Genetic subclonal complexity and miR125a-5p down-regulation identify a subset of patients with inferior outcome in low-risk CLL patients

Evaluation of miRNA 223/125a and COBLL1 Expressions and ROR-1 Levels as Reliable Markers in B- chronic Lymphocytic Leukemia

BACKGROUND

miRNA 223 /125a and Cordon-bleu Protein Like 1 (COBLL1) are novel biomarkers that can predict prognosis and guide treatment decisions in patients with chronic lymphocytic leukemia (CLL). Also, there is a growing interest in CLL monitoring based on flow cytometry of receptor tyrosine kinase-like orphan receptor-1 (ROR-1).  Objective: This study aimed to evaluate the relationship between miRNA 223 /125a and COBLL1 expressions and ROR-1 expression in patients with CLL. Also, the study evaluated the relationship between the expression of these biomarkers with tumor staging and cancer progression.

METHODS

Our study included 40 patients newly diagnosed with B-CLL. In peripheral blood (PB), miRNA 223/125a and COBLL1 expressions were detected by real-time polymerase chain reaction (real-time PCR) and ROR-1 percentage was detected by flow cytometry before and after treatment.  Results: High level of COBLL1 expression was statistically significantly associated with high ROR-1 percentage expression (P= 0.03). However, a high level of miRNA 223/125a expression was statistically significantly associated with low ROR-1 percentage expression (P=0.002). The sensitivity and specificity of ROR-1 as a predictor of high WBCs count after treatment were 96.6 and 81.1%, respectively. There was a statistically significant reduction of ROR-1 percentage after treatment compared to before treatment (P <0.001).

CONCLUSION

ROR-1 percentage expression can be considered a possible prognostic predictor in CLL along with miRNA 223/125a and COBLL1 expressions. This can be explained by the significant correlation between ROR-1 and the studied molecular biomarkers; miRNA 223/125a and COBLL1. In addition, there was a significantly higher ROR-1 percentage in patients with higher WBC counts. Moreover, there was a significant reduction in ROR-1 percentage after treatment.

Evaluation of microRNA-223 and microRNA-125a expression association with STAT3 and Bcl2 genes in blood leukocytes of CLL patients: a case-control study

OBJECTIVE

In chronic lymphocytic leukemia (CLL), lack of expression or dysregulation of some special miRs disrupts apoptosis of malignant cells; thereby miR expression can enhance cell proliferation, disease progression and decrease patient survival.

RESULTS

30 CLL patients and 20 healthy individuals participated in the study. RNA was extracted to evaluate the expression of miR-125, miR-223, BCL-2 and signal transducer and transcription 3 activator (STAT3) genes; quantitative Real Time- PCR (Q-RT-PCR) was performed. MiR-125a and miR-223 expression decreased in the patients compared to the control group (P-Value:0.001). BCL-2 and STAT3 which are the target genes of these two miRs, showed increased expression, in the patients compared to the control subjects (P-Value: 0.001 and P-Value: 0.64 respectively). A significant reverse relationship was found between miR-125a and BCl-2 expression and WBC count. Significantly, miR-223 expression was associated with smoking in patients (P-Value: 0.007). Also, these miRs may have regulatory effects by controlling white blood cell (WBC) production based on the inverse correlation with WBC count and hemoglobin (Hb) concentration. Finally, miR-223 can be used as a prognostic factor in CLL patients; miR-125a may be useful for evaluating the therapeutic approaches based on the inverse link with BCl-2.

miR-125a-5p Functions as Tumor Suppressor microRNA And Is a Marker of Locoregional Recurrence And Poor prognosis in Head And Neck Cancer

MicroRNAs (miRNAs) are short single-stranded RNAs, measuring 21 to 23 nucleotides in length and regulate gene expression at the post-transcriptional level through mRNA destabilization or repressing protein synthesis. Dysregulation of miRNAs can lead to tumorigenesis through changes in regulation of key cellular processes such as cell proliferation, cell survival, and apoptosis. miR-125a-5p has been implicated as a tumor suppressor miRNA in malignancies such as non-small cell lung cancer and colon cancer. However, the role of miR-125a-5p has not been fully investigated in head and neck squamous cell carcinoma (HNSCC). We performed microRNA microarray profiling of HNSCC tumor samples obtained from a prospective clinical trial evaluating the role of postoperative radiotherapy in head and neck cancer. We also mined through The Cancer Genome Atlas to evaluate expression and survival data. Biological experiments, including cell proliferation, flow cytometry, cell migration and invasion, clonogenic survival, and fluorescent microscopy, were conducted using HN5 and UM-SCC-22B cell lines. miR-125a-5p downregulation was associated with recurrent disease in a panel of high-risk HNSCC and then confirmed poor survival associated with low expression in HNSCC via the Cancer Genome Atlas, suggesting that miR-125a-5p acts as a tumor suppressor miRNA. We then demonstrated that miR-125a-5p regulates cell proliferation through cell cycle regulation at the G₁/S transition. We also show that miR-125a-5p can alter cell migration and modulate sensitivity to ionizing radiation. Finally, we identified putative mRNA targets of miR-125a-5p, including ERBB2, EIF4EBP1, and TXNRD1, which support the tumor suppressive mechanism of miR-125a-5p. Functional validation of ERBB2 suggests that miR-125a-5p affects cell proliferation and sensitivity to ionizing radiation, in part, through ERBB2. Our data suggests that miR-125a-5p acts as a tumor suppressor miRNA, has potential as a diagnostic tool and may be a potential therapeutic target for the management and treatment of squamous cell carcinoma of the head and neck.

An extensive molecular cytogenetic characterization in high-risk chronic lymphocytic leukemia identifies karyotype aberrations and TP53 disruption as predictors of outcome and chemorefractoriness

We investigated whether karyotype analysis and mutational screening by next generation sequencing could predict outcome in 101 newly diagnosed chronic lymphocytic leukemia patients with high-risk features, as defined by the presence of unmutated IGHV gene and/or 11q22/17p13 deletion by FISH and/or TP53 mutations. Cytogenetic analysis showed favorable findings (normal karyotype and isolated 13q14 deletion) in 30 patients, unfavorable (complex karyotype and/or 17p13/11q22 deletion) in 34 cases and intermediate (all other abnormalities) in 36 cases. A complex karyotype was present in 21 patients. Mutations were detected in 56 cases and were associated with unmutated IGHV status (p = 0.040) and complex karyotype (p = 0.047). TP53 disruption (i.e. TP53 mutations and/or 17p13 deletion by FISH) correlated with the presence of ≥ 2 mutations (p = 0.001) and a complex karyotype (p = 0.012). By multivariate analysis, an advanced Binet stage (p < 0.001) and an unfavorable karyotype (p = 0.001) predicted a shorter time to first treatment. TP53 disruption (p = 0.019) and the unfavorable karyotype (p = 0.028) predicted a worse overall survival. A shorter time to chemorefractoriness was associated with TP53 disruption (p = 0.001) and unfavorable karyotype (p = 0.025). Patients with both unfavorable karyotype and TP53 disruption presented a dismal outcome (median overall survival and time to chemorefractoriness of 28.7 and 15.0 months, respectively). In conclusion, karyotype analysis refines risk stratification in high-risk CLL patients and could identify a subset of patients with highly unfavorable outcome requiring alternative treatments.

Identifying High-Risk Chronic Lymphocytic Leukemia: A Pathogenesis-Oriented Appraisal of Prognostic and Predictive Factors in Patients Treated with Chemotherapy with or without Immunotherapy

Chronic lymphocytic leukemia (CLL) displays an extremely variable clinical behaviour. Accurate prognostication and prediction of response to treatment are important in an era of effective first-line regimens and novel molecules for high risk patients. Because a plethora of prognostic biomarkers were identified, but few of them were validated by multivariable analysis in comprehensive prospective studies, we applied in this survey stringent criteria to select papers from the literature in order to identify the most reproducible prognostic/predictive markers. Each biomarker was analysed in terms of reproducibility across the different studies with respect to its impact on time to first treatment (TTFT), progression free survival (PFS), overall survival (OS) and response to treatment. We were able to identify the following biomarkers as the most reliable in guiding risk stratification in the daily clinical practice: 17p-/TP53 mutations, IGHV unmutated configuration, short telomeres and 11q-. However, the method for measuring telomere length was not validated yet and 11q- was predictive of inferior OS only in those patients who did not receive FCR-like combinations. Stage and lymphocytosis were predictive of shorter TTFT and age, high serum thymidine kinase levels and poor performance status were predictive of shorter OS. Using our criteria no parameter was found to independently predict for inferior response to treatment.

Extensive next-generation sequencing analysis in chronic lymphocytic leukemia at diagnosis: clinical and biological correlations

Background

In chronic lymphocytic leukemia (CLL), next-generation sequencing (NGS) analysis represents a sensitive, reproducible, and resource-efficient technique for routine screening of gene mutations.

Methods

We performed an extensive biologic characterization of newly diagnosed CLL, including NGS analysis of 20 genes frequently mutated in CLL and karyotype analysis to assess whether NGS and karyotype results could be of clinical relevance in the refinement of prognosis and assessment of risk of progression. The genomic DNA from peripheral blood samples of 200 consecutive CLL patients was analyzed using Ion Torrent Personal Genome Machine, a NGS platform that uses semiconductor sequencing technology. Karyotype analysis was performed using efficient mitogens.

Results

Mutations were detected in 42.0 % of cases with 42.8 % of mutated patients presenting 2 or more mutations. The presence of mutations by NGS was associated with unmutated IGHV gene (p = 0.009), CD38 positivity (p = 0.010), risk stratification by fluorescence in situ hybridization (FISH) (p < 0.001), and the complex karyotype (p = 0.003). A high risk as assessed by FISH analysis was associated with mutations affecting TP53 (p = 0.012), BIRC3 (p = 0.003), and FBXW7 (p = 0.003) while the complex karyotype was significantly associated with TP53, ATM, and MYD88 mutations (p = 0.003, 0.018, and 0.001, respectively). By multivariate analysis, the multi-hit profile (≥2 mutations by NGS) was independently associated with a shorter time to first treatment (p = 0.004) along with TP53 disruption (p = 0.040), IGHV unmutated status (p < 0.001), and advanced stage (p < 0.001). Advanced stage (p = 0.010), TP53 disruption (p < 0.001), IGHV unmutated status (p = 0.020), and the complex karyotype (p = 0.007) were independently associated with a shorter overall survival.

Conclusions

At diagnosis, an extensive biologic characterization including NGS and karyotype analyses using novel mitogens may offer new perspectives for a better refinement of risk stratification that could be of help in the clinical management of CLL patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s13045-016-0320-z) contains supplementary material, which is available to authorized users.

Chromosome aberrations detected by conventional karyotyping using novel mitogens in chronic lymphocytic leukemia: Clinical and biologic correlations

To clarify whether karyotype aberrations (KA) involving regions not covered by the standard fluorescence in situ hybridization (FISH) panel have independent prognostic relevance, we evaluated KA by conventional cytogenetics in a learning cohort (LC; n = 166) and a validation cohort (VC; n = 250) of untreated chronic lymphocytic leukemia (CLL) patients. In the VC, novel mitogens were used to improve metaphase generation and TP53, NOTCH1, and SF3B1 mutations were assessed. KA undetected by FISH were found in 35 and 35% of the cases in the LC and VC, respectively. In addition to FISH, KA allowed reclassification of 23 and 26% of cases in the LC and VC, respectively, into a higher cytogenetic risk group. By multivariate analysis, both in the LC and VC, KA other than isolated 13q deletion correlated with a shorter time to first treatment (TFT; P < 0.001 and 0.003, respectively), while a complex karyotype predicted a worse overall survival (OS, P = 0.015 and 0.010, respectively). In the VC, where a comprehensive biologic assessment was performed, a shorter TFT was also predicted by stage (P < 0.001), IGHV mutational status (P = 0.05), and del(17p)/TP53 mutations (P = 0.033) while stage (P = 0.023) and del(17p)/TP53 mutations (P = 0.024) independently predicted a shorter OS. FISH results did not independently impact on TFT and OS, in the LC and VC cohorts; this was also the case for NOTCH1 and SF3B1 mutations in the VC. We suggest that in CLL, conventional karyotyping with novel mitogens could be more effective than FISH for the detection of KA allowing for a more precise refinement of prognosis.

microRNAome expression in chronic lymphocytic leukemia: comparison with normal B-cell subsets and correlations with prognostic and clinical parameters

PURPOSE

Despite its indolent nature, chronic lymphocytic leukemia (CLL) remains an incurable disease. To establish the potential pathogenic role of miRNAs, the identification of deregulated miRNAs in CLL is crucial.

EXPERIMENTAL DESIGN

We analyzed the expression of 723 mature miRNAs in 217 early-stage CLL cases and in various different normal B-cell subpopulations from tonsils and peripheral blood.

RESULTS

Our analyses indicated that CLL cells exhibited a miRNA expression pattern that was most similar to the subsets of antigen-experienced and marginal zone-like B cells. These normal subpopulations were used as reference to identify differentially expressed miRNAs in comparison with CLL. Differences related to the expression of 25 miRNAs were found to be independent from IGHV mutation status or cytogenetic aberrations. These differences, confirmed in an independent validation set, led to a novel comprehensive description of miRNAs potentially involved in CLL. We also identified miRNAs whose expression was distinctive of cases with mutated versus unmutated IGHV genes or cases with 13q, 11q, and 17p deletions and trisomy 12. Finally, analysis of clinical data in relation to miRNA expression revealed that miR26a, miR532-3p, miR146-5p, and miR29c* were strongly associated with progression-free survival.

CONCLUSION

This study provides novel information on miRNAs expressed by CLL and normal B-cell subtypes, with implication on the cell of origin of CLL. In addition, our findings indicate a number of deregulated miRNAs in CLL, which may play a pathogenic role and promote disease progression. Collectively, this information can be used for developing miRNA-based therapeutic strategies in CLL.

Modern treatment in chronic lymphocytic leukemia: impact on survival and efficacy in high-risk subgroups

Treatment of chronic lymphocytic leukemia (CLL) has dramatically changed over the last years, with significant improvement in overall survival (OS) and increased efficacy in genetically defined "high-risk" disease. Besides prospective clinical trials usually enrolling young and fit patients, retrospective studies were performed comparing the outcome of patients belonging to different age groups and showing longer survival in patients diagnosed in the most recent periods. In patients younger than 70 years the 10-year relative survival was 43-53% in the 1980s as compared with 59-63% in the 2000s. Likewise, the 10-year relative survival in patients >70 years was 22-42% in the 1980s and 46-55% in the 2000s. Improved outcome derived in part by the introduction of effective regimens in genetically defined "high-risk" disease (i.e., 17p-, 11q-, TP53, NOTCH1, SF3B1 mutations), especially in the younger and/or fit patients. The unfavorable prognostic significance of 11q- was overcome by chemoimmunotherapy. High-dose steroids with anti-CD52 appeared to improve the response rate in 17p-/TP53 mutated cases and allogeneic transplantation achieved prolonged disease control irrespective of high-risk disease. Further improvement is being generated by the new anti-CD20 obinutuzumab in the elderly and by mechanism-based treatment using kinase-targeting agents or anti-BCL2 molecules yielding high-response rate and impressive progression-free survival in the chemorefractory setting as well as in previously untreated patients.