Biomarkers in chronic lymphocytic leukemia: Clinical applications and prognostic markers

B Cell Subsets and Immune Checkpoint Expression in Patients with Chronic Lymphocytic Leukemia

Chronic lymphocytic leukemia (CLL) is characterized by dysfunctional B cells. Immune checkpoint molecules such as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed death-1 (PD-1) are upregulated in patients with CLL and may correlate with prognostic markers such as beta-2 microglobulin (B2M). The aim of this study was to evaluate the levels of immune checkpoints on B cell subsets and to further correlate them with B2M levels in patients with CLL. We recruited 21 patients with CLL and 12 controls. B cell subsets and the levels of immune checkpoint expression were determined using conventional multi-color flow cytometry. Basal levels of B2M in patients with CLL were measured using an enzyme-linked immunosorbent assay. Patients with CLL had increased levels of activated B cells when compared to the control group, p < 0.001. The expression of PD-1 and CTLA-4 were increased on activated B cells and memory B cells, p < 0.05. There were no associations between B2M levels and the measured immune checkpoints on B cell subsets, after adjusting for sex and age. In our cohort, the patients with CLL expressed elevated levels of PD-1 and CTLA-4 immune checkpoints on activated and memory B cell subsets. However, there was no correlation between these immune checkpoint expressions and B2M levels.

Can Galectin-3 Be a Novel Biomarker in Chronic Lymphocytic Leukemia?

Galectin-3's (Gal-3) effect on the pathogenesis of chronic lymphocytic leukemia (CLL) has not yet been extensively studied. The present study aims to analyze the potential role of Gal-3 as a prognostic biomarker in CLL patients. The Gal-3 expression was evaluated in CLL cells with RT-qPCR and flow cytometry. Due to the unclear clinical significance of soluble Gal-3 in CLL, our goal was also to assess the prognostic value of Gal-3 plasma level. Because cell survival is significantly affected by the interaction between Gal-3 and proteins such as Bcl-2, the results of Gal-3 expression analysis were also compared with the expression of Bcl-2. The results were analyzed for known prognostic factors, clinical data, and endpoints such as time to first treatment and overall survival time. Our research confirmed that Gal-3 is detected in and on CLL cells. However, using Gal-3 as a potential biomarker in CLL is challenging due to the significant heterogeneity in its expression in CLL cells. Moreover, our results revealed that Gal-3 mRNA expression in leukemic B cells is associated with the expression of proliferation markers (Ki-67 and PCNA) as well as anti-apoptotic protein Bcl-2 and can play an important role in supporting CLL cells.

Prognostic Potential of Galectin-9 mRNA Expression in Chronic Lymphocytic Leukemia

Galectin-9 (Gal-9), very poorly characterized in chronic lymphocytic leukemia (CLL), was chosen in our study to examine its potential role as a CLL biomarker. The relation of Gal-9 expression in malignant B-cells and other routinely measured CLL markers, as well as its clinical relevance are poorly understood. Gal-9 mRNA expression was quantified with RT-qPCR in purified CD19+ B-cells of 100 CLL patients and analyzed in the context of existing clinical data. Our results revealed the upregulation of Gal-9 mRNA in CLL cells. High Gal-9 mRNA expression was closely associated with unfavorable prognostic markers. In addition, Gal-9 expression in leukemic cells was significantly elevated in CLL patients who did not respond to the first-line therapy compared to those who did respond. This suggests its potential predictive value. Importantly, Gal-9 was an independent predictor for the time to treatment parameters. Thus, we can suggest an adverse role of Gal-9 expression in CLL. Interestingly, it is possible that Gal-9 expression is induced in B-cells by EBV infection, so we determined the patients' EBV status. Our suggestion is that EBV coinfection could worsen prognosis in CLL, partly due to Gal-9 expression upregulation caused by EBV.

Patterns of use of biological and genetic markers for chronic lymphocytic leukemia and acute myeloid leukemia in Puerto Rico

BACKGROUND

The use of markers has stimulated the development of more appropriate targeted therapies for chronic lymphocytic leukemia (CLL) and acute myeloid leukemia (AML). We assessed the use and prevalence of biological and genetic markers of CLL and AML in the homogeneous Hispanic population of Puerto Rico.

METHODS

We used the Puerto Rico CLL/AML Population-Based Registry, which combines information from linked databases. Logistic regression models were used to examine factors associated with biological and genetic testing.

RESULTS

A total of 926 patients 18 years or older diagnosed with CLL (n = 518) and AML (n = 408) during 2011-2015 were included in this analysis. Cytogenetic testing (FISH) was reported for 441 (85.1%) of the CLL patients; of those, 24.0% had the presence of trisomy 12, 9.5% carried deletion 11q, 50.3% carried deletion 13q, and 6.3% carried deletion 17p. Regarding AML, patients with cytogenetics and molecular tests were considered to determine the risk category (254 patients), of which 39.8% showed poor or adverse risk. Older age and having more comorbidities among patients with CLL were associated with a lower likelihood of receiving a FISH test.

CONCLUSIONS

Although prognostic genetic testing is required for treatment decisions, the amount of testing in this Hispanic cohort is far from ideal. Furthermore, some tests were not homogeneously distributed in the population, which requires further exploration and monitoring. This study contributes to the field by informing the medical community about the use and prevalence of biological and genetic markers of CLL and AML. Similarly, it has the potential to improve the management of CLL and AML through benchmarking.

High-resolution Melting Analysis for NOTCH1 c.7541-7542delCT Mutation in Chronic Lymphocytic Leukemia: Prognostic Significance in Egyptian Patients

The present study aimed to detect the prevalence of NOTCH1 c.7541-7542delCT mutation in Egyptian CLL patients using HRM assay and to assess its relation to patients' survival. The study included 50 newly diagnosed treatment-naïve CLL patients and 50 age and sex matched healthy controls. NOTCH1 c.7541-7542delCT mutation was detected using High-resolution melting (HRM) assay and direct Sanger sequencing. Outcome parameters included progression free survival (PFS) and overall survival (OS). NOTCH1 c.7541-7542delCT mutation was detected in 5 (10.0%) of CLL patients. No controls had NOTCH1 c.7541-7542delCT mutation. Similar results were obtained by direct Sanger sequencing yielding a sensitivity and specificity of 100.0% for HRM in detection of NOTCH1 c.7541-7542delCT mutation in the studied patients. In univariate analysis, predictors of OS included Trisomy 12, high LDH, presence of NOTCH1 c.7541-7542delCT mutation and lack of CR. In multivariate analysis, only lack of CR was found as a significant predictor of OS. HRM analysis is a sensitive method for detection of NOTCH1 c.7541-7542delCT mutation in CLL patients. This mutation may be linked to poor disease prognosis.

A Ferroptosis Molecular Subtype-Related Signature for Predicting Prognosis and Response to Chemotherapy in Patients with Chronic Lymphocytic Leukemia

Ferroptosis is a type of regulated cell death catalyzed by the iron-dependent accumulation of lipid hydroperoxides to lethal levels. Chronic lymphocytic leukemia (CLL) is a chronic lymphoproliferative disorder. However, the understanding of ferroptosis in CLL remains largely poor. In this study, we investigated the stratification and prognostic role of ferroptosis-related genes in CLL patients of ICGC cohort. We obtained fourteen genes with prognostic value by screening 110 ferroptosis-related genes (FRGs). Based on the expression profiles of these 14 genes, we classified CLL patients into two clusters. Most of the FRGs were highly expressed in cluster 1, and cluster 1 was associated with better overall survival (OS). Subsequently, we developed an eight-gene signature (TP63, STEAP3, NQO1, ELAVL1, PRKAA1, HELLS, FANCD2, and CDKN2A) by using LASSO analysis. This risk signature divided CLL patients into high- and low-risk groups. We used Cox regression analysis and ROC analysis demonstrated the risk signature was reliable and robust. And we validated the risk model in an external cohort (GSE22762). We also conducted enrichment analysis and genomic mutation analysis. Finally, we explored the potential effect of chemotherapy between the two risk groups. Our study contributed to understanding the role of ferroptosis in CLL and facilitated personalized and precision treatment.

p53 p.Pro72Arg (rs1042522) and Mouse Double Minute 2 (MDM2) Single-Nucleotide Polymorphism (SNP) 309 Variants and Their Interaction in Chronic Lymphocytic Leukemia(CLL): A Survey in CLL Patients from Western Iran

Background: Chronic lymphocytic leukemia (CLL) is the most common leukemia in adults. The MDM2 and p53 are interacting proteins that play crucial roles in cell biology. Genetic variations of p53 and MDM2 have been identified in many cancers including CLL; among which are SNP309 in the promoter of MDM2 and SNP codon72 in p53. Materials and Methods: In this study, we sought to find the impact of two SNPs of p53 and MDM2 in the pathogenesis of CLL. A total of 100 CLL patients and 102 healthy controls were recruited. Genomic DNA was extracted, and genotyping was performed using the PCR-RFLP method. The allele and genotype associations were analyzed using the χ2 test. The gene-gene interaction analysis was studied using GMDR v0.9. Results: Our study found the absence of a significant difference between CLL patients and controls related to the allelic frequencies or genotypic distributions for both MDM2 SNP309 and p53 codon72. A significantly higher frequency of p53 C allele was found in patients with disease duration of more than 36 compared to those less than 36 months. However, GMDR analysis suggests genetic interaction between the genes under study. Conclusion: Our findings indicated each polymorphism of p53 codon72 and MDM2 (SNP309) was not a risk factor for CLL but the p53 C allele could be associated with the disease duration. Besides, the interaction between p53/MDM2 genotypes may confer susceptibility to CLL. Our study could be useful in genetic association studies of CLL and the role of gene-gene interactions in the susceptibility to the disease.

O-GlcNAcylation in early stages of chronic lymphocytic leukemia; protocol development for flow cytometry

BACKGROUND

Recent studies proved that metabolic changes in malignant disorders have an impact on protein glycosylation, however, only a few attempts have been made so far to use O-GlcNAc analysis as a prognostic tool. Glucose metabolism is reported to be altered in hematological malignancies thus, we hypothesized that monitoring intracellular O-GlcNAc levels in Rai stage 0-I (Binet A) CLL patients could give deeper insights regarding subtle metabolic changes of progression which are not completely detected by the routine follow-up procedures.

OBJECTIVE

In this proof of concept study we established a flow cytometric detection method for the assessment of O-GlcNAcylation as a possible prognostic marker in CLL malignancy which was supported by fluorescence microscopy.

METHODS

Healthy volunteers and CLL patients were recruited for this study. Lymphocytes were isolated, fixed and permeabilised by various methods to find the optimal experimental condition for O-GlcNAc detection by flow cytometry. O-GlcNAc levels were measured and compared to lymphocyte count and various blood parameters including plasma glucose level.

RESULTS

The protocol we developed includes red blood cell lysis, formalin fixation, 0.1% Tween 20 permeabilisation and employs standardized cell number per sample and unstained controls. We have found significant correlation between O-GlcNAc levels and WBC (R2= 0.8535, p< 0.0029) and lymphocyte count (R2= 0.9225, p< 0.0006) in CLL patients. Interestingly, there was no such correlation in healthy individuals (R2= 0.05664 for O-GlcNAc vs WBC and R2= 0.04379 for O-GlcNAc vs lymphocytes).

CONCLUSION

Analyzing O-GlcNAc changes in malignant disorders, specifically in malignant hematologic diseases such as CLL, could be a useful tool to monitor the progression of the disease.

Relationship between Chromosomal Aberrations and Gene Expressions in the p53 Pathway in Chronic Lymphocytic Leukemia

Chronic lymphocytic leukemia (CLL) is a neoplasm characterized by excessive accumulation of B lymphocytes in the peripheral blood, bone marrow and lymph nodes. We assessed the expressions of 22 genes in the p53 pathway in 30 CLL patients and 15 healthy subjects by a RT2 Profiler PCR (polymerase chain reaction) Array technique and their relation to cytogenetic aberrations detected by fluorescent in situ hybridization (FISH). Our Student’s t-test results indicated that ATM, ATR, BAX, CASP9, CDK4, CDKN2A, CHEK1, CHEK2, E2F3, MCL1, MDM2, MDM4, PCNA, RB1, P53 and BCL2 genes were statistically significant (p <0.001). For six genes (APAF1, CDKN1A, E2F1, GADD45A, PTEN and PTX3) were not statistically significant. The ATM, ATR, BAX, CASP9, CDK4, CDKN1A, CDKN2A, CHEK1, CHEK2, MDM2, MDM4, PCNA, RB1, P53, E2F1, GADD45A and BCL2 genes were found to be upregulated by the 2^-ᐃᐃCt (relative fold change in gene expression) method. The highest up-regulation was detected in CDKN2A and BCL2 genes, 10.22- and 8.51-fold, respectively. On the other hand, the PTX3 gene with a fold regulation of 1.84 was found to the highest downregulation. Overall, the CDNK2A BCL2 and PTX3 genes are related to the mechanism of the disease in the p53 pathway and may be an important predictor of the prognosis of the disease. The BCL2 gene may be associated with increased risk of developing CLL. We suggest that the PTX3 gene may be considered as a marker associated with CLL disease. The CDKN2A gene expression seems to play a protective role in CLL.

Recent progress of prognostic biomarkers and risk scoring systems in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is the most prevalent adult leukemia with high heterogeneity in the western world. Thus, investigators identified a number of prognostic biomarkers and scoring systems to guide treatment decisions and validated them in the context of immunochemotherapy. A better understanding of prognostic biomarkers, including serum markers, flow cytometry outcomes, IGHV mutation status, microRNAs, chromosome aberrations and gene mutations, have contributed to prognosis in CLL. Del17p/ TP53 mutation, NOTCH1 mutation, CD49d, IGHV mutation status, complex karyotypes and microRNAs were reported to be of predictive values to guide clinical decisions. Based on the biomarkers above, classic prognostic models, such as the Rai and Binet staging systems, MDACC nomogram, GCLLSG model and CLL-IPI, were developed to improve risk stratification and tailor treatment intensity. Considering the presence of novel agents, many investigators validated the conventional prognostic biomarkers in the setting of novel agents and only TP53 mutation status/del 17p and CD49d expression were reported to be of prognostic value. Whether other prognostic indicators and models can be used in the context of novel agents, further studies are required.

The power of microRNAs as diagnostic and prognostic biomarkers in liquid biopsies

In the last decades, progresses in medical oncology have ameliorated the treatment of patients and their outcome. However, further improvements are still necessary, in particular for certain types of tumors such as pancreatic, gastric, and lung cancer as well as acute myeloid leukemia where early detection and monitoring of the disease are crucial for final patient outcome. Liquid biopsy represents a great advance in the field because it is less invasive, less time-consuming, and safer compared to classical biopsies and it can be useful to monitor the evolution of the disease as well as the response of patients to therapy. Liquid biopsy allows the detection of circulating tumor cells, nucleic acids, and exosomes not only in blood but also in different biological fluids: urine, saliva, pleural effusions, cerebrospinal fluid, and stool. Among the potential biomarkers detectable in liquid biopsies, microRNAs (miRNAs) are gaining more and more attention, since they are easily detectable, quite stable in biological fluids, and show high sensitivity. Many data demonstrate that miRNAs alone or in combination with other biomarkers could improve the diagnostic and prognostic power for many different tumors. Despite this, standardization of methods, sample preparation, and analysis remain challenging and a huge effort should be made to address these issues before miRNA biomarkers can enter the clinic. This review summarizes the main findings in the field of circulating miRNAs in both solid and hematological tumors.

Prognostic Testing and Treatment Patterns in Chronic Lymphocytic Leukemia in the Era of Novel Targeted Therapies: Results From the informCLL Registry

informCLL is the first United States-based registry of patients with chronic lymphocytic leukemia that initiated enrollment after approval of novel targeted agents. Prognostic/predictive testing rates and chronic lymphocytic leukemia treatment selection with availability of novel agents have not been previously investigated in clinical practice. Results from this interim analysis demonstrate that prognostic/predictive testing was infrequently used to guide treatment selection, potentially inhibiting beneficial outcomes for patients.

Increased serum levels of Galectin-9 in patients with chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in adults. Despite improvements in treatment, CLL is still considered an incurable disease. The aim of the present study was to evaluate galectin-1, -3 and -9 (Gal-1, -3 and -9) and Gal-3 binding protein (Gal-3BP) as prognostic and predictive factors in patients with CLL. Serum concentrations of Gal-1, -3 and -9 and Gal-3BP were measured in 48 patients with CLL and 30 control patients, using multiplex bead arrays. In patients with CLL, galectin concentrations were assessed prior to, during and following treatment. In patients with CLL who were untreated, galectin concentrations were measured twice with a 6-month interval. The serum level of Gal-9 was significantly increased (P<0.0001) in patients with CLL compared with the control group, and was associated with the clinical stage according to Binet classification, as well as poor cytogenetic and serum CLL prognostic factors. In addition, patients with CLL, who exhibited treatment failure, exhibited higher concentrations of Gal-9 (P=0.06) and Gal-3BP (P=0.009) at the end of the treatment when compared with patients under complete remission or stabilization of the disease. The serum level of Gal-3 was significantly decreased (P=0.012) in patients with CLL compared with the control group. These results suggest that Gal-9 is a potential prognostic factor in patients with CLL. The predictive value of Gal-9 requires further study in larger cohorts of patients.

Is there a role for the platelet-to-lymphocyte ratio in chronic lymphocytic leukemia?

AIM

The rationale for platelet-to-lymphocyte ratio (PLR) in chronic lymphocytic leukemia (CLL) is that both the platelet and lymphocyte counts are affected by the CLL pathogenesis and could influence treatment decision-making.

METHODS

Demographic and clinical data of CLL patients diagnosed at our institution between 1989 and 2013 were collected. Cox regression models were used to evaluate the role of PLR in the duration of watchful waiting, postdiagnosis survival and postchemotherapy survival.

RESULTS

The data of 100 patients with CLL were reviewed for this study. The PLR correlated only to watchful waiting in the univariable analysis (Hazard ratio = 0.48 [0.32-0.73]; p = 0.018). In the multivariable analysis, the duration of watchful waiting was determined by Binet staging and lymphocyte count (p < 0.001). The postdiagnosis survival was determined by age (p = 0.002) and lymphocyte count (p = 0.010).

CONCLUSION

The PLR did not seem to act as a prognostic biomarker for CLL.

On the architecture of translational research designed to control chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) has been 1 of the most dynamic fields of clinical research over the last 2 decades. Important advances in understanding the biology of CLL have led to the development of new prognostic and diagnostic tools. Concurrently, several recently approved new agents hold the potential to fundamentally change the management of this leukemia and have started to improve clinical outcomes for patients. This conceptual review summarizes the major recent insights regarding the biology of CLL, the technological advances that have allowed refinement of the prognostication of the clinical course, and the new therapeutic strategies that are currently under investigation to further ameliorate the outcome for patients with CLL.

Regulating glioma stem cells by hypoxia through the Notch1 and Oct3/4 signaling pathway

To investigate the effects of hypoxia on the features of cancer stem cells in the glioma cancer U87 cell line and underlying mechanism, stem cell markers and features in U87 were studied under the hypoxic and normoxic culture conditions by reverse transcription-quantitative polymerase chain reaction, western blot analysis, MTT, a colony formation test and flow cytometry. Compared to the normoxic group, the cluster of differentiation 133+ phenotype, clone formation rate and cell vitality were significantly elevated in U87 cells cultured in a hypoxic microenvironment. Also, the mRNA and protein expression of neurogenic locus notch homolog protein 1 (Notch1) and Oct3/4 were significantly elevated in U87 cells cultured in a hypoxic microenvironment, however, transcription factor SOX-2 expression was not significantly changed. These results indicate that hypoxia can promote the proliferation of glioma stem cells and maintain the characteristics of stem cells through the activation of Notch1 and Oct3/4 or Notch1 activation, affecting the biological characteristics of glioma cells.

Distinct Activities of Glycolytic Enzymes Identify Chronic Lymphocytic Leukemia Patients with a more Aggressive Course and Resistance to Chemo-Immunotherapy

A higher capacity to grow under hypoxic conditions can lead to a more aggressive behavior of tumor cells. Determining tumor activity under hypoxia may identify chronic lymphocytic leukemia (CLL) with aggressive clinical course and predict response to chemo-immunotherapy (CIT). A metabolic score was generated by determining pyruvate kinase and lactate dehydrogenase, key enzymes of glycolysis, ex vivo in primary CLL samples under normoxic and hypoxic conditions. This score was further correlated with clinical endpoints and response to CIT in 96 CLL patients. 45 patients were classified as metabolic high risk (HR), 51 as low risk (LR). Treatment-free survival (TFS) was significantly shorter in HR patients (median 394 vs 723 days, p = .021). 15 HR patients and 14 LR patients received CIT after sample acquisition. HR patients had a significantly shorter progression-free survival after treatment compared to LR patients (median 216 days vs not reached, p = .008). Multivariate analysis evaluating age, IGHV, TP53 deletion or mutation and 11q22–23 deletion besides the capacity of tumor cells to grow under severe hypoxic conditions identified the metabolic profile as the strongest independent risk factor for shorter TFS (hazard ratio 2.37, p = .011). The metabolic risk can provide prognostic and predictive information complementary to genetic biomarkers and identify patients who might benefit from alternative treatment approaches.

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The activity of distinct glycolytic enzymes can identify CLL patients with resistance to chemo-immunotherapy

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The activity of distinct glycolytic enzymes can identify CLL patients who may benefit from specific pathway inhibitors

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We provide a tool for the evaluation of specific glycolytic enzymes in primary CLL cells for clinical diagnostics

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

Objective: To summarize and investigate the characteristics, prognosis and treatments of chronic lymphocytic leukemia (CLL) patients with trisomy 12 by using FISH (CEP12). Methods: Clinical data of 330 CLL patients were analyzed retrospectively by using FISH (CEP12) to detect trisomy 12 from May 2003 to April 2015. The clinical data and laboratory characteristics of CEP12 positive patients (70 cases) were compared with those CEP12 negative patients (260 cases). Results: Compared with CEP12 negative CLL patients, the proportion of hepatomegaly (13.6% vs 4.0%, P=0.011) and LDH>247 U/L (43.3% vs 18.5%, χ(2)=15.892, P<0.001) in CEP12 positive CLL patients were much higher, respectively. There were no significant differences between age, sex, clinical stage, β(2)-microglobulin level, IGHV mutation ratio and splenomegaly/lymphadenopathy in these two subgroups. However, compared with CEP12 negative patients, CEP12 positive patients had higher ratio of FMC7 (23.8% vs 12.7%, χ(2)=4.730, P=0.030), and lower ratio of CD23 (95.2% vs 99.6%, P=0.033). The overall response rates (ORR) in Fludarabine (without Rituximab), Rituximab (with or without Fludarabine) and the traditional chemotherapy group (chlorambucil, CHOP or CHOP-like) were 77.5% (31/40), 84.8% (56/66) and 45.4% (50/110), respectively. The ORR of the traditional chemotherapy group was lower than that of the Fludarabine group and Rituximab group. For CEP12 positive patients, the ORR was inferior to CEP12 negative patients when only using Fludarabine (P<0.05). However, when using Rituximab, the difference could be eliminated, and the ORR was even a little higher in CEP12 negative patients (91.7% vs 81.0%, P=0.306). Compared with CEP12 negative patients, there were no significant differences in progression-free survival (PFS) (χ(2)=0.410, P=0.478) and overall survival (OS) (χ(2)=0.052, P=0.180) for CEP12 positive patients whom the median time from diagnosis to start treatment and OS time was 22.6 (95%CI 15.4-31.7) and 118.5 (95%CI 74.5-162.4) month while the 5-year PFS and OS were (52.9±7.6)% and (74.8±6.6)%. Conclusions: CEP12 positive CLL patients are more common in hepatomegaly and higher level of LDH. The traditional chemotherapy treatment had the lowest efficacy, and the curative effect of single use of fludarabine is not as good as that of CEP12 negative patients, however, when using Ritaximab, the efficacy could be comparable.

ZAP-70 in chronic lymphocytic leukemia: A meta-analysis

BACKGROUND

Recent studies have reported that zeta-chain-associated protein kinase 70 (ZAP-70) expression plays a prognostic role in chronic lymphocytic leukemia (CLL). However, these results remain controversial. Thus, we performed a meta-analysis to clarify the prognostic value of ZAP-70 expression in CLL.

MATERIALS AND METHODS

Relevant studies were searched in PubMed, Embase, Cochrane library, and Web of Science up to January 2018. Clinicopathological features and prognostic data were extracted from the studies. We pooled estimates and 95% confidence intervals (CIs) and estimated the heterogeneity of studies using Mantel-Haenszel or DerSimonian and Laird method.

RESULTS

Twelve studies that included 1956 patients with CLL were eligible for inclusion. The pooled results revealed that increased ZAP-70 expression was significantly associated with poor overall survival (hazard ratio [HR] = 2.48, 95% CI: 1.72-3.59, P = 0.019, I² = 53.0%) and event-free survival (HR = 4.17, 95% CI: 2.17-8.01, P = 0.014, I² = 68.2%) in a random-effects model with significant heterogeneity. Clinicopathological analysis demonstrated that ZAP-70 expression was significantly associated with unmutated immunoglobulin heavy-chain genes, CD38 expression, serum β-2 microglobulin, and lymphocyte doubling time.

CONCLUSIONS

Our findings indicated that ZAP-70 was a strong prognostic biomarker for patients with CLL.

NOTCH1 mutation and its prognostic significance in Chinese chronic lymphocytic leukemia: a retrospective study of 317 cases

The proto-oncogene NOTCH1 is frequently mutated in around 10% of patients with chronic lymphocytic leukemia (CLL). This study analyzed NOTCH1 mutation status of 317 Chinese patients with CLL by Sanger sequencing. The frequencies of NOTCH1 mutation in the PEST (proline (P), glutamic acid (E), serine (S), threonine (T)-rich protein sequence) domain and the 3' untranslated regions (UTR) were 8.2% and 0.9%, with the most frequent mutation being c.7541_7542delCT and c.*371A>G, respectively. Clinical and biological associations were determined including NOTCH1 mutations with advanced stage (Binet stage, P = 0.010), unmutated immunoglobulin heavy-chain variable region (IGHV) gene (P < 0.001) and trisomy 12 (+12) (P = 0.014). NOTCH1-mutated patients had lower CD20 expression intensity than NOTCH1-unmutated patients (P = 0.029). In addition, NOTCH1-mutated patients had shorter overall survival (OS) (P = 0.002) and treatment-free survival (TFS) (P = 0.002) than NOTCH1-unmutated patients, especially for patients with NOTCH1 c.7541_7542delCT and/or c.*371A>G mutations. Patients with both mutated NOTCH1 and unmutated IGHV had shorter OS (P < 0.001) and TFS (P < 0.001) than those with unmutated NOTCH1 or mutated IGHV. These data provide a comprehensive view of the clinical relevance and prognostic impact of NOTCH1 mutations on Chinese patients with CLL.

iwCLL guidelines for diagnosis, indications for treatment, response assessment, and supportive management of CLL

The previous edition of the consensus guidelines of the International Workshop on Chronic Lymphocytic Leukemia (iwCLL), published in 2008, has found broad acceptance by physicians and investigators caring for patients with CLL. Recent advances including the discovery of the genomic landscape of the disease, the development of genetic tests with prognostic relevance, and the detection of minimal residual disease (MRD), coupled with the increased availability of novel targeted agents with impressive efficacy, prompted an international panel to provide updated evidence- and expert opinion-based recommendations. These recommendations include a revised version of the iwCLL response criteria, an update on the use of MRD status for clinical evaluation, and recommendations regarding the assessment and prophylaxis of viral diseases during management of CLL.

ImmunoPET imaging of CD38 in murine lymphoma models using 89Zr-labeled daratumumab

PURPOSE

CD38 is considered a potential biomarker for multiple myeloma (MM) and has shown a strong link with chronic lymphocytic leukemia due to high and uniform expression on plasma cells. In vivo evaluation of CD38 expression may provide useful information about lesion detection and prognosis of treatment in MM. In this study, immunoPET imaging with ⁸⁹Zr-labeled daratumumab was used for differentiation of CD38 expression in murine lymphoma models to provide a potential non-invasive method for monitoring CD38 in the clinic.

METHODS

Daratumumab was radiolabeled with ⁸⁹Zr (t_1/2 = 78.4 h) via conjugation with desferrioxamine (Df). After Western blot (WB) was used to screen CD38 expression in five lymphoma cell lines, flow cytometry and cellular binding assays were performed to test the binding ability of labeled or conjugated daratumumab with CD38 in vitro. PET imaging and biodistribution studies were performed to evaluate CD38 expression after injection of ⁸⁹Zr-Df-daratumumab. ⁸⁹Zr-Df-IgG was also evaluated as a non-specific control group in the Ramos model. Finally, CD38 expression in tumor tissues was verified by histological analysis.

RESULTS

Using WB screening, the Ramos cell line was found to express the highest level of CD38 while the HBL-1 cell line had the lowest expression. Df-conjugated and ⁸⁹Zr-labeled daratumumab displayed similar high binding affinities with Ramos cells. PET imaging of ⁸⁹Zr-Df-daratumumab showed a high tumor uptake of up to 26.6 ± 8.0 %ID/g for Ramos at 120 h post-injection, and only up to 6.6 ± 2.9 %ID/g for HBL-1 (n = 4). Additionally, ⁸⁹Zr-Df-IgG demonstrated a low tumor uptake in the Ramos model (only 4.3 ± 0.8 %ID/g at 120 h post-injection). Ex vivo biodistribution studies showed similar trends with imaging results. Immunofluorescence staining of tumor tissues verified higher CD38 expression of Ramos than that of HBL-1.

CONCLUSIONS

The role of ⁸⁹Zr-Df-daratumumab was investigated for evaluating CD38 expression in lymphoma models non-invasively and was found to be to a promising imaging agent of CD38-positive hematological diseases such as MM in future clinical applications.

Using prognostic models in CLL to personalize approach to clinical care: Are we there yet?

Four decades ago, two staging systems were developed to help stratify CLL into different prognostic categories. These systems, the Rai and the Binet staging, depended entirely on abnormal exam findings and evidence of anemia and thrombocytopenia. Better understanding of biologic, genetic, and molecular characteristics of CLL have contributed to better appreciating its clinical heterogeneity. New prognostic models, the GCLLSG prognostic index and the CLL-IPI, emerged. They incorporate biologic and genetic information related to CLL and are capable of predicting survival outcomes and cases anticipated to need therapy earlier in the disease course. Accordingly, these newer models are helping develop better informed surveillance strategies and ultimately tailor treatment intensity according to presence (or lack thereof) of certain prognostic markers. This represents a step towards personalizing care of CLL patients. We anticipate that as more prognostic factors continue to be identified, the GCLLSG prognostic index and CLL-IPI models will undergo further revisions.