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Summary: We explored the relevance of genomic microarrays (GM) in the refinement of prognosis in newly diagnosed low‐risk chronic lymphocytic leukaemia (CLL) patients as defined by isolated del(13q) or no lesions by a standard 4 probe fluorescence in situ hybridization (FISH) analysis. Compared to FISH, additional lesions were detected by GM in 27 of the 119 patients (22.7%). The concordance rate between FISH and GM was 87.4%. Discordant results between cytogenetic banding analysis (CBA) and GM were observed in 45/119 cases (37.8%) and were mainly due to the intrinsic characteristics of each technique. The presence of additional lesions by GM was associated with age > 65 years (p = 0.047), advanced Binet stage (p = 0.001), CLL‐IPI score (p < 0.001), a complex karyotype (p = 0.004) and a worse time‐to‐first treatment in multivariate analysis (p = 0.009). Additional lesions by GM were also significantly associated with a worse time‐to‐first treatment in the subset of patients with wild‐type TP53 and mutated IGHV (p = 0.025). In CLL patients with low‐risk features, the presence of additional lesions identified by GM helps to identify a subset of patients with a worse outcome that could be proposed for a risk‐adapted follow‐up and for early treatment including targeted agents within clinical trials. [ABSTRACT FROM AUTHOR]

Liquid biopsy has advantages over tissue biopsy, but also some technical limitations that hinder its wide use in clinical applications. In this study, we aimed to evaluate the usefulness of liquid biopsy for the clinical management of patients with advanced-stage oncogene-addicted non-small-cell lung adenocarcinomas. The investigation was conducted on a series of cases—641 plasma samples from 57 patients—collected in a prospective consecutive manner, which allowed us to assess the benefits and limitations of the approach in a real-world clinical context. Thirteen samples were collected at diagnosis, and the additional samples during the periodic follow-up visits. At diagnosis, we detected mutations in ctDNA in 10 of the 13 cases (77%). During follow-up, 36 patients progressed. In this subset of patients, molecular analyses of plasma DNA/RNA at progression revealed the appearance of mutations in 29 patients (80.6%). Mutations in ctDNA/RNA were typically detected an average of 80 days earlier than disease progression assessed by RECIST or clinical evaluations. Among the cases positive for mutations, we observed 13 de novo mutations, responsible for the development of resistance to therapy. This study allowed us to highlight the advantages and disadvantages of liquid biopsy, which led to suggesting algorithms for the use of liquid biopsy analyses at diagnosis and during monitoring of therapy response. [ABSTRACT FROM AUTHOR]

Abstract Background Fludarabine, is one of the most active single agents in the treatment of chronic lymphocytic leukemia (CLL). Over time, however, virtually all CLL patients become fludarabine-refractory. To elucidate whether microRNAs are involved in the development of fludarabine resistance, we analyzed the expression of 723 human miRNAs before and 5-days after fludarabine mono-therapy in 17 CLL patients which were classified as responder or refractory to fludarabine treatment based on NCI criteria. Results By comparing the expression profiles of these two groups of patients, we identified a microRNA signature able to distinguish refractory from sensitive CLLs. The expression of some microRNAs was also able to predict fludarabine resistance of 12 independent CLL patients. Among the identified microRNAs, miR-148a, miR-222 and miR-21 exhibited a significantly higher expression in non-responder patients either before and after fludarabine treatment. After performing messenger RNA expression profile of the same patients, the activation of p53-responsive genes was detected in fludarabine responsive cases only, therefore suggesting a possible mechanism linked to microRNA deregulation in non-responder patients. Importantly, inhibition of miR-21 and miR-222 by anti-miRNA oligonucleotides induced a significant increase in caspase activity in fludarabine-treated p53-mutant MEG-01 cells, suggesting that miR-21 and miR-222 up-regulation may be involved in the establishment of fludarabine resistance. Conclusions This is the first report that reveals the existence of a microRNA profile that differentiate refractory and sensitive CLLs, either before and after fludarabine mono-therapy. A p53 dysfunctional pathway emerged in refractory CLLs and could contribute in explaining the observed miRNA profile. Moreover, this work indicates that specific microRNAs can be used to predict fludarabine resistance and may potentially be used as therapeutic targets, therefore establishing an important starting point for future studies.

Summary: In a series of 349 patients with chronic lymphocytic leukaemia (CLL), we found lower levels of signalling lymphocytic activation molecule family member 1 (SLAMF1) expression in cases with highly complex karyotypes, as defined by the presence of five or more chromosomal abnormalities (CK5; P < 0·001) and with major chromosomal structural abnormalities (P < 0·001). SLAMF1 downregulation was significantly associated with advanced Binet Stage (P = 0·001), CD38 positivity (P < 0·001), high β2‐microglobulin levels (P < 0·001), immunoglobulin heavy chain variable region gene (IGHV) unmutated status (P < 0·001), 11q deletion (P < 0·001), tumour protein p53 (TP53) disruption (P = 0·011) and higher risk CLL International Prognostic Index categories (P < 0·001). Multivariate analysis showed that downregulated SLAMF1 levels had independent negative prognostic impact on time‐to‐first treatment (P < 0·001) and overall survival (P < 0·001). [ABSTRACT FROM AUTHOR]

Cytopathological analyses of bronchial washings (BWs) collected during fibre‐optic bronchoscopy are often inconclusive for lung cancer diagnosis. To address this issue, we assessed the suitability of conducting molecular analyses on BWs, with the aim to improve the diagnosis and outcome prediction of lung cancer. The methylation status of RASSF1A, CDH1, DLC1 and PRPH was analysed in BW samples from 91 lung cancer patients and 31 controls, using a novel two‐colour droplet digital methylation‐specific PCR (ddMSP) technique. Mutations in ALK, BRAF, EGFR, ERBB2, KRAS, MAP2K1, MET, NRAS, PIK3CA, ROS1 and TP53 and gene fusions of ALK, RET and ROS1 were also investigated, using next‐generation sequencing on 73 lung cancer patients and 14 tumour‐free individuals. Our four‐gene methylation panel had significant diagnostic power, with 97% sensitivity and 74% specificity (relative risk, 7.3; odds ratio, 6.1; 95% confidence interval, 12.7–127). In contrast, gene mutation analysis had a remarkable value for predictive, but not for diagnostic, purposes. Actionable mutations in EGFR, HER2 and ROS1 as well as in other cancer genes (KRAS, PIK3CA and TP53) were detected. Concordance with gene mutations uncovered in tumour biopsies was higher than 90%. In addition, bronchial‐washing analyses permitted complete patient coverage and the detection of additional actionable mutations. In conclusion, BWs are a useful material on which to perform molecular tests based on gene panels: aberrant gene methylation and mutation analyses could be performed as approaches accompanying current diagnostic and predictive assays during the initial workup phase. This study establishes the grounds for further prospective investigation. [ABSTRACT FROM AUTHOR]

In the Local Health Authority (LHA) of Parma, Emilia Romagna, Italy, 16 medical homes were established between 2011 and 2014. The authors implemented a 1-year (January 1, 2015, to December 31, 2015) cross-sectional population-based design to compare utilization and processes of care between medical homes and comparison practices using the Parma LHA administrative health care database. Residents (n = 372 396) attributed to a primary care physician practicing in a medical home as of January 1, 2015, were considered exposed to medical homes. Adjusted rates of emergency department (ED) use (incidence rate ratio [IRR] = 0.86; 95% CI = 0.82-0.90), potentially avoidable ED use (IRR = 0.78; 95% CI = 0.72-0.84), and hospitalization for chronic ambulatory care sensitive conditions (ACSCs; IRR = 0.87, 95% CI = 0.78-0.97) were lower among patients in medical homes. Performance on process of care measures favored the medical home group; however, associations were generally weak. Receipt of care in medical homes in Parma LHA was associated with lower rates of avoidable ED visits and hospitalizations for chronic ACSCs. [ABSTRACT FROM AUTHOR]

Summary: Complex karyotype (CK) is a negative prognostic factor in chronic lymphocytic leukaemia (CLL). However, CK is a heterogeneous cytogenetic category. Unbalanced rearrangements were present in 73·3% of 90 CLL patients with CK (i.e. ≥3 chromosome aberrations in the same clone), and were associated with a shorter overall survival (P = 0·025) and a shorter time to first treatment (P = 0·043) by multivariate analysis. Patients with unbalanced rearrangements presented a distinct mRNA expression profile. In conclusion, CLL patients with unbalanced rearrangements might represent a subset of very high‐risk CLL patients with distinct clinical and biological characteristics. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The article presents a study that involves comparison of quantifying MircoRNA (miRNA) with the QX200 Droplet Digital Polymerase Chain Reaction (ddPCR) system when used with EvaGreen dye-based and TaqMan probe-based assays. The study reveals that both assays can be equally used with the ddPCR system to quantify circulating miRNAs in human plasma and serum. Also the study establishes the basis for using EvaGreen dye-based assays on a ddPCR system for quantifying circulating miRNA biomarkers.

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. [ABSTRACT FROM AUTHOR]

To better define the significance of clonal evolution (CE) including 14q32 translocations involving the immunoglobulin heavy chain gene ( IGH) in chronic lymphocytic leukemia (CLL), 105 patients were analyzed sequentially by fluorescence in situ hybridization (FISH) with the following panel of probes: 13q14/D13S25, 11q22/ ATM, 17p13/ TP53, ##12-centromere and 14q32/ IGH break-apart probe. CE was observed in 15/105 patients after 24-170 months (median 64). Recurring aberrations at CE were 14q32/ IGH translocation in seven patients; other aberrations were 17p −, 11q −, biallelic 13q − and 14q32 deletion. CE was detected in 15/58 pre-treated patients; in contrast, none of 47 untreated patients developed CE ( p < 0.0001). In two cases the appearance of 14q32/ IGH translocation was first detected in the bone marrow (BM) or in the lymph node (LN) and 13-58 months later in the peripheral blood (PB). ZAP70 ++ and high-risk cytogenetics predicted for the occurrence of CE with borderline statistical significance ( p == 0.055 and 0.07, respectively). Shorter time to first treatment (TTT) and time to chemorefractoriness (TTCR) were noted in 15 patients with CE when compared to patients without CE (TTT: 35 vs. 71 months, p == 0.0033 and TTCR: 34 vs. 86 months, p == 0.0046, respectively). Survival after the development of CE was 32 months (standard error 8.5). We arrived at the following conclusions: (i) 14q32/ IGH translocation may represent one of the most frequent aberrations acquired during the natural history of CLL and (ii) it may be detected earlier in BM or LN samples; (iii) CE including 14q32/ IGH translocation occurs in pre-treated patients with short TTT and TTCR; (iii) survival after CE is relatively short. [ABSTRACT FROM AUTHOR]

Background: Fludarabine, is one of the most active single agents in the treatment of chronic lymphocytic leukemia (CLL). Over time, however, virtually all CLL patients become fludarabine-refractory. To elucidate whether microRNAs are involved in the development of fludarabine resistance, we analyzed the expression of 723 human miRNAs before and 5-days after fludarabine mono-therapy in 17 CLL patients which were classified as responder or refractory to fludarabine treatment based on NCI criteria. Results: By comparing the expression profiles of these two groups of patients, we identified a microRNA signature able to distinguish refractory from sensitive CLLs. The expression of some microRNAs was also able to predict fludarabine resistance of 12 independent CLL patients. Among the identified microRNAs, miR-148a, miR-222 and miR-21 exhibited a significantly higher expression in non-responder patients either before and after fludarabine treatment. After performing messenger RNA expression profile of the same patients, the activation of p53- responsive genes was detected in fludarabine responsive cases only, therefore suggesting a possible mechanism linked to microRNA deregulation in non-responder patients. Importantly, inhibition of miR-21 and miR-222 by antimiRNA oligonucleotides induced a significant increase in caspase activity in fludarabine-treated p53-mutant MEG-01 cells, suggesting that miR-21 and miR-222 up-regulation may be involved in the establishment of fludarabine resistance. Conclusions: This is the first report that reveals the existence of a microRNA profile that differentiate refractory and sensitive CLLs, either before and after fludarabine mono-therapy. A p53 dysfunctional pathway emerged in refractory CLLs and could contribute in explaining the observed miRNA profile. Moreover, this work indicates that specific microRNAs can be used to predict fludarabine resistance and may potentially be used as therapeutic targets, therefore establishing an important starting point for future studies. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which is concerned with the case of a patient with BCR/ABL1-positive acute leukemia who relapsed with BCR/ABL1-negative acute lymphoblastic leukemia.

The complex karyotype (CK) is an established negative prognostic marker in a number of haematological malignancies. After the introduction of effective mitogens, a growing body of evidence has suggested that the presence of 3 or more aberrations by conventional banding analysis (CBA) is associated with an unfavorable outcome in chronic lymphocytic leukemia (CLL). Thus, the importance of CBA was recognized by the 2018 guidelines of the International Workshop on CLL, which proposed the introduction of CBA in clinical trials to validate the value of karyotype aberrations. Indeed, a number of observational studies showed that cytogenetic aberrations and, particularly, the CK may have a negative independent impact on objective outcome measures (i.e. time to first treatment, progression free survival, time to chemorefractoriness and overall survival) both in patients treated with chemoimmunotherapy and, possibly, in patients receiving novel mechanism-based treatment. Here, we set out to present the scientific evidence supporting the significance of CK as a prognostic marker in CLL and to discuss the biological basis showing that the CK is a consequence of genomic instability., Competing Interests: CONFLICTS OF INTEREST The authors declare no conflicts of interest.

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.

Objectives: To evaluate the micro-RNA (miRNA) expression profile in patients with early psoriatic arthritis (PsA) in order to assess the role of miRNAs as potential PsA biomarkers., Methods: The expression of 723 mature miRNAs in peripheral blood mononuclear cells of early PsA patients in comparison with early-rheumatoid arthritis (ERA) patients and healthy controls (HC) was evaluated using a miRNA microarray. All patients had active disease and were naïve from treatment. The results were validated for a specific miRNA (miR-21-5p) in the entire series of patients plus an additional group of early PsA, ERA and HC using droplet digital PCR., Results: In PsA, microarray analysis revealed a distinct pattern of 19 (vs. HC) and 48 (vs. ERA) deregulated miRNAs (p<0.05). The significant up-regulation of miR-21-5p both in early PsA and in ERA in comparison with HC was validated and confirmed. In PsA, miR-21-5p was found significantly down regulated after 12 weeks of therapy, which significantly correlated with the reduction of DAPSA score., Conclusions: In early PsA, a 19- (vs. HC) and 48- (vs. ERA) miRNA signature was identified. A differential expression of miRNAs in patients with active disease makes them attractive biomarkers of psoriatic disease. MiR-21-5p was found up-regulated both in early PsA and ERA, a finding which highlights its role in the inflammatory process in general and its potential role as a therapeutic target in different inflammatory disorders. A potential role of miR-21-5p as a response to treatment biomarker in early PsA has been identified.

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.

Background: The Comunity Health Centre (CHC) primary care model is a team-based health care delivery model intended to provide comprehensive and continuous medical care to patients within a defined community. The CHC, Case della Salute in Italian, model was introduced in the Emilia-Romagna Region in 2010., Methods: We present updated data on the implementation on the CHC Case della Salute primary care model in the Emilia-Romagna Region., Results: There are 67 operating CHCs in Emilia-Romagna (update March 2015); 26 small (39%), 24 medium (36%) and 17 large (25%). Since 2011 the number of operating CHCs has increased by 60%, reaching 55% of the target planned CHCs (n. = 122). There is, on average, one running CHC per 66.524 inhabitants. 16% of total general practitioners (GPs) and 8.4% of total family paediatricians working in Emilia-Romagna have their practice in CHCs. CHCs offer primary and specialist integrated care, prevention services, health education and social care., Discussion: Although preliminary results suggest CHCs have fostered primary care's quality and efficiency, more research is needed to assess their impact on improving clinical, social and economic outcomes.

The hypothesis to use microRNAs (miRNAs) circulating in the blood as cancer biomarkers was formulated some years ago based on promising initial results. After some exciting discoveries, however, it became evident that the accurate quantification of cell-free miRNAs was more challenging than expected. Difficulties were linked to the strong impact that many, if not all, pre- and post- analytical variables have on the final results. In this study, we used currently available high-throughput technologies to identify miRNAs present in plasma and serum of patients with breast, colorectal, lung, thyroid and melanoma tumors, and healthy controls. Then, we assessed the absolute level of nine different miRNAs (miR-320a, miR-21-5p, miR-378a-3p, miR-181a-5p, miR-3156-5p, miR-2110, miR-125a-5p, miR-425-5p, miR-766-3p) in 207 samples from healthy controls and cancer patients using droplet digital PCR (ddPCR) technology. We identified miRNAs specifically modulated in one or more cancer types, according to tissue source. The significant reduction of miR-181a-5p levels in breast cancer patients serum was further validated using two independent cohorts, one from Italy (n = 70) and one from US (n = 90), with AUC 0.66 and 0.73 respectively. This study finally powers the use of cell-free miRNAs as cancer biomarkers and propose miR-181a-5p as a diagnostic breast cancer biomarker.

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., (©2014 American Association for Cancer Research.)

The majority of patients with chronic lymphocytic leukemia (CLL) and favorable prognostic features live for long periods without treatment. However, unexpected disease progression is observed in some cases. In a cohort of untreated CD38- CLL patients with normal FISH or isolated 13q- we found that, by fluorescence in situ hybridization (FISH), 16/28 cases presented, within immunomagnetic sorted CD38+ cells, genetic lesions undetectable in the CD38- fraction. These patients showed a shorter time to first treatment (TTFT, p=0.0162) in comparison to cases without FISH lesions in CD38+ cells. Patients with FISH abnormalities in CD38+ cells showed a distinctive microRNA profile, characterized by the down-regulation of miR-125a-5p both in the CD38- and CD38+ populations. In an independent cohort of 71 consecutive untreated CD38- CLL with normal FISH or isolated 13q-, a lower miR125a-5p expression was associated with a shorter TTFT both in univariate and multivariate analysis (p=0.003 and 0.016, respectively) and with a higher prevalence of mutations (7/12 vs 0/8, p=0.015) as assessed by next-generation sequencing. In conclusion, our data showed previously unrecognized subclonal heterogeneity within the CD38+ fraction of CD38- CLL patients with low-risk FISH findings and suggested an association between down-regulated miR-125a-5p expression, genetic complexity and worse outcome.

To better define the significance of clonal evolution (CE) including 14q32 translocations involving the immunoglobulin heavy chain gene (IGH) in chronic lymphocytic leukemia (CLL), 105 patients were analyzed sequentially by fluorescence in situ hybridization (FISH) with the following panel of probes: 13q14/D13S25, 11q22/ATM, 17p13/TP53, #12-centromere and 14q32/IGH break-apart probe. CE was observed in 15/105 patients after 24-170 months (median 64). Recurring aberrations at CE were 14q32/IGH translocation in seven patients; other aberrations were 17p -, 11q -, biallelic 13q - and 14q32 deletion. CE was detected in 15/58 pre-treated patients; in contrast, none of 47 untreated patients developed CE (p < 0.0001). In two cases the appearance of 14q32/IGH translocation was first detected in the bone marrow (BM) or in the lymph node (LN) and 13-58 months later in the peripheral blood (PB). ZAP70 + and high-risk cytogenetics predicted for the occurrence of CE with borderline statistical significance (p = 0.055 and 0.07, respectively). Shorter time to first treatment (TTT) and time to chemorefractoriness (TTCR) were noted in 15 patients with CE when compared to patients without CE (TTT: 35 vs. 71 months, p = 0.0033 and TTCR: 34 vs. 86 months, p = 0.0046, respectively). Survival after the development of CE was 32 months (standard error 8.5). We arrived at the following conclusions: (i) 14q32/IGH translocation may represent one of the most frequent aberrations acquired during the natural history of CLL and (ii) it may be detected earlier in BM or LN samples; (iii) CE including 14q32/IGH translocation occurs in pre-treated patients with short TTT and TTCR; (iii) survival after CE is relatively short.

Background: Fludarabine, is one of the most active single agents in the treatment of chronic lymphocytic leukemia (CLL). Over time, however, virtually all CLL patients become fludarabine-refractory. To elucidate whether microRNAs are involved in the development of fludarabine resistance, we analyzed the expression of 723 human miRNAs before and 5-days after fludarabine mono-therapy in 17 CLL patients which were classified as responder or refractory to fludarabine treatment based on NCI criteria., Results: By comparing the expression profiles of these two groups of patients, we identified a microRNA signature able to distinguish refractory from sensitive CLLs. The expression of some microRNAs was also able to predict fludarabine resistance of 12 independent CLL patients. Among the identified microRNAs, miR-148a, miR-222 and miR-21 exhibited a significantly higher expression in non-responder patients either before and after fludarabine treatment. After performing messenger RNA expression profile of the same patients, the activation of p53-responsive genes was detected in fludarabine responsive cases only, therefore suggesting a possible mechanism linked to microRNA deregulation in non-responder patients. Importantly, inhibition of miR-21 and miR-222 by anti-miRNA oligonucleotides induced a significant increase in caspase activity in fludarabine-treated p53-mutant MEG-01 cells, suggesting that miR-21 and miR-222 up-regulation may be involved in the establishment of fludarabine resistance., Conclusions: This is the first report that reveals the existence of a microRNA profile that differentiate refractory and sensitive CLLs, either before and after fludarabine mono-therapy. A p53 dysfunctional pathway emerged in refractory CLLs and could contribute in explaining the observed miRNA profile. Moreover, this work indicates that specific microRNAs can be used to predict fludarabine resistance and may potentially be used as therapeutic targets, therefore establishing an important starting point for future studies.