Direct-acting antiviral agents for hepatitis C virus-mixed cryoglobulinaemia: dissociated virological and haematological responses.

The hepatitis C virus-positive (HCV+) mixed cryoglobulinaemia (MC) is associated with haematological alterations such as monoclonal B-cell lymphocytosis or non-Hodgkin lymphomas (NHLs). Antiviral therapy for MC, based on interferon and ribavirin, has been shown to be able to eliminate the viral replication as well as the B-cell monoclonal alterations. Many studies have reported the efficacy of direct-acting antivirals (DAAs) in the treatment of HCV+ MC. However, some authors noticed the persistence of haematological diseases despite HCV eradication. To verify the effects of DAAs on B-cell proliferation, we evaluated 67 patients with HCV+ MC. Six patients had an overt NHL and 30% had monoclonal B-lymphocytosis. In 20% of the patients, the mutation L265P of the myeloid differentiation factor 88 (MYD88) gene was detected in peripheral blood. All patients had negative HCV viraemia at week 12; one had a breakthrough, while two cases relapsed. A complete clinical response of vasculitis was seen in 60% of the patients. Among the six patients with NHL, one showed a complete response, whereas in the others there were no changes in the number and size of the nodes. Among the patients carrying a clonal population in peripheral blood, only 22% became negative. These data indicate that DAAs are not able to eliminate the clonal alterations induced by HCV in a large proportion of cases.

Molecular prediction of durable remission after first-line fludarabine-cyclophosphamide-rituximab in chronic lymphocytic leukemia.

Fludarabine, cyclophosphamide, and rituximab (FCR) has represented a significant treatment advancement in chronic lymphocytic leukemia (CLL). In the new scenario of targeted agents, there is an increasing interest in identifying patients who gain the maximum benefit from FCR. In this observational multicenter retrospective analysis of 404 CLL patients receiving frontline FCR, the combination of three biomarkers that are widely tested before treatment (IGHV mutation status, 11q deletion and 17p deletion; available in 80% of the study cohort) allowed to identify a very low-risk category of patients carrying mutated IGHV genes but neither 11q or 17p deletion that accounted for 28% of all cases. The majority of very low-risk patients (71%) remained free of progression after treatment and their hazard of relapse decreased after 4 years from FCR. The life expectancy of very low-risk patients (91% at 5 years) was superimposable to that observed in the matched normal general population, indicating that neither the disease nor complications of its treatment affected survival in this favorable CLL group. These findings need a prospective validation and may be helpful for the design of clinical trials aimed at comparing FCR to new targeted treatments of CLL, and, possibly, for optimized disease management.

Low-dose radiotherapy in diffuse large B-cell lymphoma.

Low-dose radiotherapy (LDRT) given in 2 × 2 Gy is a highly effective and safe treatment for palliation of indolent lymphomas. Otherwise, very little regarding the use of LDRT for diffuse large B-cell lymphoma (DLBCL) has been investigated. We designed a phase 2 trial of LDRT in patients with DLBCL with indication for palliative radiation. Low-dose radiotherapy was administered on symptomatic areas only. Clinical response was assessed 21 days after LDRT and defined as reduction >50% of maximum diameter of the radiated lesions. Quality of life was scored by the European Organisation for Research and Treatment of Cancer QLQ-C30 questionnaire. Tumor subtype (germinal center B-cell type versus activated B-cell type) and the presence of TP53 mutations in pathologic specimens of the target lesion were also evaluated. Twenty-three of twenty-five radiated patients were evaluable for response, and 2 died of disease before the visit at 21 days. The overall response rate was 70% (16 of 23 patients), with 7 complete responses and 9 partial responses (mean duration of response, 6 months; range, 1-39 months). Fifteen patients answered to the QLQ-C30 questionnaires, and an improved quality of life was documented in 9 cases. TP53 mutations were detected in 2 of 6 (33%) nonresponders and in none of the responders (P = .12). Germinal center B-cell type responded better than activated B-cell type (response rate was 83% and 29%, respectively, P = .01). These findings indicate that LDRT is effective for palliation in patients with DLBCL.

Integrated mutational and cytogenetic analysis identifies new prognostic subgroups in chronic lymphocytic leukemia.

The identification of new genetic lesions in chronic lymphocytic leukemia (CLL) prompts a comprehensive and dynamic prognostic algorithm including gene mutations and chromosomal abnormalities and their changes during clonal evolution. By integrating mutational and cytogenetic analysis in 1274 CLL samples and using both a training-validation and a time-dependent design, 4 CLL subgroups were hierarchically classified: (1) high-risk, harboring TP53 and/or BIRC3 abnormalities (10-year survival: 29%); (2) intermediate-risk, harboring NOTCH1 and/or SF3B1 mutations and/or del11q22-q23 (10-year survival: 37%); (3) low-risk, harboring +12 or a normal genetics (10-year survival: 57%); and (4) very low-risk, harboring del13q14 only, whose 10-year survival (69.3%) did not significantly differ from a matched general population. This integrated mutational and cytogenetic model independently predicted survival, improved CLL prognostication accuracy compared with FISH karyotype (P < .0001), and was externally validated in an independent CLL cohort. Clonal evolution from lower to higher risk implicated the emergence of NOTCH1, SF3B1, and BIRC3 abnormalities in addition to TP53 and 11q22-q23 lesions. By taking into account clonal evolution through time-dependent analysis, the genetic model maintained its prognostic relevance at any time from diagnosis. These findings may have relevant implications for the design of clinical trials aimed at assessing the use of mutational profiling to inform therapeutic decisions.

Association between molecular lesions and specific B-cell receptor subsets in chronic lymphocytic leukemia.

Genetic lesions and B-cell receptor (BCR) signaling are both oncogenic drivers in chronic lymphocytic leukemia (CLL). However, scant data are available on preferential associations between specific genetic alterations and stereotyped BCR subsets. By analyzing 1419 cases, 2 CLL subsets (2 and 8) harboring stereotyped BCR are enriched in specific molecular alterations influencing disease course. SF3B1 mutations are the genetic hallmark of IGHV3-21-CLL belonging to subset 2 (52%) but are evenly represented in nonstereotyped IGHV3-21-CLL. Trisomy 12 (87%) and NOTCH1 mutations (62%) characterize IGHV4-39-CLL belonging to subset 8 but occur with the expected frequency in IGHV4-39-CLL with heterogeneous BCR. Clinically, co-occurrence of SF3B1 mutations and subset 2 BCR configuration prompts disease progression in IGHV3-21-CLL, whereas cooperation between NOTCH1 mutations, +12, and subset 8 BCR configuration invariably primes CLL transformation into Richter syndrome. These findings provide a proof of concept that specific stereotyped BCR may promote or select molecular lesions influencing outcome.

Mutations of NOTCH1 are an independent predictor of survival in chronic lymphocytic leukemia.

Analysis of the chronic lymphocytic leukemia (CLL) coding genome has recently disclosed that the NOTCH1 proto-oncogene is recurrently mutated at CLL presentation. Here, we assessed the prognostic role of NOTCH1 mutations in CLL. Two series of newly diagnosed CLL were used as training (n = 309) and validation (n = 230) cohorts. NOTCH1 mutations occurred in 11.0% and 11.3% CLL of the training and validation series, respectively. In the training series, NOTCH1 mutations led to a 3.77-fold increase in the hazard of death and to shorter overall survival (OS; P < .001). Multivariate analysis selected NOTCH1 mutations as an independent predictor of OS after controlling for confounding clinical and biologic variables. The independent prognostic value of NOTCH1 mutations was externally confirmed in the validation series. The poor prognosis conferred by NOTCH1 mutations was attributable, at least in part, to shorter treatment-free survival and higher risk of Richter transformation. Although NOTCH1 mutated patients were devoid of TP53 disruption in more than 90% cases in both training and validation series, the OS predicted by NOTCH1 mutations was similar to that of TP53 mutated/deleted CLL. NOTCH1 mutations are an independent predictor of CLL OS, tend to be mutually exclusive with TP53 abnormalities, and identify cases with a dismal prognosis.

Final results of a multicenter trial addressing role of CSF flow cytometric analysis in NHL patients at high risk for CNS dissemination.

This prospective study compared diagnostic and prognostic value of conventional cytologic (CC) examination and flow cytometry (FCM) of baseline samples of cerebrospinal fluid (CSF) in 174 patients with newly diagnosed aggressive non-Hodgkin lymphoma (NHL). FCM detected a neoplastic population in the CSF of 18 of 174 patients (10%), CC only in 7 (4%; P < .001); 11 patients (14%) were discordant (FCM(+)/CC(-)). At a median follow-up of 46 months, there were 64 systemic progressions and 10 CNS relapses, including 2 patients with both systemic and CNS relapses. Two-year progression-free and overall survival were significantly higher in patients with FCM(-) CSF (62% and 72%) compared with those FCM(+) CSF (39% and 50%, respectively), with a 2-year CNS relapse cumulative incidence of 3% (95% confidence interval [CI], 0-7) versus 17% (95% CI, 0-34; P = .004), respectively. The risk of CNS progression was significantly higher in FMC(+)/CC(-) versus FCM(-)/CC(-) patients (hazard ratio = 8.16, 95% CI, 1.45-46). In conclusion, FCM positivity in the CSF of patients with high-risk NHL is associated with a significantly higher CNS relapse risk and poorer outcome. The combination of IV drugs with a higher CNS bioavailability and intrathecal chemotherapy is advisable to prevent CNS relapses in FCM(+) patients.

NOTCH1 mutations identify a chronic lymphocytic leukemia patient subset with worse prognosis in the setting of a rituximab-based induction and consolidation treatment.

Induction therapy with fludarabine followed by rituximab and consolidation plus maintenance with rituximab improved response duration (RD) and overall survival (OS) in our patients with chronic lymphocytic leukemia (CLL). The aim of our study was to investigate the clinical impact of NOTCH1 mutations in this setting of patients. The study included 123 progressive CLL patients homogeneously assigned to first-line induction treatment with fludarabine followed by rituximab. Fifty-nine patients either in complete remission (CR) minimal residual disease positive (MRD+) after induction (n = 39) or in partial remission (PR, n = 20) underwent consolidation/maintenance therapy with rituximab. Sixteen patients in CR MRD + or PR underwent observation only. The presence of NOTCH1 mutations was investigated by amplification refractory mutation system (ARMS) PCR and by Sanger sequencing. NOTCH1 mutations occurred in 20 out of 123 (16.3 %) cases. Consolidated patients showed longer OS than unconsolidated patients (p = 0.030). Both NOTCH1 mutated and CR MRD+ or PR NOTCH1 mutated patients showed significantly shorter OS after treatment (p = 0.00014 and p = 0.0021, respectively). Moreover, NOTCH1 wild-type consolidated cases experienced significantly longer RD and OS than NOTCH1 mutated consolidated or not consolidated cases (p = 0.00001 and p = 0.018, respectively). Finally, the independent prognostic impact of NOTCH1 mutations for OS was confirmed in multivariate analysis (p < 0.001). The presence of NOTCH1 mutations identifies a CLL subset with worse prognosis in the setting of a rituximab-based induction and consolidation treatment.

Early reappearance of intraclonal proliferative subpopulations in ibrutinib-resistant chronic lymphocytic leukemia.

The Bruton's tyrosine kinase (BTK) inhibitor ibrutinib represents an effective strategy for treatment of chronic lymphocytic leukemia (CLL), nevertheless about 30% of patients eventually undergo disease progression. Here we investigated by flow cytometry the long-term modulation of the CLL CXCR4dim/CD5bright proliferative fraction (PF), its correlation with therapeutic outcome and emergence of ibrutinib resistance. By longitudinal tracking, the PF, initially suppressed by ibrutinib, reappeared upon early disease progression, without association with lymphocyte count or serum beta-2-microglobulin. Somatic mutations of BTK/PLCG2, detected in 57% of progressing cases, were significantly enriched in PF with a 3-fold greater allele frequency than the non-PF fraction, suggesting a BTK/PLCG2-mutated reservoir resident within the proliferative compartments. PF increase was also present in BTK/PLCG2-unmutated cases at progression, indicating that PF evaluation could represent a marker of CLL progression under ibrutinib. Furthermore, we evidence different transcriptomic profiles of PF at progression in cases with or without BTK/PLCG2 mutations, suggestive of a reactivation of B-cell receptor signaling or the emergence of bypass signaling through MYC and/or Toll-Like-Receptor-9. Clinically, longitudinal monitoring of the CXCR4dim/CD5bright PF by flow cytometry may provide a simple tool helping to intercept CLL progression under ibrutinib therapy.

Multivalent proteoglycan modulation of FGF mitogenic responses in perivascular cells.

Sprouting of angiogenic perivascular cells is thought to be highly dependent upon autocrine and paracrine growth factor stimulation. Accordingly, we report that corneal angiogenesis induced by ectopic FGF implantation is strongly impaired in NG2/CSPG4 proteoglycan (PG) null mice known to harbour a putative deficit in pericyte proliferation/mobilization. Conversely, no significant differences were seen between wild type and knockout corneas when VEGF was used as an angiocrine factor. Perturbed responsiveness of NG2-deficient pericytes to paracrine and autocrine stimulation by several FGFs could be confirmed in cells isolated from NG2 null mice, while proliferation induced by other growth factors was equivalent in wild type and knockout cells. Identical results were obtained after siRNA-mediated knock-down of NG2 in human smooth muscle-like cell lines, as also demonstrated by the decreased levels of FGF receptor phosphorylation detected in these NG2 deprived cells. Binding assays with recombinant proteins and molecular interactions examined on live cells asserted that FGF-2 bound to NG2 in a glycosaminoglycan-independent, core protein-mediated manner and that the PG was alone capable of retaining FGF-2 on the cell membrane for subsequent receptor presentation. The use of dominant-negative mutant cells, engineered by combined transduction of NG2 deletion constructs and siRNA knock-down of the endogenous PG, allowed us to establish that the FGF co-receptor activity of NG2 is entirely mediated by its extracellular portion. In fact, forced overexpression of the NG2 ectodomain in human smooth muscle-like cells increased their FGF-2-induced mitosis and compensated for low levels of FGF receptor surface expression, in a manner equivalent to that produced by overexpression of the full-length NG2. Upon FGF binding, the cytoplasmic domain of NG2 is phosphorylated, but there is no evidence that this event elicits signal transductions that could bypass the FGFR-mediated ones. Pull-down experiments, protein-protein binding assays and flow cytometry FRET coherently revealed an elective ligand-independent association of NG2 with FGFR1 and FGFR3. The NG2 cooperation with these receptors was also corroborated functionally by the outcome of FGF-2 treatments of cells engineered to express diverse NG2/FGFR combinations. Comprehensively, the findings suggest that perivascular NG2 may serve as a dual modulator of the availability/accessibility of FGF at the cell membrane, as well as the resulting FGFR transducing activity.

IGHV gene mutational status and 17p deletion are independent molecular predictors in a comprehensive clinical-biological prognostic model for overall survival prediction in chronic lymphocytic leukemia.

BACKGROUND: Prognostic index for survival estimation by clinical-demographic variables were previously proposed in chronic lymphocytic leukemia (CLL) patients. Our objective was to test in a large retrospective cohort of CLL patients the prognostic power of biological and clinical-demographic variable in a comprehensive multivariate model. A new prognostic index was proposed. METHODS: Overall survival and time to treatment in 620 untreated CLL patients were analyzed retrospectively to evaluate the multivariate independence and predictive power of mutational status of immunoglobulin heavy chain variable gene segments (IGHV), high-risk chromosomal aberration such as 17p or 11q deletions, CD38 and ZAP-70 expression, age, gender, Binet stage, ß2-microglobulin levels, absolute lymphocyte count and number of lymph node regions. RESULTS: IGHV mutational status and 17p deletion were the sole biological variables with independent prognostic relevance in a multivariate model for overall survival, which included easily measurable clinical parameters (Binet staging, ß2-microglobulin levels) and demographics (age and gender). Analysis of time to treatment in Binet A patients below 70 years of age showed that IGHV was the most important predictor. A novel 6-variable clinical-biological prognostic index was developed and internally validated, which assigned 3 points for Binet C stage, 2 points/each for Binet B stage and for age > 65 years, 1 point/each for male gender, high ß2-microglobulin levels, presence of an unmutated IGHV gene status or 17p deletion. Patients were classified at low-risk (score = 0-1; 21%), intermediate-risk (score 2-5; 63% of cases), high-risk (score 6-9; 16% of cases). Projected 5-year overall survival was 98%, 90% and 58% in low-, intermediate- and high-risk groups, respectively. A nomogram for individual patient survival estimation was also proposed. CONCLUSIONS: Data indicate that IGHV mutational status and 17p deletion may be integrated with clinical-demographic variables in new prognostic tools to estimate overall survival.

Cytogenetic and molecular diagnostic characterization combined to postconsolidation minimal residual disease assessment by flow cytometry improves risk stratification in adult acute myeloid leukemia.

A total of 143 adult acute myeloid leukemia (AML) patients with available karyotype (K) and FLT3 gene mutational status were assessed for minimal residual disease (MRD) by flow cytometry. Twenty-two (16%) patients had favorable, 115 (80%) intermediate, and 6 (4%) poor risk K; 19 of 129 (15%) carried FLT3-ITD mutation. Considering postconsolidation MRD status, patients with good/intermediate-risk K who were MRD(-) had 4-year relapse-free survival (RFS) of 70% and 63%, and overall survival (OS) of 84% and 67%, respectively. Patients with good- and intermediate-risk K who were MRD(+) had 4-year RFS of 15% and 17%, and OS of 38% and 23%, respectively (P < .001 for all comparisons). FLT3 wild-type patients achieving an MRD(-) status, had a better outcome than those who remained MRD(+) (4-year RFS, 54% vs 17% P < .001; OS, 60% vs 23%, P = .002). Such an approach redefined cytogenetic/genetic categories in 2 groups: (1) low-risk, including good/intermediate K-MRD(-) with 4-year RFS and OS of 58% and 73%, respectively; and (2) high risk, including poor-risk K, FLT3-ITD mutated cases, good/intermediate K-MRD(+) categories, with RFS and OS of 22% and 17%, respectively (P < .001 for all comparisons). In AML, the integrated evaluation of baseline prognosticators and MRD improves risk-assessment and optimizes postremission therapy.

CD69 is independently prognostic in chronic lymphocytic leukemia: a comprehensive clinical and biological profiling study.

BACKGROUND: CD69 is expressed in several hemopoietic cells and is an early activation marker in chronic lymphocytic leukemia. Chronic lymphocytic leukemia is a clinically heterogeneous disease which needs novel prognostic parameters which can be easily and efficiently managed. DESIGN AND METHODS: We investigated CD69 by flow cytometry in a series of 417 patients affected by chronic lymphocytic leukemia and compared this to other biological and clinical prognosticators. RESULTS: CD69 was associated with Rai stages (P=0.00002), ß(2)-microglobulin (P=0.0005) and soluble CD23 (P<0.0001). CD69 and ZAP-70 (P=0.018) or CD38 (P=0.00015) or immunoglobulin variable heavy chain gene mutations (P=0.0005) were also significantly correlated. Clinically, CD69 positive chronic lymphocytic leukemias received chemotherapy more frequently (74%; P<0.0001), and presented a shorter duration of response after fludarabine plus rituximab (P=0.010) as well as shorter progression free survival and overall survival (P<0.0001). CD69 demonstrated true additive prognostic properties, since the CD69(+) plus ZAP-70(+) or CD38(+) or immunoglobulin variable heavy chain gene unmutated patients had the worst progression free survival and overall survival (P<0.0001). Interestingly, low CD69 expression was necessary to correctly prognosticate the longer progression free survival of patients with a low tumor burden of ß(2)-microglobulin (P=0.002), of soluble CD23 (P=0.020), or of Rai stages 0-I (P=0.005). CD69 was confirmed to be an independent prognostic factor in multivariate analysis of progression free survival (P=0.017) and overall survival (P=0.039). CONCLUSIONS: Our data indicate that CD69 is significantly correlated with poor clinical and biological prognostic factors and is confirmed to be an independent disease prognosticator. This supports its introduction in a routine laboratory assessment and, possibly, in a prognostic scoring system for chronic lymphocytic leukemia, after an adequate standardization process.

13q14 deletion size and number of deleted cells both influence prognosis in chronic lymphocytic leukemia.

Deletion at 13q14 is detected by fluorescence in situ hybridization (FISH) in about 50% of chronic lymphocytic leukemia (CLL). Although CLL with 13q deletion as the sole cytogenetic abnormality (del13q-only) usually have good prognosis, more aggressive clinical courses are documented for del13q-only CLL carrying higher percentages of 13q deleted nuclei. Moreover, deletion at 13q of different sizes have been described, whose prognostic significance is still unknown. In a multi-institutional cohort of 342 del13q-only cases and in a consecutive unselected cohort of 265 CLL, we investigated the prognostic significance of 13q deletion, using the 13q FISH probes locus-specific identifier (LSI)-D13S319 and LSI-RB1 that detect the DLEU2/MIR15A/MIR16-1 and RB1 loci, respectively. Results indicated that both percentage of deleted nuclei and presence of larger deletions involving the RB1 locus cooperated to refine the prognosis of del13q-only cases. In particular, CLL carrying <70% of 13q deleted nuclei with deletions not comprising the RB1 locus were characterized by particularly long time-to-treatment. Conversely, CLL with 13q deletion in <70% of nuclei but involving the RB1 locus, or CLL carrying 13q deletion in ≥70% of nuclei, with or without RB1 deletions, collectively experienced shorter time-to-treatment. A revised flowchart for the prognostic FISH assessment of del13q-only CLL, implying the usage of both 13q probes, is proposed.