077 adult lymphoma patients treated between 1980 and 1995 with the following histologic subtypes: 127 patients with small lymphocytic or lymphoplasmacytoid, 62 with marginal zone, 50 with mantlecell, 208 with follicular, 104 with T-cell lymphoma, 426 with diffuse large-cell and, finally, 73 patients with other high-grade lymphomas. Results: Anemia was present in 341 patients (32%). It was an adverse prognostic factor (P < 0.0001) for overall survival (OS) and progression-free survival (PFS) but not for relapsefree survival (RFS). When patients with and those without bone marrow involvement were considered separately, anemia remained an adverse factor. Anemia was significantly associated with shorter PFS in small lymphocytic or lymphoplasmacytoid, mantle cell, diffuse large cell and high-grade lymphomas and with shorter OS in all histologic subgroups except marginal zone lymphoma. In multivariate analysis, anemia was a significant prognostic factor for OS and PFS for the population as a whole (P = 0.0001 and P = 0.0048, respectively) and in patients with bone marrow involvement (P - 0.007 and P 0.005, respectively) but not in patients without bone marrow involvement. Finally, the addition of anemia to the International Prognostic Index led to an improvement for OS (P — 0.0004) and PFS (P = 0.0004). Conclusions: Anemia is an important adverse prognostic factor for the outcome of lymphoma patients, particularly in some histologic subgroups and in patients with bone marrow involvement.

Peripheral blood progenitor cells (PBPC) were mobilized and harvested in 200 patients treated for non-Hodgkin's lymphoma (n = 148), Hodgkin's disease (n = 22) and multiple myeloma (n = 30). The variables predicting the collection of a minimal (2.5 x 10(6)/kg) or a high (10 x 10(6)/kg) CD34+ cell count were analysed. Patients were mobilized with haemopoietic growth factors following either standard chemotherapy (n = 49) or high-dose cyclophosphamide, given alone (n = 55) or combined with high-dose VP16 (n = 86). 10 patients received haemopoietic growth factors only. The first mobilization resulted in a PBPC harvest with enough CD34+ cells in 179/200 patients (90%). High-dose cyclophosphamide, with or without VP16, did not mobilize a higher progenitor cell yield than standard chemotherapy. When performing multiple regression analysis in the 190 patients who received chemotherapy-containing mobilization, only the number of previous chemotherapy regimens and the exposure to fludarabine predicted for a failure to collect a minimal PBPC count (P=0.06 and 0.0008 respectively). The target to collect a high CD34+ cell count was negatively associated with the number of previous chemotherapy regimens (P=0.002). When only non-Hodgkin's lymphoma patients were considered for multivariate analysis, low-grade histology with fludarabine appeared to be associated with poor PBPC cell yield (P=0.08 and 0.005 respectively). This data confirms that PBPC harvest should be planned early in the disease course in transplant candidates, and can be obtained after a standard course of chemotherapy.

We analyzed the effect of high temperature (a 1-h incubation at 43 degrees C) on the accumulation and cytotoxicity of vinblastine and docetaxel in two model cell lines, K562 and MESSA, and their multidrug resistance (MDR) counterparts, K562/R7 and MESSA/Dx5. High temperature increased the amount of intracellular vinblastine and docetaxel significantly in MESSA cell and, to a much lesser extent, in K562 cells. MDR-positive cells retained a profound drug accumulation defect at 43 degrees C. Hyperthermia enhanced the cytotoxic effect of vinblastine (but not docetaxel) in both K562 and MESSA cells, but not in the MDR-positive variants. PSC833, a potent modulator of P-glycoprotein, induced high levels of drug accumulation in the two MDR-positive cell lines at both 37 degrees C and at 43 degrees C. PSC833 also significantly reduced the resistance levels of the two MDR-positive lines at both 37 degrees C and at 43 degrees C. The effect of hyperthermia on drug accumulation thus seems to depend on the cell line, whereas the effect on cytotoxicity depends on the type of compound. The MDR phenotype remains a therapeutic obstacle at 43 degrees C but is accessible to modulation.

Summary Background: Despite improved detection of mantle cell lymphoma (MCL), results of its treatment with conventional therapies remain disappointing and the survival rate poor. The role of high-dose chemotherapy has recently been investigated but no potential benefit has been clearly established. We report here our experience with MCL patients treated with intensive chemotherapy and autologous stem cell transplantation (ASCT). Patients and methods: Of the 16 MCL patients who received high-dose chemotherapy and ASCT beginning in 1989, six were treated in first-line and 10 in sensitive relapse. Twelve of 16 patients received regimens which included total body irradiation. All patients received peripheral blood stem cells (PBSC) with the exception of one, who underwent bone marrow transplantation. Results: Three patients died of toxic effects of treatment. Three months after transplant, seven achieved complete responses (CR) and two partial responses (PR), two were stable and two had progressed. With a median follow-up after transplant of 22 months, five of the six surviving patients were without progression, and three were in CR. The median times for event-free survival (EFS) and overall survival (OS) were, respectively, 249 and 317 days. The expected three-year EFS and OS were 24%. The median survival after diagnosis was only 29 months. None of the criteria appeared to be significantly associated with a better outcome, but first-line intensification and a short delay after initial diagnosis may be favorable. Conclusion: In this study we were not able to confirm the hypothetical benefit of high-dose chemotherapy and PBSC transplantation in mantle cell lymphoma, even though this approach may be promising in a subgroup of patient.

To assess the usefulness of quantification of infected cells (ICs) in BAL fluid for the diagnosis of ventilator-associated pneumonia (VAP).A prospective study.A medico-surgical ICU in a tertiary health-care institution.One hundred thirty-two patients (mean age, 52 +/- 19 years). The suspicion of nosocomial pneumonia was strong in these patients: all had fever (or = 38.5 degrees C), purulent tracheal aspirates, leukocytosis (or = 10,000 cells per cubic millimeter), and new or persistent radiographic lung infiltrates.One hundred sixty-three samples (BAL and protected specimen brushes [PSB]) were obtained.VAP was present in 56 cases. The diagnosis was excluded in the remaining 107 cases. The IC count was performed on 100 cells in BAL fluid. The percentage of IC was significantly higher (12.6 +/- 12.4 vs 1.14 +/- 3.39; p0.0001) in patients with pneumonia: the area under the receiver operating characteristic (ROC) curve was 0.888 and a threshold of 2% of IC corresponded to a sensitivity of 84%, a specificity of 80%, a positive predictive value of 69%, and a negative predictive value of 90%.It is possible to define a threshold of IC in BAL fluid with a good reliability by using an ROC curve. This technique is useful for the early diagnosis (2 h) of nosocomial bacterial pneumonia in mechanically ventilated patients and allows a rapid and appropriate treatment of most of the patients with suspected VAP.

A majority of tumor cell lines are considered to be "methionine-dependent" because of their inability to grow in culture when methionine is replaced by its precursor, homocysteine. We have previously shown that this phenotype is not due to the incapacity to synthesize methionine from homocysteine but rather to a deficiency in the "methionine salvage pathway", including 4-methylthio-2-oxobutanoic acid (MTOB), which is transaminated into methionine. At low concentrations MTOB can restore normal growth of methionine-dependent cell lines in the absence of methionine. However, when MTOB concentrations are increased the cells undergo apoptosis. Methional, a metabolite of MTOB produced by the branched-chain oxo acid dehydrogenase complex, is a potent inducer of apoptosis in a murine lymphoid cell line. We suggest that the methionine-dependent phenotype is associated with a reduced content of methional, which behaves as a proapoptotic agent. For this reason, methionine-dependent cells have a relative survival advantage.

Microtubules play an essential role in cell division. Little is known about possible variations of total tubulin and tubulin isotype expression during the cell cycle. We analyzed the total tubulin content, tubulin polymerization status and tubulin isotype content in resting and dividing human K562 leukemic cells and human MES-SA sarcoma cells. Although the total cellular tubulin content increases as the cells progress toward mitosis, the total tubulin/total protein ratio is stable during the cell cycle. Reverse transcriptase-polymerase chain reaction was applied to analyze the levels of expression of alpha, beta, and gamma-tubulin isotypes. Whereas alpha-tubulin isotype and gamma-tubulin transcripts were found to be expressed at constant levels throughout the cell cycle, some of the beta-tubulin isotype transcripts were found to be more highly expressed in dividing then in resting cells. Both of the class IV beta-tubulin isotype transcripts (human 5 beta and beta 2, Class IVa and IVb, respectively) were expressed in dividing K562 and MES-SA cells at twice the levels found in resting cells. Increased expression of the class IV isotype proteins in dividing cells was confirmed by immunoblotting, both in K562 and in MES-SA cells. A larger fraction of total cell tubulin was found to be polymerized in dividing cells (36-40%) than in resting cells (27-30%). The degree of polymerization of class IV tubulin in dividing and resting cells was similar to that of total tubulin. These results show that total tubulin is expressed as constant levels throughout the cell cycle but that the degree of polymerization is increased as cells are committed to division. The relative overexpression of the two class IV beta-tubulin isotypes in dividing cells suggests functional specificity for these isotypes and a regulatory role of these isotypes on the microtubule network during mitosis.

Various mechanisms can contribute to cellular resistance to doxorubicin. These include expression of the multidrug transporter P-glycoprotein (product of the mdr1 gene [also known as PGY1], Mrp (multidrug resistance-associated protein), the p110 major vault protein, altered glutathione metabolism, and altered levels or activity of topoisomerase II (Topo II). We reported recently that single-step treatment of human MES-SA sarcoma cells with 40 nM doxorubicin resulted in selection of spontaneous mutants at a rate of 1.8 x 10(-6) per cell generation. All individually selected mutants manifested the multidrug-resistant phenotype, related to activation of the mdr1 gene.Luria and Delbrück fluctuation analysis was performed with MES-SA cells to determine the mutation rate and the nature and mechanisms of resistance after single-step selection with doxorubicin in the presence of the cyclosporin PSC 833, a potent modulator of multidrug resistance.Ten flasks were seeded with 2000 cells/flask and grown to confluent populations of approximately 8 x 10(6) cells. After reseeding in 96-well plates, the populations were treated with 40 nM doxorubicin and 2 microM PSC 833 for 3 weeks. Surviving colonies were scored, individually harvested, and propagated. The drug-resistant phenotype was assessed by the tetrazolium dye (MTT) cytotoxicity assay and by monitoring cellular glutathione content and radiolabeled drug accumulation. Coupled reverse transcription-polymerase chain reaction (RT-PCR) was used to evaluate mdr1, MRP, Topo II alpha, and Topo II beta gene expression. Topo II, P-glycoprotein, and p110 levels were examined by immunoblotting or immunocytochemistry. Topo II activity was assessed by decatenation of kinetoplast DNA, and etoposide-induced cleavable complex formation was studied by the potassium-sodium dodecyl sulfate precipitation assay.Mutations were detected at a rate of 2.5 x 10(-7) per cell generation. Analysis of variance indicates that spontaneous mutations, rather than changes in cellular function, conferred resistance to doxorubicin and PSC 833. None of the isolated clones expressed mdr1 messenger RNA or P-glycoprotein, and none exhibited an increase in MRP expression. No alterations were found in cellular glutathione content, intracellular accumulations of daunorubicin and etoposide, levels of p110 protein, or levels of Topo II beta transcripts. However, a significant decrease in Topo II alpha messenger RNA and protein was found in all examined clones, as well as decreased Topo II catalytic activity and reduced cleavable complex formation in the presence of etoposide.PSC 833 co-selection reduced the mutation rate for doxorubicin-selected resistance by 10-fold and suppressed the emergence of mdr1 mutants. Survival of cells exposed to doxorubicin and PSC 833 occurs by selection of spontaneously arising mutants that exhibit altered Topo II alpha expression.Our results suggest that treatment with multidrug resistance modulators such as PSC 833 together with multidrug resistance-related cytotoxins may suppress the activation of mdr1 and prevent the emergence of resistant cancer cell clones with the multidrug-resistant phenotype.

4-Methylthio-2-oxobutanoic acid is the direct precursor of methional, which is a potent inducer of apoptosis in a BAF3 murine lymphoid cell line which is interleukin-3 (IL3)-dependent. Cultures treated for 8 h with methional in the presence of IL3 show extensive DNA double-strand breaks on flow cytometric analysis, increases in DNA fragmentation as measured by the amount of non-sedimentable DNA present in the 30,000 g supernatant of cell lysates and the typical laddering pattern of multiples of 180 bp seen upon agarose gel electrophoresis. No such features of apoptosis were found in cells treated with 4-methylthio 2-oxobutanoic acid or propanal, suggesting that the simultaneous presence of the methylthio group on the propanal moiety is essential for apoptosis to take place. Methional is further metabolized in cells by two reactions: oxidation via aldehyde dehydrogenase to (methylthio)propionic acid or beta-hydroxylation to malondialdehyde. The formation of malondialdehyde from methional in vitro by chemical hydroxylation under the conditions of the Fenton reaction provides a mechanism for the beta-hydroxylation which takes place in vivo. During apoptosis induced by IL3 deprivation, the ratio of 2,4-DNPH MDA to 2,4-DNPH methional is 0.94 in cells in IL3- medium compared with 0.54 in cells in IL3+ medium. These results support a role of cellular methional and malondialdehyde in apoptosis.

A paclitaxel-resistant cell line, KPTA5, was established by co-selecting the parental erythroleukemic cell line K562 with stepwise increased concentrations of paclitaxel (Taxol) in the presence of the cyclosporin D analogue PSC 833 (2 microM), a potent modulator of the multidrug resistance phenotype. KPTA5 cells are 9-fold resistant to paclitaxel and taxotere, but do not exhibit significant resistance to Vinca alkaloids, etoposide, anthracyclines, antimetabolites, or alkylating agents. Doubling time and morphology were similar to the parental K562 cells. Reverse transcriptase-polymerase chain reaction (rt-PCR) analysis revealed no alterations in the expression of the mdr1 and MRP genes. Cellular paclitaxel accumulation was unchanged. Cell cycle analyses showed that at 20 nM there was a significantly higher proportion of K562 cells blocked in G2/M, in comparison with KPTA5 cells. In both cases, disruption of the mitotic spindles and the presence of multiple mitotic asters were comparable but occurred at lower paclitaxel concentrations in K562 cells than in KPTA5 cells. There was no difference in total tubulin content between K562 and KPTA5 cells as analyzed by immunoblotting with an anti-beta-tubulin monoclonal antibody. However, we found that KPTA5 cells presented a 2-fold increase both in 5 beta-tubulin mRNA expression and in the corresponding tubulin protein Class IV isotype content, as evaluated by rt-PCR and immunostaining. In conclusion, the KPTA5 cell line displays a novel mechanism of resistance to paclitaxel which does not involve altered cellular drug accumulation. The data presented suggest that alterations in expression of the 5 beta-tubulin gene may be involved in paclitaxel resistance.

A 7 1/2-year-old patient with glycogenosis type Ib had chronic neutropenia, recurrent bacterial infections, and severe hypoglycemia in spite of continuous nasogastric feeding. She was treated with lenograstim (glycosylated recombinant human granulocyte colony-stimulating factor) and orthotopic liver transplantation. Absolute neutrophil counts and platelet counts rapidly reached normal values, and infectious episodes were reduced. She resumed oral feeding after transplantation and had no subsequent hypoglycemic episodes.

Peripheral blood stem cells (PBSC) from 15 patients with advanced non-Hodgkin's lymphoma (NHL), two patients with chronic lymphocytic leukemia, and two patients with myeloma were collected by continuous-flow leukapheresis after chemotherapy with MIV (mitoxantrone, ifosfamide, and etoposide, five patients) or high-dose cyclophosphamide (14 patients), followed by administration of GM-CSF. Sixteen patients (84%) had persistent marrow involvement at time of inclusion. Results were compared to those obtained in a control group of similar age and disease status in whom collection had been performed after MIV chemotherapy alone. The number of mononuclear cells, granulocyte-macrophage colony-forming units (CFU-GM), CD34+ cells were higher in GM-CSF treated patients with a lower mean number of leukapheresis (3.5 versus 6.4). Among the 19 patients harvested after chemotherapy plus GM-CSF, more progenitor cells were obtained in the cyclophosphamide group than in the MIV group. In all these patients except one, the number of mononuclear cells was sufficient to realize a transplantation. Seventeen patients received intensification with BEAM regimen (8 patients) or cyclophosphamide plus etoposide and total body irradiation (9 patients). Two patients failed to reconstitute correct hematopoiesis and three early toxic deaths occurred for a total of five procedure-related deaths. Nine of these 17 patients are in persistent complete remission with a median post-transplant follow-up of 18 months. Time to reach granulocyte and platelet recovery was not correlated with the number of mononuclear cells, CFU-GM, granulocyte-erythroid-macrophage-megakaryocyte colony-forming units (CFU-GEMM), CD34+ cells, and CD34+ CD33- cells but with the number of previous chemotherapy regimens. PBSC harvesting is achievable after chemotherapy plus GM-CSF in heavily pretreated patients with persistent marrow involvement. Moreover, these cells are able to reconstitute correct hematopoiesis after intensive treatment in these patients.

The role of drugs inhibiting viral replication in patients infected with HIV has been confirmed. Until now only dideoxynucleosides, which are reverse transcriptase inhibitors, have demonstrated antiviral activity in humans. A number of compounds acting on other steps of the viral cycle are currently being evaluated and clinical trials are being performed. Some investigators are attempting to inhibit the binding of viral particles to target cells and their penetration into these by acting on the interaction between HIV ant the CD4 molecule. Another approach consists in the characterization of enzymatic activities which are specific of HIV, other than reverse transcriptase, such as ribonuclease H, integrase or protease, in order to prepare specific inhibitors. Attempts are made to inhibit retroviral gene expression and production of viral particles in infected cells. The development of new nucleoside analogues and drugs with mechanisms of action and toxicities different from those of zidovudine should allow in the near future combination chemotherapy of HIV infection.

Two patients with previously treated CLL received autologous PBSC transplantation after total body irradiation and high-dose chemotherapy. Before intensification, a partial marrow response had been obtained in both patients, with disappearance of peripheral blood involvement as shown by immunophenotypic assessment using fludarabine. PBSC collection was performed after a single course of high-dose cyclophosphamide followed by GM-CSF administration. One patient failed to reconstitute normal hematopoiesis and died 3 months post-transplant. The other is in continuous complete remission 12 months after intensification. This strategy in young patients with poor prognosis CLL warrants further investigation.

One hundred patients with aggressive malignant lymphoma treated with the LNH-80 regimen were evaluated for long-term survival, late relapse and long-term sequelae. The LNH-80 regimen consisted of three intensive courses of adriamycin, cyclophosphamide, vindesine and bleomycin, followed by consolidation and final intensification, as previously described. Of the eighty-four patients who achieved CR after induction, fifty-two are alive in continuous complete remission with a median follow-up of 9.2 years. Twenty-nine CR patients (35%) relapsed. Sixty-six percent of the relapses occurred during the first 18 months following the end of treatment but late relapses were observed up to 7 years off-therapy. The fifty-two long-term responders were evaluated for their ability to resume work, sexual function, fertility and presence of long-term sequelae. Of the 41 patients who worked before diagnosis of their disease, 66% had resumed their normal jobs and 24% had retired. Sexual activity was considered to be satisfactory by 66% of the patients. Eleven of the 15 patients (73%) who wanted children had between one and three children. Seven patients (14%) were considered to have mild long-term sequelae but all long-term survivors reported having an acceptable quality of life. Five of the patients who reached CR (6%) had second neoplasias. The LNH-80 regimen allowed 52% of the patients to benefit from long-term disease-free survival with minor long-term toxicity.

The 100 patients with aggressive malignant non Hodgkin lymphoma treated with the LNH-80 regimen were evaluated for long-term survival and quality of life. The LNH-80 regimen consisted of three intensive courses of adriamycin, cyclophosphamide, vindesine and bleomycin, followed by consolidation and final intensification, as previously described. Of the eighty-four patients who achieved CR after induction, fifty-two patients are alive in continuous complete remission with a median follow-up of 9.2 years. Twenty-nine CR patients (35%) relapsed. Sixty-six percent of the relapses occurred during the first 18 months following the end of treatment but late relapses were observed up to 7 years off-therapy. Factors adversely correlated with response in multivariate analysis were poor performance status, bone marrow involvement and the presence of more than one extranodal site. Factors adversely correlated with survival were age, high grade subtypes, and bone marrow involvement. The fifty-two long-term responders were evaluated for quality of life parameters such as working ability, sexual function, fertility and absence of long-term sequelae. Of the 41 patients who worked before disease, 66% had resumed their normal job and 24% had retired. Sexual activity was considered to be satisfactory by 66% of the patients. Eleven of the 15 patients (73%) who wanted children had between one and three children. Seven patients (14%) considered having mild long-term sequelae but all long-term survivors reported having an acceptable quality of life. Five of the patients who reached CR (6%) had a second neoplasia. The LNH-80 regimen allowed 52% of the patients to benefit from long-term disease-free survival with minor long-term toxicity.

7526 Background: IFCT-0002 phase III trial compared two timings of CT in early lung cancer, all before surgery (PRE) versus PERIoperative, and two CT regimens, CDDP-Gem vs. CBDCA-Pac. 528 patients were randomized. Paraffin embedded post- chemo pathological specimens were collected in the 490 non complete responder patients for tissue expression of the putative biomarker beta-tubulin III (bTubIII). Methods: 423 surgical pathological specimens with enough remaining viable tumor tissue after neoadjuvant chemo were processed for immunohistochemistry as published in the Bio-IALT study. A semi-quantitative score was attributed taking account the number of stained cells and the intensity of staining. Semi-quantitative scores were studied as continuous variables, without any pre- determined cut-off. Multivariate analysis for progression-free (PFS) and overall survival (OS) were corrected with Bonferroni-Holm method for multiple analyses. Median follow-up was 42 months. Results: bTubIII was the only IHC marker significantly associated with poor PFS in univariate (p=0.014) or multivariate analysis, adjusted for histology, T and stage (HR= 1.50 [1.07–2.10]; p=0.020). In patients with a pathological specimen showing a bTubIII positive immunostaining, median PFS was 30.6 months, versus 60.1 months (HR=1.46 [1.08–1.99]) for bTubIII negative patients. bTubIII IHC score remained predictive of poor OS in univariate (p= 0.0065) as in multivariate analysis (p=0.019 with Bonferroni correction, HR=1.75 [1.15–2.68] ). Median OS was not reached for bTubIII negative patients whereas it was 71.7 months in patients with bTubIII immunostaining of any intensity score (HR=1.61, [1.11–2.35]). Conclusions: This study showed a dramatic negative prognostic impact for bTubIII immunostaining in resectable early lung cancer. A subset of bTubIII expressing patients with poor prognosis did not take any advantage from perioperative chemo. Hence, those patients could rather have beneficiated from personalized adjuvant treatment with alternative approaches. No significant financial relationships to disclose.

Gangliosides are glycosphingolipids which contain neuraminic acid. Although they are present in the plasma membranes of all cells, gangliosides are expressed differently, both quantitatively and qualitatively, in certain types of cancer. Modifications in ganglioside composition may account for some of the abnormal interactions between these tumor cells and their environment. Furthermore, some of the gangliosides are shed by tumor cells and may modify host immunity, thus contributing to the development of tumors. In cases of melanoma and neuroblastoma, the modifications in ganglioside expression are such that gangliosides may be used both as tumor markers and as targets for immunotherapy.