Dario Ferrero

Significant Correlation Between the Degree of WT1 Expression and the International Prognostic Scoring System Score in Patients With Myelodysplastic Syndromes

PURPOSE To determine whether pattern of WT1 gene expression is a useful marker for establishing prognosis and tracking disease progression in patients with myelodysplastic syndromes (MDS). PATIENTS AND METHODS We performed a quantitative assessment of the WT1 transcript amount by real-time quantitative polymerase chain reaction (RQ-PCR) in 173 samples (131 bone marrow samples and 42 peripheral-blood samples) from 131 patients with MDS (79 patients with refractory anemia [RA], 31 with RA with excess blasts [RAEB], 18 with secondary acute myeloid leukemia [s-AML] evolved from MDS, and three with deletion of 5q as the sole cytogenetic abnormality). Values obtained were correlated with the blast percentage and International Prognostic Scoring System (IPSS) score. RESULTS Sixty-five percent of BM and 78% of PB samples for RA and 100% of BM and PB samples of RAEB and s-AML expressed WT1 transcript amounts greater than the level observed in healthy volunteers. The degree of WT1 expression was highly correlated with the type of MDS, was much higher in RAEB and s-AML compared with RA, and increased during disease progression. Moreover, a significant correlation was found between WT1 expression levels, blast cell percentage, and the presence of cytogenetic abnormalities. Therefore, we found a significant correlation between the amount of WT1 transcripts and the IPSS score, which currently represents the most reliable risk index of disease progression available for MDS patients. CONCLUSION WT1 is a useful molecular marker for risk assessment in MDS patients.

Azacitidine for the treatment of patients with acute myeloid leukemia: report of 82 patients enrolled in an Italian Compassionate Program.

The efficacy of azacitidine for the treatment of high‐risk myelodysplastic syndromes has prompted the issue of its potential role even in the treatment of acute myeloid leukemia (AML).

Induction of differentiation in human HL-60 cells by 4-hydroxynonenal, a product of lipid peroxidation☆

4-Hydroxynonenal (HNE) is the major diffusible toxic product generated by lipid peroxidation of cellular membranes. The level of lipid peroxidation and, consequently, the concentration of its products are inversely related to the rate of cell proliferation and directly related to the level of cell differentiation. In the present paper the effects of HNE on the proliferation and differentiation of the HL-60 human promyelocytic cell line have been investigated. Repeated treatment at 45-min intervals with HNE (1 microM) was performed to maintain the cells in the presence of the aldehyde for 7 1/2 or 9 h. The effect of HNE on cell proliferation and differentiation was compared with dimethyl sulfoxide (DMSO)-treated cells. HNE causes a strong inhibition of cell growth without affecting cell viability. Moreover, HL-60 cells acquire the capability to produce chemiluminescence after soluble (phorbol myristate acetate) or corpuscolate (zymosan) stimulation. The phagocytic ability has also been calculated by counting the number of cells that phagocytize opsonized zymosan. Values were 43 and 55% after 10 or 12 HNE treatments, respectively, and 88% in DMSO-treated cells. Myeloperoxidase activity, 5 days after treatment, decreased by 85% in either HNE- or DMSO-treated cells while acid phosphatase activity increased with respect to untreated cells. Results obtained indicate that HNE at concentrations close to those found in the normal tissues can induce inhibition of proliferation and induction of differentiation in the HL-60 cell line.

Peripheral blood expansion of early progenitor cells after high-dose cyclophosphamide and rhGM-CSF

In 20 patients with non-Hodgkin lymphoma or breast cancer, high-dose cyclophosphamide induced, during the post-nadir period of rapid leucocyte recovery, on median day 19 about a 30-fold increase in the peak concentration of granulocyte-macrophage (CFU-GM) and erythroid (BFU-E) colony-forming cells, and an even higher increase in the more immature pluripotent progenitors (CFU-Mix, 72-fold). After infusion of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF), peak concentration was reached earlier (median day 15) and with further enhancements (159, 116 and 283-fold respectively, in the number of CFU-GM, BFU-E and CFU-Mix). Most CFU-GM were immature, lacking the differentiation antigen CD15, and gave rise to large myeloid colonies, reflecting a high proliferative capacity of the founder cells. Very immature maphosphamide-resistant progenitors were detectable. The marked expansion in the circulating pool was predictable and reliable, allowing harvesting, after two or three leukaphereses, of sufficient haematopoietic progenitors for autologous bone-marrow reconstitution.

A validated real-time quantitative PCR approach shows a correlation between tumor burden and successful ex vivo purging in follicular lymphoma patients.

OBJECTIVE Purging procedures are increasingly used to provide stem cell collections devoid of contaminating tumor cells. In follicle center lymphoma (FCL), most approaches eradicate polymerase chain reaction (PCR);-detectable disease in only a fraction of harvests undergoing ex vivo manipulation. In this study we evaluated whether there is a relationship between tumor burden of stem cell harvests and successful clearance of PCR-detectable disease following ex vivo manipulation. MATERIALS AND METHODS To address this issue, we developed a real-time PCR approach for quantitative measurement of tumor contamination using the bcl-2 rearrangement. Real-time PCR was used to evaluate the relationship between tumor burden of stem-cell harvests and purging effectiveness in PCR(+) samples derived from 10 FCL patients. Ex vivo purging was performed using the MaxSep cell separator (Baxter Immunotherapy, Deerfield, IL, USA). RESULTS Our real-time PCR method proved effective, sensitive, accurate, and reproducible. Four collections were successfully cleared of minimal residual disease (MRD) whereas six remained PCR(+). Real-time PCR showed that the four collections successfully cleared of MRD had a prepurging tumor burden significantly lower than those remaining PCR(+) (p = 0.04). CONCLUSION This study provides the first evidence that evaluation of tumor burden in stem-cell harvests by real-time PCR can predict the effectiveness of therapeutic intervention in non-Hodgkins lymphoma. Based on these findings, we foresee a more widespread use of this technique to evaluate the impact of different therapeutic approaches in FCL.

Inhibition of Cell Survival and Invasive Potential of Colorectal Carcinoma Cells by the Tyrosine Kinase Inhibitor STI571

Inhibiting tyrosine kinases has recently emerged as a therapeutic modality in several forms of neoplasia. The tyrosine kinase inhibitor STI571 (IMATINIB MESYLATE; GLEEVEC; GLIVEC) is a case in point as it has shown promise in the treatment of malignancies expressing the BCR/ABL fusion protein. In addition to BCR/ABL, STI571 inhibits the tyrosine kinase moieties of several cell surface receptors including the platelet-derived growth factor (PDGF) receptors and c-Kit. Previous work demonstrated that c-Kit activation supports migration, invasion and, survival of certain colorectal carcinoma cells including DLD-1. Here we describe that blocking c-Kit with STI571 inhibits these malignant traits not only in DLD-1 cells but also in two early passage colorectal carcinoma cell strains. Specifically, STI571 inhibited anchorage-independent colony formation and cell scattering in semi-solid medium. Furthermore, it enhanced apoptosis susceptibility and abrogated invasion of DLD-1 cells through Matrigel. In addition, STI571 treatment affected the balance of the Bcl-2 family of apoptosis regulators on favor of a pro-apoptotic phenotype. Specifically, STI571 treatment of DLD1 cells was associated with lower levels of Bcl-2 expression accompanied by de novo expression of Bcl-xS. Finally, STI571 acted as a chemosensitizing agent in DLD-1 cells when used in combination with 5-fluorouracil.

Negative immunomagnetic ex vivo purging combined with high-dose chemotherapy with peripheral blood progenitor cell autograft in follicular lymphoma patients: evidence for long-term clinical and molecular remissions.

The feasibility and efficacy of a novel immunomagnetic ex vivo negative purging method was evaluated on peripheral blood progenitor cells (PBPC) from 13 non-Hodgkin’s lymphoma patients (eight follicular, FL; three mantle cell, MCL; two FL with histologic transformation). A peculiar feature of the study was the collection of PBPC after prolonged tumor debulking. Our method included a stem cell enrichment phase followed by cell incubation with anti-B cell MoAbs (anti-CD19, CD20, CD22, CD23), addition of immunobeads, and then positive cell removal by passage on a Max-Sep (Baxter Immunotherapy) cell separator. Engraftment was rapid and stable. Hematological values were assessed 1 and 2 years after the autograft. Purging efficacy was molecularly assessed in a panel of 11 patients who showed persistence of PCR-detectable lymphoma cells on PBPC harvests despite intensified chemotherapeutic debulking. PCR-negativity was obtained in vitro and persisted in vivo after autograft in three FL patients; five more FL patients, whose purged PBPC were PCR+, converted to stable (3 patients) or fluctuating (two patients) PCR negativity after autograft. MCL patients never reached PCR negativity. Thus, ex vivo purging may have a role for FL patients harvesting PCR-positive PBPC after intensified chemotherapy. In contrast, the addition of ex vivopurging seems to be of little if any benefit for MCL patients.

Incidence, risk factors and management of pleural effusions during dasatinib treatment in unselected elderly patients with chronic myelogenous leukaemia

To assess the most important features and clinical impact of pleural effusions, which are a common toxicity during dasatinib treatment and often impair its high efficacy, 172 unselected consecutive patients with chronic myelogenous leukaemia in chronic phase treated in 27 Italian centres, with dasatinib when aged >60 years for resistance/intolerance to imatinib, were examined. During treatment, 52/172 patients (30.2%) presented pleural effusion, which was grades 1–2 in 38 patients and grades 3–4 in 14 patients (8.1% of the entire cohort of patients), according to the WHO scale; in 14/52 patients (26.9%), there was a concomitant pericardial effusion. Pleural effusion was recurrent in 25/52 patients (48.0%). Median time from dasatinib to first pleural effusion was 11.0 months (interquartile range 3.6–18.6). Eleven patients (6.4%) required permanent dasatinib discontinuation. Only presence of concomitant pulmonary disease ( p = 0.035) and initial daily dose of dasatinib (140 mg vs 100 mg, p = 0.014) were significantly associated with pleural effusions. There were no differences among patients with or without pleural effusions as concerns response rates and overall survival. Pleural effusions were common in our unselected ‘real‐life’ population of elderly patients but were clinically manageable and did not seem to affect treatment results. Copyright

Combined differentiating therapy for myelodysplastic syndromes : A phase II study

An in vitro synergism between different inducers of AML cell differentiation has been previously observed. Therefore, we treated 53 myelodysplastic (MDS) patients with a low dose combination of cis-retinoic acid (cRA, 20-40 mg/day) and 1,25 alpha (OH)2 cholecalciferol [(OH)2D3, 1-1.5 micrograms/day] +/- intermittent 6-thioguanine (30 mg/m2/day). The latter was reserved for patients with bone marrow (BM) blast excess (> or = 5%). The treatment was well tolerated, without major toxicity. Among 25 patients with BM blasts less than 5%, we observed one complete, eight partial and four minor responses (response rate 52%) with a median response duration of 8 months (2 +/- 24). Median survival, which did not correlate with response, is projected at 76 months. Thirty-one patients with BM blast excess (> or = 5%), including three of the previous group who progressed to refractory anemia with excess of blasts (RAEB), were treated with the three-drug protocol. One complete, 12 partial and six minor responses were obtained (response rate 61%) with a median response duration of 6 months (2-29+). A significant difference in survival (P < 0.005) was observed between the 19 responders (median 25 months) and the 12 non-responders (median 9 months). A reduction in the transfusion need was observed in 41% of the transfusion-dependent patients with blast excess and in 53% of those without blast excess. Therefore, combined differentiating therapy seems more effective than previously reported single agent treatments and should be considered for a larger randomized study to assess its actual impact on survival of MDS patients.

Can the revised IPSS predict response to erythropoietic-stimulating agents in patients with classical IPSS low or intermediate-1 MDS?

To the editor: The “classical” International Prognostic Scoring System (IPSS), based on cytogenetics, marrow blast percentage, and number of cytopenias, has played a major role in prognosis assessment in myelodysplastic syndromes (MDS).[1][1] The recently published revised IPSS (IPSS-R), using