Interphase cytogenetic analysis in Argentinean B-cell chronic lymphocytic leukemia patients: association of trisomy 12 and del(13q14)

Induction of chronic lymphocytic leukemia-like disease in STYK1/NOK transgenic mice

STYK1/NOK functions in a ligand independent and constitutive fashion to provoke tumor formation and to be up-regulated in many types of cancer cells. However, how STYK1/NOK functions at the whole animal level is completely unknown. Here, we found that STYK1/NOK-transgenic (tg) mice spontaneously developed immunosuppressive B-CLL-like disease with generally shorter life spans. The phenotype of STYK1/NOK-induced B-CLL was typically heterogeneous, and most often, presented lymphadenectasis accompanied with hepatomegaly and/or splenomegaly. STYK1/NOK-tg mice also suffered reduced immune responses. The expanded CD5⁺CD19⁺ (B1) lymphocyte pool was detected within peripheral lymphoid organs. Analysis on GEO profile revealed that expression of STYK1/NOK were significantly up-regulated in primary human B-CLL. Inoculation of blood cells from sick STYK1/NOK-tg mice into immune-deficient recipients recaptured the B1 malignant phenotype. Our study demonstrated that STYK1/NOK transgenic mouse may serve as a useful model system for the developments of novel diagnosis and treatment of B-CLL.

Role of cytogenetic abnormalities detected by fluorescence in situ hybridization as a prognostic marker: Pathogenesis & clinical course in patients with B-chronic lymphocytic leukaemia

Background & objectives:

B-cell chronic lymphocytic leukaemia (B-CLL) is one of the most common forms of adult leukaemia, with a highly variable clinical course. Specific chromosomal and genetic aberrations are used clinically to predict prognosis, independent from conventional clinical markers. Molecular cytogenetic methods such as fluorescence in situ hybridization (FISH) detect aberrations in up to 80 per cent B-CLL patients. This study was conducted to score the frequencies of recurrent aberrations, i.e., del(13q14), trisomy 12, del(11q22), del(17p13), del(6q21) and IgH (immunoglobulin heavy chain) translocations and to understand their role in prognostication and risk stratification.

Methods:

FISH studies were performed on bone marrow aspirate or peripheral blood of 280 patients using commercially available disease-specific probe set. The data were correlated with clinical and haematological parameters such as low haemoglobin, splenomegaly and lymphadenopathy.

Results:

Chromosomal aberrations were detected in 79 per cent of patients, with del(13q14) (57%) as the most common cytogenetic aberration, followed by trisomy 12 (27%), del(11q22) (22%), t(14q32) (19%), del(17p13) (18%) and del(6q21) (9%). Single or in coexistence with other aberration del(13q14) had a favourable outcome in comparison to del(11q22), t(14q32), del(17p13) and del(6q21) which were associated with advanced stages of the disease. Trisomy 12 had a variable clinical course.

Interpretation & conclusions:

FISH was found to be a sensitive and efficient technique in detecting the prevalence of recurrent cytogenetic abnormalities. Each of these aberrations is an important independent predictor of disease progression and survival which aids in designing risk-adapted treatment strategies for better disease management.

Chronic lymphocytic leukemia: a clinical review including Korean cohorts

Only 5th decade ago, chronic lymphocytic leukemia (CLL) was only recognized as disease group of presenting features like peripheral lymphocytosis, organomegaly including of splenomegaly. As understanding of disease biology and molecular diagnostic tools are getting improved gradually, characterization of variation in CLL's clinical courses was facilitated, resulting in better risk stratification and targeted treatments. Consequently multiple new targeted agents have been used in treatment of CLL, it makes improved clinical outcome. Rituximab containing chemoimmunotherapy (combination of rituximab, fludarabine, and cyclophosphamide) have shown better overall response rate and progression-free survival on fit patients' group in front-line setting, result in standard first-line therapeutic option for CLL. Furthermore, after introducing that the B-cell receptor is crucial for the evolution and progression of CLL, emerging treatments targeting highly activated surface antigens and oncogenic signaling pathways have been associated with several successes in recent decades. These include new anti-CD 20 monoclonal antibody (obinutuzumab), the bruton tyrosine kinase inhibitor (ibrutinib), the phosphatidylinositol 3-kinase inhibitor (idelalisib), and B-cell CLL/lymphoma 2 inhibitor (ABT-199 and ABT-263). So, we discuss not only general pathophysiology of CLL, but also rapidly advancing treatment strategies that are being studied or approved for treatment of CLL.

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.

Validation of Western common recurrent chromosomal aberrations in Korean chronic lymphocytic leukaemia patients with very low incidence

In Asia, the incidence of chronic lymphocytic leukaemia (CLL) is lower than in Western countries. Only a few studies of CLL have been conducted in Korea, and no long-term clinical outcome data are available. We assessed the frequency of common chromosomal aberrations in Korean CLL patients using interphase fluorescence in situ hybridization (FISH) and investigated their relationship to clinical outcomes. Between 2000 and 2011, conventional cytogenetic studies were performed in 58 patients, and FISH results were available in 48 patients. We used six DNA probes for the detection of del(13q14), trisomy 12, del(11q22), del(17p13), IGH rearrangement and del(6q23). Chromosomal aberrations were identified in 15 of 58 patients (26%) with conventional cytogenetic studies and in 25 of 48 patients (52%) with interphase FISH, including six patients with complex karyotypes. In contrast with the results of Western studies, trisomy 12 was the most common aberration, followed by IGH rearrangement, del(13q14), del(11q22) and del(17p13). Deletion of 6q23 was not observed, and isolated del(13q14) was less frequent than in Western studies. Compared with the other types of chromosomal aberrations, patients with del(11q22) and del(17p13) were more likely to be Rai stage 3-4 and Binet stage C, resulting in poor responses to chemotherapy and worse outcomes. In contrast, patient with trisomy 12 and isolated del(13q14) showed better responses and superior survival outcomes. The incidence of CLL is lower in Korea than in Western countries, and the frequency of chromosomal aberrations differs, perhaps reflecting differences in the pathogenic mechanism between ethnicities. Large prospective studies are needed to further assess the prognostic value of these results in Korean CLL patients.

FISH Analysis for del6q21 and del17p13 in B-cell Chronic Lymphocytic Leukemia in Iranians

BACKGROUND

B-cell chronic lymphocytic leukemia (B-CLL) is the most common leukemia in the Western world. Major progress has been made in assessing typical chromosomal abnormalities and recognition of the correlation of these chromosomal abnormalities with laboratory features and clinical course of the disease. The most frequent genomic changes are deletions at 13q14, 11q22-23 and 17p13 and trisomy of chromosome 12.

OBJECTIVES

The aim of this study was to investigate the frequency of chromosomal aberrations in B-CLL patients' peripheral blood and/or bone marrow using a molecular cytogenetic method, interphase fluorescence in situ hybridization (I-FISH) and to evaluate the correlation between these genomic changes and clinical findings.

PATIENTS AND METHODS

I-FISH analyses were performed on bone marrow and blood samples of 66 B-CLL patients.

RESULTS

Deletion of 17p13 was found in 11 (16.6%) and deletion 6q21 was present in 5 (7.5%). Statistical analyses were performed to investigate the correlation of these molecular-cytogenetic findings with family history, Rai staging and CD38 marker. No clear differences in distribution was noted for del17p13 and del6q21 among patients with and without family history, and no direct correlation was noted between these genomic changes and CD38 marker, but the correlation of del17p13 and Rai stage was significant. There was a high frequency of Rai stage II within del17p13 patients.

CONCLUSIONS

It was demonstrated that the presence of del6q21 in B-CLL patients indicates poor prognosis and on the contrary, presence of del17p13 points at the good prognostic value of the disease.

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.

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.

Detection of chromosomal abnormalities in chronic lymphocytic leukemia increased by interphase fluorescence in situ hybridization in tetradecanoylphorbol acetate–stimulated peripheral blood cells

Interphase fluorescent in situ hybridization on unstimulated peripheral blood mononuclear cells (I-FISH-PBMC) is used to detect chromosomal abnormalities such as 11q-, 13q-, 17p-, and trisomy 12 in chronic lymphocytic leukemia (CLL). A total of 56 samples from 49 patients with CLL were studied using commercially available probes for chromosome regions 11q22.3 (ATM), 13q14 (13S272), 17p13 (p53) and 12 centromere (D12Z3). We compared the results obtained with I-FISH-PBMC and those with I-FISH on TPA (tetradecanoylphorbol acetate; phorbol-12-myristate-13-acetate) stimulated peripheral blood cells (I-FISH-TPA) used for conventional cytogenetics, to evaluate the usefulness of I-FISH-TPA. The proportion of abnormal nuclei obtained with the I-FISH-TPA was higher than that found with I-FISH-PBMC (P < 0.001). Consequently, 15 cases with a negative or borderline result with I-FISH-PBMC became positive with I-FISH-TPA for 11q- (n = 2), 13q- (n = 9), and trisomy 12 (n = 4). In all but one of these, chromosomal abnormalities were confirmed by either metaphase FISH or conventional G-banding. Detection of cytogenetic aberrations thus increased from 51% with I-FISH-PBMC to 78% with I-FISH-TPA. Notably, all 15 of the cases that reached the diagnostic thresholds for 11q-, 13q-, and trisomy 12 had a slight lymphocytosis. An absolute lymphocyte count <8.7 x 10(9)/L was found to be the critical threshold (P = 0.037) below which I-FISH-TPA rather than I-FISH-PBMC should be performed. Not only could I-FISH-TPA detect a higher proportion of abnormal interphase nuclei, but it could also identify abnormal CLL cases that might be overlooked with use of I-FISH-PBMC, especially those with low absolute lymphocyte counts. I-FISH-TPA is thus a reliable technique for clinical diagnostics in CLL.

[Complex analysis of prognostic factors in chronic lymphocytic leukemia]

INTRODUCTION

Many new prognostic factors established in recent years in chronic lymphocytic leukemia. May help predicting survival.

AIMS

The goal of the present study was to determine the frequency and the correlation of these novel prognostic factors in samples of 419 leukemia patients.

METHODS

The mutation status of the IgH gene was evaluated in 160 cases.

RESULTS

In 62% of cases, non-mutated IgH gene was found, the heavy chain family usage was different in mutated and non-mutated cases. The CD38 expression demonstrated 78% concordance with the mutation status, the ZAP-70 expression failed to show any correlation. Cytogenetic abnormalities were seen in 76% of cases, the most frequent were del(13q) (57%), trisomy 12 (15%), del(11q) (12%) and del(17p) (6%). 95% of cases with del(11q) harbored non-mutated, 74% of cases with del(13q) as the sole anomaly demonstrated mutated IgH genes.

CONCLUSIONS

The parameters analysed are not independent of each other, utilization of them in the clinical routine needs careful planning.

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

In a cohort of 130 unselected chronic lymphocytic leukemia (CLL) patients, 73 cases had normal karyotypes, 57 cases had abnormal karyotypes, and 22/57 cases carried more than one abnormality. Trisomy 12 (+12) was the most common abnormality (26/130 cases; 20%), and 17/26 cases had isolated +12. Del(13q)/t13q/-13 was detected in 19/130 cases (14.6%), and 5/19 cases had isolated del(13)(q12q14). Deletion (11)(q23) and del(17p)/-17 were detected in 5/130 cases, respectively. CD38 expression was significantly more frequent in the +12/11q/17p versus the normal/del(13q) subgroups. A significant association was detected between +12 and FMC7 positivity. IGHV-unmutated cases were significantly more frequent in the +12/11q/17p subgroups. Patients with normal karyotype/del(13q) had a longer median time to progression versus the patients in the +12/11q/17p subgroups. According to multivariate analysis, only IGHV mutation status remained a statistically significant variable for progression-free survival (PFS). Furthermore, IGHV mutation status and clinical stage at diagnosis were the only significant prognostic factors for overall survival. Among Binet-A patients, significant parameters for shorter PFS were +12 or 11q/17p aberrations, CD38 expression, and IGHV unmutated status. In multivariate analysis, only CD38 expression and IGHV-unmutated status retained statistical significance for PFS. In conclusion, trisomy 12 in CLL is characterized by considerable heterogeneity and seems to be associated with disease progression.

Korean patients with chronic lymphocytic leukemia show the similar types of chromosomal aberrations as those in Europe and North America

Chronic lymphocytic leukemia (CLL) is frequent in the West, but rare in Korea. In this study, the frequency of chromosome aberration in Korean CLL patients was examined by applying interphase fluorescence in situ hybridization (FISH). Conventional cytogenetic test and FISH were performed on bone marrow aspirates obtained from 16 CLL patients. By applying DNA probes (Vysis, Downers Grove, IL, USA), the deletion in 11q22-23, 13q14, 13q34, and 17p13, and trisomy 12 were examined. With FISH, molecular cytogenetic aberration was detected in 10 of 16 patients [63%, 95% confidence interval (CI) 39-86], whereas with conventional cytogenetic test, chromosomal aberration was detected only in 2 out of 13 cases (15%, 95% CI 0-35). In total, the cases with one or more chromosomal aberrations were 11 out of 16 cases (69%, 95% CI 46-92). The most frequently detected aberration was the 13q14 deletion (69%, 95% CI 44-94), followed by trisomy 12 (19%, 95% CI 0-38) and 11q22 deletion (14%, 95% CI 0-33). No deletion in 17p13 was observed. In conclusion, CLL in Korean is a heterogeneous genetic disorder, showing similar genetic changes in Europe and North America.

Incidence of chromosomal anomalies detected with FISH and their clinical correlations in B-chronic lymphocytic leukemia

B-chronic lymphocytic leukemia (B-CLL) is the most common adult leukemia. Molecular genetic characterization of B-CLL has made significant progress and typical chromosomal anomalies have been assessed. The most frequent chromosomal abnormalities are deletions at 13q14, 17p13, and 11q22 approximately q23 and trisomy 12. The aim of this study was to establish incidence of chromosomal changes in bone marrow or peripheral blood cells (or both) of B-CLL patients using a molecular cytogenetic method, interphase fluorescence in situ hybridization (I-FISH), and to evaluate the prognostic implications. We performed I-FISH on bone marrow and blood smears from 217 B-CLL patients (124 male, 93 female). Trisomy 12 was found in 35 of the 217 (16%); deletion 13q14 was analyzed in 207 patients and found in 112 (54%). Deletion 17p13 was found in 34 (16%) out of 206 examined. Deletion of 11q23 was analyzed in 56 patients and was present in 7 (12%). Statistical analyses were performed to correlate the molecular-cytogenetic findings with disease status (stable versus progressive), Rai stage, CD38/CD19 antigen coexpression, immunoglobulin variable heavy chain (IgV(H)) mutational pattern, and other clinical and laboratory parameters. No apparent differences in distribution were noted for anomalies +12, del(13)(q14), or del(17)(p13) among patients with stable and progressive disease, and no consistent pattern in the distribution of type of genomic changes were found among various Rai stages and in CD38/CD19-positive or -negative patients. Patients without IgV(H) mutation had a worse prognosis; however, distribution of chromosomal abnormalities identified with FISH was the same for patients with and without IgV(H) mutations.