Ernesto Vigna

Clonal heterogeneity in chronic lymphocytic leukemia cells: superior response to surface IgM cross-linking in CD38, ZAP-70-positive cells

The reasons why immunoglobulin gene mutation status and expression of ZAP-70 and CD38 influence disease progression in chronic lymphocytic leukemia are still undefined. This study shows that CD38+, ZAP-70+ cells have a greater capacity for signalling through the B-cell receptor and suggests a function for B-cell receptor signaling in promoting cell expansion. Background Patients with chronic lymphocytic leukemia whose cells express CD38 and ZAP-70 and utilize unmutated Ig VH region genes have a very poor prognosis. We studied whether cells expressing CD38 and ZAP-70 are more susceptible to stimulation through B-cell receptors than are cells that do not express CD38 and ZAP-70. Design and Methods CD38-positive and CD38-negative leukemic cells were separated from single cases and compared for their response to B-cell receptor cross-linking and ZAP-70 expression. Cohort studies were also carried out by measuring the apoptotic response to surface immunoglobulin M (IgM) cross-linking in 82 patients with chronic lymphocytic leukemia and the protein tyrosine phosphorylation induced by surface IgM in 21 patients. Results CD38-positive cells, isolated from cases of chronic lymphocytic leukemia classified as CD38-positive or CD38-negative, expressed more ZAP-70 than the corresponding CD38-negative cells, exhibited more robust protein tyrosine phosphorylation and had a greater tendency to apoptosis upon B-cell receptor cross-linking. In the cohort studies, surface IgM-induced protein tyrosine phosphorylation correlated significantly with CD38 and ZAP-70 expression and with the absence of Ig VH gene mutations. Apoptosis induced by surface IgM cross-linking correlated significantly only with the proportion of CD38-positive cells. Difficulties in finding more definitive correlations were probably related to imprecision in the in vitro test system and in the definition of cases as positive or negative. Conclusions Collectively, these data indicate that CD38-positive, ZAP-70-positive cells have a greater capacity for signaling through the B-cell receptor and suggest a function for B-cell receptor signaling in promoting chronic lymphocytic leukemia cell expansion, especially within the CD38-positive fraction of the leukemic clone.

The cumulative amount of serum free light chain is a strong prognosticator in chronic lymphocytic leukemia

Identification of patients at risk of early disease progression is the mainstay of tailored management in chronic lymphocytic leukemia (CLL). Although application of established biomarkers is limited by intrinsic detection/readout complexities, abnormality of κ and λ serum-free light chain ratio [sFLC (κ/λ)] was proposed as a straightforward prognosticator in CLL. By analyzing 449 therapy-naive patients, we show that an abnormal sFLC(κ/λ), along with CD38, ZAP-70, IGHV mutations, cytogenetics and stage, independently predicts treatment-free survival (TFS) but becomes prognostically irrelevant if the cumulative amount of clonal and nonclonal FLCs [sFLC(κ + λ)], a variable associated with cytogenetic risk, exceeds the threshold of 60.6 mg/mL. Patients with sFLC(κ + λ) above cut-off displayed a poorer TFS outcome, irrespective of sFLC(κ/λ). Only ZAP-70, cytogenetics, stage, and TFS remained associated with sFLC(κ + λ) in a multivariate model. By assigning 1 point each for these variables, the 3-year probability of TFS was 94.8%, 84.5%, 61.6%, and 21.1% for patients scoring 0, 1, 2, and 3 + 4, respectively (P < .0001). These data, and the demonstration that monoclonal and polyclonal B cells concur to FLC synthesis in tumor tissues, suggest that sFLC(κ/λ) and sFLC(κ + λ) mirror distinct biologic processes in CLL. sFLC(κ + λ) assessment represents a sensitive and cost-effective tool for identifying CLL patients requiring early treatment.

Anti-leukemic and anti-GVHD effects of campath-1H in acute lymphoblastic leukemia relapsed after stem-cell transplantation

Despite aggressive approaches, including second transplant, donor lymphocyte infusion and several new agents, the prognosis of acute lymphoid leukemia (ALL) patients relapsing after stem-cell transplantation (SCT) remains poor. Monoclonal-antibodies (moAb) could provide a useful tool in this setting. In particular, anti-CD52 moAb is useful in lymphoid malignancies. We thus treated as compassionate with campath-1H 3 ALL patients relapsed after SCT. In 2 cases we observed a reduction of peripheral blood and/or bone marrow blasts. In 1 case a GVHD grade reduction was observed. Larger trials are required in order to define the role of campath-1H in ALL.

Therapeutic approaches for newly diagnosed multiple myeloma patients in the era of novel drugs.

The treatment of newly diagnosed multiple myeloma (MM) has evolved rapidly over recent years. The availability of new effective drugs with novel mechanisms of action, such as thalidomide, lenalidomide and bortezomib in the last decade, has resulted in a new scenario expected to impact favorably on the outcome of patients with MM. The introduction of new drugs in the treatment of patients eligible for autologous stem cell transplantation (ASCT) has allowed for a significant increase of complete response rate with a positive impact on progression‐free survival. In patients not eligible for ASCT, randomized trials have shown that both thalidomide and bortezomib when combined with melphalan and prednisone (MP) are superior to MP and are now considered the standard of care. Ongoing trials are assessing whether MP plus lenalidomide or the combination of lenalidomide plus dexamethasone should be considered an attractive treatment option, while additional studies are needed to determine the role of routine maintenance or consolidation therapy with these new drugs. This new therapeutic armamentarium in light of adequate prophylaxis and supportive care allows clinicians to greatly improve the survival perspectives for both young and elderly patients. In this review, we report updated data for the front‐line therapy of MM, examining the role of new drugs either when administered as induction therapy before ASCT in younger patients or when combined with alkylating agents for the treatment of older patients. The most relevant articles on therapy of MM published from November 1982 to January 2010 (selected through PubMed), and recent meeting abstracts were used as sources for this review.

Validation of the CLL-IPI and comparison with the MDACC prognostic index in newly diagnosed patients

To the editor: Recently, an international collaboration collected information from ∼3500 chronic lymphocytic leukemia (CLL) patients to develop a comprehensive tool for predicting overall survival (OS) (the international prognostic index for patients with chronic lymphocytic leukemia [CLL-IPI]).[

Perspectives in the treatment of multiple myeloma.

Introduction: The development of proteasome inhibitor (PI) and immunomodulatory drugs (IMiDs) and advances in supportive care have considerably changed the treatment paradigm of multiple myeloma (MM) and significantly improved survival. Nevertheless, almost all patients show disease relapse and develop drug resistance. Areas covered: We review the prognostic stratification and therapeutic strategy for newly diagnosed MM patients. Furthermore, mechanisms of drug resistance are discussed. Data regarding newer drugs, currently undergoing examination, such as PI (carfilzomib, ONX0912, MLN9708, and marizomib), IMiDs (pomalidomide), histone deacetylase inhibitors (vorinostat and panobinostat), kinase inhibitors (temsirolimus, everolimus, and tanespimycin), and immune-based therapies (elotuzumab, siltuximab, MOR03087, and MMBT062) are reported. Expert opinion: The use of three to four drug combination therapies including PI and IMiDs has significantly impacted on MM patient outcome. Moreover, new insights into MM biology from high-throughput technologies and availability of newer and more efficacious drugs will continue to influence our approach to MM treatment. In the immediate future molecular subgroup-specific trials using targeted agents may represent a very important step toward evaluating impact of interfering with relevant signaling pathways in MM. With the continued rapid evolution of progress in this field, MM will become a chronic illness having sustained complete response in a significant number of patients.

Epigenetic regulation in myelodysplastic syndromes: implications for therapy

Introduction: Myelodysplastic syndromes (MDS), characterized by ineffective hematopoiesis and dysplasia in one or more lineages, produce life-threatening cytopenias and progress to acute myeloid leukemia (AML). Growing evidence suggests that targeting epigenetic mechanisms improves MDS/AML pathophysiology. Areas covered: This review provides an understanding of studies investigating novel agents published up to January 2011 aimed at normalizing and monitoring the epigenetic profile of the MDS cancer cell. The authors discuss how non-intensive epigenetic therapy can ‘re-programme’ gene expression patterns of abnormal hematopoiesis in MDS. Recently FDA-approved DNA-methyltransferase inhibitors, 5-azacytidine and 5-aza-2′-deoxycytidine or decitabine, represent frontline nonablative treatments, while combinations with histone deacetylase inhibitors show promising synergism in preclinical and Phase I/II trials in tumor suppressor gene re-expression and overall survival. Additional epigenetic mechanisms including non-encoding transcripts with inhibitory posttranscriptional regulatory functions, such as microRNAs, though not fully understood, present novel molecular and clinical implications in these disorders. Expert opinion: Alongside current single-agent epigenetic regimens, combination therapies represent potentially effective options for intermediate-2 and high-risk MDS. Methylation profiles and gene mutation predictors provide promising areas of development for monitoring MDS disease progression and outcome, while targeting microRNA dysregulation represents an important therapeutic goal.

Janus kinase 2 inhibitors in myeloproliferative disorders.

Importance of the field: JAK2 is an obligatory kinase for the proliferation and differentiation of erythroid cells and megakaryocytes thus representing a relevant therapeutic target for agents that specifically inhibit its activity particularly in myeloproliferative disorders (MPD) harboring JAK2V617F mutations. Areas covered in this review: We discuss the physiopathology of the JAK2 signaling pathway and review clinical trials of JAK2 inhibitors for the treatment of MPD using papers and meeting abstracts published up to September 2010. What the reader will gain: This review helps in understanding the potential role of JAK2 inhibitors in MPD clinical trials and provides a comprehensive review regarding their efficacy and safety in these disorders. Take home message: JAK2 inhibitors may prove to be useful only for suppressing disease manifestations. However, unlike drugs such as IFN which are capable of eliminating the malignant clone, JAK2 inhibitors are unable to eradicate the disease. In fact, results to date indicate that although these inhibitors reduce splenomegaly and alleviate constitutional symptoms irrespective of JAK2 mutational status, most have only a modest impact on the JAK2V617F allele burden. Considering the relevant risk of serious complications in patients undergoing splenectomy, these drugs could find a suitable indication in patients with myelofibrosis awaiting bone marrow transplantation.

Ixazomib for the treatment of multiple myeloma

Introduction: Proteasome inhibition is a mainstay in the treatment of multiple myeloma (MM). Bortezomib, the first proteasome inhibitor (PI) approved for MM therapy, has shown efficacy in relapsed/refractory patients and in the front-line setting. Among second-generation PIs, MLN9708 (ixazomib) is the first oral compound to be evaluated in MM treatment and has shown improvement in pharmacokinetic and pharmacodynamic parameters compared with bortezomib with a similar efficacy in the control of myeloma growth and in the prevention of bone loss. Areas covered: In this review, the authors discuss the rationale for use of PIs. They then summarize the clinical development of ixazomib in MM, from initial Phase I to Phase II studies as a monotherapy and in combination with other chemotherapeutics. Expert opinion: Preliminary data of Phase I/II trials showed that ixazomib had a good safety profile and exerted anti-myeloma activity as a single agent in relapsed/refractory patients. Furthermore, ixazomib also had efficacy in patients who were refractory to bortezomib. Its use in combination with lenalidomide and dexamethasone was shown to be an effective and well-tolerated regimen in up-front treatment leading to minimal residual disease negativity in a significant number of patients. Results of Phase III trials, evaluating ixazomib in induction or maintenance therapy, are awaited.

Italian external and multicentric validation of the MD Anderson Cancer Center nomogram and prognostic index for chronic lymphocytic leukaemia patients: Analysis of 1502 cases

We performed an external and multicentric validation of the nomogram and prognostic index (PI) proposed by the MD Anderson Cancer Center to prognostically stratify chronic lymphocytic leukaemia (CLL) patients in 1502 CLL cases. All six parameters involved in the nomogram and PI (age, sex, absolute lymphocyte count, number of lymph node groups, Rai stage and β2‐microglobulin) were independently associated with survival. The nomogram was accurate in predicting survival (c‐index = 0·82). According to the PI, 38·7% of patients were at low‐risk, 58·3% at intermediate‐risk and 3% at high‐risk. The estimated median survival times were: not reached for low‐risk, 13·4 years for intermediate‐risk and 3·4 years for high‐risk. The estimated median and 5‐year survival by PI were similar to those originally reported. The PI remained a predictor of survival when analysis was limited to 847 Rai stage 0 (P < 0·0001) and 151 clinical monoclonal B‐cell lymphocytosis (cMBL) cases (P = 0·033). Finally, the PI allowed prediction of time to therapy in all patients (P < 0·0001), in Rai 0 (P < 0·0001) and in cMBL cases (P = 0·044). Our results confirm the ability of the PI to predict prognosis, even in early stage disease cases. The study also extended the utility of the PI to cMBL cases.