Paired Primary and Recurrent Rhabdoid Meningiomas: Cytogenetic Alterations, BAP1 Gene Expression Profile and Patient Outcome

Rhabdoid meningiomas (RM) are a rare meningioma subtype with a heterogeneous clinical course which is more frequently associated with recurrence, even among tumors undergoing-complete surgical removal. Here, we retrospectively analyzed the clinical-histopathological and cytogenetic features of 29 tumors, from patients with recurrent (seven primary and 14 recurrent tumors) vs. non-recurrent RM (n = 8). Recurrent RM showed one (29%), two (29%) or three (42%) recurrences. BAP1 loss of expression was found in one third of all RM at diagnosis and increased to 100% in subsequent tumor recurrences. Despite both recurrent and non-recurrent RM shared chromosome 22 losses, non-recurrent tumors more frequently displayed extensive losses of chromosome 19p (62%) and/or 19q (50%), together with gains of chromosomes 20 and 21 (38%, respectively), whereas recurrent RM (at diagnosis) displayed more complex genotypic profiles with extensive losses of chromosomes 1p, 14q, 18p, 18q (67% each) and 21p (50%), together with focal gains at chromosome 17q22 (67%). Compared to paired primary tumors, recurrent RM samples revealed additional losses at chromosomes 16q and 19p (50% each), together with gains at chromosomes 1q and 17q in most recurrent tumors (67%, each). All deceased recurrent RM patients corresponded to women with chromosome 17q gains, although no statistical significant differences were found vs. the other RM patients.

The importance of considering competing risks in recurrence analysis of intracranial meningioma

BACKGROUND

The risk of recurrence is overestimated by the Kaplan-Meier method when competing events, such as death without recurrence, are present. Such overestimation can be avoided by using the Aalen-Johansen method, which is a direct extension of Kaplan-Meier that accounts for competing events. Meningiomas commonly occur in older individuals and have slow-growing properties, thereby warranting competing risk analysis. The extent to which competing events are considered in meningioma literature is unknown, and the consequences of using incorrect methodologies in meningioma recurrence risk analysis have not been investigated.

METHODS

We surveyed articles indexed on PubMed since 2020 to assess the usage of competing risk analysis in recent meningioma literature. To compare recurrence risk estimates obtained through Kaplan-Meier and Aalen-Johansen methods, we applied our international database comprising ~ 8,000 patients with a primary meningioma collected from 42 institutions.

RESULTS

Of 513 articles, 169 were eligible for full-text screening. There were 6,537 eligible cases from our PERNS database. The discrepancy between the results obtained by Kaplan-Meier and Aalen-Johansen was negligible among low-grade lesions and younger individuals. The discrepancy increased substantially in the patient groups associated with higher rates of competing events (older patients with high-grade lesions).

CONCLUSION

The importance of considering competing events in recurrence risk analysis is poorly recognized as only 6% of the studies we surveyed employed Aalen-Johansen analyses. Consequently, most of the previous literature has overestimated the risk of recurrence. The overestimation was negligible for studies involving low-grade lesions in younger individuals; however, overestimation might have been substantial for studies on high-grade lesions.

Clinical, Histopathologic and Genetic Features of Rhabdoid Meningiomas

Rhabdoid meningiomas (RM) shows heterogeneous histological findings, and a wide variety of chromosomal copy number alterations (CNA) are associated with an unpredictable course of the disease. In this study, we analyzed a series of 305 RM samples from patients previously reported in the literature and 33 samples from 23 patients studied in our laboratory. Monosomy 22-involving the minimal but most common recurrent region loss of the 22q11.23 chromosomal region was the most observed chromosomal alteration, followed by losses of chromosomes 14, 1, 6, and 19, polysomies of chromosomes 17, 1q, and 20, and gains of 13q14.2, 10p13, and 21q21.2 chromosomal regions. Based on their CNA profile, RM could be classified into two genetic subgroups with distinct clinicopathologic features characterized by the presence of (1) chromosomal losses only and (2) combined losses and gains of several chromosomes. The latter displays a higher frequency of WHO grade 3 tumors and poorer clinical outcomes.

Whole-Exome Sequencing Reveals Recurrent but Heterogeneous Mutational Profiles in Sporadic WHO Grade 1 Meningiomas

Human WHO grade 1 meningiomas are generally considered benign tumors; despite this, they account for ≈50% of all recurrent meningiomas. Currently, limited data exist about the mutational profiles of grade 1 meningiomas and patient outcome. We investigated the genetic variants present in 32 WHO grade 1 meningiomas using whole exome sequencing, and correlated gene mutational profiles with tumor cytogenetics and patient outcome. Overall, WHO grade 1 meningiomas harbored numerous and heterogeneous genetic variants, which most frequently affected the NF2 (47%) gene and to a less extent the PNMA6A (22%), TIGD1 (16%), SMO (13%), PTEN (13%), CREG2 (9%), EEF1A1 (6%), POLR2A (6%), ARID1B (3%), and FAIM3 (3%) genes. Notably, non-synonymous genetic variants of SMO and POLR2A were restricted to diploid meningiomas, whereas NF2 mutations were only found among tumors that showed -22/22q^─ (with or without a complex karyotype). Based on NF2 mutations and tumor cytogenetics, four genetic profiles were defined with an impact on patient recurrence-free survival (RFS). These included (1) two good-prognosis tumor subgroups-diploid meningiomas (n=9) and isolated -22/22q^─ associated with NF2 mutation (n=7)-with RFS rates at 10 y of 100%; and (2) two subgroups of poor-prognosis meningiomas-isolated -22/22q^─ without NF2 mutation (n=3) and tumors with complex karyotypes (n=11)-with a RFS rate at 10 y of 48% (p=0.003). Our results point out the existence of recurrent but heterogeneous mutational profiles in WHO grade 1 meningiomas which have an impact on patient outcome.

Tumor cell and immune cell profiles in primary human glioblastoma: Impact on patient outcome

The distribution and role of tumor-infiltrating leucocytes in glioblastoma (GBM) remain largely unknown. Here, we investigated the cellular composition of 55 primary (adult) GBM samples by flow cytometry and correlated the tumor immune profile with patient features at diagnosis and outcome. GBM single-cell suspensions were stained at diagnosis (n = 44) and recurrence following radiotherapy and chemotherapy (n = 11) with a panel of 8-color monoclonal antibody combinations for the identification and enumeration of (GFAP+ CD45- ) tumor and normal astrocytic cells, infiltrating myeloid cells -i.e. microglial and blood-derived tumor-associated macrophages (TAM), M1-like, and M2-like TAM, neutrophils. and myeloid-derived suppressor cells (MDSC)- and tumor-infiltrating lymphocytes (TIL) -i.e. CD3+ T-cells and their TCD4+ , TCD8+ , TCD4- CD8- , and (CD25+ CD127lo ) regulatory (T-regs) subsets, (CD19+ CD20+ ) B-cells, and (CD16+ ) NK-cells-. Overall, GBM samples consisted of a major population (mean ± 1SD) of tumor and normal astrocytic cells (73% ± 16%) together with a significant but variable fraction of immune cells (24% ± 18%). Within myeloid cells, TAM predominated (13% ± 12%) including both microglial cells (10% ± 11%) and blood-derived macrophages (3% ± 5%), in addition to a smaller proportion of neutrophils (5% ± 9%) and MDSC (4% ± 8%). Lymphocytes were less represented and mostly included TCD4+ (0.5% ± 0.7%) and TCD8+ cells (0.6% ± 0.7%), together with lower numbers of TCD4- CD8- T-cells (0.2% ± 0.4%), T-regs (0.1% ± 0.2%), B-lymphocytes (0.1% ± 0.2%) and NK-cells (0.05% ± 0.05%). Overall, three distinct immune profiles were identified: cases with a minor fraction of leucocytes, tumors with a predominance of TAM and neutrophils, and cases with mixed infiltration by TAM, neutrophils, and T-lymphocytes. Untreated GBM patients with mixed myeloid and lymphoid immune infiltrates showed a significantly shorter patient overall survival versus the other two groups, in the absence of gains of the EGFR gene (p = 0.02). Here we show that immune cell infiltrates are systematically present in GBM, with highly variable levels and immune profiles. Patients with mixed myeloid and T-lymphoid infiltrates showed a worse outcome.

Heterogeneous EGFR, CDK4, MDM4, and PDGFRA Gene Expression Profiles in Primary GBM: No Association with Patient Survival

BACKGROUND

The prognostic impact of the expression profile of genes recurrently amplified in glioblastoma multiforme (GBM) remains controversial.

METHODS

We investigated the RNA gene expression profile of epidermal growth factor receptor (EGFR), cyclin-dependent kinase 4 (CDK4), murine doble minute 4 (MDM4), and platelet derived growth factor receptor alpha (PDGFRA) in 83 primary GBM tumors vs. 42 normal brain tissue samples. Interphase FISH (iFISH) analysis for the four genes, together with analysis of intragenic deletions in EGFR and PDGFRA, were evaluated in parallel at the DNA level. As validation cohort, publicly available RNA gene expression data on 293 samples from 10 different GBM patient series were also studied.

RESULTS

At the RNA level, CDK4 was the most frequently overexpressed gene (90%) followed by EGFR (58%) and PDGFRA (58%). Chromosome 7 copy number alterations, i.e., trisomy (49%) and polysomy (44%), showed no clear association with EGFR gene expression levels. In turn, intragenic EGFR deletions were found in 39 patients (47%), including EGFRvIII (46%) in association with EGFRvIVa (4%), EGFRvII (2%) or other EGFR deletions (3%) and PDGFRA deletion of exons 8-9 was found in only two tumors (2%).

CONCLUSIONS

Overall, none of the gene expression profiles and/or intragenic EGFR deletions showed a significant impact on overall survival of GBM supporting the notion that other still unraveled features of the disease might play a more relevant prognostic role in GBM.

Prognostic stratification of adult primary glioblastoma multiforme patients based on their tumor gene amplification profiles

Several classification systems have been proposed to address genomic heterogeneity of glioblastoma multiforme, but they either showed limited prognostic value and/or are difficult to implement in routine diagnostics. Here we propose a prognostic stratification model for these primary tumors based on tumor gene amplification profiles, that might be easily implemented in routine diagnostics, and potentially improve the patients management. Gene amplification profiles were prospectively evaluated in 80 primary glioblastoma multiforme tumors using single-nucleotide polymorphism arrays and the results obtained validated in publicly available data from 267/347 cases. Gene amplification was detected in 45% of patients, and chromosome 7p11.2 including the EGFR gene, was the most frequently amplified chromosomal region – either alone (18%) or in combination with amplification of DNA sequences in other chromosomal regions (10% of cases). Other frequently amplified DNA sequences included regions in chromosomes 12q(10%), 4q12(7%) and 1q32.1(4%). Based on their gene amplification profiles, glioblastomas were subdivided into: i) tumors with no gene amplification (55%); ii) tumors with chromosome 7p/EGFR gene amplification (with or without amplification of other chromosomal regions) (38%); and iii) glioblastoma multiforme with a single (11%) or multiple (6%) amplified DNA sequences in chromosomal regions other than chromosome 7p. From the prognostic point of view, these amplification profiles showed a significant impact on overall survival of glioblastoma multiforme patients (p>0.001). Based on these gene amplification profiles, a risk-stratification scoring system was built for prognostic stratification of glioblastoma which might be easily implemented in routine diagnostics, and potentially contribute to improved patient management.

[Relevance of Simpson's grading system for resections in WHO grade I meningiomas]

OBJECT

The aim of this study is to assess if the recurrence rates and recurrence/progression-free survivals (RFS) are different after Simpson's grades I, II, III and IV resections in World Health Organization (WHO) grade I meningiomas.

MATERIAL AND METHODS

A retrospective review was conducted on the data of patients who underwent surgical treatment of WHO grade I meningiomas located in convexity, falx/parasagittal, and skull base (anterior/media/posterior) between June 1991 and December 2011. In Simpson's grade IV resections, surgical treatment was supplemented with radiotherapy/radiosurgery on the tumour remains. A comparison was made on the recurrence rates and RFSs between Simpson's grades I, II, III, and IV resections, both overall and in tumour subsets according to their location.

RESULTS

A total of 208 meningiomas were included in this study. There were no significant differences in recurrence rates and RFSs between Simpson's grades I, II, III, and IV. No significant differences were noted between the different degrees of Simpson in any of the location groups. In convexity meningiomas, the recurrence rates were 7% and 33% in Simpson's grades I and III resections, respectively (P=.131).

CONCLUSIONS

It has been shown that the rates of tumour control in meningiomas are not related to Simpson grades. In falx/parasagittal and skull base meningiomas, more aggressive attempts of tumour resection must be balanced against the risks of damaging critical neurovascular structures. In convexity meningiomas, a Simpson's grade I resection should be attempted first.

Phenotypic profile of expanded NK cells in chronic lymphoproliferative disorders: a surrogate marker for NK-cell clonality

Currently, the lack of a universal and specific marker of clonality hampers the diagnosis and classification of chronic expansions of natural killer (NK) cells. Here we investigated the utility of flow cytometric detection of aberrant/altered NK-cell phenotypes as a surrogate marker for clonality, in the diagnostic work-up of chronic lymphoproliferative disorders of NK cells (CLPD-NK). For this purpose, a large panel of markers was evaluated by multiparametric flow cytometry on peripheral blood (PB) CD56^low NK cells from 60 patients, including 23 subjects with predefined clonal (n = 9) and polyclonal (n = 14) CD56^low NK-cell expansions, and 37 with CLPD-NK of undetermined clonality; also, PB samples from 10 healthy adults were included. Clonality was established using the human androgen receptor (HUMARA) assay. Clonal NK cells were found to show decreased expression of CD7, CD11b and CD38, and higher CD2, CD94 and HLADR levels vs. normal NK cells, together with a restricted repertoire of expression of the CD158a, CD158b and CD161 killer-associated receptors. In turn, NK cells from both clonal and polyclonal CLPD-NK showed similar/overlapping phenotypic profiles, except for high and more homogeneous expression of CD94 and HLADR, which was restricted to clonal CLPD-NK. We conclude that the CD94^hi/HLADR⁺ phenotypic profile proved to be a useful surrogate marker for NK-cell clonality.

Tumor infiltrating immune cells in gliomas and meningiomas

Tumor-infiltrating immune cells are part of a complex microenvironment that promotes and/or regulates tumor development and growth. Depending on the type of cells and their functional interactions, immune cells may play a key role in suppressing the tumor or in providing support for tumor growth, with relevant effects on patient behavior. In recent years, important advances have been achieved in the characterization of immune cell infiltrates in central nervous system (CNS) tumors, but their role in tumorigenesis and patient behavior still remain poorly understood. Overall, these studies have shown significant but variable levels of infiltration of CNS tumors by macrophage/microglial cells (TAM) and to a less extent also lymphocytes (particularly T-cells and NK cells, and less frequently also B-cells). Of note, TAM infiltrate gliomas at moderate numbers where they frequently show an immune suppressive phenotype and functional behavior; in contrast, infiltration by TAM may be very pronounced in meningiomas, particularly in cases that carry isolated monosomy 22, where the immune infiltrates also contain greater numbers of cytotoxic T and NK-cells associated with an enhanced anti-tumoral immune response. In line with this, the presence of regulatory T cells, is usually limited to a small fraction of all meningiomas, while frequently found in gliomas. Despite these differences between gliomas and meningiomas, both tumors show heterogeneous levels of infiltration by immune cells with variable functionality. In this review we summarize current knowledge about tumor-infiltrating immune cells in the two most common types of CNS tumors-gliomas and meningiomas-, as well as the role that such immune cells may play in the tumor microenvironment in controlling and/or promoting tumor development, growth and control.

Detailed characterization of alterations of chromosomes 7, 9, and 10 in glioblastomas as assessed by single-nucleotide polymorphism arrays

Glioblastomas are cytogenetically heterogeneous tumors that frequently display alterations of chromosomes 7, 9p, and 10q. We used high-density (500K) single-nucleotide polymorphism arrays to investigate genome-wide copy number alterations and loss of heterozygosity in 35 primary glioblastomas. We focused on the identification and detailed characterization of alterations involving the most frequently altered chromosomes (chromosomes 7, 9, and 10), the identification of distinct prognostic subgroups of glioblastomas based on the cytogenetic patterns of alteration for these chromosomes, and validation of their prognostic impact in a larger series of tumors from public databases. Gains of chromosome 7 (97%), with or without epidermal growth factor receptor (EGFR) amplification, and losses of chromosomes 9p (83%) and 10 (91%) were the most frequent alterations. Such alterations defined five different cytogenetic groups with a significant effect on patient survival; notably, EGFR amplification (29%) was associated with a better survival among older patients, as confirmed by multivariate analysis of a larger series of glioblastomas from the literature. In addition, our results provide further evidence about the relevance of other genes (eg, EGFR, CDKN2A/B, MTAP) in the pathogenesis of glioblastomas. Altogether, our results confirm the cytogenetic heterogeneity of glioblastomas and suggest that their stratification based on combined assessment of cytogenetic alterations involving chromosomes 7, 9, and 10 may contribute to the prognostic evaluation of glioblastomas.

Positive response to imatinib mesylate therapy for childhood chronic myeloid leukemia

Chronic myeloid leukemia (CML) is rare in the pediatric population, accounting for 2-3% of childhood leukemia cases, with an annual incidence of one case per million children. The low toxicity profile of imatinib mesylate has led to its approval as a front-line therapy in children for whom interferon treatment has failed or who have relapsed after allogeneic transplantation. We describe the positive responses of 2 children (case 1 - from a 7-year-old male since May 2005; case 2 - from a 5-year-old female since June 2006) with Philadelphia-positive chromosome CML treated with imatinib (300 mg/day, orally) for up to 28 months, as evaluated by morphological, cytogenetic, and molecular approaches. Our patients are alive, are in the chronic phase, and are in continuous morphological complete remission.

Patient gender is associated with distinct patterns of chromosomal abnormalities and sex chromosome linked gene-expression profiles in meningiomas

The female predominance of meningiomas has been established, but how this is affected by hormones is still under discussion. We analyzed the characteristics of meningiomas from male (n = 53) and female (n = 111) patients by interphase fluorescence in situ hybridization (iFISH). In addition, in a subgroup of 45 (12 male and 33 female) patients, tumors were hybridized with the Affymetrix U133A chip. We show a higher frequency of larger tumors (p = .01) and intracranial meningiomas (p = .04) together with a higher relapse rate (p = .03) in male than in female patients. Male patients had a higher percentage of del(1p36) (p < .001), while loss of an X chromosome was restricted to tumors from female patients (p = .008). In turn, iFISH studies showed a higher frequency of chromosome losses, other than monosomy 22 alone, in meningiomas from male patients (p = .002), while female patients displayed a higher frequency of chromosome gains (p = .04) or monosomy 22 alone (p = .03) in the ancestral tumor clone. Interestingly, individual chromosomal abnormalities had a distinct impact on the recurrence-free survival rate of male versus female patients. In turn, gene expression showed that eight genes (RPS4Y1, DDX3Y, JARID1D, DDX3X, EIF1AY, XIST, USP9Y, and CYorf15B) had significantly different expression patterns (R(2) > 0.80; p < .05) in tumors from male and female patients. In summary, we show the existence of different patterns of chromosome abnormalities and gene-expression profiles associated with patient gender, which could help to explain the slightly different clinical behavior of these two patient groups.

Early recurrences in histologically benign/grade I meningiomas are associated with large tumors and coexistence of monosomy 14 and del(1p36) in the ancestral tumor cell clone

Tumor recurrence is the major clinical complication in meningiomas, and its prediction in histologically benign/grade I tumors remains a challenge. In this study, we analyzed the prognostic value of specific chromosomal abnormalities and the genetic heterogeneity of the tumor, together with other clinicobiological disease features, for predicting early relapses in histologically benign/grade I meningiomas. A total of 149 consecutive histologically benign/grade I meningiomas in patients who underwent complete tumor resection were prospectively analyzed. Using interphase fluorescence in situ hybridization, we studied the prognostic impact of the abnormalities detected for 11 different chromosomes, together with other relevant clinicobiological and histopathological characteristics of the disease, on recurrence-free survival (RFS) at 2.5, 5, and 10 years. From the prognostic point of view, losses of chromosomes 9, 10, 14, and 18 and del(1p36) were associated with a shorter RFS at 2.5, 5, and 10 years. Similarly, histologically benign/grade I meningiomas showing coexistence of monosomy 14 and del(1p36) in the ancestral tumor cell clone displayed a higher frequency of early relapses. In fact, coexistence of -14 and del(1p36) in the ancestral tumor cell clone, together with tumor size, represented the best combination of independent prognostic factors for the identification of those patients with a high risk of an early relapse. Our results indicate that patients with large histologically benign/grade I meningiomas carrying monosomy 14 and del(1p36) in their ancestral tumor cell clone have a high probability of relapsing early after diagnostic surgery. These findings suggest the need for closer follow-up in this small group of patients.

[Cytogenetic alterations in meningioma tumors and their impact on disease outcome]

In recent years important advances have been achieved in the understanding of the genetic abnormalities present in meningioma tumors and its association with the ontogeny and progression of these tumor. Accordingly, while the presence of monosomy 22/22q-, associated with mutation of the NF2, BAM22, RRP22, GAR22, MN1, SMARCB1, CLH22 and/or LARGE genes, is associated with neoplasic transformation, other alterations such us monosomy 14, del(1p), different chromosomal abnormalities localized at 9p, 10q and 17q and complex karyotypes are frequently related to tumor progression. From the clinical point of view, currently available information about the impact of the different cytogenetic abnormalities on disease behavior and patient outcome is still scanty; nevertheless, the presence of gains of chromosome 22 in the context of a hyperdiploid karyotype, as well as del(1p) and monosomy 14 have been associated with a statistically significantly shorter recurrence-free survival, this later abnormality showing an independent prognostic value.

The cytogenetic relationship between primary and recurrent meningiomas points to the need for new treatment strategies in cases at high risk of relapse

PURPOSE

Recurrence is the major factor influencing the clinical outcome of meningioma patients although the exact relationship between primary and recurrent tumors still needs to be clarified. The aim of the present study is to analyze the cytogenetic relationship between primary and subsequent recurrent meningiomas developed within the same individual.

EXPERIMENTAL DESIGN

Multicolor interphase fluorescence in situ hybridization was done for the identification of numerical abnormalities of 12 chromosomes in single-cell suspensions from 59 tumor samples corresponding to 25 recurrent meningioma patients. In 47 of these tumors, the distribution of different tumor cell clones was also analyzed in paraffin-embedded tissue sections. In parallel, 132 nonrecurrent cases were also studied.

RESULTS

Most recurrent meningiomas showed complex cytogenetic aberrations associated with two or more tumor cell clones in the first tumor analyzed. Interestingly, in most individuals (74%), exactly the same tumor cell clones identified in the initial lesion were also detected in the subsequent recurrent tumor samples. In the recurrent tumor samples of the remaining cases (26%), we observed tumor cell clones related to those detected in the initial lesion but which had acquired one or more additional chromosome aberrations associated with either the emergence of new clones with more complex karyotypes or the disappearance of the most representative clones from the primary lesions. Multivariate analysis of prognostic factors showed that the Maillo et al. prognostic score, based on age of patient, tumor grade, and monosomy 14, together with tumor size was the best combination of independent variables for predicting tumor recurrence at diagnosis.

CONCLUSION

Overall, our results indicate that the development of recurrent meningiomas after complete tumor resection is usually due to regrowth of the primary tumor and rarely to the emergence of an unrelated meningioma, underlining the need for alternative treatment strategies in cases at high risk of relapse, particularly those with a high Maillo et al. prognostic score and larger tumors.

A new automated flow cytometry data analysis approach for the diagnostic screening of neoplastic B-cell disorders in peripheral blood samples with absolute lymphocytosis

Currently, multiparameter flow cytometry immunophenotyping is the selected method for the differential diagnostic screening between reactive lymphocytosis and neoplastic B-cell chronic lymphoproliferative disorders (B-CLPD). Despite this, current multiparameter flow cytometry data analysis approaches still remain subjective due to the need of experienced personnel for both data analysis and interpretation of the results. In this study, we describe and validate a new automated method based on vector quantization algorithms to analyze multiparameter flow cytometry immunophenotyping data in a series of 307 peripheral blood (PB) samples. Our results show that the automated method of analysis proposed compares well with currently used manual approach and significantly improves semiautomated approaches and, that by using it, a highly efficient discrimination with 100% specificity and 100% sensitivity can be made between normal/reactive PB samples and cases with B-CLPD based on the total B-cell number and/or the sIgkappa+/sIglambda+ B-cell ratio. In addition, the method proved to be able to detect the presence of pathologic neoplastic B-cells even when these are present at low frequencies (<5% of all lymphocytes in the sample) and in poor-quality samples enriched in 'noise' events.

Microarray-Based Analysis of Spinal versus Intracranial Meningiomas: Different Clinical, Biological, and Genetic Characteristics Associated with Distinct Patterns of Gene Expression

It has long been recognized that spinal meningiomas show particular clinical and histological features. Here, we compare the clinico-biological characteristics as well as the genetic abnormalities and patterns of gene expression of spinal and intracranial meningiomas. Fourteen spinal and 141 intracranial meningioma patients were analyzed at diagnosis. In all tumors, interphase fluorescence in situ hybridization (iFISH) studies were performed for the detection of quantitative abnormalities for 11 different chromosomes. Additionally, microarray analyses were performed on a subgroup of 18 histologically benign meningiomas (7 spinal and 11 intracranial). Upon comparison with intracranial tumors, spinal meningiomas showed a marked predominance of psammomatous and transitional tumors (p = 0.001), together with a higher proportion of cases displaying a single tumor cell clone by iFISH (p = 0.004). In 86% of the spinal versus 56% of the intracranial tumors (p = 0.01), the ancestral tumor cell clone detected showed either absence of any chromosomal abnormality or monosomy 22/22q- alone. Analysis of gene expression profiles showed differential expression between spinal and intracranial meningiomas for a total of 1555 genes, 35 of which allowed a clear distinction between both tumor types. Most of these 35 genes (n = 30) showed significantly higher expression among spinal tumors and corresponded to genes involved in signal transduction pathways, which did not show a significantly different expression according to tumor histopathology. In summary, we show the occurrence of unique patterns of genetic abnormalities and gene expression profiles in spinal as compared to intracranial meningiomas that provide new insights into the molecular pathways involved in the tumorigenesis and progression of spinal meningiomas, and could help explain their particular clinical and histological features.

Lineage involvement in chronic myeloid leukaemia: comparison between MBCR/ABL+ and mBCR/ABL+ cases

The relationship between different Abelson/breakpoint cluster region (BCR/ABL+) gene rearrangements and the involvement of different haematopoietic cell lineages were investigated in 15 chronic myeloid leukaemia patients. Analysis of purified cell populations confirmed the involvement of the neutrophil (89%), monocytic (89%), eosinophil (88%), erythroid (100%), and CD34(+) cells (100%) in virtually all patients, without differences between minor BCR/ABL+ and major BCR/ABL+ cases; BCR/ABL+ B- and natural killer (NK)-cells were detected in 43% and 31% of cases, respectively, whereas BCR/ABL+ T-cells were rare (7%). All three minor BCR/ABL+ patients showed involvement of both B- and NK-cells, which was infrequent (27%, P = 0.06 and 10%, P = 0.01) among major BCR/ABL+ cases.

Genetic heterogeneity of BCR/ABL+ adult B-cell precursor acute lymphoblastic leukemia: impact on the clinical, biological and immunophenotypical disease characteristics

Philadelphia-positive (Ph(+)) B-cell precursor acute lymphoblastic leukemia (BCP-ALL) is a genetically heterogeneous disease with a very poor prognosis. In this study, we analyzed the frequency of supernumerary Ph, trisomy 8, monosomy 7, and del(9p21) by FISH and its relationship with the characteristics of the disease, in 46 BCR/ABL(+) adult BCP-ALL patients. The frequency of supernumerary Ph, trisomy 8, monosomy 7 and del(9p21) was 30%, 20%, 15%, and 24%, respectively. Although all patients displayed a BII/common phenotype, supernumerary Ph and trisomy 8 were associated with higher expression of CD19 and CD22 and of CD19, CD34, CD45, and HLA-DR, respectively; in turn, cases with monosomy 7 showed lower CD19, CD22, CD34, and cCD79a and del(9p21)(+) blasts were CD13(-) and CD33(-). Overall, similar clinical and hematological features were observed at presentation, independently of the underlying genetic abnormalities. However, relapse-free survival (RFS) was significantly shorter in cases with supernumerary Ph, trisomy 8, and del(9p21), the latter being the most powerful independent prognostic factor for RFS.

Characterization of chromosome 14 abnormalities by interphase in situ hybridization and comparative genomic hybridization in 124 meningiomas: correlation with clinical, histopathologic, and prognostic features

We analyzed quantitative chromosome 14 abnormalities in 124 meningiomas by interphase fluorescence in situ hybridization (iFISH) and confirmed the nature of abnormalities by comparative genomic hybridization (CGH). We correlated the abnormalities with clinical, histopathologic, and prognostic factors. Of 124 cases, 50 (40.3%) showed loss (14.5%) or gain (25.8%) of the 14q32 chromosome region by iFISH. Most corresponded to numeric abnormalities: monosomy (12.9%), trisomy (1.6%), or tetrasomy (24.2%); in only 2 cases (1.6%), chromosome 14 loss did not involve the whole chromosome and was restricted to the 14q31-q32 region (confirmed by CGH). Cases with gain or monosomy corresponded more frequently to histologically malignant tumors (P = .009). Patients with monosomy 14/14q-, but not those with gain, more often were male (P = .04) and had a greater incidence of recurrence (P = .003) and shorter relapse-free survival (P = .03). The 2 patients with loss limited to 14q31-q32 had histologically benign tumors and no relapse after more than 5 years' follow-up. Most meningiomas with chromosome 14 abnormalities have numeric changes, with interstitial deletions of 14q31-q32 present in few cases. Of the abnormalities detected, only monosomy 14 showed an adverse prognostic impact.

Intratumoral patterns of clonal evolution in meningiomas as defined by multicolor interphase fluorescence in situ hybridization (FISH): is there a relationship between histopathologically benign and atypical/anaplastic lesions?

Meningiomas are cytogenetically heterogeneous tumors in which chromosome gains and losses frequently occur. Based on the intertumoral cytogenetic heterogeneity of meningiomas, hypothetical models of clonal evolution have been proposed in these tumors which have never been confirmed at the intratumoral cell level. The aim of this study was to establish the intratumoral patterns of clonal evolution associated with chromosomal instability in individual patients as a way to establish tumor progression pathways in meningiomas and their relationship with tumor histopathology and behavior. A total of 125 meningioma patients were analyzed at diagnosis. In all cases, multicolor interphase fluorescence in situ hybridization (iFISH) studies were performed on fresh tumor samples for the detection of quantitative abnormalities for 11 different chromosomes. In addition, overall tumor cell DNA content was measured in parallel by flow cytometry. iFISH studies were also performed in parallel on tissue sections in a subset of 30 patients. FISH studies showed that 56 (45%) of the 125 cases analyzed had a single tumor cell clone, all these cases corresponding to histologically benign grade I tumors. In the remaining cases (55%) more than one tumor cell clone was identified: two in 45 cases (36%), three in 19 (15%), and four or more clones in five cases (4%). Overall, flow cytometric analysis of cell DNA contents showed the presence of DNA aneuploidy in 44 of these cases (35%), 30% corresponding to DNA hyperdiploid and 5% to hypodiploid cases; from the DNA aneuploid cases, 35 (28%) showed two clones and 9 (7%) had three or more clones. A high degree of correlation (r >/= 0.89; P < 0.001) was found between FISH and flow cytometry as regards the overall quantitative DNA changes detected with both techniques, the former being more sensitive. Among the cases with chromosome abnormalities, the earliest tumor cell clone observed was frequently characterized by the loss of one or more chromosomes (64% of all meningiomas); loss of either a single chromosome 22 or, less frequently, of a sex chromosome (X or Y) and del (1p) was commonly found as the single initial cytogenetic aberration (30%, 5%, and 5% of the cases, respectively). Interestingly, an isolated loss of chromosome 22 was only found as the initial abnormality in one out of 14 atypical/anaplastic meningiomas, while the same cytogenetic pattern was present in the ancestral tumor cell clone of 32% of the benign tumors. Cytogenetic patterns based on chromosome gains were found in the ancestral tumor cell clone in 4% of the patients, 2% corresponding to tetraploid tumors. Overall, cytogenetic evolution of the earliest tumor cell clones was frequently associated with tetraploidization (31%). Our results show that meningiomas are genetically heterogeneous tumors that display different patterns of numerical chromosome changes, with the presence of more than one tumor cell clone detected in almost half of the cases including all atypical/anaplastic cases. Interestingly, the pathways of intratumoral clonal evolution observed in the benign tumors were different from those observed in atypical/anaplastic meningiomas, suggesting that the latter tumors might not always represent a more advanced stage of histologically benign meningiomas.

New classification scheme for the prognostic stratification of meningioma on the basis of chromosome 14 abnormalities, patient age, and tumor histopathology

PURPOSE

Meningiomas are usually considered benign tumors. However, relapses occur in 10% to 20% of all patients, including both histopathologically aggressive and benign tumors. This study explored the value of numerical abnormalities for 10 different chromosomes in meningiomas for predicting relapse-free survival (RFS).

PATIENTS AND METHODS

This study prospectively analyzed the frequency of numerical abnormalities of chromosomes 1, 9, 10, 11, 14, 15, 17, 22, X, and Y in 70 meningioma patients by fluorescence in situ hybridization and their relationship with disease characteristics at diagnosis and patients' outcome.

RESULTS

Results showed the presence of numerical abnormalities for one or more chromosomes in most patients (77%). Chromosome 22 in the whole series and chromosome Y in males were those more frequently altered, followed by chromosomes 1, 14, and X in females. Patients with abnormalities of chromosomes 1, 9, 10, 11, 14, 15, 17, the sex chromosomes, and gains of chromosome 22 were associated with adverse prognostic features, more frequent relapses, and shorter RFS. Multivariate analysis showed that tumor grade together with chromosome 14 status and age were the best combination of independent variables for predicting RFS. According to these variables, all patients with a score of two or more than two adverse prognostic factors had experienced relapse at 5 years, whereas none of those with a score of zero had experienced relapse 10 years after surgery.

CONCLUSION

In addition to age and histologic grade, abnormalities of chromosome 14 contribute to a better prognostic stratification of meningioma patients at diagnosis. Additional prospective studies in larger series of patients, also including larger numbers of patients who experienced relapse, are necessary to confirm the utility of the proposed predictive model.

Patterns of BCR/ABL gene rearrangements by interphase fluorescence in situ hybridization (FISH) in BCR/ABL+ leukemias: incidence and underlying genetic abnormalities

Interphase fluorescence in situ hybridization (iFISH) is increasingly used for the identification of BCR/ABL gene rearrangements in chronic myeloid leukemia (CML) and acute lymphoblastic leukemia (ALL). In the present study, we have explored the incidence of both typical and atypical iFISH patterns of BCR/ABL gene rearrangements in a series of 168 consecutive BCR/ABL+ patients--135 CML, 31 precursor B-ALL and two acute myeloblastic leukemia (AML) cases--and established their underlying genetic alterations through further molecular and chromosome analyses. Two different FISH probes (Vysis Inc., Downers Grove, IL, USA) were used: the LSI BCR/ABL dual color extra signal (ES) and the dual color dual fusion BCR/ABL probe (D-FISH). Our results show that most BCR/ABL+ patients (83%, including 88% of all CML, 61% of ALL and one of two AML) displayed typical iFISH patterns of either Major (M) BCR/ABL (87% of CML, 13% of ALL and one of the two AML) or minor (m) BCR/ABL gene rearrangements (1% of all CML and 48% of ALL cases) with the two probes. Further molecular and cytogenetic studies confirmed the presence of such typical rearrangements in all except one of these ALL cases who had coexistence of an MBCR/ABL and an mBCR/ABL gene rearrangement together with monosomy 9. In the remaining 29 cases (17%), up to five different atypical iFISH patterns were detected with the ES probe. Atypical iFISH patterns were most frequently due to additional numerical changes--most often supernumerary Philadelphia (Ph) chromosome (7%) but also gain or loss of chromosome 9 (1%) or 22 (1%). Deletion of 9q sequences proximal to the breakpoint were also frequently observed with the ES probe (8%). Application of the D-FISH probe showed that in most of these latter cases (5%) deletion of 22q sequences distal to the breakpoint also occurred. The remaining cases with atypical iFISH had cryptic insertion of BCR in 9q34 (1%). Exact interpretation of each iFISH pattern was supported by FISH on metaphases and molecular determination of the BCR breakpoint. In summary, our results indicate that despite the high incidence of typical iFISH patterns of BCR/ABL gene rearrangements, atypical patterns are also found in BCR/ABL+ acute leukemias; the precise definition of the alteration present in individual cases is dependent on metaphase studies and molecular definition of the breakpoint.

Fluorescence in situ hybridization analysis of aneuploidization patterns in monoclonal gammopathy of undetermined significance versus multiple myeloma and plasma cell leukemia

BACKGROUND

Monoclonal gammopathy of undetermined significance (MGUS) is a clonal plasma cell (PC) disorder usually characterized by a benign clinical course. However, in approximately 25% of patients, the disorder has been found to evolve into a multiple myeloma (MM). The mechanism leading to the evolution of MGUS remains unknown. The aim of the current study was, first, to assess by interphase fluorescence in situ hybridization (FISH) the incidence of numerical abnormalities of chromosomes 6, 9, 13, and 17 in MGUS patients and to compare it with that found in MM and PC leukemia (PCL) patients and, second, to explore the potential heterogeneity of the pathologic PC in MGUS as a way to identify unique cytogenetic patterns different from those frequently observed in MM and PCL.

METHODS

Numerical abnormalities of chromosomes 6, 9, 13, and 17 were investigated by dual- and triple-color FISH in bone marrow PC from 208 patients corresponding to MGUS (n = 30), MM (n = 158), and PCL (n = 20) cases. In MGUS and MM patients with < 10% PC, both normal and phenotypically aberrant PC were discriminated by multiparameter flow cytometry, the latter subset being specifically sorted for FISH analysis with a purity of 93% +/- 6%.

RESULTS

Overall, 57% of the MGUS patients displayed abnormalities for at least 1 of the 4 chromosomes analyzed compared with 75% of both MM and PCL cases. The most common single chromosome abnormalities detected in MGUS were gains of chromosomes 9 (23%) and/or 6 (21%) and loss of chromosomes 13 (21%) and/or 17 (17%). Compared with MM patients, MGUS patients were found to have both a lower incidence of gains of chromosome 9 (23% vs. 54%, P = 0.002) and monosomy 13/13q(-) deletions (21% vs. 38%, P = 0.07); with respect to PCL cases, MGUS patients were found to have a lower incidence of monosomy 13/13q(-) deletions (21% vs. 75%, P < 0.001) together with a slightly higher frequency of gains of both chromosomes 6 (21% vs. 0%, P = 0.05) and 9 (23% vs. 7%, P = 0.1). The simultaneous use of two or three different chromosome probes showed that within the purified compartment of phenotypically aberrant PC from most MGUS patients (67%), more than 1 PC clone could be identified. In contrast, the incidence of 2 or more PC clones was much lower in MM (19%, P < 0.001) and PCL (15%, P = 0.003). Interestingly, although some FISH patterns were shared by both groups of diseases (i.e., monosomy 13/13q(-) deletions alone, gains of chromosome 9 alone or together with trisomy 6), others were found almost exclusively in either MGUS (i.e., a clone with monosomy 6 and/or 17 together with nuclei displaying a normal chromosome number) or in MM (i.e., monosomy 13/13q(-) deletions together with gains of chromosome 6 and/or 9).

CONCLUSIONS

In summary, the results of the current study showed that MGUS patients displayed a high incidence of numerical alterations, which are usually associated with the presence of more than one tumor cell clone. It is interesting to note that the cytogenetic patterns observed in the aneuploid PC clones from MGUS patients were frequently different from those observed in both MM and PCL.

Incidence of numerical chromosome aberrations in meningioma tumors as revealed by fluorescence in situ hybridization using 10 chromosome-specific probes

OBJECTIVE

Although information on the cytogenetic characteristics of meningioma tumors has accumulated progressively over the past few decades, information on the genetic heterogeneity of meningiomas is still scanty. The aim of the present study was to analyze by interphase fluorescence in situ hybridization (FISH) the incidence of numerical abnormalities for chromosomes 1, 9, 10, 11, 14, 15, 17, 22, X, and Y in a group of 70 consecutive meningioma tumors. Another goal was to establish the potential associations among the altered chromosomes, as a way to assess both intertumoral and intratumoral heterogeneity.

METHODS

For the purpose of the study, 70 patients diagnosed with meningioma were analyzed. Interphase FISH for the detection of numerical abnormalities for chromosomes 1, 9, 10, 11, 14, 15, 17, 22, X, and Y was applied to fresh tumor samples from each of the patients studied.

RESULTS

The overall incidence of numerical abnormalities was 76%. Chromosome Y in males and chromosome 22 in the whole series were the most common abnormalities (46% and 61%, respectively). Despite the finding that monosomy of chromosome 22/22q(-) deletions are the most frequent individual abnormality (53%), we have observed that chromosome gains are significantly more common than chromosome losses (60% versus 40%). Chromosome gains corresponded to abnormalities of chromosomes 1 (27%), 9 (25%), 10 (23%), 11 (22%), 14 (33%), 15 (22%), 17 (23%), and X in females (35%) and males (23%) whereas chromosome losses apart from chromosome 22 frequently involved chromosomes 14 (19%), X in males (23%), and Y in males (32%). Although an association was found among most gained chromosomes on one side and chromosome losses on the other side, different association patterns were observed. Furthermore, in the latter group, monosomy 22/22q(-) was associated with monosomy X in females and monosomy 14/14q(-) was associated with nulisomy Y in males. In addition, chromosome losses usually involved a large proportion of the tumor cells whereas chromosome gains were restricted to small tumor cell clones, including tetraploid cells.

CONCLUSIONS

Our results show that meningiomas are genetically heterogeneous tumors that display different patterns of numerical chromosome changes, as assessed by interphase FISH.

Continuous oral cytarabine ocfosfate with interferon-alpha-2b for patients with newly diagnosed chronic myeloid leukaemia: a pilot study

Recombinant(R) interferon alpha (r-IFN-alpha) has been shown to be an effective drug for chronic myeloid leukaemia (CML). However, higher response rates can be achieved using cytarabine along with r-IFN-alpha. YNK01 is a derivative of cytosine arabinoside for oral administration. So far, the only published experience with continuous YNK01 was in advanced CML (10 cases). We have performed a pilot study to evaluate the efficacy and toxicity of the combined therapy r-IFN-alpha and daily oral YNK01 in patients with newly diagnosed Ph+ CML. Ten previously untreated patients were included in the study. Among those patients evaluable for cytogenetic response, 87% (seven out of eight) reached a major cytogenetic response with four reaching complete cytogenetic response (50%). The most significant side-effects were gastrointestinal. Macrocytic anaemia was observed in three patients. In conclusion, continuous oral administration of YNK01 in combination with IFN-alpha is safe and can result in high-cytogenetic response rates.

Evaluation of a CD61 MoAb method for enumeration of platelets in thrombocytopenic patients and its impact on the transfusion decision-making process

BACKGROUND

Almost all automated hematology cell analyzers use methods based on either the impedance (PLTi) or the optical (PLTo) properties of the cells for performing platelet counts. To improve the accuracy of platelet counts in peripheral blood (PB), the use of CD61 (GPIIIa) MoAbs (ImmunoPLT method) has recently been introduced in an automated hematology blood-analyzer system (Cell-Dyn 4000, Abbott Diagnostics).

STUDY DESIGN AND METHODS

A comparative evaluation was made of the accuracy and precision of the three methods currently available in the Cell-Dyn 4000 automated hematology cell analyzer for counting the number of platelets per microliter of PB in a total of 47 patients with chemotherapy-induced thrombocytopenia. A flow cytometric PB platelet count was also performed in parallel and used as an external reference.

RESULTS

PB platelet counts showed a good correlation among the PLTo, CD61-ImmunoPLT, and flow cytometric methods. In contrast, the PLTi procedure usually provided an overestimation of the number of platelets per microliter. Although a good correlation was observed between the flow cytometric reference method and both the ImmunoPLT and PLTo methods, the highest degree of agreement was found for the ImmunoPLT techniques (94% vs. 67%). A comparative analysis of the PLTo and CD61-ImmunoPLT methods with regard to their value for predicting platelet transfusion needs on the basis of specific flow cytometric platelet count thresholds showed a good correlation when the cutoff level of 10,000 platelets per microL was used. In contrast, at the threshold of 20,000 platelets per microL, slight differences were observed between the PLTo and CD61-ImmunoPLT procedures for predicting transfusion needs.

CONCLUSION

Such results indicate that, if the CD61-ImmunoPLT method is used in the platelet transfusion decision-making process, unnecessary platelet transfusions could be avoided in up to 17.5 percent of persons with a PLTo count of <20,000 platelets per microL.

Gains of chromosome 22 by fluorescence in situ hybridization in the context of an hyperdiploid karyotype are associated with aggressive clinical features in meningioma patients

BACKGROUND

Meningiomas usually are considered to be benign tumors; however, 10-20% of cases recur. Few disease characteristics have proved to have prognostic impact for predicting disease free survival. The objective of the current study was to explore the prognostic value of numeric abnormalities of chromosome 22 for meningioma patients.

METHODS

In this study, the authors prospectively analyzed the incidence of numeric chromosome abnormalities of chromosome 22 by interphase fluorescence in situ hybridization, using a specific probe for the bcr gene located in chromosome 22q11.2, on a total of 88 consecutive meningioma patients. The authors also analyzed its correlation with both the clinicobiologic characteristics at presentation and the patient's outcome.

RESULTS

The authors' results show that monosomy 22 was present in 49% of the cases and that this numeric chromosomal abnormality is not associated with other prognostic features of the disease. In contrast, gains (trisomy/tetrasomy) of chromosome 22 were detected in 8 (9%) cases who simultaneously showed gains for other chromosomes and represent an adverse prognostic factor regarding disease free survival (P = 0.001); in addition, trisomy/tetrasomy 22 was more frequently related to younger patients (P = 0.001), aggressive histopathologic features (P < 0.000), a greater incidence of DNA aneuploidy (P =0.006), and a higher proportion of S-phase tumor cells (P = 0.02).

CONCLUSIONS

In summary, the authors conclude that loss of a copy of chromosome 22 is a frequent finding in meningioma tumors, but it does not affect the clinical outcome of these patients. In contrast, gains (trisomy/tetrasomy) of chromosome 22, in the context of an hyperdiploid karyotype, although much less frequent, are associated with a more aggressive disease course.

Adult precursor B-ALL with BCR/ABL gene rearrangements displays a unique immunophenotype based on the pattern of CD10, CD34, CD13 and CD38 expresssion

The Philadelphia chromosome (Ph+) reflects a balanced reciprocal translocation between the long arms of chromosomes 9 and 22 [t(9;22)(q34;q11.2] involving the BCR and ABL genes. At present, detection of BCR/ABL gene rearrangements is mandatory in precursor-B-ALL patients at diagnosis for prognostic stratification and treatment decision. In spite of the clinical impact, no screening method, displaying a high sensitive and specificity, is available for the identification of BCR/ABL+ precursor-B-ALL cases. The aim of the present study was to explore the immunophenotypic characteristics of precursor B-ALL cases displaying BCR/ABL gene rearrangements using multiple stainings analyzed by quantitative flow cytometry in order to rapidly (<1 h) identify unique phenotypes associated with this translocation. From the 82 precursor-B-ALL cases included in the study 12 displayed BCR/ABL gene rearragements, all corresponding to adult patients, four of which also displayed DNA aneuploidy. Our results show that BCR/ABL+ precursor B-ALL cases constantly displayed a homogeneous expression of CD10 and CD34 but low and relatively heterogeneous CD38 expression, together with an aberrant reactivity for CD13. In contrast, this unique phenotype was only detected in three out of 70 BCR/ABL cases. Therefore, the combined use of staining patterns for CD34, CD38 and CD13 expression within CD10-positive blast cells is highly suggestive of BCR/ABL gene rearrangements in adults with precursor B-ALL.

Low frequency of the TEL/AML1 fusion gene in acute lymphoblastic leukaemia in Spain

We report on a series of Spanish patients with acute lymphoblastic leukaemia in whom the t(12;21) [TEL/AML1] translocation could not be identified with two sensitive techniques: reverse transcript-polymerase chain reaction (RT-PCR) and fluorescence in-situ hybridization (FISH). 101 cases were analysed: 38 children (29 B-cell precursor; nine T-cell precursor) and 63 adults (48 B-cell precursor; 15 T-cell precursor). Specific RT-PCR to amplify the TEL/AML1 fusion transcript was negative in all 101 cases. Moreover, all 38 paediatric samples were also negative by interphase FISH analysis for the presence of the TEL/AML1 fusion. These results suggest the existence of geographic/race variations in the genotype of acute lymphoblastic leukaemia (ALL).

The recovery of acute pancreatitis depends on the enzyme amount stored in zymogen granules at early stages

Little is known about the changes in pancreatic enzyme storage in acute pancreatitis. We have performed flow cytometric studies of zymogen granules from rats with acute pancreatitis induced by hyperstimulation with caerulein. A comparison was made with rats treated with hydrocortisone (10 mg/kg/day) over 7 days before inducing pancreatitis in order to find out whether the amount of enzymes stored in the pancreas plays a key role in the development of pancreatitis. The potentially therapeutic effect of L-364,718 (0.1 mg/kg/day, for 7 days), a CCK receptor antagonist, was assayed in the rats with caerulein-induced pancreatitis which had previously received the hydrocortisone treatment. A significant increase in the intragranular enzyme content was observed 5 h after hyperstimulation with caerulein. The highest values were reached in the rats previously treated with hydrocortisone. The greatest pancreatic enzyme load was parallel to the highest values in plasma amylase, edema and haematocrit observed. Acute pancreatitis was reversed seven days later. At this stage smaller granules appeared in the pancreas whose enzyme content was similar to that of controls when no treatment was applied after pancreatitis. In contrast, L-364,718 administration prevented the favourable evolution of pancreatitis since the antagonism exerted on CCK receptors induced a blockade of secretion of the large amounts of enzymes stored in the pancreas. Moreover, the enzyme content in zymogen granules was below normal values since the stimulatory CCK action on enzyme synthesis can be inhibited by L-364,718. Our results suggest that the efficiency of CCK antagonists, as potential therapy, would also depend on the load of enzymes in the pancreas when acute pancreatitis is produced.

The flow cytometric pattern of CD34, CD15 and CD13 expression in acute myeloblastic leukemia is highly characteristic of the presence of PML-RARalpha gene rearrangements

BACKGROUND AND OBJECTIVE

Rapid identification of AML patients carrying the t(15;17) translocation for treatment decision-making is currently made on the basis of morphologic screening. However, the existence of both false positives and negatives highlights the need for more objective methods of screening AML cases and further molecular confirmation of the t(15;17) translocation.

DESIGN AND METHODS

In the present study we analyzed a total of 111 AML cases in order to investigate whether immunophenotyping based on the assessment of multiple-stainings analyzed at flow cytometry could improve the sensitivity and specificity of morphologic identification of acute promyelocytic leukemia (APL) carrying the t(15;17) translocation. FISH analysis was used as a complementary technique for cases in which morphology and molecular biology yielded discrepant results.

RESULTS

Concordant results between morphology and RT-PCR were found in 102/111 (91.8%) cases: 34 patients had M3/PML-RARalpha+ and 68 non-M3/PML-RARalpha- disease. Nine cases showed discrepants results. Multivariate analysis showed that the best combination of immunologic markers for discriminating between M3/PML-RARalpha+ and non-M3/PML-RARalpha- cases was that of the presence of heterogeneous expression of CD13, the existence of a single major blast cell population, and a characteristic CD34/CD15 phenotypic pattern (p<0.02). A score system based on these parameters was designed, and the 34 M3/PML-RARalpha+ cases showed a score of 3 (presence of the 3 phenotypic characteristics). In contrast, only 1 out of the 68 (1.3%) non-M3/PML-RARalpha- cases had this score, most o these latter cases (53/68, 78%) scoring either 0 or 1. Therefore, among these cases, immunophenotyping showed a sensitivity of 100% and a specificity of 99% for predicting PML/RARalpha gene rearrangements. Of the 9 cases in which morphology and molecular biology results were discrepant, four cases displayed M3 morphology without PML/RARalpha rearrangements by RT-PCR. In only one of these 4 cases did the immunophenotype score 3, this being the only FISH positive case. From the remaining five discrepant cases (non-M3 morphology while positive for PML/RARalpha) two cases had a phenotypic score of 3 and were FISH positive while the other three were negative by FISH. Upon repeating RT-PCR studies, two of these latter three cases became negative.

INTERPRETATION AND CONCLUSIONS

Our results show that immunophenotyping may be of great value for quick screening of APL with PML/RARalpha rearrangements.

Primary plasma cell leukemia: clinical, immunophenotypic, DNA ploidy, and cytogenetic characteristics

We report on a series of 26 patients diagnosed with primary (de novo) plasma cell (PC) leukemia (PCL) in whom we analyzed the clinicobiologic characteristics of the disease together with the immunophenotype, DNA cell content, proliferative index, and numeric chromosomal aberrations of the neoplastic PC, and compared them with 664 multiple myeloma (MM) patients at diagnosis. The median age, sex ratio, and bone lesion extension were similar, but PCL cases displayed a higher prevalence of clinical stage III, extramedullary involvement, and Bence Jones cases, with fewer IgA cases than for MM patients. In addition, according to several prognostic indicators (beta2-microglobulin serum level, proportion of S-phase PCs, proteinuria, calcium serum level, lactate dehydrogenase [LDH] and renal function), the incidence of adverse prognostic factors was significantly higher in PCL versus MM. Immunophenotypic expression was similar for CD38, CD138, CD2, CD3, CD16, CD10, CD13, and CD15, but PCL differed from MM in the expression of CD56, CD9 HLA-DR, CD117, and CD20 antigens. Twenty-two PCL cases were diploid and one was hypodiploid, while most MM cases (57%) showed DNA hyperdiploidy. With the fluorescent in situ hydridization (FISH) technique, 12 of 13 PCL cases displayed the numeric aberrations, -13 (86%), +/-1 (57%), +18 (43%), and -X in women (25%), but they lacked several numeric aberrations usually found in MM such as +3, +6, +9, +11, and +15. PCL cases had a lower overall response to therapy than MM cases (38% v 63%, P =.01332). Among PCL patients, a trend for a worse response was observed in cases treated with melphalan and prednisone (MP) versus polychemotherapy. Overall survival was significantly worse in PCL versus MM patients (8 v 36 months, P <.0001), but it was significantly better in PCL patients treated with polychemotherapy versus MP (18 v 3 months, P =.0137). By contrast, MM patients did not show significant differences in overall survival according to the treatment used, MP or polychemotherapy. Ten variables seemed to predict survival in PCL patients, but only the beta2-microglobulin level and S-phase PCs retained an independent value in multivariate analysis. In summary, our study illustrates that PCs from PCL display singular phenotypic, DNA cell content, and cytogenetic characteristics that lead to a different disease evolution versus MM.

Prognostic value of numerical chromosome aberrations in multiple myeloma: A FISH analysis of 15 different chromosomes

Recent observations indicate that chromosome aberrations are important prognostic factors in patients with multiple myeloma (MM) treated with high-dose chemotherapy. Nevertheless, the inherent problems of conventional cytogenetics have hampered the systematic evaluation of this parameter in series of patients treated with conventional chemotherapy. Fluorescence in situ hybridization (FISH) analysis is an attractive alternative for evaluation of numerical chromosomal changes. In the present study, we analyze the relationship between aneuploidies of 15 different chromosomes assessed by FISH and prognosis in a series of 63 patients with MM treated with conventional chemotherapy. After a median follow-up of 61 months (range, 6 to 109), 49% of patients are still alive with a median survival of 33 months. The overall incidence of numerical chromosome abnormalities was 70%. This incidence significantly increased when seven or more chromosomes were analyzed (53 patients), reaching 81%. Trisomies of chromosomes 6, 9, and 17 were associated with prolonged survival (P = .033, P = .035, and P = .026, respectively); by contrast, overall survival (OS) was lower in cases with monosomy 13 (as assessed by deletion of Rb gene, P = .0012). From the clinical point of view, loss of Rb gene was associated with a poor performance status; low hemoglobin levels; high creatinine, C-reactive protein, and lactic dehydrogenase serum levels; high percentage of bone marrow plasma cells (BMPC); extensive bone lytic lesions; and advanced clinical stage. Other chromosome abnormalities such as trisomy of chromosome 9 and 17 were associated with good prognostic features including high hemoglobin levels, early clinical stage, beta2microglobulin less than 6 micro/mL, and low percentage of BMPC. A multivariate analysis for OS showed that S-phase PC greater than 3% (P = .010) and beta2microglobulin serum levels greater than 6 micro/mL (P = .024), together with monosomy of chromosome 13 (P = .031) and nontrisomy of chromosome 6 (P = .048) was the best combination of independent parameters for predicting survival in patients with MM. According to these results, chromosomal analysis is of great use in patients with MM at diagnosis to have a correct prognostic evaluation for clinical decision making.

Changes in both the membrane and the enzyme content of individual zymogen granules are associated with sodium taurocholate-induced pancreatitis in rats

1. After monitoring the changes associated with necrotizing acute pancreatitis in rats from early stages to 24 h after infusion of 5% sodium taurocholate in the choledocus, we characterized by flow cytometry the zymogen granules that still remained in the pancreas 18 h after sodium taurocholate infusion in order to explore whether alterations in the enzyme content and/or in the composition of the granule membrane could be related to the intracellular mechanisms involved in the development of necrotizing acute pancreatitis. 2. Significant increases in the haematocrit, plasma and peritoneal exudate amylase levels and oedema were observed from the third hour after 5% sodium taurocholate infusion onwards. Additionally, cell alterations such as hypergranulation, dilatation of the endoplasmic reticulum and autophagic vacuoles were found 3 and 6 h after infusion. DNA decrease, degranulation and necrosis were observed from 12 h after sodium taurocholate infusion onwards. 3. Flow cytometric measurements of zymogen granules isolated from rat pancreas 18 h after 5% sodium taurocholate infusion revealed a significant decrease in their internal complexity without major changes in their size. Double staining of granules with Tetragonolobus purpureus lectin, which specifically binds L-fucose and specific anti-trypsinogen or anti-amylase antisera, showed that rats with induced pancreatitis have decreased amounts of L-fucose in the membrane glycoconjugates and lower enzyme content (70% and 30% less for trypsinogen and amylase respectively). 4. A decrease in L-fucose in the membrane together with membrane abnormalities observed by electron microscopy in zymogen granules isolated 18 h after sodium taurocholate infusion indicate an altered synthesis of new granules or lysis of preformed zymogen granules which would favour differential loss of granular enzymes, mainly trypsinogen, which in turn could increase the severity of disease.

Natural anticoagulant proteins and antiphospholipid antibodies in systemic lupus erythematosus

OBJECTIVE

Thrombosis is a relatively common complication in patients with systemic lupus erythematosus (SLE) and is strongly associated with the presence of antiphospholipid antibodies (aPL). The mechanism involved in the pathogenesis of this prothrombotic state remains obscure. We studied 4 natural anticoagulant proteins: protein C, protein S, antithrombin III, and plasminogen in 50 patients diagnosed with SLE.

METHODS

Protein C, antithrombin III, and plasminogen were measured by chromogenic substrates and total and free protein S by electrophoresis. We also determined the prevalence of different aPL (lupus anticoagulant and antibodies against cardiolipin, phosphatidylserine, and phosphatidylinositol).

RESULTS

Ten patients (20%) had a history of thrombosis. Some type of aPL was present in 26 patients (52%). Nine of the 10 patients with history of thrombosis had aPL (p = 0.007). Functional assays for protein C, antithrombin III, and plasminogen were in the normal range in all patients. Low free protein S levels were documented in 19 patients and were associated with the presence of aPL (13/19 were aPL positive) (p < 0.05). Only 4 patients with acquired free protein S deficiency had a history of thrombosis.

CONCLUSION

This study shows an association between aPL and reduced free protein S levels in patients with SLE. Further studies are needed to determine the mechanism and role of this acquired deficiency in the pathogenesis of thrombotic episodes in patients with SLE.

Clinical and biological characteristics of myelodysplastic syndromes with nulisomy Y by fish

BACKGROUND AND OBJECTIVE

In the present study we analyzed the incidence of nulisomy Y by fluorescence in situ hybridization in a group of 24 males diagnosed with myelodysplastic syndromes (MDS). We explored the relationship between this chromosome abnormality and other clinical and biological disease characteristics.

METHODS

Loss of chromosome Y was present in 7 out of the 24 males analyzed (29%); the number of cells carrying this chromosome aberration ranged between 19% and 90%. From the clinicobiological point of view, the group of patients with nulisomy Y showed a higher incidence of RA and RAS FAB subtypes (p = 0.04), a lower WBC count (p = 0.04), a lower proportion of blast cells both in PB (p = 0.009) and BM (p = 0.06) associated with a decreased myeloid/erythroid ratio (p = 0.01).

RESULTS

No clear association was detected between loss of chromosome Y and other numerical chromosome abnormalities involving chromosomes 7 and 8. In contrast, 2 out of the 7 cases with loss of chromosome Y also displayed monosomy 1 by FISH. However, the use of appropriate dual stainings showed that these two abnormalities were present in different cell populations (that is, they never coexisted in the same cell population), which supports the notion of the existence of clonal heterogeneity in MDS patients.

INTERPRETATION AND CONCLUSIONS

From the prognostic point of view, MDS patients with loss of chromosome Y displayed a higher survival rate, although these differences did not reach statistical significance.

Association between trisomy 8 and the immunophenotype of blast cells from acute leukemias secondary to a myelodysplastic syndrome or chronic myeloproliferative disorders

In the present study we have used FISH to analyze the incidence of trisomy 8 in acute leukemias following either a primary myeloproliferative disorder (MPD) or a myelodysplastic syndrome (MDS) and correlated it with both the immunophenotype and the cell-cycle distribution of the leukemic blast cells. Six of the 21 (28%) acute leukemias studied displayed trisomy 8 by FISH. The number of trisomic cells in these cases ranged from 20 to 84%, with a mean of 46 +/- 24%. Trisomy 8 was associated with a homogeneous population of leukemic cells, phenotypically characterized by CD34+/HLADR+/CD13+/CD33+/CD11b-/ CD15-/CD14-. No significant differences were observed on the proliferative rate of cases with trisomy 8, as compared with blast cells from the remaining patients. Overall, our findings suggest that in acute leukemias secondary to MPD or MDS, trisomy 8 is associated with a blockade of myeloid maturation at an early step of the differentiation process.

Detection of the Mbcr/abl translocation in chronic myeloid leukemia by fluorescence in situ hybridization: comparison with conventional cytogenetics and implications for minimal residual disease detection

The correlation between the detection of the Philadelphia chromosome by conventional cytogenetics and the identification of Mbcr/abl translocation by fluorescence in situ hybridization (FISH) in both metaphase and interphase cells is prospectively analyzed in a group of 21 chronic myeloid leukemia (CML) patients. To gain insight into the sensitivity and specificity of the detection of the bcr/abl translocation by FISH, a group of 10 healthy volunteers was also studied. Our results show that for the detection of bcr/abl translocation in CML patients, FISH is more sensitive than conventional cytogenetics because it detects significantly higher proportions of cells carrying the translocation both in metaphase (P < .0002) and interphase nuclei (P < .003). Moreover, in the metaphases of the controls analyzed, no bcr/abl+ chromosome was detected that makes the colocalization of bcr and abl signals in the CML patients highly specific. Conversely, in control interphase nuclei, a small proportion of cells (ranging between 0% and 3%, mean value of 1.7% +/- 0.9%) displaying colocalization of both signals is usually detected. This limits, at least for the moment, the routine use of FISH for the detection of minimal residual disease in CML patients at levels lower than 10(-1).

[Long-term culture: evidence of the capacity of stroma to sustain hematopoiesis of a second inoculum]

PURPOSE

To analyze, in two-stages long term bone marrow cultures (LTBMC), the efficiency of the method used for irradiation of the stroma and to check if after that, it's capable to support the hematopoiesis.

MATERIAL AND METHODS

We have used for the first inoculum, bone marrow cells from eight controls. They were cultured at 2 x 10(6) cells/ml concentration until obtaining a fully confluent stroma which was irradiated with 15 Gy. After that, over this layer, we put a second inoculum with bone marrow cells in four cases, and with peripheral blood cells in four others, at a concentration of 1 x 10(5) cells/mL. In four cases the first inoculum was from a man and the second from a woman. The culture's haematopoietic activity was determined by the number of CFU-GM, total cell counts and the differential counts during four weeks. At the end of the study we recovered the cells from the supernatant of the culture and they were analyzed by in situ hybridization with an alpha centromeric probe specific to the X chromosome.

RESULTS

In all cases we obtained a confluent stroma with production of haematopoiesis (cobblestone areas). The cells recovered at the end of the culture were, in all cases, from the second inoculum because they had a double signal with the X probe. The number of CFU-GM obtained was higher in bone marrow than in peripheral blood (34.5 and 9.2 respectively) however, the total cells were similar in both cases (2.3 x 10(5) and 2.9 x 10(5)) although the cellular subtypes varied depending on the second inoculum (B.M. or P.B.).

CONCLUSION

Our data confirm that the dose of 15 Gy eradicate the haemopoiesis of first inoculum, which allowed to analyze stroma and progenitor cells, separately. In addition, the stroma is capable to support the hematopoiesis generated by progenitor cells from peripheral and bone marrow.

Clinical, biological, and immunophenotypical characteristics of B-cell chronic lymphocytic leukemia with trisomy 12 by fluorescence in situ hybridization

The clinical, biological, and immunophenotypical characteristics of B-cell chronic lymphocytic leukemia (B-CLL) patients with trisomy 12 detected by fluorescence in situ hybridization (FISH) using a chromosome 12 alpha-centromeric probe (D12Z3) were analyzed in the present study. From a total of 104 consecutive B-CLL patients, 21 (20%) displayed trisomy 12, the percentage of trisomic cells ranging from 13% to 76%. From the clinico-biological point of view, patients with trisomy 12 were associated with atypical CLL morphology (43% vs 10%, P = 0.04) and BM diffuse pattern (75% vs. 25%, P = 0.02) together with increased WBC counts (141 +/- 220 vs. 58 +/- 67 x 10(9)/L, P = 0.04). In contrast, no association was detected between the presence of trisomy 12 and other disease characteristics such as age, sex, clinical stage, hepatomegaly, lymphadenopathies, haemoglobin levels and platelet counts, and the cell cycle distribution of PB leukocytes in both groups of patients. Trisomy 12 patients had a significantly higher expression of the FMC7 antigen both in percentage (34 +/- 34% vs. 13 +/- 20%, P = 0.02) and absolute numbers (29 +/- 62 vs. 7 +/- 17 x 10(9)/L, P = 0.007). No major differences were found regarding the expression of mouse rosettes, CD19+, and CD19+/CD5+ lymphocytes. Upon analyzing the correlations between the disease characteristics of trisomy 12 cases, significant associations were found between the percentage of trisomic cells and both the WBC count (r = 0.52, P = 0.02) and the PB lymphocyte count (r = 0.60, P = 0.007).(ABSTRACT TRUNCATED AT 250 WORDS)

Incidence and clinical characteristics of hereditary disorders associated with venous thrombosis

At present, different congenital defects in several proteins--antithrombin III (AT III), protein C (PC), protein S (PS), and plasminogen (PLG)--are known to be causes of hereditary predisposition to thrombosis (thrombophilia). The incidence of these hereditary disorders in our 204 patients (106 males and 98 females) with venous thromboembolism were 4% (three cases deficient in PC, three in PS, two in PLG, and one patient in AT III). Their families were studied. In all cases the disorders were inherited as an autosomal dominant trait. The first thrombotic episodes occurred at a age of below 40 years. There was no relationship between protein levels and the occurrence of thrombosis, although a significant relationship was observed between a positive history of thromboembolic disease and a diagnosis of protein deficiencies. We evaluated the differences between primary thrombosis and secondary thrombosis. The most common thrombotic sites were the deep veins. There were no differences between males and females. Evaluation of PC, PS, AT III, and PLG in patients with thromboembolic disease should be considered.

[Plasminogen deficiencies in 2 Spanish families. Response to the administration of DDAVP]

We describe two families with heterozygous plasminogen deficiency. In the first the patient was a 27 year-old female who suffered an acute episode of ischemic cerebrovascular disease affecting the left temporal lobe documented by arteriographic, gammagraphic and CAT studies. She had no family history of thrombotic conditions. In the other family the propositus was a 31 year-old man with spontaneous deep venous thrombosis in the left leg. His father was also symptomatic, with a history of recurrent thrombotic complications after predisposing factors, that included multiple venous thrombosis and a pulmonary embolism. Laboratory data showed normal hemostasis test results. Antigenic and functional levels of protein C, protein S and antithrombin III were within normal limits. The only abnormality found was decreased plasminogen activity in plasma; antigenic and functional levels were reduced to about half-normal levels. In both cases crossed immunoelectrophoresis revealed a normal migration pattern of plasminogen. Thus, we conclude that our patients were carriers of congenital hypoplasminogenemia or familial type I plasminogen deficiency, due to decreased synthesis. We also reported on fibrinolytic response to infusion of DDAVP, a synthetic analogue of the antidiuretic hormone. Fibrinolytic activity was normal in basal conditions as well as in response to DDAVP infusion.