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Resting heart rate is associated with cardiovascular diseases and mortality in observational and Mendelian randomization studies. The aims of this study are to extend the number of resting heart rate associated genetic variants and to obtain further insights in resting heart rate biology and its clinical consequences. A genome-wide meta-analysis of 100 studies in up to 835,465 individuals reveals 493 independent genetic variants in 352 loci, including 68 genetic variants outside previously identified resting heart rate associated loci. We prioritize 670 genes and in silico annotations point to their enrichment in cardiomyocytes and provide insights in their ECG signature. Two-sample Mendelian randomization analyses indicate that higher genetically predicted resting heart rate increases risk of dilated cardiomyopathy, but decreases risk of developing atrial fibrillation, ischemic stroke, and cardio-embolic stroke. We do not find evidence for a linear or non-linear genetic association between resting heart rate and all-cause mortality in contrast to our previous Mendelian randomization study. Systematic alteration of key differences between the current and previous Mendelian randomization study indicates that the most likely cause of the discrepancy between these studies arises from false positive findings in previous one-sample MR analyses caused by weak-instrument bias at lower P-value thresholds. The results extend our understanding of resting heart rate biology and give additional insights in its role in cardiovascular disease development. The genetics and clinical consequences of resting heart rate (RHR) remain incompletely understood. Here, the authors discover new genetic variants associated with RHR and find that higher genetically predicted RHR decreases risk of atrial fibrillation and ischemic stroke. [ABSTRACT FROM AUTHOR]

Purpose: Portable ultrasonography (P-US) is increasingly used to diagnose syndesmotic instability. The aim of this study was to evaluate syndesmotic instability by measuring the distal tibiofibular clear space (TFCS) in a cadaveric model using P-US with progressive stages of syndesmotic ligamentous transection under external rotation stress. Methods: Ten fresh lower leg cadaveric specimens amputated above the proximal tibiofibular joint were used. Using P-US, the TFCS was evaluated in the intact stage and after progressive sectioning of the (1) anterior–inferior tibiofibular ligament (AITFL), (2) interosseous ligament (IOL), and (3) posterior–inferior tibiofibular ligament (PITFL). The TFCS was measured in both the unstressed (0 Nm) state and with 4.5, 6.0, 7.5, and 9.0 Nm of external rotation stress using a bone hook placed on the first metatarsal bone at each stage of ligamentous transection stage using both P-US and fluoroscopy. Results: When assessed with P-US, partial syndesmotic injury encompassing the AITFL and IOL resulted in significant TFCS widening at 4.5 Nm of external rotation torque when compared to intact state with a TFCS-opening of 2.6 ± 2 mm, p = 0.01. In contrast, no significant differences in TFCS were detected using fluoroscopy. Only a moderate correlation was found between P-US and fluoroscopy. Conclusion: P-US is a useful tool in diagnosing syndesmotic instability during external rotation stress examination. TFCS-opening increased as additional ligaments of the syndesmosis were transected, and application of 4.5 Nm torque was sufficient to detect a difference of 2.6 mm after the IOL cut. [ABSTRACT FROM AUTHOR]

Purpose: This study aim was to detect the impact of lateral ankle ligaments injury on syndesmotic laxity when evaluated arthroscopically in a cadaveric model. The null hypothesis was that lateral ankle ligament injury does not affect the stability of syndesmosis. Methods: Sixteen fresh-frozen above-knee amputated cadaveric specimens were divided into two groups of eight specimens that underwent arthroscopic evaluation of the distal tibiofibular joint. In both the groups, the assessment was first done with all syndesmotic and ankle ligaments intact. Thereafter, Group 1 underwent sequential transection of the three lateral ankle ligaments first to identify the effects of lateral ligament injury: (1) anterior talofibular ligament (ATFL), (2) calcaneofibular ligament (CFL), (3) posterior talofibular ligament (PTFL), then followed by the syndesmotic ligaments, (4) AITFL, (5) Interosseous ligament (IOL), and (6) PITFL. Group 2 underwent sequential transection of the (1) AITFL, (2) ATFL, (3) CFL, (4) IOL, (5) PTFL, and (6) PITFL, which represent the most commonly injured pattern in ankle sprain. In all scenarios, four loading conditions were considered under 100 N of direct force: (1) unstressed, (2) a lateral fibular hook test, (3) anterior to posterior (AP) fibular translation test, and (4) posterior to anterior (PA) fibular translation test. Distal tibiofibular coronal plane diastasis at the anterior and posterior third of syndesmosis, as well as AP and PA sagittal plane translation, were arthroscopically measured. Results: The distal tibiofibular joint remained stable after transection of all lateral ankle ligaments (ATFL, CFL, and PTFL) as well as the AITFL. However, after additional transection of the IOL, the syndesmosis became unstable in both the coronal and sagittal plane. Syndesmosis laxity in the coronal plane was also observed after transection of the ATFL, CFL, AITFL, and IOL. Subsequent transection of the PITFL precipitated syndesmosis laxity in the sagittal plane, as well. Conclusions: The findings from the present study suggest that lateral ankle ligament injuries itself do not directly affect the stability of syndesmosis. However, if it combines with IOL injuries, even partial injuries cause syndesmotic laxity. As a clinical relevance, accurate diagnosis is the key for surgeons to determine syndesmosis fixation whether there is only AITFL injury or combined IOL injury in concomitant acute syndesmotic and lateral ligament injury. [ABSTRACT FROM AUTHOR]

Purpose: To compare the bone healing, clinical, and return to daily activity outcomes after either surgical or conservative management of acute zone 1, 2, and 3 fifth metatarsal fractures. Methods: A literature search was performed to identify studies published from the earliest record to January 2019 using EMBASE (Ovid), MEDLINE via PubMed, CINAHL, and Web of Science. All articles assessing clinical outcomes of acute proximal fifth metatarsal fractures were included. Bone healing and clinical outcomes were thereafter calculated using a simplified pooling method. Results: Thirty-two articles comprising of a total of 1,239 fractures were included, of which one was a randomized controlled trial, seven were prospective studies, and 24 were retrospective studies. 627 zone 1 fractures demonstrated union rates of 93.2% following conservative treatment and 95.1% following surgical treatment. Conservatively managed zone 1 fractures were displaced 49.5% of the time, compared to a rate of 92.8% for the surgically treated cases. For Jones' (zone 2) fractures, bone healing outcomes of conservative versus surgical treatment showed union rates of 77.4% versus 96.3%, refracture rates of 2.4% versus 2.1%, and mean time to union of 11.0 weeks versus 9.4 weeks, respectively. Only ten proximal diaphyseal (zone 3) fractures were reported, with a mean return to work of 8.2 weeks. Conclusion: Acute zone 1 fractures are preferably treated conservatively as similar union rates were found after both conservative and surgical management. In contradistinction, acute zone 2 fractures demonstrate higher union rates and faster time to union when treated surgically. The outcomes of acute zone 3 fractures are rarely reported in the literature, so treatment recommendations remain unclear. Further research of proximal fifth metatarsal fractures is warranted to provide more definitive conclusions, but current findings can aid surgeons during the shared clinical decision making process. Level of evidence: IV. [ABSTRACT FROM AUTHOR]

Purpose: Ankle arthroscopy is widely used for diagnosis of syndesmotic instability, especially in subtle cases. To date, no published article has systematically reviewed the literature in aggregate to understand which instability values should be used intraoperatively. The primary aim was to systematically review the amount of tibiofibular displacement that correlates with syndesmotic instability after a high ankle sprain. A secondary aim is to assess the quality of such research. Methods: Systematic searches of EMBASE (Ovid) and MEDLINE via PubMed, CINAHL, Web of Science, and Google Scholar were used. Inclusion criteria: studies that arthroscopically evaluated the fibular displacement at various stages of syndesmotic ligament injury. Two reviewers independently extracted data and assessed methodological quality using the Anatomical Quality Assessment (AQUA) Tool and methodological index for non-randomized studies (MINORS). Results: Eight cadaveric studies and three clinical studies were included for review. All studies reported displacement in the coronal plane, four studies reported in the sagittal plane, and one reported findings in the rotational plane. Four cadaveric studies had a similar experimental set up and the weighted mean associated with instability in the coronal plane could be calculated and was 2.9 mm at the anterior portion of the distal tibiofibular joint and 3.4 mm at the posterior portion. Syndesmotic instability in the sagittal plane is less extensively studied, however available data from a cadaveric study suggests thresholds of 2.2 mm of posterior fibular translation when performing an anterior to posterior hook test and 2.6 mm of anterior fibular translation when performing a posterior to anterior hook test. Conclusions: The results have concluded that the commonly used 2.0 mm threshold value of distal tibiofibular diastasis may lead to overtreatment of syndesmotic instability, and that using threshold values of 2.9 mm measured at the anterior portion of the incisura and 3.4 mm at the posterior portion may represent better cut off values. Given the ready availability of 3 mm probes among standard arthroscopic instrumentation, at the very least surgeons should use 3 mm in lieu of 2 mm probes intraoperatively. Level of evidence: IV. [ABSTRACT FROM AUTHOR]

TP53 aberrations reportedly predict favorable responses to decitabine (DAC) in acute myeloid leukemia (AML). We evaluated clinical features and outcomes associated with chromosome 17p loss or TP53 gene mutations in older, unfit DAC-treated AML patients in a phase II trial. Of 178 patients, 25 had loss of 17p in metaphase cytogenetics; 24 of these had a complex (CK+) and 21 a monosomal karyotype (MK+). In analyses in all patients and restricted to CK+ and MK+ patients, 17p loss tended to associate with higher rates of complete remission (CR), partial remission (PR), or antileukemic effect (ALE). Despite favorable response rates, there was no significant OS difference between patients with or without loss of 17p in the entire cohort or in the CK+ and MK+ cohort. TP53 mutations were identified in eight of 45 patients with material available. Five of the eight TP53-mutated patients had 17p loss. TP53-mutated patients had similar rates of CR/PR/ALE but shorter OS than those with TP53 wild type (P = 0.036). Moreover, patients with a subclone based on mutation data had shorter OS than those without (P = 0.05); only one patient with TP53-mutated AML had a subclone. In conclusion, 17p loss conferred a favorable impact on response rates, even among CK+ and MK+ patients that however could not be maintained. The effect of TP53 mutations appeared to be different; however, patient numbers were low. Future research needs to further dissect the impact of the various TP53 aberrations in HMA-based combination therapies. The limited duration of favorable responses to HMA treatment in adverse-risk genetics AML should prompt physicians to advance allografting for eligible patients in a timely fashion. [ABSTRACT FROM AUTHOR]

The presence of cytogenetic clonal heterogeneity has been associated with poor prognosis in patients with acute myeloid leukemia (AML). Here, we reassessed this association. The study cohort consisted of all patients with an abnormal karyotype randomized in the EORTC/GIMEMA AML-10 and AML-12 trials. Abnormal karyotypes were classified as no subclones present (cytogenetic abnormality in a single clone), defined subclones present (presence of one to three subclones), and composite karyotypes (CP) (clonal heterogeneity not allowing enumeration of individual subclones). The main endpoints were overall survival (OS) and disease-free survival (DFS). Among 1291 patients with an abnormal karyotype, 1026 had no subclones, 226 at least 1 subclone, and 39 a CP. Patients with defined subclones had an OS similar to those with no subclones (hazard ratio (HR) 1.05, 95% confidence interval (CI) 0.88-1.26), but CP patients had a shorter OS (HR = 1.58, 95% CI 1.11-2.26). However, in a multivariate Cox model stratified by protocol and adjusted for age, cytogenetic risk group, secondary versus primary AML, and performance status, clonal heterogeneity lost its prognostic importance (HR = 1.10, 95% CI 0.91-1.32 for defined subclones versus no subclones; HR = 0.96, 95% CI 0.67-1.38 for CP versus no subclones). Also, the impact of having a donor on DFS was similar in the three clonal subgroups. In summary, in patients with cytogenetic abnormality, presence of subclones had no impact on OS. The dismal outcome in patients with a CP was explained by the known predictors of poor prognosis.Trial Registration: AML-10: ClinicalTrials.gov identifier: NCT00002549, retrospectively registered July 19, 2004; AML12: ClinicalTrials.gov identifier: NCT00004128, registered January 27, 2003. [ABSTRACT FROM AUTHOR]

Acral myxoinflammatory fibroblastic sarcoma is a rare tumor of the distal extremities. We present the hitherto unreported karyotypic abnormalities of this new entity. The tumor presented as a mass in the dorsum of the foot in a 53-year-old woman and showed the typical virocyte-like and lipoblast-like cells in a myxoid and inflammatory background. Cytogenetic analysis revealed a complex karyotype with a reciprocal translocation t(1;10) (p22;q24) in addition to the loss of chromosomes 3 and 13. Fluorescence in situ hybridization with the 769E11YAC and BAC 31L5 and 2H23 probes showed the breakpoint to be located proximally to BCL10 and distally to GOT1 genes on chromosomes 1p22 and 10q24, respectively. The presence of these clonal chromosomal changes supports the neoplastic nature of acral myxoinflammatory fibroblastic sarcoma and underscores that it represents a separate entity. [ABSTRACT FROM AUTHOR]

Angiomyxolipoma is a rare variant of lipoma, two cases of which have recently been described. We report on the hitherto unreported clonal chromosomal changes of a third case of angiomyxolipoma. The karyotype showed a 46,XX,t(7;13)(p15;q14),t(8;12)(q13;p13)[17]/46,XX[3]. The involvement of 13q14, 12p13, and 8q13 supports a relationship with other types of benign lipomatous and myxoid tumors. [ABSTRACT FROM AUTHOR]

In a study of elderly AML patients treated with the hypomethylating agent decitabine (DAC), we noted a surprisingly favorable outcome in the (usually very unfavorable) subgroup with two or more autosomal monosomies (MK2+) within a complex karyotype (Lübbert et al., Haematologica 97:393-401, 2012). We now analyzed 206 myelodysplastic syndrome (MDS) patients (88 % of 233 patients randomized in the EORTC/GMDSSG phase III trial 06011, 61 of them with RAEBt, i.e. AML by WHO) with cytogenetics informative for MK status.. Endpoints are the following: complete/partial (CR/PR) and overall response rate (ORR) and progression-free (PFS) and overall survival (OS). Cytogenetic subgroups are the following: 63 cytogenetically normal (CN) patients, 143 with cytogenetic abnormalities, 73 of them MK-negative (MK-), and 70 MK-positive (MK+). These MK+ patients could be divided into 17 with a single autosomal monosomy (MK1) and 53 with at least two monosomies (MK2+). ORR with DAC in CN patients: 36.1 %, in MK- patients: 16.7 %, in MK+ patients: 43.6 % (MK1: 44.4 %, MK2+ 43.3 %). PFS was prolonged by DAC compared to best supportive care (BSC) in the CN (hazard ratio (HR) 0.55, 99 % confidence interval (CI), 0.26; 1.15, p = 0.03) and MK2+ (HR 0.50; 99 % CI, 0.23; 1.06, p = 0.016) but not in the MK-, MK+, and MK1 subgroups. OS was not improved by DAC in any subgroup. In conclusion, we demonstrate for the first time in a randomized phase III trial that high-risk MDS patients with complex karyotypes harboring two or more autosomal monosomies attain encouraging responses and have improved PFS with DAC treatment compared to BSC. [ABSTRACT FROM AUTHOR]

In the European Organisation for Research and Treatment of Cancer (EORTC)/GMDSSG phase III trial 06011, we compared decitabine (15 mg/m(2) every 8 h for 3 days) with best supportive care (BSC) in patients ≥60 years with myelodysplastic syndromes (MDS) by French-American-British (FAB) criteria. Here, we reinvestigate trial 06011 for the activity and efficacy specifically in patients with refractory anemia with excess blasts in transformation (RAEBt). Response rates in the decitabine arm (N = 40) were as follows: complete or partial remission, 15 %; hematologic improvement, 15 %; resistant disease, 30 %. RAEBt patients in the decitabine arm had longer progression-free survival (PFS; hazard ratio (HR) 0.30, 95 % confidence interval (CI) 0.18-0.51; median, 6.2 vs 2.8 months) and overall survival (OS; HR 0.68, 95 % CI 0.42-1.11; median, 8.0 vs 6.0 months) than in the BSC arm (N = 35). Censoring at allogeneic hematopoietic stem cell transplantation, the OS difference between the treatment groups increased, particularly among patients aged 60-74 years (HR 0.48, 95 % CI 0.26-0.89). After regrouping the study cohort according to World Health Organization (WHO) criteria, patients with acute myeloid leukemia (AML) (i.e., ≥20 % blasts) in the decitabine arm (N = 27) also had longer PFS than in the BSC arm (N = 23) (HR 0.46, 95 % CI 0.26-0.83; median, 6.2 vs 2.8 months). In conclusion, 3-day decitabine displays clinical activity and efficacy in MDS and/or AML with 5-30 % blood or 20-30 % marrow blasts. [ABSTRACT FROM AUTHOR]

The faster hematopoietic recovery after autologous peripheral blood SCT (APBSCT) in patients with AML may be offset by an increased relapse risk as compared with autologous BMT (ABMT). The EORTC and GIMEMA Leukemia Groups conducted a trial (AML-10) in which they compared, as second randomization, APBSCT and ABMT in first CR patients without an HLA compatible donor. A total of 292 patients were randomized. The 5-year DFS rate was 41% in the APBSCT arm and 46% in the ABMT arm with a hazard ratio (HR) of 1.17; 95% confidence interval=0.85-1.59; P=0.34. The 5-year cumulative relapse incidence was 56% vs 49% (P=0.26), and the 5-year OS 50% and 55% (P=0.6) in the APBSCT and ABMT groups, respectively. APBSCT was associated with significantly faster recovery of neutrophils and platelets, shorter duration of hospitalization, reduced need of transfusion packed RBC and less days of intravenous antibiotics. In both treatment groups, higher numbers of mobilized CD34+ cells were associated with a significantly higher relapse risk irrespective of the treatment given after the mobilization. Randomization between APBSCT and ABMT did not result in significantly different outcomes in terms of DFS, OS and relapse incidence. [ABSTRACT FROM AUTHOR]

We report the chromosomal characteristics of a malignant teratoma with embryonal carcinoma component located in the pineal region of a 15-year-old boy. Chromosome analysis showed a near-triploid complex karyotype (62 chromosomes), including two copies of an isochromosome 12p, confirmed by fluorescence in situ hybridization analysis. The present findings indicate that isochromosome 12p formation is probably associated with the development of malignant germ cell tumours. [ABSTRACT FROM AUTHOR]

An obituary for Roland Berger, a French scientist and one of the pioneers in the cytogenetics field, is presented.

Myelodysplastic syndromes (MDS) represent a heterogeneous group of neoplastic hematopoietic disorders. Several recurrent chromosomal aberrations have been associated with MDS, but the genes affected have remained largely unknown. To identify relevant genetic lesions involved in the pathogenesis of MDS, we conducted SNP array–based genomic profiling and genomic sequencing in 102 individuals with MDS and identified acquired deletions and missense and nonsense mutations in the TET2 gene in 26% of these individuals. Using allele-specific assays, we detected TET2 mutations in most of the bone marrow cells (median 96%). In addition, the mutations were encountered in various lineages of differentiation including CD34+ progenitor cells, suggesting that TET2 mutations occur early during disease evolution. In healthy tissues, TET2 expression was shown to be elevated in hematopoietic cells with highest expression in granulocytes, in line with a function in myelopoiesis. We conclude that TET2 is the most frequently mutated gene in MDS known so far. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which offers a study on B-cell malignancies.

Chromosomal translocations represent an important prognostic indicator in B-cell chronic lymphocytic leukemia (B-CLL). However, their value had been neither determined in homogeneously treated patients nor compared to that of IgVH mutational status. Sixty-five B-CLL patients were investigated using cytogenetics, interphase fluorescence in situ hybridization (FISH), analysis of IgVH and of TP53 mutational status before treatment with 2-chloro-2′-deoxyadenosine (CdA). Translocations (n=45) were detected in 42% of the patients, including both balanced (n=12) and unbalanced (n=33) types. IgVH was mutated in 43% of the patients. Patients with translocations were more heavily pretreated (P=0.05), presented with more complex karyotypes (P<0.001), 17p abnormalities and TP53 mutations, and had a higher failure rate (59 vs 21% in patients without translocations, P=0.004). Patients with unbalanced translocations displayed a shorter median treatment-free survival (TFS, 6.9 vs 35.9 months, log rank 22.72, P<0.001) and overall survival (OS, 13.0 vs 68.0 months, log rank 16.51, P<0.001), as compared to patients without translocation. In multivariate analysis, unbalanced translocations were independently associated with therapeutic failure, short TFS and short OS. IgVH mutational status was independently associated with risk of failure and TFS, but not OS. In B-CLL patients treated with CdA, translocations are strong predictors of outcome.Leukemia (2007) 21, 1715–1722; doi:10.1038/sj.leu.2404764; published online 31 May 2007 [ABSTRACT FROM AUTHOR]

Multilineage dysplasia was advanced by the World Health Organization to increase prognostic accuracy in myelodysplastic syndromes (MDS) classification. We performed a structured cytomorphological examination of bone marrow (BM) in 221 low-grade MDS patients, this in conjunction with strict guidelines for cytopenias. A dysplasia scoring system was developed utilizing dysplastic changes, which were associated with worse outcome on univariate and multivariate analysis corrected for the International Prognostic Scoring System (IPSS). Dysplasia 10% in one BM lineage and one cytopenia constituted the low-risk category UCUD or Unilineage Cytopenia and Unilineage Dysplasia. The high-risk category comprised patients with cytopenia in 2 lineages and dysplasia in 2 BM lineages, namely MCMD or Multilineage Cytopenia and Multilineage Dysplasia. Intermediate-risk patients had one cytopenia and multilineage dysplasia, or cytopenia in 2 lineages and unilineage BM dysplasia, designated UCMD/MCUD or Unilineage Cytopenia and Multilineage Dysplasia/Multilineage Cytopenia and Unilineage Dysplasia. This system utilizing cytopenia–dysplasia scoring at diagnosis enabled comprehensive categorization of low-grade MDS cases that predicted for overall as well as leukemia-free survival. Cytopenia–dysplasia categorization added additional prognostic values to the lower risk IPSS categories. This suggests that a standardized dysplasia scoring system, used in conjunction with cytopenia, could improve diagnostic and prognostic sub-categorization of MDS patients.Leukemia (2007) 21, 668–677. doi:10.1038/sj.leu.2404564; published online 15 February 2007 [ABSTRACT FROM AUTHOR]

For long, T-cell acute lymphoblastic leukemia (T-ALL) remained in the shadow of precursor B-ALL because it was more seldom, and showed a normal karyotype in more than 50% of cases. The last decennia, intense research has been carried out on different fronts. On one side, development of normal thymocyte and its regulation mechanisms have been studied in multiple mouse models and subsequently validated. On the other side, molecular cytogenetics (fluorescence in situ hybridization) and mutation analysis revealed cytogenetically cryptic aberrations in almost all cases of T-ALL. Also, expression microarray analysis disclosed gene expression signatures that recapitulate specific stages of thymocyte development. Investigations are still very much actual, fed by the discovery of new genetic aberrations. In this review, we present a summary of the current cytogenetic changes associated with T-ALL. The genes deregulated by translocations or mutations appear to encode proteins that are also implicated in T-cell development, which prompted us to review the ‘normal’ and ‘leukemogenic’ functions of these transcription regulators. To conclude, we show that the paradigm of multistep leukemogenesis is very much applicable to T-ALL and that the different genetic insults collaborate to maintain self-renewal capacity, and induce proliferation and differentiation arrest of T-lymphoblasts. They also open perspectives for targeted therapies.Leukemia (2006) 20, 1496–1510. doi:10.1038/sj.leu.2404302; published online 6 July 2006 [ABSTRACT FROM AUTHOR]

Chromosomal aberrations of T-cell receptor (TCR) gene loci often involve the TCRαδ (14q11) locus and affect various known T-cell oncogenes. A systematic fluorescent in situ hybridization (FISH) screening for the detection of chromosomal aberrations involving the TCR loci, TCRαδ (14q11), TCRβ (7q34) and TCRγ (7p14), has not been conducted so far. Therefore, we initiated a screening of 126 T-cell acute lymphoblastic leukemia (T-ALL) and T-cell lymphoblastic lymphoma cases and 19 T-ALL cell lines using FISH break-apart assays for the different TCR loci. Genomic rearrangements of the TCRβ locus were detected in 24/126 cases (19%), most of which (58.3%) were not detected upon banding analysis. Breakpoints in the TCRαδ locus were detected in 22/126 cases (17.4%), whereas standard cytogenetics only detected 14 of these 22 cases. Cryptic TCRαδ/TCRβ chromosome aberrations were thus observed in 22 of 126 cases (17.4%). Some of these chromosome aberrations target new putative T-cell oncogenes at chromosome 11q24, 20p12 and 6q22. Five patients and one cell line carried chromosomal rearrangements affecting both TCRβ and TCRαδ loci. In conclusion, this study presents the first inventory of chromosomal rearrangements of TCR loci in T-ALL, revealing an unexpected high number of cryptic chromosomal rearrangements of the TCRβ locus and further broadening the spectrum of genes putatively implicated in T-cell oncogenesis.Leukemia (2006) 20, 1238–1244. doi:10.1038/sj.leu.2404243; published online 4 May 2006 [ABSTRACT FROM AUTHOR]

Presents a letter to the editor related to a study on gene rearrangements in acute leukemia.

The transcription factor Forkhead box protein P1 (FOXP1) is highly expressed in a proportion of diffuse large B-cell lymphoma (DLBCL). In this report, we provide cytogenetic and fluorescence in situ hybridization (FISH) data showing that FOXP1 (3p13) is recurrently targeted by chromosome translocations. The genomic rearrangement of FOXP1 was identified by FISH in three cases with a t(3;14)(p13;q32) involving the immunoglobulin heavy chain (IGH) locus, and in one case with a variant t(2;3) affecting sequences at 2q36. These aberrations were associated with strong expression of FOXP1 protein in tumor cells, as demonstrated by immunohistochemistry (IHC). The cases with t(3p13) were diagnosed as DLBCL ( × 1), gastric MALT lymphoma ( × 1) and B-cell non-Hodgkin's lymphoma, not otherwise specified ( × 2). Further IHC and FISH studies performed on 98 cases of DLBCL and 93 cases of extranodal marginal zone lymphoma showed a high expression of FOXP1 in approximately 13 and 12% of cases, respectively. None of these cases showed, however, FOXP1 rearrangements by FISH. However, over-representation of the FOXP1 locus found in one additional case of DLBCL may represent another potential mechanism underlying an increased expression of this gene.Leukemia (2005) 19, 1299–1305. doi:10.1038/sj.leu.2403813; published online 9 June 2005 [ABSTRACT FROM AUTHOR]

Presents a letter to the editor about the absence of prognostic value for CDKN2 deletions in childhood precursor-B acute lymphoblastic leukemia.

Although reciprocal chromosomal translocations are not typical for B-cell chronic lymphocytic leukemia (B-CLL), we identified the novel t(1;6)(p35.3;p25.2) in eight patients with this disorder. Interestingly, all cases showed lack of somatically mutated IgVH. Clinical, morphological, immunologic, and genetic features of these patients are described. Briefly, the age ranged from 33 to 81 years (median: 62.5 years) and the sex ratio was 6M:2F. Most of the patients (6/8) presented with advanced clinical stage. Therapy was required in seven cases. After a median follow-up of 28 months, five patients are alive and three died from disease evolution. Three cases developed transformation into diffuse large B-cell lymphoma. Translocation t(1;6) was found as the primary karyotypic abnormality in three patients. Additional chromosomal aberrations included changes frequently found in unmutated B-CLL, that is, del(11)(q), trisomy 12 and 17p aberrations. Fluorescence in situ hybridization analysis performed in seven cases allowed us to map the t(1;6) breakpoints to the 1p35.3 and 6p25.2 chromosomal bands, respectively. The latter breakpoint was located in the genomic region coding for MUM1/IRF4, one of the key regulators of lymphocyte development and proliferation, suggesting involvement of this gene in the t(1;6). Molecular characterization of the t(1;6)(p35.3;p25.2), exclusively found in unmutated subtype of B-CLL, is in progress.Leukemia (2005) 19, 77-82. doi:10.1038/sj.leu.2403543 Published online 28 October 2004 [ABSTRACT FROM AUTHOR]

Rhabdomyosarcomas are classified into three well-defined categories: embryonal, alveolar and pleomorphic rhabdomyosarcoma. Recently, seven cases of an unusual adult type of rhabdomyosarcoma with a prominent hyaline sclerosis have been described. We report the hitherto unreported cytogenetic changes of an adult sclerosing rhabdomyosarcoma. A 79-year-old woman underwent an amputation for a rapidly growing soft tissue mass in the anterior compartment of the right lower leg. The tumor infiltrated the tibia. On histology, a fascicular spindle to round cell proliferation, embedded in a prominent hyaline matrix, was seen. Immunohistochemistry showed focal desmin, myogenin and MyOD1 expression, and electron microscopy revealed Z-band material. Cytogenetic analysis disclosed a 44-49,XX,+del(1)(p22)[2],+11,+16[5],+18[12],+21[3],-22 [cp13] karyotype. Using fluorescent in situ hybridization (FISH) analysis, the tumor cells were negative for FOXO1A-disrupting translocations specific for alveolar rhabdomyosarcoma. The chromosomal composition of malignant cells resembled the pattern of numerical changes frequently observed in embryonal rhabdomyosarcoma, suggesting a close relationship of an adult sclerosing rhabdomyosarcoma with this entity. [ABSTRACT FROM AUTHOR]

Classical t(11;14)(q13;q32) involving IGH-CCND1 is typically associated with aggressive CD5-positive mantle cell lymphoma (MCL). Recently, we identified the 16K variant of this translocation, t(2;11)(pll;q13), in three patients with a leukemic small- cell B-non-Hodgkin lymphoma. In all cases, rearrangements of the 16K and CCND1 genes were demonstrated by fluorescence in situ hybridization. Moreover, we mapped the 11q13 break-point of this variant translocation in the 3′ region of CCND1 which contrasts with the 5′ breakpoints in a standard t(11;14)(q13;q32). Expression of cyclin Dl was shown in two cases analyzed either at diagnosis or during disease progression. All three patients were asymptomatic at presentation and no initial therapy was required. One patient died of a progressive disease 58 months from diagnosis, and two patients showed stable disease after 12 months of follow-up. In two analyzed cases, mutated 161/H genes were identified. Our findings indicate that variant t(2;11)(p11;q13) does not typify a classical MCL but possibly a more indolent leukemic lymphoma originating from an antigen experienced (mutated) B cell. [ABSTRACT FROM AUTHOR]

Circulating myeloid and lymphoid precursor dendritic cell (pDC) counts were determined in peripheral blood from 22 patients with myelodysplastic syndromes (MDS) by a single-platform flow cytometric protocol. The absolute count of myeloid and lymphoid pDC, as well as their relative number (as proportion of mononuclear cells or total leukocytes) was significantly lower in MDS (n=22) than in healthy controls (n=41). In 11 patients with chromosomal aberrations, purified pDC were examined by interphase fluorescence in situ hybridization. This revealed clonal involvement of myeloid as well as lymphoid pDC in all of them. These data therefore strongly suggest that myeloid and lymphoid pDC share a common precursor. Whether reduced peripheral blood counts of pDC contribute to the immunological abnormalities observed in MDS remains to be investigated.Leukemia (2004) 18, 1451-1456. doi:10.1038/sj.leu.2403430 Published online 29 July 2004 [ABSTRACT FROM AUTHOR]

A patient with mantle cell lymphoma (MCL) of the pleomorphic blastoid subtype is reported. The disease was clinically aggressive and refractory to chemotherapy, and the patient survived only 2 months. Cytogenetically, a t(11;19;14)(q13;q13;q32) was found. Fluorescent in situ hybridization (FISH) and molecular analyses demonstrated involvement of the BCL1/CCND1 locus in a three-way translocation. In addition, subclonal abnormalities of the region 8q24 manifested either as a t(8;22)(q24;q11)/CMYC rearrangement or trisomy 8 were identified. The pathogenetic impact of this very uncommon association of BCL1/CCND1 and CMYC rearrangements in MCL is discussed and the literature is reviewed. [ABSTRACT FROM AUTHOR]

Chromosomal rearrangements involving 3q26 either due to inversion or translocation with various partner chromosomes are a recurrent finding in malignant myeloid disorders. Typically, these chromosome aberrations contribute to ectopic expression of or to the formation of fusion genes involving the EVI1 proto-oncogene. Chromosomal translocations involving the short arm of chromosome 2 (p15-p23) and the distal part of the long arm of chromosome 3 (q26-q27) are a rare but recurrent finding in patients with myeloid malignancies, and are assumed to be part of this spectrum of disorders. Thus far, however, these translocations have been poorly studied. Here, we present 21 new cases with myelodysplasia, acute myeloid leukemia or CML in blast crisis, which upon karyotyping showed the presence of a t(2;3). Furthermore, an extensive literature review disclosed 29 additional cases. Morphological, clinical and cytogenetic assessment revealed the typical hallmarks of 3q26/EVI1 rearrangements, that is, trilineage dysplasia and dysmegakaryopoiesis, poor prognosis and additional monosomy 7. Molecular cytogenetic analysis and PCR in selected samples indicated that in most cases the translocation indeed targets the EVI1 locus. Mapping of the chromosome 2 breakpoints confirmed the initially suspected cytogenetic breakpoint heterogeneity at the 2p arm.Leukemia (2004) 18, 1108-1114. doi:10.1038/sj.leu.2403346 Published online 15 April 2004 [ABSTRACT FROM AUTHOR]

Detection of the FIP1L1-PDGFRA fusion gene or the corresponding cryptic 4q12 deletion supports the diagnosis of chronic eosinophilic leukemia (CEL) in patients with chronic hypereosinophilia. We retrospectively characterized 17 patients fulfilling WHO criteria for idiopathic hypereosinophilic syndrome (IHES) or CEL, using nested RT-PCR and interphase fluorescence in situ hybridization (FISH). Eight had FIP1L1-PDGFRA (+) CEL, three had FIP1L1-PDGFRA (-) CEL and six had IHES. FIP1L1-PDGFRA (+) CEL responded poorly to steroids, hydroxyurea or interferon-alpha, and had a high probability of eosinophilic endomyocarditis (n=4) and disease-related death (n=4). In FIP1L1-PDGFRA (+) CEL, palpable splenomegaly was present in 5/8 cases, serum vitamin B(12) was always markedly increased, and marrow biopsies revealed a distinctively myeloproliferative aspect. Imatinib induced rapid complete hematological responses in 4/4 treated FIP1L1-PDGFRA (+) cases, including one female, and complete molecular remission in 2/3 evaluable cases. In the female patient, 1 log reduction of FIP1L1-PDGFRA copy number was reached as by real-time quantitative PCR (RQ-PCR). Thus, correlating IHES/CEL genotype with phenotype, FIP1L1-PDGFRA (+) CEL emerges as a homogeneous clinicobiological entity, where imatinib can induce molecular remission. While RT-PCR and interphase FISH are equally valid diagnostic tools, the role of marrow biopsy in diagnosis and of RQ-PCR in disease and therapy monitoring needs further evaluation. [ABSTRACT FROM AUTHOR]

The recently discovered MLT/MALT1 gene is fused with the API2 gene in the t(11;18)(q21;q21), which characterizes about one-third of MALT lymphomas. In order to screen for variant translocations and amplifications of MLT/MALT1, we have developed a novel, undirected two-color interphase fluorescence in situ hybridization (FISH) assay with two PAC clones flanking MLT/MALT1. This assay was applied to 108 marginal zone B-cell lymphomas (MZBCLs), including 72 extranodal MALT lymphomas, 17 nodal, and 19 splenic MZBCL. In 19 MALT lymphomas (26%), but in none of the nodal or splenic MZBCL, separated hybridization signals of the MLT/MALT1 flanking probes, were found. Further FISH analyses showed that 12 of these 19 cases displayed the classical t(11;18) and the remaining seven cases revealed the novel t(14;18)(q32;q21), involving the MLT/MALT1 and IGH genes. The frequency at which these translocations occurred varied significantly with the primary location of disease. The t(11;18) was mainly detected in gastrointestinal MALT lymphomas, whereas the t(14;18) occurred in MALT lymphomas of the parotid gland and the conjunctiva. Amplification of MLT/MALT1 was not observed in any of the lymphomas analyzed. We conclude that the translocations t(11;18)(q21;q21) and t(14;18)(q21;q32) represent the main structural aberrations involving MLT/MALT1 in MALT lymphomas, whereas true amplifications of MLT/MALT1 occur rarely in MZBCL.Leukemia (2003) 17, 2225-2229. doi:10.1038/sj.leu.2403122 Published online 21 August 2003 [ABSTRACT FROM AUTHOR]

To accurately estimate the incidence of HOX11L2 expression, and determine the associated cytogenetic features, in T-cell acute lymphoblastic leukemia (T-ALL), the Groupe Français de Cytogénétique Hématologique (GFCH) carried out a retrospective study of both childhood and adult patients. In total, 364 patients were included (211 children ?15 years and 153 adults), and 67 (18.5%) [47 children (22.4%) and 20 adults (13.1%)] were shown to either harbor the t(5;14)q35;q32) translocation or express the HOX11L2 gene or both. Most of the common hematological parameters did not show significant differences within positive and negative populations, whereas the incidence of CD1a+/CD10+ and cytoplasmic CD3+ patients was significantly higher in positive than in negative children. Out of the 63 positive patients investigated by conventional cytogenetics, 32 exhibited normal karyotype, whereas the others 31 showed clonal chromosome abnormalities, which did not include classical T-ALL specific translocations. Involvement of the RANBP17/HOX11L2 locus was ascertained by fluorescence in situ hybridization in six variant or alternative (three-way translocation or cytogenetic partner other than 14q32) translocations out of the 223 patients. Our results also show that HOX11L2 expression essentially occurs as a result of a 5q35 rearrangement, but is not associated with another identified T-ALL specific recurrent genetic abnormality, such as SIL-TAL fusion or HOX11 expression.Leukemia (2003) 17, 1851-1857. doi:10.1038/sj.leu.2403061 [ABSTRACT FROM AUTHOR]

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[SUP+] 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[SUP+] 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... [ABSTRACT FROM AUTHOR]

Variable numbers of CD34[SUP+] cells can be harvested from the blood of AML patients in CR after G-CSF supported mobilization following consolidation chemotherapy. We hypothesized that a decreased ability to mobilize stem cells reflects a chemotherapy-induced reduction in the number of normal and leukemic stem cells. We therefore analyzed whether the mobilizing capacity of these patients was of prognostic significance. 342 AML-patients in first CR received daily G-CSF from day 20 of the consolidation course and underwent 1-6 aphereses to obtain a minimum dose of 2 × 10[SUP6] CD34[SUP+] cells/kg. Afterwards they were randomized for autologous bone marrow (BM) or blood SCT. As a surrogate marker for the mobilizing capacity, the highest yield of CD34[SUP+] cells of a single apheresis was adopted. Patients could be categorized into four groups: no harvest (n = 76), low yield (<1 × 10[SUP6] CD34[SUP+]/kg; n = 50), intermediate yield (1-6.9 × 10[SUP6] CD34[SUP+] cells/kg; n = 128) and high yield (≥7 × 10[SUP6] CD34[SUP+] cells/kg; n = 88). The median follow-up was 3.4 years; 163 relapses and 16 deaths in CR were reported. Autologous blood or BM SCT was performed in 36%, 64%, 81% and 88%, respectively, of the patients assigned to the no harvest, low, intermediate and high CD34[SUP+] yield group. The 3-year disease-free survival rate was 46.7%, 65.0%, 50.4% and 26.9% (P = 0.0002) and the relapse incidence was 47.5%, 30.1%, 43.1% and 71.9% (P < 0.0001). Multivariate Cox's proportional hazards model showed that the CD34[SUP+] yield was the most important independent prognostic variable (P = 0.005) after cytogenetics. Patients with the highest mobilizing capacity have a poor prognosis due to an increased relapse incidence. [ABSTRACT FROM AUTHOR]

A novel recurrent translocation t(11;14)(p11;q32) was found in three patients with splenic marginal zone B cell lymphoma (MZBCL). Fluorescence in situ hybridization (FISH) studies with IgH probes revealed in all cases involvement of the IgH locus, with breakpoint downstream of the IGVH sequences. Partner genes at 11p11 were not identified. The translocation defined the stem line in two patients, who carried additional cytogenetic aberrations, including a 17p deletion, present in both cases. In one patient a 7q- chromosome was the primary cytogenetic defect, the t(11;14) having been found in four out of 11 abnormal metaphase cells at the time of transformation into high-grade MZBCL. Hematological features in all cases included splenomegaly with peripheral blood (PB) involvement by a monoclonal B cell population consisting of lymphocytes with villous projections and several blast-like cells. The immunophenotype was CD19+; CD22bright+; CD23-, CD10-, CD5-, surface Igbright+. A bone biopsy in one patient revealed an interstitial infiltration with an intrasinusoidal pattern of growth. Histological studies on spleen specimens in two patients showed an expanded marginal zone, with small lymphocytes and several blast-like cells. One patient had a therapy-demanding disease, with partial, short-term responses to cytotoxic treatment; one patient transformed into a high-grade MZBCL involving the gut, the PB and the bone marrow 2 years after diagnosis; one patient was unresponsive to cytotoxic treatment and underwent splenectomy. The t(11;14)(p11;q32) may define a subset of splenic MZBCL with a high-grade component and a relatively aggressive clinical behavior. [ABSTRACT FROM AUTHOR]

Isotype-switch variants can easily be detected in a significant proportion of multiple myeloma (MM) patients. The biological significance of these isotype-switch variants remains obscure. Therefore, we studied the appearance of these isotype-switch variants in two murine MM models, 5T2MM and 5T33MM, both of IgG isotype. With a MM-specific PCR assay we could detect isotype-switch variants in the bone marrow of both the 5T2MM and the 5T33MM bearing mice, reflecting again the close resemblance of this mouse model to the human MM. These isotype-switch variants were not found in an in vitro stroma-independent variant of the 5T33MM line. However, when this 5T33MMvitro line was injected into young syngeneic mice, isotype-switch variants appeared thereafter in the isolated tumour cells. These isotype-switch variants could only originate from the MM-IgG expressing cell since IgG subclones from the 5T33MMvitro line again gave rise to isotype-switch variants. The appearance of IgA cells can be explained by down-stream switching of IgG to IgA, while the emergence of IgM cells have to occur via trans-switching to the sister chromatid as the Cmu region is deleted from the CIS-chromosome. This study demonstrates that isotype-switch variants originate from the major tumour clone suggesting no role for the MM-IgM expressing cell as a pre-switch precursor MM cell. The appearance of isotype-switch variants should be considered as a rare but normal event now becoming visible due to the high number of clonal cells present in MM. [ABSTRACT FROM AUTHOR]

The t(4;11) translocation is the cytogenetic hallmark of a subset of acute lymphoblastic leukemias characterized by pro-B immunophenotype and a dismal prognosis. This translocation fuses the MLL gene on chromosome band 11q23 and the AF4 gene on 4q21, resulting in the expression of fusion transcripts from both translocated chromosomes. The MLL-AF4 chimeric transcript is thought to mediate the leukemic transformation. The MLL genomic disruption detected by Southern blot and the RT-PCR for the MLL-AF4 chimeric transcript expression are molecular evidence of this chromosomal translocation. However, similar molecular rearrangements have also been identified in cases without the cytogenetic t(4;11). We report a 30-year-old patient with high risk ALL, a normal karyotype, and molecular evidence of MLL-AF4 fusion. Using a double color FISH assay with MLL specific PAC probes, a cryptic t(4;11) due to insertion of 5' MLL sequences in chromosome 4q21 was demonstrated. Consequently the MLL-AF4 was encoded by der(4). This insertion mechanism precludes the genomic recombination of AF4-MLL and supports the crucial role played by MLL-AF4 in leukemogenesis. The findings of our case, along with others, show the importance of complementing the karyotype with molecular and FISH techniques. [ABSTRACT FROM AUTHOR]

We collected peripheral blood stem cells (PBSC) in 19 early chronic phase CML patients following each of two consecutive cycles of intensive chemotherapy (CT) to evaluate whether an additional cycle of CT would increase Philadelphia (Ph)-negativity of the PBSC harvest. Autologous SCT (autoSCT) was performed if a major cytogenetic response (MCR) of the PBSC harvest was obtained. CT consisted of cytarabine 200 mg/ m2/day (days 1–7)/idarubicin 12 mg/m2/day (days 1–2) (cycle one) and cytarabine 2000 mg/m2/day (days 1–6)/amsacrine 120 mg/m2/day (days 1–3) (cycle two). One patient died of fungal pneumonia after the first cycle. Stem cells were harvested in 18 patients after cycle one and in 16 patients after cycle two. After the first cycle, all patients showed a cytogenetic response of their graft (MCR in eight patients: three complete, five partial), after cycle two, seven patients obtained an MCR (one complete, six partial). Seven patients became eligible for autoSCT. All patients proceeded with IFNα maintenance. Currently, 16 patients are alive. At the latest cytogenetic examination of bone marrow, four patients showed an MCR and four a minor response. In conclusion, although a second cycle of CT may contribute to elimination of leukemia residing in the patient, it appeared to be ineffective in improving the Ph-negativity of the PBSC graft. Bone Marrow Transplantation (2000) 25, 1147–1155. [ABSTRACT FROM AUTHOR]

Translocation t(12;21)(p13;q22) is the most frequent cytogenetic abnormality in childhood acute lymphoblastic leukemia (ALL) and is generally associated with favorable prognosis. In this report, we assessed the value of dual-color interphase fluorescence in situ hybridization (FISH) for the detection of t(12;21). Fifty-three patients were screened for ETV6/CBFA2 fusion by means of FISH, using two cosmid probes mapped on ETV6 and on CBFA2, respectively. The cut-off value (mean + three standard deviations) for positivity established on control patients was 9.3%. A comparison between FISH and molecular methods [reverse-transcriptase polymerase chain reaction/Southern blot (RT-PCR/SB)] was possible in 52 patients: 34 of 52 (65.4%) showed negative results with both approaches, and 13 of 52 (25%) were positive; 5 of 52 (9.6%) showed discrepancies: four patients who were positive using RT-PCR/SB were negative using FISH. Conversely, one patient negative when using RT-PCR/SB was positive with FISH. Further investigations on this patients, cytogenetically characterized by add(12p), showed an atypical breakpoint on ETV6, located 5' to the common breakpoint. Compared with RT-PCR and SB, dual-color interphase FISH with the cosmid probe set proved to be highly specific but showed limited sensitivity. [ABSTRACT FROM AUTHOR]

The value of dual-color fluorescence in situ hybridization (FISH) for the detection of inv(16), using two contigs of cosmid probes mapping on both sides of the chromosome 16p breakpoint region, was evaluated in 23 acute myeloid leukemias (AML) in different phases of the disease. At diagnosis interphase FISH detected inv(16) in 19/19 (100%) cases with conventional cytogenetics (CC) evident aberration and excluded the rearrangement in two patients with CC suspected inv(16). Moreover, it also identified an associated del(16p) in two patients. At relapse, it revealed the inv(16) in 8/8 (100%) studied cases. These results were concordant with those of reverse transcriptase-polymerase chain reaction (RT-PCR). From 13 patients who obtained at least one complete remission (CR), 31 follow-up samples were analyzed using interphase FISH. Twenty-nine specimens scored negative for inv(16) and two were positive. RT-PCR detected CBFbeta/MYH11 transcripts in four of the nine CR samples analyzed, being more sensitive than interphase FISH. Eight of the 13 patients relapsed at a median time of 6.5 months (range 1-15) from the last negative FISH analysis. Of the two patients with positive FISH in CR, one relapsed soon after. At diagnosis and relapse, interphase-FISH proved to be an effective technique for detecting inv(16) appearing more sensitive than CC. Prospective studies with more frequent controls and possibly additional FISH probes are needed to assess the value of interphase FISH for minimal residual disease (MRD) and relapse prediction. [ABSTRACT FROM AUTHOR]

The EU Concerted Action Workshop on 11q23 Abnormalities in Hematological Malignancies collected 550 patients with abnormalities involving 11q23. Of these, 53 patients had a translocation involving chromosome 11, breakpoint q23, and chromosome 19, breakpoint p13. Karyogram review enabled each patient to be further defined as t(11;19)(q23;p13.1) (21 patients) or t(11;19)(q23;p13.3) (32 patients). There was a marked difference between the type of banding and the translocation identified: t(11;19)(q23;p13.1) was detected predominantly by R-banding, whereas t(11;19)(q23;p13.3) was detected almost solely by G-banding. Additional change was extremely rare in patients with t(11;19)(q23;p13.1) but occurred in nearly half of the patients with t(11;19)(q23;p13.3). Patients with t(11;19)(q23;p13.1) all had leukemia of a myeloid lineage, mostly acute myeloid leukemia (AML), and were predominantly adult. In contrast patients with t(11;19)(q23;p13.3) had malignancies of both myeloid and lymphoid lineage and were mainly infants less than 1 year old. The survival of both groups of patients was generally poor, over 50% of t(11;19)(q23;p13.1) patients died within 2 years of diagnosis and the median survival of acute lymphoblastic leukemia (ALL) patients with t(11;19)(q23;p13.3) was 17.6 months. [ABSTRACT FROM AUTHOR]

The translocation (8;21) is a chromosome abnormality associated with acute myeloid leukemia (AML). As a consequence of the translocation the AML1 (CBFA2) gene in the 21q22 region is fused to the ETO(CDR,MTG8) gene in the 8q22 region, resulting in one transcriptionally active gene on the 8q- derivative chromosome. In this report we demonstrate the use of a highly specific dual-colour FISH method for the detection of t(8;21) on interphase cells. Genomic probes able to detect the chimeric AML1/ETO gene on the 8q- derivative chromosome were assayed on both normal and leukemic bone marrow and peripheral blood samples. Cut-off values were established by independent analysis of 15 bone marrow specimens negative for the translocation. The cut-off value of positive nuclei was determined to be 2% and the cut-off value for both positive nuclei and nuclei of uncertain classification, 4%. Persistence of cells above these cut-off values was interpreted as persistence of the mutated clone. A total of 36 samples at different disease stages were tested. Interphase cytogenetics detected the translocation at the onset and relapse in the BM or the PB of 14 AML patients with t(8;21). The technique appears to be an alternative tool to both conventional cytogenetics and reverse transcription polymerase chain reaction (RT-PCR) for the monitoring of disease during patients' follow-up. By enabling the analysis of individual cells, interphase FISH is ideal for clonality studies both for clinical and experimental applications. [ABSTRACT FROM AUTHOR]

Bone marrow from six patients with acute myeloid leukemia (AML) and t(8;21) (q22;q22) or a variant t(8;13;21) was studied by simultaneous analysis of cell morphology and karyotype. Combination of May-Grünwald-Giemsa (MGG) and fluorescence in situ hybridization (FISH) using probes specific for the breakpoint regions of chromosome 8 and 21 allowed us to establish the extent of cell-lineage involvement of the translocation. The translocation was found in all myeloid blasts and in high percentages of the more mature neutrophilic cells. In one patient we could demonstrate the translocation in the eosinophils as well. Erythroblasts and lymphocytes did not show the t(8;21) abnormality. These results indicate that the t(8;21) in AML is restricted to the myeloid (granulocytic) lineage. [ABSTRACT FROM AUTHOR]

In two androgen-dependent (FGC and P70) and two androgen-independent (LNO and R) sublines of the prostate cancer model LNCaP numerical and structural aberrations of chromosome 8 were investigated in detail. The techniques used were whole chromosome paint (WCP) and fluorescence in situ hybridization (FISH) with three cosmid probes mapping to different parts of the p-arm (D8S7 (8p23.3), LPL (8p22) and PLAT (8p11.1)). By WCP all four cell lines showed four copies of chromosome 8 in most cells. However, FISH demonstrated that in all sublines deletions in the 8p region were present. The majority of both FGC and P70 had two copies of cosmids D8S7 and LPL. The cosmid PLAT showed a broader distribution (1–4 copies), especially in P70. Compared with FGC and P70, both LNO and R showed a larger number of copies (3 or 4) of all three cosmid loci. It is discussed that this difference is probably the result of nondisjunction as a reaction to loss of other sequences on 8p, possibly the tumor suppressor gene (TSG) mapping to 8p21. The fact that both sublines LNO and R are androgen-independent raises the possibility of a link between TSG loss on 8p and androgen independence. [ABSTRACT FROM AUTHOR]

In order to analyze the efficiency of interphase FISH for the detection and monitoring of Ph+ cells in chronic myelogenous leukemia (CML) under interferon (IFN) treatment, the following experiments were performed: (1) 98 specimens derived from 32 patients were analyzed in parallel by dual-color FISH and by conventional chromosome analysis (CCA). A 300/200 kb BCR/ABL probe was used in all tests and a smaller 35.5/39 kb probe was tested in parallel in 22 BM samples; (2) 30 BM samples were prepared by direct harvest and by 24-h culture and were analyzed in parallel; (3) PB and BM samples obtained simultaneously from 11 patients were analyzed. The cut-off point for the recognition of BCR/ABL fusion was set at 2.4%, calculated as the mean percent of false positivity in 11 controls plus 3 s.d. A very close correlation was observed (r = 0.994, r2 = 0.988, P < 0.0001) between the percentages of ph+ cells as assessed by CCA and by interphase FISH in 98 samples (26 at diagnosis). There was a moderate overestimation of the frequency of Ph+ cells by FISH with respect to CCA, that was more evident at low-to-medium values of Ph positivity. Seven specimens without Ph+ metaphases (17–50 cells analyzed) were shown to carry 2.5–8% interphase cells with BCR/ABL fusion. Similar percentages of BCR/ABL+ nuclei were recorded in 22 samples hybridized using the 300/200 kb and the 35.5/39 kb probe-sets (variation range: 0–5%, mean 2.3%). A very good correlation between the frequency of Ph+ interphase cells was observed when analyzing in parallel BM preparations after direct harvest and after 24-h culture. Underestimation of the percentage of BCR/ABL+ cells was noted to occur in 2/11 PB samples, compared to BM samples, the remaining nine cases showing superimposable results at either sites. We arrived at the following conclusions: (1) dual-color FISH enables an accurate detection and monitoring of the size of the Ph-positive clone in CML at diagnosis and after IFN-therapy; (2) FISH is more accurate than CCA, especially at low levels of Ph-positive cells; (3) testing of directly harvested BM samples is feasible and accurate, giving the opportunity to perform centralized FISH analysis in the context of multicentre trials; (4) the percentage of BCR/ABL+ PB cells usually, though not invariably, reflects the frequency of mutated cells in the BM. [ABSTRACT FROM AUTHOR]

All four aged siblings (>80 years) of one family presented with B cell chronic lymphocytic leukemia (B-CLL). In an attempt to find common characteristics in the four patients, we performed detailed immunological marker analysis, Southern blot analysis of immunoglobulin (Ig) genes, and cytogenetic studies. In three patients clonality of the B-cells could be proven by single Ig light chain expression, but in the fourth patient no Ig light chain expression was detected and clonality of the B cells could only be demonstrated by Southern blot analysis of the Ig genes. Interestingly, in two patients, the Ig gene rearrangement patterns were compatible with the presence of two independent B cell clones, whereas in the two other siblings a monoclonal rearrangement pattern was found. All four patients showed clonal chromosome aberrations, which were different in each patient. In the two patients with biclonal Ig gene rearrangement patterns, two unrelated clones could also be demonstrated by the cytogenetic studies. These combined Ig gene and cytogenetic data indicate the presence of two different B-CLL in two of the four patients. Remarkably, the B-CLL cells of the two oldest patients expressed the CD8 antigen, which is rarely observed. Our finding of six different B-CLL in the four living siblings indicates that the members of this family are highly susceptible to the development of B-CLL. However we could not identify a common factor to explain this susceptibility further. In contrast to the literature, the occurrence of two B-CLL in one patient and the expression of CD8 were not associated with clinically aggressive disease in this family. [ABSTRACT FROM AUTHOR]