Patients with chronic lymphocytic leukaemia and clonal deletion of both 17p13.1 and 11q22.3 have a very poor prognosis

Atypical Lipomatous Tumor Originating From the Nasopharynx in a Patient with Chronic Lymphocytic Leukemia

Atypical lipomatous tumor, also known as well-differentiated liposarcoma, is rare in the head and neck region. The primary and most effective option in the treatment of this malignancy with a good prognosis is excision with clean surgical margins. Therefore, it is important to distinguish this malignancy from lesions that require more aggressive treatment. In this article, we present the case of an atypical lipomatous tumor originating from the nasopharynx and almost completely obstructing the oropharynx in a 38-year-old male patient with chronic lymphocytic leukemia. To the best of our knowledge, this is the first report in the literature of an atypical lipomatous tumor case originating from the nasopharynx.

Small Non-Coding RNAs in Leukemia

In 2020, more than 60,500 people were diagnosed with leukemia in the USA, and more than 23,000 died. The incidence of leukemia is still rising, and drug resistance development is a serious concern for patients' wellbeing and survival. In the past two decades, small non-coding RNAs have been studied to evaluate their functions and possible role in cancer pathogenesis. Small non-coding RNAs are short RNA molecules involved in several cellular processes by regulating the expression of genes. An increasing body of evidence collected by many independent studies shows that the expression of these molecules is tissue specific, and that their dysregulation alters the expression of genes involved in tumor development, progression and drug response. Indeed, small non-coding RNAs play a pivotal role in the onset, staging, relapse and drug response of hematological malignancies and cancers in general. These findings strongly suggest that small non-coding RNAs could function as biomarkers and possible targets for therapy. Thus, in this review, we summarize the regulatory mechanisms of small non-coding RNA expression in different types of leukemia and assess their potential clinical implications.

Dissecting the role of TP53 alterations in del(11q) chronic lymphocytic leukemia

BACKGROUND

Several genetic alterations have been identified as driver events in chronic lymphocytic leukemia (CLL) pathogenesis and oncogenic evolution. Concurrent driver alterations usually coexist within the same tumoral clone, but how the cooperation of multiple genomic abnormalities contributes to disease progression remains poorly understood. Specifically, the biological and clinical consequences of concurrent high-risk alterations such as del(11q)/ATM-mutations and del(17p)/TP53-mutations have not been established.

METHODS

We integrated next-generation sequencing (NGS) and clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 techniques to characterize the in vitro and in vivo effects of concurrent monoallelic or biallelic ATM and/or TP53 alterations in CLL prognosis, clonal evolution, and therapy response.

RESULTS

Targeted sequencing analysis of the co-occurrence of high-risk alterations in 271 CLLs revealed that biallelic inactivation of both ATM and TP53 was mutually exclusive, whereas monoallelic del(11q) and TP53 alterations significantly co-occurred in a subset of CLL patients with a highly adverse clinical outcome. We determined the biological effects of combined del(11q), ATM and/or TP53 mutations in CRISPR/Cas9-edited CLL cell lines. Our results showed that the combination of monoallelic del(11q) and TP53 mutations in CLL cells led to a clonal advantage in vitro and in in vivo clonal competition experiments, whereas CLL cells harboring biallelic ATM and TP53 loss failed to compete in in vivo xenotransplants. Furthermore, we demonstrated that CLL cell lines harboring del(11q) and TP53 mutations show only partial responses to B cell receptor signaling inhibitors, but may potentially benefit from ATR inhibition.

CONCLUSIONS

Our work highlights that combined monoallelic del(11q) and TP53 alterations coordinately contribute to clonal advantage and shorter overall survival in CLL.

Flow Cytometric Analysis of ZAP-70 Protein Expression for B-Cell Chronic Lymphocytic Leukemia Prognostication: Usefulness and Limitations

Objectives: The heterogenous clinical course in B-cell chronic lymphocytic leukemia (B-CLL) can be linked to several genetic and phenotypic characteristics of malignant B-cells. Prognostic analysis in B-CLL is routinely carried out to assist patient management; particularly to predict the time to initiate treatment. Increased ZAP-70 expression is a surrogate marker for unmutated immunoglobulin genes and inferior clinical outcomes which can be quantified to predict future outcomes in B-CLL patients. The study determined the ZAP-70 expression pattern using Z-index in Pakistani patients with B-CLL.

Methods: A retrospective analysis of B-CLL cases diagnosed and confirmed on flow cytometry at Aga Khan University Hospital for the last six years which had also undergone ZAP-70 analysis were included. In all these cases, ZAP-70 expression was quantified by measuring mean fluorescence intensities (MFIs) of normal B-cells, T-cells, and CLL-cells (CD19 and CD5 double-positive population). ZAP-70 expression was divided into high, low, and negative categories based on Z-index calculation. Mann-Whitney U test was utilized to determine the significance of ZAP-70 variations in different age groups and genders. P-value <0.05 was considered significant.

Results: A total of 120 patients of B-CLL had ZAP-70 analysis during the study period. The median age was 62 with an interquartile range of 35-87 and male to female ratio of 2:1. ZAP-70 expression was high in 18 (15%), low in 52 (43.3%) and negative in 50 (41.7%) cases. No significant difference in ZAP-70 expression with respect to the age or gender of the study population was identified using appropriate statistical calculations.

Conclusions: This study showed only 15% of B-CLL cases showing high ZAP-70 expression, a surrogate biomarker for possible aggressive behavior which may necessitate therapeutic intervention and close surveillance.

From Anti-EBV Immune Responses to the EBV Diseasome via Cross-reactivity

Sequence analyses highlight a massive peptide sharing between immunoreactive Epstein-Barr virus (EBV) epitopes and human proteins that—when mutated, deficient or improperly functioning—associate with tumorigenesis, diabetes, lupus, multiple sclerosis, rheumatoid arthritis, and immunodeficiencies, among others. Peptide commonality appears to be the molecular platform capable of linking EBV infection to the vast EBV-associated diseasome via cross-reactivity and questions the hypothesis of the “negative selection” of self-reactive lymphocytes. Of utmost importance, this study warns that using entire antigens in anti-EBV immunotherapies can associate with autoimmune manifestations and further supports the concept of peptide uniqueness for designing safe and effective anti-EBV immunotherapies.

Chronic Myelogenous Leukemia Diagnosed in the Setting of Untreated Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma

Chronic myeloid leukemia (CML) is rarely reported to occur in treated chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). In this article, we report a woman in her 70s, diagnosed with CLL/SLL in 2000, untreated, who subsequently presented 12 years later with de novo CML, BCR-ABL1+. Her IGHV mutated CLL/SLL based on the initial sample in our laboratory showed homozygous and heterozygous 13q14.3 deletions, whereas her CML, at presentation, showed a 46,XX,t(9;22)(q34;q11.2)[7]/46,XX[18] karyotype with a p190 BCR-ABL1 transcript. The tumor burden of each clone varied with treatment, including when treated with dasatinib, used to target both clones. In addition, the cytogenetic abnormalities evolved over time and treatments and included acquisition of an extra chromosome 8 in the CML clone and a novel K1992T ATM missense mutation (47% allele frequency) in the CLL/SLL clone. The patient's last bone marrow biopsy, 5 years after her CML diagnosis and 17 years after the CLL/SLL diagnosis, showed residual CML with extensive involvement by CLL/SLL (80%). Cytogenetic studies showed a 46,XX karyotype, while FISH identified 13q14.3 deletion and the BCR-ABL1 translocation in the CLL/SLL and CML clones, respectively. To date, this is the fourth case of concurrent CML, BCR-ABL1+ arising in untreated CLL/SLL. Here we show dynamic variation in the size of the 2 clonal processes reflecting the variable responsiveness to specific therapies. In addition to the unusual BCR-ABL1+ p190 transcript in the patient's CML, a novel ATM K1992T mutation was identified in the CLL/SLL population.

Drug-free macromolecular therapeutics induce apoptosis in cells isolated from patients with B cell malignancies with enhanced apoptosis induction by pretreatment with gemcitabine

Drug-free macromolecular therapeutics (DFMT) is a new paradigm for the treatment of B cell malignancies. Apoptosis is initiated by the biorecognition of complementary oligonucleotide motifs at the cell surface resulting in crosslinking of CD20 receptors. DMFT is composed from two nanoconjugates: 1) bispecific engager, Fab'-MORF1 (anti-CD20 Fab' fragment conjugated with morpholino oligonucleotide), and 2) a crosslinking (effector) component P-(MORF2)_X (N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer grafted with multiple copies of complementary morpholino oligonucleotide). We evaluated this concept in 44 samples isolated from patients diagnosed with various subtypes of B cell malignancies. Apoptosis was observed in 65.9% of the samples tested. Pretreatment of cells with gemcitabine (GEM) or polymer-gemcitabine conjugate (2P-GEM) enhanced CD20 expression levels thus increasing apoptosis induced by DFMT. These positive results demonstrated that DFMT has remarkable therapeutic potential in various subtypes of B cell malignancies.

Ig-Like Transcript 2 (ILT2) Blockade and Lenalidomide Restore NK Cell Function in Chronic Lymphocytic Leukemia

One of the cardinal features of chronic lymphocytic leukemia (CLL) is its association with a profound immunosuppression. NK cell function is markedly impaired in CLL patients, who show a significant dysregulation of the expression of activating and inhibitory receptors. Here, we analyzed the role of the novel inhibitory receptor Ig-like transcript 2 (ILT2, also termed LIR-1, LILRB1) in the regulation of NK cells in CLL. Our results show that ILT2 expression was significantly decreased on leukemic cells and increased on NK cells of CLL patients, particularly in those with advanced disease and with bad prognostic features, such as those carrying chromosome del(11q). The immunomodulatory drug lenalidomide may regulate the expression of ILT2 and its ligands in CLL since it significantly increased the expression of ILT2 and partially reestablished the expression of its ligands on leukemic cells. Furthermore, lenalidomide significantly increased the activation and proliferation of NK cells, which was strongly enhanced by ILT2 blockade. Combining ILT2 blockade and lenalidomide activated NK cell cytotoxicity resulting in increased elimination of leukemic cells from CLL patients. Overall, we describe herein the role of an inhibitory receptor involved in the suppression of NK cell activity in CLL, which is restored by ILT2 blockade in combination with lenalidomide, suggesting that it may be an interesting therapeutic strategy to be explored in this disease.

BCL6B suppresses proliferation and migration of colorectal carcinoma cells through inhibition of the PI3K/AKT signaling pathway

B‑cell CLL/lymphoma 6 member B (BCL6B), a BCL6‑homologous gene, has been reported to be a tumor suppressor that is silenced in a variety of human cancers, including colorectal cancer (CRC). Although it was recently demonstrated that reduced expression of BCL6B is associated with tumor stage and lymph node metastasis in CRC, little is known on whether BCL6B contributes to CRC development, or the related underlying mechanism. The aim of the present study was to detect BCL6B expression in CRC cells, and determine the molecular mechanisms underlying the role of BCL6B in CRC development by investigating cell proliferation and migration in vitro. As a result, BCL6B expression was found to be notably repressed in CRC cells compared with normal intestinal epithelial cells by reverse transcription‑polymerase chain reaction and western blot analysis. CRC cell proliferation was significantly inhibited by BCL6B upregulation, as indicated by MTT and colony‑forming assays. Cell apoptosis was markedly induced, as indicated by flow cytometry, and BCL6B‑transfected CRC cells exhibited decreased migration ability. Additionally, BCL6B overexpression diminished the phosphorylation level of AKT in CRC cells. These effects of BCL6B were empowered by treatment with the specific phosphoinositide 3 kinase (PI3K)/AKT inhibitor LY294002. Furthermore, overexpression of BCL6B resulted in upregulation of E‑cadherin and downregulation of cyclin D1 and matrix metalloproteinase‑9, which were strongly enhanced by LY294002. In conclusion, the findings of the present study demonstrated that BCL6B suppressed the proliferation and migration of CRC cells indirectly, via inhibition of PI3K.

Characterizing patients with multiple chromosomal aberrations detected by FISH in chronic lymphocytic leukemia

We analyzed the features of chronic lymphocytic leukemia (CLL) with multiple abnormalities (MA) detected by FISH. A local database including 2095 CLL cases was used and 323 with MA (15.4%) were selected. MA was defined by the presence of two or more alterations (deletions of 13q14 (13q-), 11q22 (11q-), 17p13 (17p-) or trisomy 12 (+12)). The combination of 13q- with 11q- and 13q- with 17p-, accounted for 58.2% of the series, in contrast to 11q- with 17p- (3.7%). Patients carrying MA since diagnosis presented a short time to first therapy(TTFT) (27 months) and overall survival (OS) (76 months). The combinations including 17p- had a shorter OS (58 months) than the ones without 17p- (not reached, p = .002). Patients with a complex-FISH were the ones with worse OS (34 months). MA imply poor prognosis when they emerge at diagnosis, probably due to the high incidence of bad prognosis markers, which may be a reflection of a more complex karyotype.

Ig-like transcript 2 (ILT2) suppresses T cell function in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is associated with a profound dysregulation of the immune system. Loss of T cell function is frequently caused in cancer by sustained signaling of inhibitory receptors. Here, we analyzed the role of the novel inhibitory receptor Ig-like transcript 2 (ILT2) in the pathogenesis of CLL. We observed that ILT2 expression was markedly reduced on leukemic cells, whereas it was increased on CD8 and CD4 T cells from CLL patients, particularly in those patients harboring chromosome 11q deletion, which includes the ATM gene. A deep dysregulation of ILT2 ligands expression in leukemia cells was also observed. ILT2 impaired the activation and proliferation of CD4 and CD8 T cells in CLL patients, but it had no effect in leukemic cells. ILT2 downregulated the production of IL-2 by CD4 T cells of CLL patients and induced the expression of cytokines that promote the survival of leukemic cells, such as IFN-γ, by T cells. Importantly, ILT2 blockade restored the activation, proliferation and cytokine production of T cells. In conclusion, we describe a novel immune inhibitory pathway that is upregulated in CLL and delineate a new potential target to be explored in this disease.

Chronic Lymphocytic Leukemia Patients With Deletion 11q Have a Short Time to Requirement of First-Line Therapy, But Long Overall Survival: Results of a Population-Based Cohort in British Columbia, Canada

BACKGROUND

Chronic lymphocytic leukemia (CLL) patients with 11q22.3 deletion (11q-) have an aggressive clinical course, and thus selection of first-line therapy in this group is important. This study aimed to improve our understanding of real-world practice patterns and outcomes of CLL patients with 11q- in a population-based setting.

PATIENTS AND METHODS

The British Columbia CLL Database was used to identify patients with 11q-. Overall survival (OS) and treatment-free survival (TFS) were assessed after adjustment for prognostic factors.

RESULTS

Of 1044 patients in the database, 125 had 11q- (12%). Sixty-nine patients had 11q- identified before therapy initiation and had a median OS and TFS of 14.7 (95% confidence interval [CI], 11.3-18.1) and 2.5 (95% CI, 1.5-3.6) years. Patient with copresence of 11q- and deletion 17p had a markedly worse prognosis, with median OS of 4.9 versus 14.7 years (P < .001). Most treated patients (33 of 52) received fludarabine with or without rituximab (FR). Patients treated with FR had a median OS of 12.8 years (standard error, 1.0), which was not statistically different from those treated with alkylator-containing therapy (P = .35).

CONCLUSION

Although median TFS of 11q- patients in this cohort was short at 2.5 years, OS remains long at 14.7 years, even when most patients received initial treatment without alkylators.

Spotlight on ibrutinib and its potential in frontline treatment of chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is the most prevalent leukemia in the adult population. Current efforts are focused on better understanding the intricate pathophysiology of the disease to develop successful targeted therapies. Ibrutinib is emerging as an important agent in this new age of targeted treatment for CLL. As a Bruton’s tyrosine kinase inhibitor, it blocks the signaling pathway that malignant B-lymphocytes need for growth and maturation. Ibrutinib’s role in therapy was further expanded recently when the US Food and Drug Administration approved its use in both frontline and salvage treatment for patients with CLL. This review assesses the effectiveness of ibrutinib in the frontline setting, its efficacy in various types of patients with CLL, and its safety and tolerability.

FISHing in the dark: How the combination of FISH and conventional karyotyping improves the diagnostic yield in CpG-stimulated chronic lymphocytic leukemia

Despite significant advances in molecular genetic approaches, fluorescence in situ hybridization (FISH) remains the gold standard for the diagnostic evaluation of genomic aberrations in patients with chronic lymphocytic leukemia (CLL). Efforts to improve the diagnostic utility of molecular cytogenetic testing have led to the expansion of the traditional 4-probe CLL FISH panel. Not only do these efforts increase the cost of testing, they remain hindered by the inherent limitations of FISH studies - namely the inability to evaluate genomic changes outside of the targeted loci. While array-based profiling and next generation sequencing (NGS) have critically expanded our understanding of the molecular pathogenesis of CLL, these methodologies are not routinely used by diagnostic laboratories to evaluate copy number changes or the mutational profile of this disease. Mitogenic stimulation of CLL specimens with CpG-oligonucleotide (CpG-ODN) has been identified as a reliable and reproducible means of obtaining a karyotype, facilitating a low-resolution genome-wide analysis. Across a cohort of 1255 CpG-ODN-stimulated CLL specimens, we describe the clinical utility associated with the combinatorial use of FISH and karyotyping. Our testing algorithm achieves a higher diagnostic yield (∼10%) through the detection of complex karyotypes, well-characterized chromosomal aberrations not covered by the traditional CLL FISH panel and through the detection of concurrent secondary malignancies. Moreover, the single cell nature of this approach permits the evaluation of emerging new clinical concepts including clonal dynamics and clonal evolution. This approach can be broadly applied by diagnostic laboratories to improve the utility of traditional and molecular cytogenetic studies of CLL. Am. J. Hematol. 91:978-983, 2016. © 2016 Wiley Periodicals, Inc.

Intratumoral genetic heterogeneity and number of cytogenetic aberrations provide additional prognostic significance in chronic lymphocytic leukemia

PURPOSE

Chronic lymphocytic leukemia (CLL) is a heterogeneous disease with cytogenetic aberrations that are still considered the gold standard of prognostic factors. However, heterogeneity remains within each cytogenetic group, especially in patients with concomitant cytogenetic aberrations.

METHODS

A panel of DNA probes was used to detect cytogenetic aberrations, including RB1/D13S25 at 13q14, ATM at 11q22, TP53 at 17p13, CEP12 and IGH translocation at 14q32, by fluorescence in situ hybridization. A comprehensive method integrating the number of cytogenetic aberrations and intratumoral genetic heterogeneity was used to analyze the prognosis for patients with concomitant aberrations.

RESULTS

Within the conventional favorable or neutral prognostic groups (i.e., with del 13q, trisomy 12, and/or t(14q32)), the coincidence of these three aberrations worsened survival in terms of time to first therapy, progression-free survival, and overall survival. However, within the conventional unfavorable prognostic group (i.e., del 11q or del 17p), patients with a minor unfavorable clone had an unexpected survival advantage compared with patients with a major unfavorable clone. A new cytogenetic prognostic system that integrates the number of cytogenetic aberrations and intratumoral genetic subclones was more precise than the conventional system.

CONCLUSION

The number of cytogenetic aberrations and the size of intratumoral genetic subclones should be comprehensively considered to determine the prognosis for CLL.Genet Med 19 2, 182-191.

BIRC3 alterations in chronic and B-cell acute lymphocytic leukemia patients

Deletions within chromosome 11q22-23, are considered among the most common chromosomal aberrations in chronic lymphocytic leukemia (CLL), and are associated with a poor outcome. In addition to the ataxia telangiectasia mutated (ATM) gene, the baculoviral IAP repeat-containing 3 (BIRC3) gene is also located in the region. BIRC3 encodes a negative regulator of the non-canonical nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) protein. Disruption of BIRC3 is known to be restricted to CLL fludarabine-refractory patients. The aim of the present study was to determine the frequency of copy number changes of BIRC3 and to assess its association with two known predictors of negative CLL outcome, ATM and tumor protein 53 (TP53) gene deletions. To evaluate the specificity of BIRC3 alterations to CLL, BIRC3 copy numbers were assessed in 117 CLL patients in addition to 45 B-cell acute lymphocytic leukemia (B-ALL) patients. A commercially available multiplex ligation dependent probe amplification kit, which includes four probes for the detection of TP53 and four probes for ATM gene region, was applied. Interphase-directed fluorescence in situ hybridization was used to apply commercially available probes for BIRC3, ATM and TP53. High resolution array-comparative genomic hybridization was conducted in selected cases. Genetic abnormalities of BIRC3 were detected in 23/117 (~20%) of CLL and 2/45 (~4%) of B-ALL cases. Overall, 20 patients with CLL and 1 with B-ALL possessed a BIRC3 deletion, whilst 3 patients with CLL and 1 with B-ALL harbored a BIRC3 duplication. All patients with an ATM deletion also carried a BIRC3 deletion. Only 2 CLL cases possessed deletions in BIRC3, ATM and TP53 simultaneously. Evidently, the deletion or duplication of BIRC3 may be observed rarely in B-ALL patients. BIRC3 duplication may occur in CLL patients, for which the prognosis requires additional studies in the future. The likelihood that TP53 deletions occur simultaneously with BIRC3 and/or ATM aberrations is low. However, as ATM deletions may, but not always, associate with BIRC3 deletions, each region should be considered in the future diagnostics of CLL in order to aid treatment decisions, notably whether to treat with or without fludarabine.

Frequencies of SF3B1, NOTCH1, MYD88, BIRC3 and IGHV mutations and TP53 disruptions in Chinese with chronic lymphocytic leukemia: disparities with Europeans

We studied 307 consecutive Chinese with chronic lymphocytic leukemia (CLL) in diverse disease-stages before and after diverse therapies for mutations in several CLL-related genes. Mutation frequencies were SF3B1, 5%, NOTCH1, 8%, MYD88, 8%, BIRC3, 2%, TP53, 15% and IGHV, 60%. Several of these frequencies differ from those reported in persons of predominately European descent with CLL. Biological and clinical associations were detected including SF3B1 and NOTCH1 mutations with un-mutated IGHV, MYD88 mutations with mutated IGHV, SF3B1 mutations with fludarabine-resistant CLL and NOTCH1 mutation with advanced Binet disease stage and with +12. The NOTCH1 correlation with briefer survival was confirmed in multivariate analyses but the SF3B1 correlation was confounded by concurrent mutations in TP53 and germline IGHV. We show differences in incidence and prognostic impact of mutations in Chinese and CLL compared with persons of predominately European descent with CLL. These data may give insights into the etiology and biology of CLL and suggests different risk stratification models may be needed for different CLL populations.

Acute Megakaryoblastic Leukemia with Myelodysplasia-related Changes Associated with ATM Gene Deletion

Ataxia telangiectasia mutated (ATM) is a tumor suppressor gene, and its somatic inactivation plays a role in the pathogenesis of lymphoid malignancies. However, the role of ATM in patients with myeloid malignancies is still unknown. We herein report a case of acute megakaryoblastic leukemia (AMKL) with ATM gene deletion. An 84-year-old Japanese woman presenting with a pale face and pancytopenia was admitted to our institution and diagnosed to have AMKL with ATM gene deletion. She was treated with intravenous azacitidine. The azacitidine treatment was effective for approximately 1 year. Somatic inactivation of the ATM gene may therefore be involved in the pathogenesis of AMKL.

A Low Frequency of Losses in 11q Chromosome Is Associated with Better Outcome and Lower Rate of Genomic Mutations in Patients with Chronic Lymphocytic Leukemia

To analyze the impact of the 11q deleted (11q-) cells in CLL patients on the time to first therapy (TFT) and overall survival (OS), 2,493 patients with CLL were studied. 242 patients (9.7%) had 11q-. Fluorescence in situ hybridization (FISH) studies showed a threshold of 40% of deleted cells to be optimal for showing that clinical differences in terms of TFT and OS within 11q- CLLs. In patients with ≥40% of losses in 11q (11q-H) (74%), the median TFT was 19 months compared with 44 months in CLL patients with <40% del(11q) (11q-L) (P<0.0001). In the multivariate analysis, only the presence of 11q-L, mutated IGHV status, early Binet stage and absence of extended lymphadenopathy were associated with longer TFT. Patients with 11q-H had an OS of 90 months, while in the 11q-L group the OS was not reached (P = 0.008). The absence of splenomegaly (P = 0.02), low LDH (P = 0.018) or β2M (P = 0.006), and the presence of 11q-L (P = 0.003) were associated with a longer OS. In addition, to detect the presence of mutations in the ATM, TP53, NOTCH1, SF3B1, MYD88, FBXW7, XPO1 and BIRC3 genes, a select cohort of CLL patients with losses in 11q was sequenced by next-generation sequencing of amplicons. Eighty % of CLLs with 11q- showed mutations and fewer patients with low frequencies of 11q- had mutations among genes examined (50% vs 94.1%, P = 0.023). In summary, CLL patients with <40% of 11q- had a long TFT and OS that could be associated with the presence of fewer mutated genes.

High fluorescence in situ hybridization percentage of deletion 11q in patients with chronic lymphocytic leukemia is an independent predictor of adverse outcome

We have analyzed patients with previously untreated chronic lymphocytic leukemia with del11q fluorescence in situ hybridization (FISH) abnormality (n = 196) in this study. Detection of the 11q22.3 used a multicolor FISH technique. Patients with del11q fell into two major FISH subsets-sole del11q (n = 64) and del11q with del13q (n = 132). FISH subsets were compared using the median del11q FISH% (>58%, high vs. ≤58%, low). Overall survival (OS) and time to first treatment (TTFT) were estimated using Kaplan-Meier plots (log rank). Multivariate analysis was performed to assess the association between FISH% of del11q and outcomes. Patients with sole del11q were similar to del11q with del13q in terms of TTFT and OS. Patients with high FISH% of del11q had significantly shorter OS and TTFT as compared with patients with low FISH%, particularly in sole del11q; this negative impact of high FISH% of del11q on OS and TTFT was diminished with coexistent del13q. In multivariate analysis, high FISH% of del11q was a significant predictor for shorter OS and TTFT. A comparison of these del11q subsets with a separate cohort of (n = 673) previously untreated patients with sole del13q showed that the high FISH% del11q cohort had a significantly shorter TTFT and OS. In addition, bulky disease by physical examination or computed tomography imaging was infrequent at presentation in patients with del11q. High FISH% of del11q can reliably discriminate higher risk patients with chronic lymphocytic leukemia. Presence of coexistent del13q should be accounted for while prognosticating patients with del11q.

A phase 2 study of the BH3 mimetic BCL2 inhibitor navitoclax (ABT-263) with or without rituximab, in previously untreated B-cell chronic lymphocytic leukemia

We evaluated the safety and biologic activity of the BH3 mimetic protein, navitoclax, combined with rituximab, in comparison to rituximab alone. One hundred and eighteen patients with chronic lymphocytic leukemia (CLL) were randomized to receive eight weekly doses of rituximab (arm A), eight weekly doses of rituximab plus daily navitoclax for 12 weeks (arm B) or eight weekly doses of rituximab plus daily navitoclax until disease progression or unacceptable toxicity (arm C). Investigator-assessed overall response rates (complete [CR] and partial [PR]) were 35% (arm A), 55% (arm B, p = 0.19 vs. A) and 70% (arm C, p = 0.0034 vs. A). Patients with del(17p) or high levels of BCL2 had significantly better clinical responses when treated with navitoclax. Navitoclax in combination with rituximab was well tolerated as initial therapy for patients with CLL, yielded higher response rates than rituximab alone and resulted in prolonged progression-free survival with treatment beyond 12 weeks.

Mutations in chronic lymphocytic leukemia and how they affect therapy choice: focus on NOTCH1, SF3B1, and TP53

Chronic lymphocytic leukemia (CLL) is characterized by a relatively small number of recurrent genetic defects. These can be evaluated by clinically available methods such as fluorescent in situ hybridization and targeted sequencing approaches to provide data that can be very helpful in prognostication and planning of treatment. Acquired defects in the p53 pathway, activating mutations of NOTCH1, and dysfunctional mutations of SF3B1 and BIRC3 identify patients with higher risk of progressive disease, poorer responses to conventional chemoimmunotherapy, and shorter survival. Risk stratification using these data can identify patients with aggressive CLL who require careful monitoring and are unlikely to have durable responses to chemoimmunotherapy at disease progression. Patients with defective DNA damage repair mechanisms because of p53 dysfunction should be considered for non-chemotherapy-based regimens including tyrosine kinase inhibitors, BCL2 inhibitors, monoclonal antibodies, and immunological therapies including allogeneic transplantation and chimeric antigen receptor-targeted T cells. Conversely, patients with no high-risk mutations can usually be monitored for a prolonged time and are likely to have durable responses to chemoimmunotherapy at disease progression. New technologies for genetic analysis such as targeted next-generation sequencing have the potential to make these analyses cheaper, faster, and more widely available. Comprehensive genetic analysis of patients both at diagnosis and before treatment for progressive disease could become an integral component of care for CLL.

Comprehensive chronic lymphocytic leukemia diagnostics by combined multiplex ligation dependent probe amplification (MLPA) and interphase fluorescence in situ hybridization (iFISH)

Background

Banding-karyotyping and metaphase-directed-fluorescence-in-situhybridization (FISH) may be hampered by low mitotic index in leukemia. Interphase FISH (iFISH) is a way out here, however, testing many probes at the same time is protracted and expensive. Here multiplex-ligation-dependent-probe-amplification (MLPA) was used retrospectively in chronic lymphocytic leukemia (CLL) samples initially studied by banding cytogenetics and iFISH. Detection rates of iFISH and MLPA were compared and thus a cost-efficient scheme for routine diagnostics is proposed.

Results

Banding cytogenetics was done successfully in 67/85 samples. DNA was extracted from all 85 CLL samples. A commercially available MLPA probe set directed against 37 loci prone to be affected in hematological malignancies was applied. Besides, routine iFISH was done by commercially available probes for following regions: 11q22.3, 12p11.2-q11.1, 13q14.3, 13q34, 14q32.33 and 17p13.1. MLPA results were substantiated by iFISH using corresponding locus-specific probes.

Aberrations were detected in 67 of 85 samples (~79%) applying banding cytogenetics, iFISH and MLPA. A maximum of 8 aberrations was detected per sample; however, one aberration per sample was found most frequently. Overall 163 aberrations were identified. 15 of those (~9%) were exclusively detected by banding cytogenetics, 95 were found by MLPA (~58%) and 100 (~61%) by routine iFISH. MLPA was not able to distinguish reliably between mono- and biallelic del(13)(q14.3q14.3), which could be easily identified as well as quantified by routine iFISH. Also iFISH was superior to MLPA in samples with low tumor cell load. On the other hand MLPA detected additional aberrations in 22 samples, two of them being without any findings after routine iFISH.

Conclusions

Both MLPA and routine iFISH have comparable detection rates for aberrations being typically present in CLL. As MLPA can detect also rare chromosomal aberrations it should be used as an initial test if routine cytogenetics is not possible or non-informative. Still iFISH should be used additionally to distinguish mono- from biallelic deletions and also to determine rate of mosaicism for 13q14.2 to 13q14.3. In case MLPA is negative the corresponding CLL samples should be tested at least by iFISH using the standard probe set to.

Electronic supplementary material

The online version of this article (doi:10.1186/s13039-014-0079-2) contains supplementary material, which is available to authorized users.

Chemoimmunotherapy for relapsed/refractory and progressive 17p13-deleted chronic lymphocytic leukemia (CLL) combining pentostatin, alemtuzumab, and low-dose rituximab is effective and tolerable and limits loss of CD20 expression by circulating CLL cells

Chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL) patients with purine analog refractory disease or TP53 dysfunction still have limited treatment options and poor survival. Alemtuzumab-containing chemoimmunotherapy regimens can be effective but frequently cause serious infections. We report a Phase II trial testing the efficacy and tolerability of a short-duration regimen combining pentostatin, alemtuzumab, and low-dose high-frequency rituximab designed to decrease the risk of treatment-associated infections and to limit the loss of CD20 expression by CLL cells. The study enrolled 39 patients with progressive CLL that was either relapsed/refractory (n = 36) or previously untreated with 17p13 deletion (17p13-) (n = 3). Thirteen (33%) patients had both 17p13- and TP53 mutations predicted to be dysfunctional, and eight patients had purine analog refractory CLL without TP53 dysfunction. Twenty-six (67%) patients completed therapy, with only five (13%) patients having treatment-limiting toxicity and no treatment-related deaths. Twenty-two (56%) patients responded to treatment, with 11 (28%) complete responses (four with incomplete bone marrow recovery). Median progression-free survival was 7.2 months, time to next treatment was 9.1 months, and overall survival was 34.1 months. The majority of deaths (82%) were caused by progressive disease, including transformed diffuse large B-cell lymphoma (n = 6). Correlative studies showed that low-dose rituximab activates complement and natural killer cells without a profound and sustained decrease in expression of CD20 by circulating CLL cells. We conclude that pentostatin, alemtuzumab, and low-dose high-frequency rituximab is a tolerable and effective therapy for CLL and that low-dose rituximab therapy can activate innate immune cytotoxic mechanisms without substantially decreasing CD20 expression.

Effect of transfection with bcl6b on biological behavior of human esophageal cancer cells

AIM: To determine the effect of exogenous bcl6b gene on biological behavior of human esophageal cancer cells.

METHODS: PCR was used to clone the bcl6b gene to construct the pcDNA-bcl6b vector. The pcDNA-bcl6b and pcDNA3.1 (empty vector) were introduced into KYSE180 cell line using Lipofectin, and the KYSE180 cells stably expressing the bcl6b gene were established by G418 selection. The expression of BCL6B, P53 and P21 proteins was detected by Western blot. Cell cycle and apoptosis were assayed by flow cytometry (FCM). Cell proliferation was observed by growth curve and colony formation assays.

RESULTS: KYSE180 cells stably expressing BCL6B protein were established. FCM showed that more BCL6B-transfected cells entered into G₀/G₁ phase (BCL6B: 47.85% ± 1.53% vs empty vector: 40.62% ± 1.07%, P < 0.05) and fewer cells entered into S phase (BCL6B: 34.40% ± 1.30% vs empty vector: 42.31% ± 0.66%, P < 0.01) compared with cells transfected with the empty vector. Moreover, there was a significant difference in the apoptosis rate between the two groups (BCL6B: 11.74% ± 0.99% vs empty vector: 2.43% ± 0.70%, P < 0.01), and P53 and P21 protein expression levels were significantly increased. Compared with the empty vector transfected cells, the BCL6B-transfected cells grew more slowly.

CONCLUSION: BCL6B protein might inhibit the malignant biological behavior of KYSE180 cells partly by up-regulating P53 and P21 protein expression.