Treatment of disseminated paraganglioma with gemcitabine and docetaxel

A male with metastatic paraganglioma received different chemotherapy regimens and 14 arterial embolizations with no or short-lasting clinical benefit. He was started on gemcitabine and docetaxel and, after two cycles, remission of all clinical signs occurred over 2 months. A complete biochemical response was achieved and angiographic signs of portal hypertension disappeared. He received 18 cycles of therapy and no limiting side effects were observed. More than 2 years after gemcitabine and docetaxel treatment, the patient remains symptom free. Gemcitabine and docetaxel could be a potential therapeutic strategy for this patient.

The calcium-sensing receptor and parathyroid hormone-related protein are expressed in differentiated, favorable neuroblastic tumors

BACKGROUND

Differentiated histopathology is a favorable prognostic factor in neuroblastic tumors, and molecular pathways underlying neuroblastoma differentiation can be modulated pharmacologically. The calcium-sensing receptor (CaR) and parathyroid hormone-related protein (PTHrP) regulate differentiation processes in some cellular contexts. CaR is up-regulated when neural stem cells are specified to the oligodendrocyte lineage and regulates PTHrP production in astrocytes. The objective of the current study was to assess whether CaR and PTHrP participate in neuroblastoma differentiation pathways.

METHODS

CaR and PTHrP messenger RNA (mRNA) and protein expression were analyzed in neuroblastic tumors, and correlation with prognostic factors was assessed. CaR and PTHrP expression levels were analyzed in neuroblastoma cell lines treated with all-trans-retinoic acid or 5-bromo-2'-deoxyuridine (BrdU).

RESULTS

CaR expression was correlated with favorable histology, age at diagnosis <1 year, low clinical stage, and low clinical risk. CaR was absent in undifferentiated neuroblasts and was expressed in differentiating neuroblasts. CaR and PTHrP were highly expressed in ganglion and in Schwann-like cells. PTHrP mRNA levels were higher in ganglioneuroblastomas and ganglioneuromas than in neuroblastomas (P < .0001). Both genes were up-regulated in neuroblastomas with treatment-induced maturation features. CaR, but not PTHrP, was up-regulated at early phases of in vitro neuronal differentiation induction. Substrate-adherent, non-neuronal cell lines displayed the highest PTHrP levels among the neuroblastoma cell lines examined. The up-regulation of PTHrP and of 2 glial differentiation markers was observed in 2 cell lines that were treated with BrdU, whereas CaR was induced in only 1 cell line.

CONCLUSIONS

CaR and PTHrP were expressed in differentiated, favorable neuroblastic tumors, and both genes were up-regulated by inducing differentiation.

Comprehensive characterization of neuroblastoma cell line subtypes reveals bilineage potential similar to neural crest stem cells

Background

Neuroblastic tumors (NBT) derive from neural crest stem cells (NCSC). Histologically, NBT are composed by neuroblasts and Schwannian cells. In culture, neuroblastic (N-), substrate-adherent (S-) and intermediate phenotype (I-) cell subtypes arise spontaneously.

Methods

Here, neuroblastoma (NB) cell line subtypes were characterized according to embryonic peripheral nervous system development markers (GAP43, Phox2b, Sox10, c-kit, GD2, NF68, vimentin, S100β, calcyclin and ABCG2), morphological features, gene expression and differentiation potential. I-type cells were investigated as a bipotential (neuronal and glial) differentiation stage.

Results

Positive immunostaining of NCSC (GAP43, c-kit, NF68, vimentin and Phox2b) and undifferentiated cell (ABCG2) markers was observed in all NB subtypes. N- and I-type cells displayed cytoplasmic membrane GD2 staining, while nuclear calcyclin was restricted to S-type. N- and I-type cells showed similar phenotype and immunoreactivity pattern. Differential gene expression was associated with each cell subtype. N- and I-type cells displayed similar differentiation capacity towards neuronal and glial lineage fates. S-type cells, upon induction, did not show a neuronal-like phenotype, despite gene expression changes.

Conclusion

Results suggest that N- and I-type NB cell subtypes represent an immature bilineage stage, able to progress towards neuronal and glial fates upon induction of differentiation. S-type cells appear irreversibly committed to a glial lineage fate.

Primary Ewing sarcoma of the tentorium presenting with intracranial hemorrhage in a child

Spontaneous intracerebral hemorrhage in children is usually related to cerebrovascular conditions. Brain tumors presenting with spontaneous bleeding account for approximately 10% of intracranial hemorrhages in children. The occurrence of primitive central nervous system lesions in the Ewing sarcoma family of tumors (ESFT) not related to bone or metastatic disease is a rare condition. The authors report on a child who presented with intracranial bleeding secondary to a nonmetastatic tentorial ESFT confirmed by detection of the fusion gene EWS-ERG. A detailed review of the literature reveals that most primary intracranial ESFT had a meningeal attachment, and that almost half of them presented at diagnosis with hemorrhage. Distinguishing between ESFT and other intracranial neoplasms is essential because the treatment and prognosis differ remarkably from that of other tumors, namely central primitive neuroectodermal tumors (PNETs). Whereas adjuvant treatment for ESFT consists of local or regional radiotherapy and chemotherapy containing alkylating agents, central PNETs are generally treated with whole neuraxis radiation and platinum-based chemotherapy. Additionally, the prognosis for intracranial ESFT might be better than the one for nonpineal central PNETs.

Specific gene expression profiles and chromosomal abnormalities are associated with infant disseminated neuroblastoma

Background

Neuroblastoma (NB) tumours have the highest incidence of spontaneous remission, especially among the stage 4s NB subgroup affecting infants. Clinical distinction of stage 4s from lethal stage 4 can be difficult, but critical for therapeutic decisions. The aim of this study was to investigate chromosomal alterations and differential gene expression amongst infant disseminated NB subgroups.

Methods

Thirty-five NB tumours from patients diagnosed at < 18 months (25 stage 4 and 10 stage 4s), were evaluated by allelic and gene expression analyses.

Results

All stage 4s patients underwent spontaneous remission, only 48% stage 4 patients survived despite combined modality therapy. Stage 4 tumours were 90% near-diploid/tetraploid, 44% MYCN amplified, 77% had 1p LOH (50% 1p36), 23% 11q and/or 14q LOH (27%) and 47% had 17q gain. Stage 4s were 90% near-triploid, none MYCN amplified and LOH was restricted to 11q. Initial comparison analyses between stage 4s and 4 < 12 months tumours revealed distinct gene expression profiles. A significant portion of genes mapped to chromosome 1 (P < 0.0001), 90% with higher expression in stage 4s, and chromosome 11 (P = 0.0054), 91% with higher expression in stage 4. Less definite expression profiles were observed between stage 4s and 4 < 18m, yet, association with chromosomes 1 (P < 0.0001) and 11 (P = 0.005) was maintained. Distinct gene expression profiles but no significant association with specific chromosomal region localization was observed between stage 4s and stage 4 < 18 months without MYCN amplification.

Conclusion

Specific chromosomal aberrations are associated with distinct gene expression profiles which characterize spontaneously regressing or aggressive infant NB, providing the biological basis for the distinct clinical behaviour.

Differential expression of genes mapping to recurrently abnormal chromosomal regions characterize neuroblastic tumours with distinct ploidy status

Background

Neuroblastic tumours (NBTs) represent a heterogeneous spectrum of neoplastic diseases associated with multiple genetic alterations. Structural and numerical chromosomal changes are frequent and are predictive parameters of NBTs outcome. We performed a comparative analysis of the biological entities constituted by NBTs with different ploidy status.

Methods

Gene expression profiling of 49 diagnostic primary NBTs with ploidy data was performed using oligonucleotide microarray. Further analyses using Quantitative Real-Time Polymerase Chain Reaction (Q-PCR); array-Comparative Genomic Hybridization (aCGH); and Fluorescent in situ Hybridization (FISH) were performed to investigate the correlation between aneuploidy, chromosomal changes and gene expression profiles.

Results

Gene expression profiling of 49 primary near-triploid and near-diploid/tetraploid NBTs revealed distinct expression profiles associated with each NBT subgroup. A statistically significant portion of genes mapped to 1p36 (P = 0.01) and 17p13-q21 (P < 0.0001), described as recurrently altered in NBTs. Over 90% of these genes showed higher expression in near-triploid NBTs and the majority are involved in cell differentiation pathways. Specific chromosomal abnormalities observed in NBTs, 1p loss, 17q and whole chromosome 17 gains, were reflected in the gene expression profiles. Comparison between gene copy number and expression levels suggests that differential expression might be only partly dependent on gene copy number. Intratumoural clonal heterogeneity was observed in all NBTs, with marked interclonal variability in near-diploid/tetraploid tumours.

Conclusion

NBTs with different cellular DNA content display distinct transcriptional profiles with a significant portion of differentially expressed genes mapping to specific chromosomal regions known to be associated with outcome. Furthermore, our results demonstrate that these specific genetic abnormalities are highly heterogeneous in all NBTs, and suggest that NBTs with different ploidy status may result from different mechanisms of aneuploidy driving tumourigenesis.

Different CTNNB1 mutations as molecular genetic proof for the independent origin of four Wilms tumours in a patient with a novel germ line WT1 mutation

We describe a patient with a novel WT1 pS50X germ line mutation, who developed bilateral Wilms tumours, both with stromal-type histology. Both tumours showed loss of the wild type WT1 allele (loss of heterozygosity (LOH)) and a tumour specific mutation in catenin beta1 (CTNNB1), S45P in the left and Delta45S in the right tumour. Molecular analysis of microdissected cells from the left tumour revealed the same S45P CTNNB1 mutation in blastema, tubuli, stroma and muscle, and a different CTNNB1 mutation (T41A) in stromal cells isolated from another area of the same slide. Microdissection of two areas of muscle cells from the right tumour revealed the same Delta45S mutation and no CTNNB1 mutation nor LOH of WT1 in normal kidney cells. One year later, the patient developed a new set of bilateral tumours. Both tumours showed LOH of the wild type WT1 allele, but different CTNNB1 mutations as in the first tumours: S45C on the right and S45F on the left side, demonstrating that these developed independently and are not relapses. This case demonstrates the high risk for the development of Wilms tumours in patients with germ line truncation mutations.

Comprehensive analysis of tumoral DNA content reveals clonal ploidy heterogeneity as a marker with prognostic significance in locoregional neuroblastoma

The clinical management of locoregional neuroblastoma (LR NB) is controversial. In a previous study we showed that diploidy was a strong prognostic predictor of outcome and detected the existence of clonal ploidy heterogeneity in a select group of cases. The aims of this study were (1) to assess the frequency of ploidy heterogeneity in LR NB, (2) to ascertain the best method to detect heteterogeneity, and (3) to correlate ploidy populations with clinical outcome. We undertook a comprehensive analysis of tumoral DNA content in 38 LR NBs comparing (1) flow cytometry (FCM), (2) karyotyping, (3) interphase fluorescence in situ hybridization, and (4) laser-scanning cytometry (LSC). Tumor ploidy heterogeneity was found by all methodologies. By FCM, all tumors with aneuploid peaks had detectable diploid DNA peaks. By LSC, all tumors with diploid and hyperploid peaks were GD2-positive in both, consistent with their tumoral origin. A predominant near-triploid clonal population (ratio diploid vs. triploid, <2.5) was observed in most nonprogressing LR NB tumors, and a predominant diploid clone (ratio di- vs. triploid, >2.5) in most progressing LR NB cases. Multivariate analysis was performed to evaluate the prognostic value of tumor ploidy assayed by different methods versus age, INSS (International Neuroblastoma Staging System) stage, and MYCN status. FCM was the most powerful prognostic factor related to poor prognosis (overall survival, P = 0.02; progression-free survival, P = 0.01). These results provide strong evidence for clonal ploidy heterogeneity in LR NB and clonal evolution toward diploidy in progressing LR NB.

Epithelioid sarcoma with SYT-SSX1 fusion gene expression: molecular and cytogenetic analysis

Epithelioid sarcoma is a rare malignant soft tissue tumor of unknown histogenesis, characterized by the epithelioid morphology of tumor cells and co-expression of epithelial and mesenchymal lineage proteins. A common epithelial and mesenchymal immunophenotype is also found in another soft tissue tumor, the biphasic subtype of synovial sarcoma. Furthermore, the presence of a breakpoint at 18q11 in epithelioid sarcoma, similar to that found in synovial sarcoma, has been reported. These facts would support the hypothesis that both tumors may share a common histogenetic background. However, expression of the SYT-SSX fusion genes has been investigated in epithelioid sarcoma with negative results. We report, to our knowledge, the first epithelioid sarcoma in which the presence of SYT-SSX1 fusion gene has been detected by means of conventional RT-PCR analysis and sequencing, real-time RT-PCR and FISH. The SYT-SSX1 gene fusion was identified in a small proportion of tumoral cells. This finding supports a likely common histogenetic background for both epithelioid sarcoma and synovial sarcoma.

Naturally occurring cell death during postnatal development of rat skeletal muscle

Naturally occurring cell death has been extensively analyzed in many tissues, but little data exist regarding its occurrence in developing skeletal muscle. We investigated its occurrence and time course in rat hindlimb skeletal muscles during the first 3 weeks of postnatal development, its morphological and biochemical features, and the concomitant expression of Bax, Bcl-2, and Bcl-x(L). Myofibers displaying morphological features of apoptosis were found during the first 9 postnatal days. Terminal transferase (TdT)-mediated dUTP-biotinylated nick end labeling (TUNEL)-positive nuclei were present at all days examined and peaked between postnatal days 5 and 7. Total genomic DNA extracted from muscles at postnatal days 5, 7, and 9 showed internucleosomal fragmentation after Southern hybridization. Constitutive levels of Bax, Bcl-2, and Bcl-x(L) were detected by means of reverse transcriptase-polymerase chain reaction (RT-PCR) analysis at all ages examined, with a moderate increase around the period of maximal apoptosis. The results show that apoptosis and a concurrent expression of some genes of the Bcl-2 family, occur postnatally in rat skeletal muscle. This information is relevant to studies addressing the mechanisms of developmental muscle injuries.