Clinical, immunophenotypic, and molecular profiling of trisomy 12 in chronic lymphocytic leukemia and comparison with other karyotypic subgroups defined by cytogenetic analysis

Multivariate transcriptome analysis identifies networks and key drivers of chronic lymphocytic leukemia relapse risk and patient survival

Background

Chronic lymphocytic leukemia (CLL) is an indolent heme malignancy characterized by the accumulation of CD5⁺ CD19⁺ B cells and episodes of relapse. The biological signaling that influence episodes of relapse in CLL are not fully described. Here, we identify gene networks associated with CLL relapse and survival risk.

Methods

Networks were investigated by using a novel weighted gene network co-expression analysis method and examining overrepresentation of upstream regulators and signaling pathways within co-expressed transcriptome modules across clinically annotated transcriptomes from CLL patients (N = 203). Gene Ontology analysis was used to identify biological functions overrepresented in each module. Differential Expression of modules and individual genes was assessed using an ANOVA (Binet Stage A and B relapsed patients) or T-test (SF3B1 mutations). The clinical relevance of biomarker candidates was evaluated using log-rank Kaplan Meier (survival and relapse interval) and ROC tests.

Results

Eight distinct modules (M2, M3, M4, M7, M9, M10, M11, M13) were significantly correlated with relapse and differentially expressed between relapsed and non-relapsed Binet Stage A CLL patients. The biological functions of modules positively correlated with relapse were carbohydrate and mRNA metabolism, whereas negatively correlated modules to relapse were protein translation associated. Additionally, M1, M3, M7, and M13 modules negatively correlated with overall survival. CLL biomarkers BTK, BCL2, and TP53 were co-expressed, while unmutated IGHV biomarker ZAP70 and cell survival-associated NOTCH1 were co-expressed in modules positively correlated with relapse and negatively correlated with survival days.

Conclusions

This study provides novel insights into CLL relapse biology and pathways associated with known and novel biomarkers for relapse and overall survival. The modules associated with relapse and overall survival represented both known and novel pathways associated with CLL pathogenesis and can be a resource for the CLL research community. The hub genes of these modules, e.g., ARHGAP27P2, C1S, CASC2, CLEC3B, CRY1, CXCR5, FUT5, MID1IP1, and URAHP, can be studied further as new therapeutic targets or clinical markers to predict CLL patient outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12920-021-01012-y.

Elevated Lactate Dehydrogenase Has Prognostic Relevance in Treatment-Naïve Patients Affected by Chronic Lymphocytic Leukemia with Trisomy 12

Chronic Lymphocytic Leukemia (CLL) patients with +12 have been reported to have specific clinical and biologic features. We performed an analysis of the association between demographic; clinical; laboratory; biologic features and outcome in CLL patients with +12 to identify parameters predictive of disease progression; time to treatment; and survival. The study included 487 treatment-naive CLL patients with +12 from 15 academic centers; diagnosed between January 2000 and July 2016; and 816 treatment-naïve patients with absence of Fluorescence In Situ Hybridization (FISH) abnormalities. A cohort of 250 patients with +12 CLL followed at a single US institution was used for external validation. In patients with +12; parameters associated with worse prognosis in the multivariate model were high Lactate DeHydrogenase (LDH) and β-2-microglobulin and unmutated immunoglobulin heavy-chain variable region gene (IGHV). CLL patients with +12 and high LDH levels showed a shorter Progression-Free-Survival (PFS) (30 months vs. 65 months; p < 0.001), Treatment-Free-Survival (TFS) (33 months vs. 69 months; p < 0.001), Overall Survival (OS) (131 months vs. 181 months; p < 0.001) and greater CLL-related mortality (29% vs. 11% at 10 years; p < 0.001) when compared with +12 CLL patients with normal LDH levels. The same differences were observed in the validation cohort. These data suggest that serum LDH levels can predict PFS; TFS; OS and CLL-specific survival in CLL patients with +12.

CD markers variations in chronic lymphocytic leukemia: New insights into prognosis

Chronic lymphocytic leukemia (CLL) is one of the most commonly occurring adult leukemias that is associated with clonal accumulation of mature apoptosis-resistant B-cells in bone marrow, peripheral blood, and specific tissues. Different pathogenesis factors can contribute to the aggression of the clinical course in this disease. Cytogenetic abnormalities and surface biomarkers of neoplastic CLL cells can be effective in the outcome of CLL, and the examination of changing CD markers expressions in the progression of CLL can be related to the prognosis of this disease. Changing expression levels of CD markers on lymphocytes and other cells in CLL patients can play a role in the aggressive clinical outcomes such as organomegaly, immunodeficiency, and advanced disease stages through their interaction with CLL microenvironment. Given the involvement of CD markers in the pathogenesis of CLL, it can be stated that recognizing the expression changes of CD markers in the cells involved in CLL can be a proper approach to evaluate prognosis among these patients.

[Clinical analysis of 70 chronic lymphocytic leukemia patients with trisomy 12 detected by FISH]

目的

总结探讨FISH检测12号染色体三体（CEP12）阳性慢性淋巴细胞白血病（CLL）患者的临床特征、治疗情况及预后。

方法

回顾性分析2003年5月至2015年4月接受FISH检测CEP12的330例CLL患者临床资料，比较CEP12阳性患者（70例）和CEP12阴性患者（260例）临床特征、疗效及预后差异。

结果

与CEP12阴性患者相比，CEP12阳性患者肝肿大（13.6%对4.0%，P=0.011）及LDH>247 U/L（43.3%对18.5%，χ²=15.892，P<0.001）比例更高，而发病年龄、性别、临床分期、β₂微球蛋白水平、IGHV突变比例及脾脏/淋巴结肿大等方面差异无统计学意义。CEP12阳性与阴性患者比较，FMC7阳性率更高（23.8%对12.7%，χ²=4.730，P=0.030），CD23阳性率更低（95.2%对99.6%，P=0.033）。氟达拉滨组、利妥昔单抗组、传统治疗组总有效率（ORR）分别为77.5%（31/40）、84.8%（56/66）、45.4%（50/110），差异有统计学意义，且传统治疗组ORR均低于氟达拉滨组及利妥昔单抗组；氟达拉滨组中CEP12阳性患者ORR低于CEP12阴性患者（42.9%对84.8%，P=0.034）；而利妥昔单抗组中CEP12阳性患者ORR高于CEP12阴性患者（91.7%对81.0%），但差异无统计学意义（P=0.306）。CEP12阳性患者中位诊断至起始治疗时间为22.6（95%CI 15.4~31.7）个月，中位总生存（OS）时间为118.5（95%CI 74.5~162.4）个月，5年无进展生存（PFS）及OS率分别为（52.9±7.6）%、（74.8±6.6）%。CEP12阳性与阴性患者比较，PFS（χ²=0.410，P=0.478）及OS（χ²=0.052，P=0.180）差异均无统计学意义。

结论

CEP12阳性CLL患者临床肝肿大及LDH增高更为常见，传统治疗疗效最差，单用氟达拉滨疗效不如CEP12阴性患者，但予含利妥昔单抗的治疗方案其疗效与CEP12阴性患者相当。

Mutational and cytogenetic analyses of 188 CLL patients with trisomy 12: A retrospective study from the French Innovative Leukemia Organization (FILO) working group

Trisomy 12 (tri12) is the second most frequent chromosomal aberration (15%-20%) in chronic lymphocytic leukemia (CLL). Tri12 confers an intermediate prognosis but is a heterogeneous entity. We examined whether additional mutational or chromosomal alterations might impact tri12 patient outcomes. This retrospective study, carried out by the French Innovative Leukemia Organization, included 188 tri12 patients with comprehensive information on immunoglobulin heavy chain (IGHV) gene status, karyotypic/FISH abnormalities, and NOTCH1, TP53, SF3B1, and MYD88 mutations. The main cytogenetic abnormalities associated with tri12 were del(13q) (25%), additional trisomies (14%) (including tri19 (10%) and tri18 (4%)), 14q32 translocations (10%), del(17p) (6.5%), del(14q) (4%), and del(11q) (4%). Unmutated (UM) IGHV, NOTCH1, and TP53, mutations were identified in respectively 66%, 25%, and 8.5% of cases. Multivariate analyses showed that additional trisomies (HR = 0.43, 95% CI = 0.23-0.78, P = .01) were associated with a significantly longer time to first treatment in Binet stage A patients and with a lower risk of relapse (HR = 0.37, 95% CI = 0.15-0.9, P = .03) in the overall tri12 population. Binet stage B/C, TP53 disruption, and UM IGHV status were associated with a shorter time to next treatment, while Binet stage B/C (HR = 4, 95% CI = 1.6-4.9, P = .002) and TP53 disruption (HR = 5, 95% CI = 1.94-12.66, P = .001) conferred shorter overall survival in multivariate comparisons. These data indicate that additional cytogenetic and mutational abnormalities, and particularly additional trisomies, IGHV status, and TP53 disruption, influence tri12 patient outcomes and could improve risk stratification in this population.

Morphological, immunophenotypic, and genetic features of chronic lymphocytic leukemia with trisomy 12: a comprehensive review

Chronic lymphocytic leukemia is an extremely heterogeneous disease and prognostic factors such as chromosomal abnormalities are important predictors of time to first treatment and survival. Trisomy 12 is the second most frequent aberration detected by fluorescence in situ hybridization at the time of diagnosis (10–25%), and it confers an intermediate prognostic risk, with a median time to first treatment of 33 months and a median overall survival of 114 months. Here, we review the unique morphological, immunophenotypic, and genetic characteristics of patients with chronic lymphocytic leukemia and trisomy 12. These patients carry a significantly higher expression of CD19, CD22, CD20, CD79b, CD24, CD27, CD38, CD49d, sIgM, sIgk, and sIgλ and lower expression of CD43 compared with patients with normal karyotype. Circulating cells show increased expression of the integrins CD11b, CD18, CD29, and ITGB7, and of the adhesion molecule CD323. Patients with chronic lymphocytic leukemia and trisomy 12 frequently have unmutated IGHV, ZAP-70 positivity, and closely homologous stereotyped B-cell receptors. They rarely show TP53 mutations but frequently have NOTCH1 mutations, which can be identified in up to 40% of those with a rapidly progressive clinical course.

Deciphering the molecular landscape in chronic lymphocytic leukemia: time frame of disease evolution

Dramatic advances in next generation sequencing technologies have provided a novel opportunity to understand the molecular genetics of chronic lymphocytic leukemia through the comprehensive detection of genetic lesions. While progress is being made in elucidating the clinical significance of recurrently mutated genes, layers of complexity have been added to our understanding of chronic lymphocytic leukemia pathogenesis in the guise of the molecular evolution and (sub)clonal architecture of the disease. As we prepare for an era of tailored therapy, we need to appreciate not only the effect mutations have on drug response but also the impact subclones containing specific mutations have at initial presentation, during therapy and upon relapse. Therefore, although the wealth of emerging genetic data has great potential in helping us devise strategies to improve the therapy and prognosis of patients, focused efforts will be required to follow disease evolution, particularly in the context of novel therapies, in order to translate this knowledge into clinical settings.

Incidence of chromosomal anomalies detected by interphase FISH in chronic lymphoid leukemia

Aims & methods: We used interphase FISH to determine the incidence of chromosomal changes in 638 B-cell chronic lymphocytic leukemia patients. Results: Chromosomal abnormalities were found in some 75% of the patients. Del(13)(q14) was present in 57.3 and 57% of patients at diagnosis and during follow-up, respectively. It was followed by trisomy 12 (19 and 19.8% at diagnosis and during follow-up, respectively), del(11)(q22) (9.1 and 14.3% at diagnosis and during follow-up, respectively) and del(17)(p13) (2.8 and 12.4% at diagnosis and during follow-up, respectively). Discussion & conclusion: Our results correlate with those obtained in 55 studies reported in the literature. Trisomy 12 and del(13)(q14) are present in high proportions at diagnosis and are not enriched during progression, to the contrary of del(11)(q22) and del(17)(p13) that are markers of evolution.

Genomic and Clinicopathologic Features of Primary Myelofibrosis With Isolated 13q Deletion

BACKGROUND

Primary myelofibrosis (PMF) is a rare myeloproliferative stem cell disorder. The genomic features in PMF are poorly understood. Characterization of genomic alternations in PMF helps to determine their association with clinicopathologic features for further therapeutic implications.

PATIENTS AND METHODS

In this retrospective study, we investigated genomic changes using array-based comparative genomic hybridization (aCGH) in 17 PMF patients with isolated del(13q) and confirmed our aCGH findings with quantitative polymerase chain reaction (PCR) assay. We also compared the clinicopathologic features of patients with del(13q) (n = 17) with those of patients with a normal karyotype (NK) (n = 26).

RESULTS

Clinicopathologically, del(13q) PMF patients had significantly higher blast counts (P = .03) than did NK patients, who had significantly higher marrow cellularity (P = .02). The degree of bone marrow fibrosis of PMF-3 was higher in the del(13q) group than in the NK group. Splenomegaly was present significantly more often in the del(13q) PMF group than in the NK group (P = .03). Genomically, the Janus Kinase 2 V617F mutation was observed less often in del(13q) PMF patients (P = .07). The common deleted region in del(13q) was confined to 13q13-13q14.3 according to G-band karyotyping, demonstrating a minimal deleted region (MDR) of 15.323 Mb, identified using aCGH. The tumor suppressor genes, Retinoblastoma, Forkhead box protein O1, and Succinyl -CoA ligase [ADP-forming] subunit beta in the MDR were deleted, confirmed using real-time PCR to confirm our aCGH findings.

CONCLUSION

Accurate molecular characterization of del(13q) in PMF using aCGH and quantitative PCR provided further insight to define the MDR and analyze the genomic changes in del(13q) PMF patients.

Second cancers and Richter transformation are the leading causes of death in patients with trisomy 12 chronic lymphocytic leukemia

BACKGROUND

Trisomy 12 (+12) is detected by fluorescence in-situ hybridization (FISH) analysis in up to 20% of patients with chronic lymphocytic leukemia (CLL). Patients with +12 are known to have unique features and to carry an intermediate prognosis.

PATIENTS AND METHODS

In order to better define this large group, we reviewed the characteristics of 250 untreated patients with +12.

RESULTS

When compared to 516 untreated patients negative for +12 by FISH, patients with +12 showed a higher incidence of thrombocytopenia, Richter transformation, and second malignant neoplasms (SMN), in addition to the expected increased rate of CD38 positivity and atypical immunophenotype. At a median follow-up of 51 months, 57% of patients needed first-line treatment; median time to first treatment was 38 months, and on multivariate analysis (MVA), it was found to be shorter in patients with advanced Rai stage, palpable splenomegaly, and deletion of 14q by conventional cytogenetic analysis. The overall response rate with first-line treatment was 94%. The median failure-free survival has not been reached, but on MVA, it was found to be shorter in patients whose disease responded in a manner other than complete remission or with FISH negativity for deletion 13q. The median overall survival for the entire group has not been reached, but MVA revealed it to be shorter in patients with an absolute lymphocyte count of > 30 × 10(9)/L or who developed SMN. Eighteen deaths have been observed so far, and Richter transformation and SMN were the leading causes of death (3 and 6, respectively).

CONCLUSION

Patients with +12 CLL show characteristic clinical and biologic features, and may benefit from increased surveillance for second cancers.

Genetic abnormalities in chronic lymphocytic leukemia: where we are and where we go

Chromosomal abnormalities in chronic lymphocytic leukemia (CLL) are detected in up to 80% of patients. Among them, deletions of 11q, 13q, 17p, and trisomy 12 have a known prognostic value and play an important role in CLL pathogenesis and evolution, determining patients outcome and therapeutic strategies. Standard methods used to identify these genomic aberrations include both conventional G-banding cytogenetics (CGC) and fluorescence in situ hybridization (FISH). Although FISH analyses have been implemented as the gold standard, CGC allows the identification of chromosomal translocations and complex karyotypes, the latest associated with poor outcome. Genomic arrays have a higher resolution that allows the detection of cryptic abnormalities, although these have not been fully implemented in routine laboratories. In the last years, next generation sequencing (NGS) methods have identified a wide range of gene mutations (e.g., TP53, NOTCH1, SF3B1, and BIRC3) which have improved our knowledge about CLL development, allowing us to refine both the prognostic subgroups and better therapeutic strategies. Clonal evolution has also recently arisen as a key point in CLL, integrating cytogenetic alterations and mutations in a dynamic model that improve our understanding about its clinical course and relapse.

Chromosomal translocations and karyotype complexity in chronic lymphocytic leukemia: a systematic reappraisal of classic cytogenetic data

The significance of chromosomal translocations (CTRAs) and karyotype complexity (KC) in chronic lymphocytic leukemia (CLL) remains uncertain. To gain insight into these issues, we evaluated a series of 1001 CLL cases with reliable classic cytogenetic data obtained within 6 months from diagnosis before any treatment. Overall, 320 cases were found to carry ≥ 1 CTRAs. The most frequent chromosome breakpoints were 13q, followed by 14q, 18q, 17q, and 17p; notably, CTRAs involving chromosome 13q showed a wide spectrum of translocation partners. KC (≥ 3 aberrations) was detected in 157 cases and significantly (P < 0.005) associated with unmutated IGHV genes and aberrations of chromosome 17p. Furthermore, it was identified as an independent prognostic factor for shorter time-to-first-treatment. CTRAs were assigned to two categories (i) CTRAs present in the context of KC, often with involvement of chromosome 17p aberrations, occurring mostly in CLL with unmutated IGHV genes; in such cases, we found that KC rather than the presence of CTRAs per se negatively impacts on survival; (ii) CTRAs in cases without KC, having limited if any impact on survival. On this evidence, we propose that all CTRAs in CLL are not equivalent but rather develop by different processes and are associated with distinct clonal behavior.

miR-29c down-regulation is associated with disease aggressiveness and poor survival in Chinese patients with chronic lymphocytic leukemia

Aberrant expression of microRNAs in chronic lymphocytic leukemia (CLL) has been reported to be associated with clinical outcome and improve prognostic stratification. The aim of this study was to explore the association of miR-29c expression with clinical parameters and survival in 53 Chinese patients with CLL. We showed that the miR-29c expression level decreased significantly from early to advanced clinical stages, and was significantly lower in patients with β(2)-microglobulin higher than 3.5 mg/L or with disease progression or death. With the cut-off determined by receiver operating characteristic (ROC) curve analysis, optimizing concordance with immunoglobulin heavy chain (IgVH) mutation status, miR-29c negative and positive groups were defined as including 17 and 36 patients, respectively. The miR-29c negative group had a higher percentage of patients with trisomy 12 or deletion of 11q or 17p (70.6% vs. 34.3%; p = 0.014) compared to the miR-29c positive group. The median progression-free survival and overall survival of the miR-29c negative group were 21 and 92 months, respectively, significantly shorter than in the miR-29c positive group (both not reached; p = 0.002 and p = 0.042, respectively), and miR-29c down-regulation was an independent prognostic factor for PFS. In conclusion, down-regulation of miR-29c is associated with higher tumor burden and significantly predicts short survival in Chinese patients with CLL.

MicroRNA-223 expression is uniformly down-regulated in B cell lymphoproliferative disorders and is associated with poor survival in patients with chronic lymphocytic leukemia

MicroRNA-223 (miR-223) expression has been demonstrated to be stage-specific in B cell differentiation and associated with the outcome of chronic lymphocytic leukemia (CLL). However, the expression pattern of miR-223 in B cell lymphoproliferative disorders and its association with the outcome of Chinese patients with CLL have not been investigated. In this study, we demonstrated that miR-223 expression was significantly decreased in CLL, mantle cell lymphoma (MCL) and splenic marginal zone lymphoma (SMZL). In CLL, miR-223 expression decreased significantly with progression from early to advanced clinical stages and was significantly lower in patients with elevated β(2)-microglobulin, unmutated immunoglobulin variable heavy chain (IgVH) gene or with disease progression or death. Using a cut-off determined by receiver operating characteristic (ROC) analysis optimizing concordance with IgVH mutational status, miR-223-negative and -positive groups were defined for 22 and 31 patients, respectively. The median progression-free survival (PFS) and overall survival of the miR-223-negative group were 13 and 40 months, respectively, significantly shorter than for the miR-223-positive group (both not reached; p = 0.002 and p = 0.018, respectively). Multivariate analysis revealed that the absence of miR-223 was the only independent factor capable of predicting shorter PFS. In conclusion, miR-223 is uniformly down-regulated in B-LPDs and is a useful prognostic factor for patients with CLL.

TOSO is overexpressed and correlated with disease progression in Chinese patients with chronic lymphocytic leukemia

Recently, a gene named TOSO was identified as being overexpressed and associated with the anti-apoptotic characteristic of chronic lymphocytic leukemia (CLL). However, the association of TOSO expression with clinical features of CLL has not been fully described, especially in Chinese patients. TOSO expression was detected by quantitative RT-PCR in CD19+ sorted cells in a cohort of 81 untreated patients with CLL. The results showed that the expression of TOSO in CLL was significantly higher than that in healthy controls (p = 0.027) and other B-cell lymphoproliferative diseases (p = 0.033). The expression level of TOSO was significantly correlated with Binet staging, IGVH mutation status, age, and time to treatment in CLL. A negative correlation was observed between age and TOSO expression (Spearman's, p = 0.025). No correlation was observed between the expression of TOSO and CD38 or ZAP-70. Cox regression analysis indicated that high expression of TOSO (more than 8.4) was an independent indicator for shorter treatment-free survival in CLL. We conclude that TOSO is specifically overexpressed and associated with progressive disease, and might be an important prognostic factor in CLL.

Dic(17;18)(p11.2;p11.2) is a recurring abnormality in chronic lymphocytic leukaemia associated with aggressive disease

Interphase cytogenetics are commonly used to identify clonal abnormalities in chronic lymphocytic leukemia (CLL) patients but fail to identify recurrent translocations that ultimately can direct more focused molecular characterization. Given the importance of del(17p13.1) in CLL outcome, we performed an extensive review of 1213 patients undergoing metaphase cytogenetics at our institution and identified 16 (1.3%) with a recurrent unbalanced translocation between the p arms of chromosomes 17 and 18 that results in a dicentric chromosome with loss of much of 17p and 18p. The dic(17;18)(p11.2;p11.2) was associated with a complex (three or more unrelated cytogenetic abnormalities) karyotype in 12 patients (75%) at the time that the abnormality was first identified, and eventually associated with a complex karyotype in 94% of patients. IGHV mutational analysis was un-mutated in 88% of cases where evaluation was possible. Except for one patient who was diagnosed with CLL incidentally during a workup for metastatic tonsillar cancer, all patients identified with dic(17;18)(p11.2;p11.2) met criteria for disease treatment, with a median time from diagnosis to first treatment of 15 months. Our data demonstrate that dic(17;18)(p11.2;p11.2) is a novel recurrent cytogenetic abnormality in CLL associated with early age at diagnosis and accelerated disease progression. Future efforts to identify genes disrupted by this translocation are warranted and ongoing.

The interface of Medicare coverage decision-making and emerging molecular-based laboratory testing

The process of obtaining Medicare coverage for clinical services (both at the national and local levels) can be complex and often leads to considerable confusion among external stakeholders. The entry of molecular diagnostic testing into the clinical arena of laboratory medicine has posed some special challenges, both for those providing the testing, and those paying for such technology. This commentary will seek to clarify Medicare's pursuit of defining medical necessity by describing both the local and national Medicare coverage policy processes. However, it should be understood that the Medicare reimbursement for such esoteric testing is a work-in-progress, without an established step-by-step process for obtaining a positive coverage decision. Yet, this evolving process provides all stakeholders (payers, laboratories, industry, clinicians, etc.) with an opportunity to fully understand the health policy implications of complex molecular diagnostic testing. In addition, brief case study vignettes are incorporated into our discussion, to show how laboratorians, in conjunction with their clinical colleagues, can effectively engage the payer community in developing more medically sound and fiscally responsible coverage policies.

Karyotype-specific microRNA signature in chronic lymphocytic leukemia

Chromosomal abnormalities, immunoglobulin heavy chain variable-region (IGHV) gene mutation status, and zeta-associated protein 70 (ZAP-70) expression levels have independent prognostic relevance in chronic lymphocytic leukemia (CLL); however, their concordance is variable. Because deregulation of microRNAs has been linked to disease initiation and progression in CLL, we studied the value of the microRNAs as a signature for CLL patients with specific chromosomal abnormalities. We identified 32 microRNAs able to discriminate the 11q deletion, 17p deletion, trisomy 12, 13q deletion, and normal karyotype cytogenetic subgroups. The expression values of 9 among the 32 microRNAs (miR-151-3p, miR-34a, miR-29c, miR-29b, miR-155, miR-148a, miR-146a, miR-146b5p, and miR-640) were correlated with gene expression data from the same samples to assess their biologic impact on CLL. In this study we also found that IGHV unmutated, high expression of ZAP-70 protein, and low expression of the miR-223, miR-29c, miR-29b, and miR-181 family were strongly associated with disease progression in CLL cases harboring 17p deletion, whereas in those harboring trisomy 12 only high expression of the miR-181a, among the analyzed parameters, suggested more aggressive disease. Thus, the use of the microRNA-based classifications may yield clinically useful biomarkers of tumor behavior in CLL.

Coexistence of trisomy 12 and del(13)(q14.3) in two patients with chronic lymphocytic leukemia

We describe two patients with diagnosis of chronic lymphocytic leukemia (CLL) in whom interphase fluo?rescence in situ hybridization (FISH) analysis revealed trisomy 12 and del(13)(q14.3) occurring in the same clone. These abnormalities are rarely seen together and the prognostic relevance of their coexistence is still unclear. According to some data, a probable adverse prognosis for this group of patients is suggested. Our patients have been in a stable phase of the disease for more than one year since the given abnormalities were documented in their karyotypes. Further study is necessary to determine the prognostic significance of coexistence of these abnormalities in CLL patients.

Cytogenetic characterisation in Chinese patients with chronic lymphocytic leukemia: a prospective, multicenter study on 143 cases analysed with interphase fluorescence in situ hybridisation

Chronic lymphocytic leukemia (CLL) is infrequent in Chinese people. Conventional cytogenetic analysis underestimates the frequency of chromosome aberrations in CLL due to the low rate of spontaneous mitoses. The aim of this study was to prospectively explore the frequency of chromosomal abnormalities in Chinese patients with CLL using interphase fluorescence in situ hybridisation (FISH) and probes for 12 centromere, 13q14, 14q32, 17p13, 11q22 and 6q23 on 143 patients with CLL. Molecular cytogenetic aberrations were found in 104 patients (72.7%) and 40 patients (28.0%) with more than two abnormalities. The most frequent abnormality was del(13q14) (47.6%), followed by trisomy 12 (21.7%), 14q32 translocation (19.6%), del(17p13) (12.6%), del(11q22) (11.9%) and del(6q23) (4.9%), respectively. The percentages of patients with aberrations by FISH were 75.4%, 72.3% and 67.7% for Binet stages A, B and C, respectively. In early stage (Binet A), del(13q14) aberration was more frequent than in Binet B and C (61.5% vs. 31.9% and 41.9%) (P=0.021). Patients with advanced stage (Binet C) had more frequent del(17p13) aberration than in Binet A and B (32.3% vs. 9.2% and 4.3%) (P=0.008). It was showed that the frequencies of the chromosomal abnormalities in our study population were similar to the frequencies in Western countries.

Impact of trisomy 12, del(13q), del(17p), and del(11q) on the immunophenotype, DNA ploidy status, and proliferative rate of leukemic B-cells in chronic lymphocytic leukemia

B-cell chronic lymphocytic leukemia (B-CLL) is a well-defined clinical entity with heterogeneous molecular and cytogenetic features. Here, we analyze the impact of trisomy 12, del(13q), del(17p), and del(11q) as determined by interphase fluorescence in situ hybridization analysis of purified neoplastic B-CLL cells on their immunophenotype, DNA ploidy status and proliferative rate.Overall, 111 of 180 (62%) B-CLL cases studied displayed one (50%) or more (12%) genetic abnormalities, del(13q) (35%) being more frequently detected than trisomy 12 (23%) followed by del(11q) (9%) and del(17p) (8%). Trisomy 12 was associated with a higher frequency of DNA aneuploidy, stronger expression of CD19, CD20, CD22, CD24, CD27, CD79b, CD38, and sIg and lower reactivity for CD43 with respect to cytogenetically nonaltered cases. In turn, cases with del(13q) displayed greater reactivity for CD20, FMC7, CD27, CD22, CD5, and bcl2, while del(11q) was associated with brighter expression of CD38, FMC7, CD25, and sIg. Hierarchical clustering analysis of the immunophenotype of B-CLL cases with cytogenetic abnormalities allowed the identification of three different groups of patients with increasing frequencies of trisomy 12, del(11q), and del(13q). Remarkably, none of the cytogenetic abnormalities analyzed except coexistence of 13q- and 17p- had a clear impact on the proliferative index of B-CLL cells.