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BackgroundNeuroblastoma (NB) is a paediatric tumour of the sympathetic nervous system. Half of all cases are defined high-risk with an overall survival less than 40% at 5 years from diagnosis. The lack of in vitro models able to recapitulate the intrinsic heterogeneity of primary NB tumours has hindered progress in understanding disease pathogenesis and therapy response.MethodsHere we describe the establishment of 6 patient-derived organoids (PDOs) from cells of NB tumour biopsies capable of self-organising in a structure resembling the tissue of origin.ResultsPDOs recapitulate the histological architecture typical of the NB tumour. Moreover, PDOs expressed NB specific markers such as neural cell adhesion molecules, NB84 antigen, synaptophysin (SYP), chromogranin A (CHGA) and neural cell adhesion molecule NCAM (CD56). Analyses of whole genome genotyping array revealed that PDOs maintained patient-specific chromosomal aberrations such asMYCNamplification, deletion of 1p and gain of chromosome 17q. Furthermore, the PDOs showed stemness features and retained cellular heterogeneity reflecting the high heterogeneity of NB tumours.ConclusionsWe were able to create a novel preclinical model for NB exhibiting self-renewal property and allowing to obtain a reservoir of NB patients’ biological material useful for the study of NB molecular pathogenesis and to test drugs for personalised treatments.

Peripheral blood lymphoid cells of 29 patients with acute lymphocytic leukaemia (ALL) at onset were studied for characterization of B and T membrane markers and phytohaemagglutinin responsiveness. 24 cases (83%) were classified as "null" cell ALL and 5 (17%) as T-cell ALL. No relationship could be found between cytological presentation and immunological classification. Moreover, no correlation has been demonstrated between clinical-immunological parameters and prognosis, indicating that in our series of patients, assessment of cell size and surface markers were not a reliable predictor of prognosis.

Neuroblastoma is an extracranial solid tumor which occurs in infants and young children and accounts for 8% of pediatric cancers. It origins from neural crest cells of the sympathetic nervous system. Disease-free survival ranges from 95% for localized tumors to 30% for metastatic disease in children over 1 year of age and patients' outcome depends on dissemination and tissue histology. Despite the most recent therapies, the overall survival for high risk patients is still low and the outcome is invariably fatal. Improvement of neuroblastoma treatment is one of the highest priorities in pediatric oncology and a major challenge to clinicians and researchers. Understanding the biology and genetics of pediatric malignancies will be the key to identify molecular targets for innovative treatments as well as to individual management of disease. The success of human genome project and recent advances in technology have provided new tools to investigate cancer cells and to discover new tumor-associated genes. High-throughput efforts include array-based comparative genomic hybridization, single-nucleotide polymorphism arrays and expression microarrays. Here we present an overview on the most recent advances in wide-genome analysis of neuroblastoma. We also focus on the potential clinical application of genome and transcriptome information to the diagnosis, prognosis and neuroblastoma therapy.

We studied apoptosis in 36 neuroblastomas by DNA ladder assay. Expression of bcl2-α and β mRNA isoforms and protein were detected by RT-PCR and by immunohistochemistry, respectively. Internucleosomal DNA fragmentation was found in 20/36 (56%) tumor tissues collected both at onset and relapse of disease. Bcl-2α and β mRNAs and protein were found in almost all examined tumors irrespective of DNA ladder, thus showing lack of correlation with the clinical stage. BCL-2 protein was observed to be expressed at various levels in undifferentiated and in more differentiated neuroblasts, while the stroma and the fibrovascular tissue were negative. Our results show that apoptosis is present in neuroblastoma at all stages and that bcl-2 gene is widely expressed in tumor tissue. In our series of neuroblastomas, bcl-2 expression is not correlated with unfavorable prognosis.

Objectives Oral fields of visually normal and non-dysplastic mucosa (ODFs) may represent the precursors of oral potentially malignant lesions (OPMLs). Aim of the study was to provide new evidence for the concept of the “field carcinogenesis” model by comparing the ODF and OPML genomic aberration profiles obtained by high resolution DNA flow cytometry (hr DNA-FCM) and array-Comparative Genomic Hybridization (a-CGH). A second aim was to investigate if specific CGH aberrations were associated with DNA aneuploidy. Methods Nineteen patients with single OPMLs were recruited for the study. In parallel with obtaining samples of OPML tissue from 11 leukoplakias without dysplasia (nd-OPMLs) and 8 with dysplasia (d-OPMLs), we also obtained samples from distant ODFs. DNA aneuploid nuclei detected by hr DNA-FCM were physically separated, based on DNA content, from the DNA diploid components with a DNA-FCM-Sorter. These relatively pure subpopulations of epithelial nuclei were then submitted to DNA extraction and a-CGH for a genome-wide analysis of DNA copy number aberrations (CNAs). Results The frequencies of DNA aneuploidy (DI ≠ 1) among ODFs and OPMLs were respectively 5.3% and 32%. The DI aneuploid values of ODFs and nd-OPMLs were all near-diploid (DI ≠ 1 and DI ≤ 1.4), while for d-OPMLs were high-aneuploid (DI > 1.4) in 40% of the cases. CNA averages were 1.9 in ODFs and 6.5 in OPMLs. The gain of the chromosomal region 20q13.33-qter was observed in 37% of both ODFs and corresponding OPMLs. Additional common regions included 7p22.2-pter, 11p15.5-pter and 16p13.3-pter where gains were observed. Furthermore, gains of 20q13.31–q13.33 and of 5p13.33-pter and loss of 9p21.3 were detected at high frequency (respectively, at 62.5%, 50% and 50%) only in d-OPMLs. In particular, loss at 9p21.3, gain at 5p13.33-pter and gain of 20q13.31–q13.33 were associated with DNA aneuploidy (p = 0.00004; p = 0.0005; p = 0.01). Conclusions ODFs and OPMLs showed common CNAs in specific chromosomal regions suggesting that they may represent early events of the natural history of oral carcinogenesis according to the field effect cancerization and may contribute to the ODF-OPML transition. In addition, loss at 9p21.3 and gains at 5p13.33-pter and 20q13.31–q13.33 may contribute to DNA aneuploidization.

The expression of alpha, beta and gamma retinoic acid receptors (RAR) was analyzed by reverse transcription polymerase chain reaction (RT/PCR) in several neuroblastoma derived cell lines before and after exposure to 10 nM retinoic acid. Each cell line shows a different receptor pattern: RAR alpha mRNA is ubiquitously present, whereas RAR beta and RAR gamma mRNAs are not always expressed. After retinoic acid treatment at physiological concentration, the majority of cell lines shows expression of all three receptors but two are resistant to the retinoid in expressing RAR beta mRNA. These data suggest that each NB cell line follows a particular retinoic acid-dependent differentiation route, at least with regard to the expression of RAR alpha, beta and gamma receptors. In an attempt to develop a biochemical classification of neuroblastomas, which could also be useful in the prognosis of the disease, we have screened biopsies belonging to patients in different clinical stages for the distribution of RAR receptors. The results show that the pattern of RAR alpha, beta and gamma mRNAs expression is rather variable in fresh tumors even if they are classified at the same stage. This may account for heterogeneous tumor cell composition which has in turn its own complement of RA receptors.

The possible use of nanopores for single DNA molecules biosensing has been demonstrated, but much remains to do in order to develop advanced engineered devices with enhanced stability, and controlled geometry and surface properties. Here we present morphological and electrical characterization of solid state silicon nitride nanopores fabricated by focused ion beam direct milling and chemically functionalized by probe oligonucleotides, with the final aim of developing a versatile tool for biosensing and gene expression profiling.

Recently, nanopore technology has been introduced for genome analysis. Here we show results related to the possibility of preparing “engineered solid state nanopores”. The nanopores were fabricated on a suspended Si 3 N 4 membrane by Focused Ion Beam (FIB) drilling and chemically functionalized in order to covalently bind oligonucleotides (probes) on their surface. Our data show the stable effect of DNA attachment on the ionic current measured through the nanopore, making it possible to conceive and develop a selective biosensor for gene expression profiling.

Brn-3b transcription factor enhances proliferation of neuroblastoma (NB) and breast cancer cell lines in vitro and increases the rate and size of in vivo tumour growth, whereas reducing Brn-3b slows growth, both in vitro and in vivo. Brn-3b is elevated in >65% of breast cancer biopsies, and here we demonstrate that Brn-3b is also elevated in NB tumours. We show a significant correlation between Brn-3b and cyclin D1 (CD1) in breast cancers and NB tumours and cell lines. Brn-3b directly transactivates the CD1 promoter in co-transfection experiments, whereas electrophoretic mobility shift assay and chromatin immunoprecipitation assays demonstrate that Brn-3b protein binds to an octamer sequence located in the proximal CD1 promoter. Site-directed mutagenesis of this sequence resulted in loss of transactivation of the CD1 promoter by Brn-3b. Thus, Brn-3b may act to alter growth properties of breast cancer and NB cells by enhancing CD1 expression in these cells.

Neuroblastoma (NB) is the most common pediatric neuroendocrine tumor, and it is characterized by a quite variable clinical course. We previously found a great variability in the expression of somatostatin receptor type 2 (sst2) in several human NB cell lines and primary tumors. In this report we investigated whether expression of sst2 is somehow related to clinical outcome. We performed a retrospective study on 54 patients with a maximum follow-up of 100 months. The concentration of specific messenger ribonucleic acid (mRNA) for sst2 was measured by competitive RT-PCR and validated, in a small subset of samples, by quantitative imaging of gene (in situ hybridization) and protein (immunohistochemistry) expression. We found that sst2 mRNA was variably expressed in all NB tumors (range, 2.5 x 10(5) to 8 x 10(9) molecules/microg RNA) with a relevant reduction in the more advanced stage (P0.01). Analysis of Kaplan-Meier curves indicated that sst2 expression is positively related to the overall (P0.0001) and event-free (P0.0001) survival. Expression of sst2 was negatively related to tumor stage (P0.02) and MYCN amplification (P0.001), a poor prognostic factor. However, the prognostic information derived from sst2 is apparently independent from MYCN amplification, as assessed by stratifying sst2 values according to MYCN. In addition, the expression of sst2 was the only significant prognostic factor (P0.02) when it was included in a multivariate model containing other well known prognostic factors such as age, stage, and MYCN amplification. Hence, we propose that sst2 expression represents a new prognostic marker for NB. The main clinical value of a quantitative measure of sst2 lies in its ability to detect patients at low risk, independently from other prognostic factor, including MYCN amplification.

Rapid tumour progression in neuroblastoma is associated with MYCN amplification, deletion of the short arm of chromosome 1 and gain of 17q. However, patients with advanced disease without MYCN amplification and/or 1p deletion have a very poor outcome too, which suggests other genetic defects may predict an unfavourable prognosis. We employed CGH to study 22 tumours of patients at stages 3 and 4 over one year of age (6 and 16 cases respectively). Patients were divided in groups (A) long-term survivors and (B) short-term survivors. CGH showed a total of 226 chromosome imbalances (110 in group A and 116 in group B). The neuroblastoma cells of long-term survivors showed a preponderance of numerical aberrations (54%vs 43%); particularly gains of entire chromosomes 1 (P< 0.03), 7 (P< 0.04) and 19 (P< 0.05). An extra copy of 17 was detected in 6/8 (75%) samples of group A and only 1/14 (7%) samples of group B (P< 0.002). Conversely, tumours of patients who died from disease progression displayed a higher frequency of structural abnormalities (43%vs 35%), including loss of 1p, 9p, 11q, 15q and 18q and gain of 12q, although the difference was not significant (P= 0.24). Unbalanced gain of 17q was detected in 8/14 (57%) tumours of group B and only 1/8 (13%) tumours of group A (P< 0.05). The peculiar genetic difference observed in the tumours of long and short-term survivors may have prognostic relevance. © 2000 Cancer Research Campaign

The tp73 gene, a tp53 homologue, has been sub-regionally mapped at 1p36.3, a chromosomal region frequently deleted in neuroblastoma. Due to its chromosomal localization and to the mono-allelic expression observed in some neuroblastoma cell lines, it was proposed that tp73 might be involved in the pathogenesis of neuroblastoma. Functional assays have demonstrated that tp73 can inhibit cell proliferation and induce apoptosis. The role of this gene in tumorigenesis, however, is still unclear. We analyzed tp73 expression in 95 sporadic neuroblastoma samples by RT-PCR and we detected the tp73 transcript in 46 cases (48.4%), without significant correlation with age, clinical stage or 3-year overall survival. A genetic polymorphism in the 2nd exon of tp73 was utilized to identify the transcribed allele in tumor-cell samples. Expression from only one of the tp73 alleles was found in 13 out of 16 heterozygous tumors, while in 3 samples both alleles were present. Genotype analysis of 73 patients and 150 controls showed a significant deviation (p = 0.0308) from the Hardy-Weinberg equilibrium for a tp73 allele only among neuroblastoma patients. The absence of correlation between tp73 expression and clinical stage, age and survival suggests that this gene does not play an essential function in the clinical course of the disease. However, the distribution of genomic tp73 alleles in patients indicates that a role of this gene in the development of neuroblastoma cannot be completely ruled out. Int. J. Cancer (Pred. Oncol.) 84:365-369, 1999.

Deletion of chromosome 1p and MYCN amplification have been reported as frequent abnormalities in human neuroblastoma. We studied loss of heterozygosity (LOH) in 50 (48 informative) Italian neuroblastoma patients by restriction fragment length polymorphisms (RFLPs) analysis using anonymous and hypervariable region (HVR) sequences. Twelve cases (25%) showed LOH at one or more loci. Locus D1S94 was the most frequently involved in LOH events (8/12) of deleted cases (66.6%). MYCN amplification was observed in 20% of patients which showed a significantly lower event-free survival probability (EFSp) (P = 0.004). We also studied the allelic distribution in the constitutional DNA of neuroblastoma patients (n = 44) and a matched group of healthy Italian subjects (n = 79) for loci D1S112 and D1S94. A significantly (P = 0.01) different allele frequency was detected for the two groups at locus D1S94, but not at D1S112. Moreover, the neuroblastoma population did not confirm the Hardy-Weinberg expectations at the former locus. This observation suggests the existence of an allelotype associated with neuroblastoma susceptibility.

Loss of heterozygosity (LOH) and deletion of chromosome 1p are very often found in sporadic neuroblastoma. Nevertheless, very few data are available concerning 1p LOH in familial neuroblastoma. Families with recurrent neuroblastoma are rare and analysis of chromosome 1p in these families might give useful information for identifying the putative neuroblastoma suppressor gene. We used combined cytogenetic and molecular techniques to study 1p LOH in two neuroblastoma families. Family M has 2 out of 3 children with neuroblastoma and family C has 2 children, 1 of whom has neuroblastoma and type 1 neurofibromatosis (NF1). All patients of both families showed tumour cells with chromosome 1p deletion (1pdel), but only the patient from family C also had MYCN gene amplification. In all cases the deleted chromosome 1 was of maternal origin.

PURPOSE To evaluate the prognostic role of MYCN oncogene amplification in children with neuroblastoma. PATIENTS AND METHODS Of 694 children (age, 0 to 15 years) with previously untreated neuroblastoma, 295 (42%) were evaluated at diagnosis for MYCN gene amplification. RESULTS Clinical characteristics and survival results of 295 patients studied and 399 not studied for MYCN were comparable. In 48 of 295 patients studied for MYCN (16%), the gene was amplified (> or = three gene copies). Amplification was more frequent in children older than 1 year, with abdominal tumor (18% v 7%), advanced disease, normal vanillylmandelic (VMA) urinary excretion, and high lactate dehydrogenase (LDH), ferritin, and neuron-specific enolase (NSE) serum levels. In patients studied for MYCN, the 5-year overall survival (OS) rate was higher for children aged less than 1 year (90% v 44%), with extraabdominal tumor, stage 1 or 2 versus 3 versus 4, and normal NSE, LDH, and ferritin serum levels. Patients with amplified MYCN had a worse OS (odds ratio [OR], 3.38; confidence interval [CI], 2.22 to 5.16). This association held after adjustment for other characteristics. The impact of MYCN amplification was greater in patients with favorable characteristics, in particular age (OR, 10.28 for infants; 2.08 for older children) and stage (OR, 35.3 for stage 1 to 2; 8.41 for stage 3; 1.76 for stage 4). However, of 29 children with stage 4s, all three with amplified MYCN survive. In a multivariate analysis, the prognostic role of MYCN amplification, age, and stage was confirmed, but the size of the effect of MYCN was dependent on age and stage. CONCLUSION MYCN amplification is associated with a worse prognosis in children with neuroblastoma at all ages and stages except 4s. This association is most pronounced in children with otherwise favorable prognostic indicators, and in these children should be considered as an indication for more intensive intervention.

We present data concerning the electrical properties of a class of biosensor devices based on bio-functionalized solid state nanopores able to detect different kinds of interactions between probe molecules, chemically attached to the pore surface, and target molecules present in solution and electrophoretically drawn through the nanometric channel. The great potentiality of this approach resides in the fact that the functionalization of a quite large pore (up to 50-60 nm) allows a sufficient diameter reduction for the attainment of a single molecule sensing dimension and selective activation, without the need for further material deposition, such as metal or oxides, or localized surface modification. The results indicate that it will be possible, in the near future, to conceive and design devices for parallel analysis of biological samples made of arrays of nanopores differently functionalized, fabricated by standard lithographic techniques, with important applications in the field of molecular diagnosis.

Acquired resistance to doxorubicin and other anti-cancer drugs is generally dependent on gene amplification of a specific nucleotide sequence, the MDR1 gene. Verapamil, cyclosporin and other drugs have been used to circumvent the resistance in experimental models in vitro and/or in vivo. We have attempted to reverse the MDR phenotype by treating human adenocarcinoma resistant cells with 20 mers of synthetic unmodified oligodeoxynucleotide MDR1 antisenses. Five ODNs towards different mRNA regions and three different schedules of ODN antisense administration were tested. We found that FCS concentration greatly influenced the stability of ODN, whereas heat-inactivated FCS had no effect. The kinetics of ODN cellular uptake suggest the presence of a saturable receptor. Among the five antisense ODNs used, the most efficient was the oligomer (ODN-1) complementary to 20 bases upstream of the AUG initiation codon. No effect was observed with antisense complementary to the nucleotide binding sites. Administration of ODN-1 every 12 hr for 72 hr partially reversed the MDR phenotype. Approximately 60% of the cells lost their resistance to doxorubicin and did not form colonies in the presence of the drug. The MDR1 mRNA was transiently down-regulated so that the level of gp170 was slightly reduced. The incomplete switch off of MDR1 gene expression may be ascribed to the large abundance and great stability of MDR1 messenger RNA. Moreover, the inactivity of the two ODNs complementary to the NBS protein domains suggests that translation inhibition is ineffective. It is likely that ODN-4 and ODN-5 complement a large number of mRNAs competing for duplex formation, because these sequences are highly conserved among many proteins.

Calcyclin gene expression was evaluated in different neuroblastoma cell lines and during neuronal differentiation induced by retinoic acid. Calcyclin gene expression was more frequently detected in epithelial-type or Schwann-like cells rather than in neuroblastic cells. This result indicates an increase of G1 cell fraction, which may explain the limited growth potential usually observed for these cells. LAN-5 cell (neuronal type) differentiation experiments showed that calcyclin gene is detectable after 4 days of retinoic acid treatment, which induces G1 phase accumulation (as detected by cytofluorometric analysis), and cell growth arrest. Otherwise, neither block of cell proliferation by 0.5% fetal calf serum medium nor addition of 15% fresh fetal calf serum after cell arrest induce calcyclin expression. The increase of calcyclin mRNA levels during cell differentiation shows that calcyclin gene expression is associated with neuronal differentiation. This bivalent role of the calcyclin gene, which is normally expressed in the G1 phase of the cell cycle but also expressed during retinoic acid-induced neuroblastoma cell differentiation, suggests that (at least in neuroblastoma cells) the gene is subject to a complex transcriptional regulation.

Erythroid cell differentiation can be achieved in vitro by means of several chemical or natural agents. Cell differentiation is accompanied by biochemical and molecular changes which show that the inducer is active at different molecular levels. Among the chemical agents that are able to induce cell differentiation, the anticancer drugs are of great interest for the emerging study of in vitro and in vivo models for differentiation treatment. Cis-diamminedichloroplatinum II (CDDP), a crosslinking DNA compound, is usually employed at a high dosage in treating solid tumors. We have demonstrated that CDDP was also able to induce K562 cells towards erythroid differentiation. In our experiment 2.5 micrograms/ml of CDDP caused expression of alpha-globin chain gene and production of haemoglobulin. Continuous presence of the drug was not necessary to induce the cell to produce haemoglobin. Five days after CDDP treatment, the expression of c-myc oncogene had risen, while H3 histone mRNA expression fell to undetectable levels within 24 hours. Transferrin (Tf) receptor mRNA was reduced but later (about 48 hours) than c-myc and H3 messenger RNAs. The inhibition of cell proliferation was correlated both with the reduced expression of Tf receptor mRNA and low expression of the protein. However, expression of the cytoskeleton vimentin gene was only slightly affected during the time-course of the experiment. Data show that at least three phases were present in the irreversible CDDP induction of haemoglobin synthesis in the K562 cell. The erythroid differentiation was first preceded by a rise of c-myc mRNA, which probably precommits the cell towards the erythroid lineage. The mRNA levels of the cell-cycle dependent genes, H3 and Tf receptor, decreased and inhibition of DNA synthesis and loss of cell proliferation were detected. Finally, the alpha-globin chain gene was actively transcribed and the cell produced haemoglobin.

From an extended series neuroblastoma cases evaluated for MYCN amplification (MNA) at the "G. Gaslini" Hospital 15 (4 with and 11 without NMA) underwent myeloablative therapy and bone marrow transplantation (MAT-ABMT). Such cases ranged in age at diagnosis from 13 months to 7 years and were followed up at least 8 months after MAT-ABMT. MNA was present in 2/10 cases dead for disease, in 0/1 cases alive with disease, and in 2/4 cases presently in complete clinical remission. This preliminary evidence would discourage to consider MNA as a marker capable of predicting the final outcome of patients with metastatic Nb.

Thirty-four patients of an Italian population affected by neuroblastoma (NB) were evaluated at diagnosis for multidrug resistance gene (MDR1) and N-myc oncogene amplification. No patients showed MDR1 amplification, while extra copies of the N-myc gene were found in 9 out of 34 patients (26%). N-myc amplification was correlated (p = 0.008) with a shorter progression-free survival. RNA was purified from fresh tumor biopsies and analysed in 29 NB samples. MDR1 gene expression was found to be increased in 5 out of 29 tumor samples at onset (17%) and in 1 out of 3 at relapse, but none of them expressed both MDR1 and N-myc genes simultaneously. No correlation was found between MDR1 or N-myc genes expression and tumor progression. MDR1 mRNA transcription may occur spontaneously after onset, suggesting that certain NB tumors could be resistant to antineoplastic drugs at onset. All 5 patients showing MDR1 mRNA transcription achieved complete or partial clinical remission after polychemotherapy. This was presumably due to inclusion in the therapeutic protocol of a high dose of Cisplatin, a drug not susceptible to the effects of the MDR1 gene product. Our findings show that cells which actively transcribe for the MDR1 gene are present in several untreated NB patients. No gene amplification was detected and probably the MDR1 gene expression is regulated at the transcriptional level.

ZusammenfassungZwischen Januar 1984 und Dezember 1988 wurden 107 Neuroblastom (Nb)-Frischtumoren (inklusive 53 Patienten weniger als 1 Jahre alt zur Zeit der Diagnose) auf N-myc Amplifikation (NMA) untersucht. Zusatzlich wurde NMA mit u. a. folgenden fur die Prognose wichtigen biologischen und klinischen Variablen korreliert: Klinisches Stadium [1,2], histologisches Grading [3], urinare Ausscheidung von Vanillinmandelsaure (VMA) und Homovanillinsaure (HVA); Serumspiegel von Ferritin (Fer), neuronspezifische Enolase (NSE) und Laktatdehydrogenasen (LHD); und Volumen (Vol) des primaren Tumors. Diese Korrelationen wurden unter allen 107 Patienten und in der Sauglingsgruppe (Alter ≤ 1 Jahr) ausgewertet.N-myc war amplifiziert in 7/53

A phenotypically normal female, with negative family history for bleeding disorders, was found to be affected by severe haemophilia A. All laboratory tests performed confirmed the diagnosis. Chromosome analysis showed the presence of an X isochromosome of the long arm in every cell. It is hypothesized that the propositus inherited the affected X from her mother, a probable carrier, and the isochromosome, of paternal origin, was not able to mask the abnormal gene.

Neuroblastoma (NB) is a tumor usually arising in children and young adults showing different degrees of malignancy. Recently, the presence of N-myc amplification in neuroblasts has been associated with a poor outcome in the late stages of disease (Evans's Stage IV). Until now no amplification of N-myc gene has been observed in Stage IV-S, usually considered to have a favorable prognosis. In this paper we report a case of a child affected by NB Stage IV-S showing mild N-myc gene amplification. The finding of N-myc amplification in our patient shows that such alteration of the N-myc oncogene is not necessarily correlated with a poor prognosis; in this light the role of N-myc amplification in the neoplastic process should be reconsidered.

In the present study, 15 children with non-Hodgkin lymphoma have been immunologically evaluated by the following parameters on peripheral blood (PB) lymphocytes: phytohemagglutinin responsiveness (PHA-r); non-immune rosette formation with sheep red blood cells (RF-L) as T-cell marker; presence of surface immunoglobulins (sIg-L) as B-cell marker; serum immunoglobulins levels (IgA, IgM, IgG). Our patients (pts) have been divided in two groups: the first one includes 10 children without PB involvement; the second one includes 5 pts with bone-marrow and PB invasion. From our data it appears that: 1) the majority of pts of the first group presented normal values of membrane markers; PHA-r was impaired in 4/8 pts; 2) in pts with PB invasion absolute number of B and "null" cells was always abnormal and PHA-r altered; 3) in the second group of pts, a "null" cell origin can be suggested by the high percentage and absolute number of cells without surface markers. In our opinion, the high incidence of "null" cells represents the most relevant question: whether they are cells deprived of specific markers, or endowed with markers not identifiable by our current techniques, remains to be established.

The human leukemia cell line K562 expresses constitutively high levels of c-myc mRNA and can be induced to differentiate along the erythroid lineage. Treatment of K562 cells with the antineoplastic drugs 1-beta-D-arabinofuranosylcytosine and daunomycin causes differentiation into hemoglobin-producing cells. The differentiation process is associated with an early block of cellular proliferation occurring during the first 24 h of treatment. RNA synthesis is progressively reduced to 20 to 30% of the control levels after 3 days of exposure to the drugs. Dot and Northern blot analyses were performed to evaluate the levels of c-myc or globin mRNA during the differentiation of K562. Daunomycin and 1-beta-D-arabinofuranosylcytosine, despite their distinct chemical nature, induced similar modulation of mRNA levels. Globin mRNA did not change during the first 24 h of culture and began to increase after 48 h of treatment with drugs, reflecting the kinetic of appearance of hemoglobin-producing cells. In contrast, a transient decrease of c-myc mRNA was observed after the first 24 h of drug treatment, followed by a return to normal levels of c-myc mRNA after 48 h of treatment. Thus, the expression of c-myc mRNA in K562 did not reflect their proliferative activity nor their stage of differentiation. We speculate that the transient down-regulation of c-myc mRNA may be an initial event in the erythroid differentiation of K562.

Immunological characterization of lymphoid subpopulations has assumed an important role in the study of lymphoproliferative disorders, in the attempt to detect the nature of malignant cells and discover the possible relationship between malignancies and immunological status.

A new autosomally inherited dysfibrinogenaemia was recognized in 3 members of an Italian family. No bleeding tendency or thrombotic disease in any of the affected members were demonstrated. Coagulation tests revealed prolonged prothrombin, thrombin and Reptilase times. Plasma fibrinogen levels were normal with immunologic method and slightly reduced with chrono-metric assay: the other blood coagulation factors were normal. In addition, cross-immuno-electrophoresis performed on patients' plasma was indistinguishable from the normal. Dysfibrinogenaemia was confirmed by studying the purified fibrinogen. The fibrin polymerization curve, measured spectrophotometrically, showed a lower slope than the normal. A delay in fibrin monomer aggregation was revealed when compared to the normal at an equal concentration. The release of fibrinopeptides was normal. SDS polyacrylamide gel electrophoresis, isoelectric focusing and cross-immunoelectrophoresis of purified fibrinogen were not able to demonstrate any structural abnormality. The fibrinogen was named fibrinogen Genova.

N-myc oncogene is amplified in several human neuroblastoma cell lines and fresh neoplastic tissues; amplification would be highly correlated with advanced stages of neoplasia and associated with poor outcome of the disease. According to these data, N-myc amplification should be a new prognostic marker in addition to classical clinical and laboratory findings commonly monitored in neuroblastoma; some of them are levels of urinary Vanillylmandelic Acid (VMA) and Homovanillic Acid (HVA), serum Lactic Dehydrogenase (LDH) and serum Ferritin (sFe). We studied 4 patients in stage III and IV; N-myc amplification was detected in 2 cases in stage IV in primary tumor cells and in one case this finding was associated with high levels of serum Ferritin and LDH, while no correlation between other laboratory parameters and N-myc amplification has been found. We propose that N-myc amplification has to be evaluated with other prognostic factors to obtain useful information about the disease and the survival of the patient.

T (E+) lymphocytes purified from lymphoepithelial thymoma surgically removed from an asymptomatic 12 yrs old girl were cultured in presence of PHA-P; culture supernatant contained a T cell growth factor (IL-2) biochemically different from that purifiable from supernatants of normal T cells. Differences in molecular weight, isoelectric point and ion exchange elution pattern would allow to compare this abnormal IL-2, (named Thy-IL-2 from Thymus) to that already characterized from the HUT 102 T cell line (L-TCGF peak II). A comparison of biochemical properties of Thy-IL-2 and normal IL-2 (N-IL-2) is also presented; the biological significance of such differences are discussed.

In 22 patients with ALL in first complete remission, who discontinued therapy after 3 years, longitudinal follow-up of immunological reconstitution was investigated by assessing serum immunoglobulin levels, number and mitogen responsiveness of B and T lymphocytes. Major modifications have been demonstrated for T cells both in terms of number and functionality, while B cells and serum immunoglobulins did not change significantly. Examining the behaviour of the patients one by one, it has been observed that recovery is often characterized by a remarkable rebound occurring from the 15th to the 18th month. Immunosuppression induced by antileukemic treatment appeared to be a transitory phenomenon, mainly limited to the first three months. Reconstitution was achieved, in almost all cases, within one year after treatment was stopped.

The human erythroleukemia cell line K562 can be induced to erythroid terminal differentiation by several chemical agents. The property of inducing cellular differentiation in vitro has also been demonstrated for different antineoplastic agents commonly used in therapeutic protocols. The molecular events involved during erythroid differentiation are wholly unknown. Here we demonstrate that K562 cells, undergoing differentiation by the alkylating agent Cisplatin (cis-diamminedichloro platinum (II), CDDP) employed in clinical protocols for the treatment of solid tumors, are induced to produce haemoglobin. Down modulation of the transferrin receptor (Tfr), highly represented on the cell surface, is also observed during the early stages of differentiation. Furthermore, Tf receptor expression correlates with cell growth, is down regulated and lost during terminal differentiation. The Tfr down regulation is an early event, before haemoglobin production, during cell differentiation. The data suggest that CDDP can induce terminal differentiation in K562 cells in vitro, like other antineoplastic agents.

Six children suffering from Hodgkin's disease (HD), in different stages and free from chemo- and radiotherapy from at least four weeks, were treated with transfer factor (TF). PPD skin test, PHA-responsiveness, E-rosettes, B-lymphocytes were checked before TF therapy, after 6 and 9 TF doses and compared to the data at the onset of the disease. Two children with HD who did not receive TF, were examined as controls. PPD skin tests, PHA-responsiveness, E-rosettes did not ameliorate following TF treatment, while it has been noticed an increase in B-lymphocytes, both in percentage and absolute number. The Authors conclude that TF might have induced a slight B lymphoproliferation.

Fibrinogen Genova was recognized in an Italian family. The propositus had no bleeding tendency and diagnosis was performed on the basis of prolonged prothrombin, thrombin and reptilase times of plasma, associated with normal fibrinogen levels. The purified fibrinogen showed an inhibitory effect on the clotting times of the normal one.Functional studies performed on purified fibrinogen revealed that the clottability was reduced (74%, normal 88-94%) and the thrombin polymerization curve was abnormal due to a delayed fibrin monomers aggregation. The fibrino- peptides release was normal.Analysis of plasmic derivatives carried out by both SDS gel electrophoresis (5 and 9%) and immunological methods showed some differences compared with normal fibrinogen. The fibrinogen chains were studied on isoelectric focusing slabs and SDS gel electrophoresis. Preliminary results did not reveal any difference with normal.