[show abstract][hide abstract] ABSTRACT: p53 status and CD38 antigen are biological factors influencing response to therapy and clinical course in B-cell chronic lymphocytic leukemia (B-CLL). This study tests the hypothesis that soluble p53 alone and in association with CD38 can enucleate B-CLL subsets at worse prognosis.
Wild and mutant forms of p53 protein were evaluated in 197 B-CLL patients at diagnosis or before progression by an immunoenzymatic method in plasma using an anti-p53 monoclonal antibody. CD38 expression was analyzed by a multicolor flow cytometric assay.
Higher levels of both soluble p53 (sp53) and CD38 were significantly correlated with intermediate and high Rai stages, with higher beta2-microglobulin and soluble CD23 values, determined at diagnosis. Shorter overall survival (OS) and progression-free survival (PFS) were both observed in sp53+ and CD38+ patients (p<0.0001). Simultaneous positivity or negativity for sp53 and CD38 identified two subsets of patients, the former with a worse prognosis and the latter with a better prognosis with regard to PFS (p<0.0001) and OS (p<0.0001). The predictive value of sp53 and CD38 was retained among the patients within the intermediate Rai risk group.
sp53 and CD38 together with ZAP-70 were confirmed to be independent prognostic factors in multivariate analysis. With regard to PFS, ZAP-70, sp53 and CD38 were confirmed to be independent prognostic factors. Concerning OS, ZAP-70, CD38 and age (< or > 60 years) were independent prognostic factors whereas sp53 showed only a tendency towards statistical significance.
[show abstract][hide abstract] ABSTRACT: Structural abnormality of the 11q23 band (11q23+) bearing the MLL gene translocation (MLL+) is a recurrent chromosome change observed in 3% to 7% of acute lymphoblastic leukemias and in 3% to 4% of acute myeloblastic leukemias. The resolution of conventional cytogenetics (CC) in detecting 11q23 rearrangement is limited when the translocative partner has a telomeric location; furthermore, CC can barely discriminate between true 11q23+/MLL+ and rearrangements clustering within the 11q22 to approximately 25 region without MLL involvement (MLL-). We characterized a series of 378 consecutive patients with adult acute leukemia by using CC, fluorescence in situ hybridization (FISH), and multiplex karyotyping (M-FISH) analysis. Our aim was to define the frequency of cryptic MLL+ cases and the frequency of MLL+ within 11q22 to approximately 25+ cases. As expected, FISH was more sensitive than CC in detecting MLL+ cases, but rather unexpectedly, 9 (45%) of 20 patients with 11q22 to approximately 25+ were MLL-. A better characterization of 11q22 to approximately 25+/MLL- leukemias is relevant for the identification of new, recurrent translocations. Moreover, these cases should be readily distinguishable from 11q23+/MLL+ cases. We recommend that karyotypic analysis always be complemented by molecular or FISH methods to unravel MLL rearrangements.
American Journal of Clinical Pathology 09/2004; 122(2):298-306. · 2.88 Impact Factor
[show abstract][hide abstract] ABSTRACT: Different transformation mechanisms have been proposed for elderly acute myeloid leukaemia (AML) and secondary AML (sAML) when compared with de novo AML or AML of younger patients. However, little is known regarding differences in the immunophenotypic profile of blast cells in these diseases. We systematically analysed, by flow cytometry, 148 patients affected by de novo (100 cases) or sAML (48 cases). By defining a cut-off level of 20% of CD34+ cells co-expressing CD90, the frequency of CD90+ cases was higher in sAML (40%) versus de novo AML (6%, P < 0.001), elderly AML (>60 years) (24%) versus AML of younger patients (10%, P = 0.010) and poor- versus good-risk karyotypes (according to the Medical Research Council classification, P < 0.001). The correlation between CD90 expression, sAML and unfavourable karyotypes was confirmed by analysing the subset of CD34+ AML cases alone (91/148). Consistently, univariate analysis showed that expression of CD90 was statistically relevant in predicting a shorter survival in CD90+ AML patients (P = 0.042). Our results, demonstrating CD90 expression in AML with unfavourable clinical and biological features, suggest an origin of these diseases from a CD90-expressing haemopoietic progenitor and indicate the use of CD90 as an additional marker of prognostic value in AML.
British Journal of Haematology 04/2004; 125(2):203-12. · 4.94 Impact Factor
[show abstract][hide abstract] ABSTRACT: Concurrent resistance mechanisms, such as P-glycoprotein (PGP) and bcl-2, may contribute to a worse outcome in adult acute lymphoblastic leukaemia (ALL). Between 1990 and 2000, we analysed PGP and bcl-2 by flow cytometry, using two anti-PGP (C219 and JSB-1) monoclonal antibodies (mAbs) and an anti-bcl-2 mAb in 115 de novo adult ALL patients. Both a longer overall survival (OS) and longer disease-free survival (DFS) were observed in PGP-negative patients (23%vs 0% at 3 years, P = 0.011 and 29%vs 0% at 2 years, P = 0.006 for C219 respectively; 42%vs 0% at 1.5 years, P = 0.004 and 53%vs 0% at 8.5 months, P = 0.00006 for JSB-1 respectively). Bcl-2 positivity was associated with a significantly higher complete remission rate (90%vs 66%, P = 0.01). Moreover, in 69 patients not presenting with either t(9;22) or B-mature immunophenotype, PGP negativity (JSB-1) maintained its significant favourable prognostic impact with regard to OS (41%vs 0% at 1.5 years, P = 0.009) and DFS (83%vs 0% at 6 months, P = 0.0005). Importantly, within a subset of 62 patients with normal (n = 31) or unknown (n = 31) karyotype, PGP (JSB-1)-negative patients showed both a significantly longer OS and DFS (63%vs 0% at 1.4 years, P = 0.018 and 84%vs 0% at 6 months, P = 0.001 respectively). In multivariate analysis, JSB-1 (P = 0.008) and cytogenetics (P = 0.02) were found to be independent prognostic factors with regard to DFS. Therefore, in adult ALL, PGP and bcl-2 represent sensitive indicators of clinical outcome, and potential targets of novel molecules aimed at overcoming chemoresistance and recurrent relapses.
British Journal of Haematology 07/2003; 121(5):730-8. · 4.94 Impact Factor
[show abstract][hide abstract] ABSTRACT: The inability to undergo apoptosis is a crucial mechanism of multidrug resistance in acute myeloid leukemia (AML), and the analysis of mitochondrial apoptotic proteins may represent a significant prognostic tool to predict outcome. Bcl-2 and Bax oncoproteins were evaluated in 255 de novo AML patients (pts) by flow cytometry using an anti-bcl-2 monoclonal antibody (MoAb) and an anti-bax MoAb. The results were expressed as an index (bax/bcl-2) obtained by dividing bax mean fluorescence intensity (MFI) and bcl-2 MFI. Lower bax/bcl-2 ratio was associated with French-American-British (FAB) M0-M1 classes (P =.000 01) and CD34 more than 20% (P <.000 01). There were striking inverse correlations between CD34 or CD117 MFI and bax/bcl-2 values (r = -.40, P <.000 001 and r = -.29, P =.000 002), confirming that immaturity is consistent with this index. Moreover, lower bax/bcl-2 levels were correlated with poor-risk cytogenetics (P =.0002). A significant higher complete remission (CR) rate was found in pts with higher bax/bcl-2 levels (79% versus 45%; P =.000 01). Also, both a longer overall survival (OS) and disease-free survival (DFS) were observed in pts with higher bax/bcl-2 levels (P =.000 01 and =.019). Noteworthy, bax/bcl-2 levels accurately predicted the clinical response and outcome of pts with normal or unknown cytogenetics. Indeed, within this subset of 147 pts, higher bax/bcl-2 ratio was significantly associated both with a higher CR rate (86% versus 42%; P <.000 01) and a longer OS (P =.0016). The independent prognostic value of bax/bcl-2 ratio was confirmed in multivariate analysis. Therefore, mitochondrial oncoproteins, such as bcl-2 and bax, represent both sensitive indicators of clinical outcome and potential targets of novel proapoptotic molecules in order to circumvent chemoresistance.
[show abstract][hide abstract] ABSTRACT: Fluorescence in situ hybridization (FISH) is becoming popular in the diagnosis of clonal chromosomal abnormalities. We set up a fast FISH procedure using an extensive set of specific probes. Conventional banding analysis (CBA) and FISH were compared in 260 newly diagnosed acute myeloid leukemia (AML) patients. For FISH the following probes were used: MLL, CBF-beta/MYH11, ETV-6/AML1; AML1/ETO, BCR/ABL, PML/RAR, c-MYC, TP53, RB1, 5q31/5p15.2, 5q33-34, 7q31/CEP7, 20q13; CEP 4, X, Y. Result time was 96 h for CBA versus 5 h for FISH from direct harvest. CBA showed clonal abnormalities in 41% (n=105/260), normal karyotype in 39% (n=102/260) and failed in 20% (n=53/260). FISH screened all patients and detected abnormalities in 39% (n=102/260); CBA and FISH together identified abnormalities in 49% (n=128/260). In six patients with normal CBA and in eight patients with clonal karyotype, it detected further cryptic abnormalities. CBA showed clonal abnormalities in 13% of patients negative at FISH (n=21/158). FISH screening does not add relevant information to CBA, but is the quickest method for detecting major genetic abnormalities in AML. The speed of FISH is very valuable in AML-M3/M3v because PML/RAR+ patients require specific therapy. Furthermore, we suggest FISH screening in failed, complex or suboptimal quality chromosome and specific FISH analysis for 5q, 7q, 12p, 17p, inv(16), t(11q23) in order to implement CBA accuracy.
The Hematology Journal 02/2003; 4(4):263-70. · 1.86 Impact Factor