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G Mateo

Publications and source records attributed to G Mateo.

13 recordsLinked to original sources

Clonal plasma cells from monoclonal gammopathy of undetermined significance, multiple myeloma and plasma cell leukemia show different expression profiles of molecules involved in the interaction with the immunological bone marrow microenvironment.

The immunological bone marrow (BM) microenvironment plays a major role in controlling growth and survival of clonal plasma cells (PC); this might translate into different patterns of expression of molecules involved in immune responses on PC from different types of monoclonal gammopathies (MG). We have studied the expression of a group of nine such molecules on both BMPC and the plasma of 61 newly diagnosed MG patients (30 MG of undetermined significance (MGUS), 27 multiple myeloma (MM) and four plasma cell leukemia (PCL)) and five normal individuals. Clonal PC from all MG displayed significantly increased levels of CD56, CD86 and CD126, and decreased amounts of CD38 (P<0.001). Additionally, HLA-I and beta2-microglobulin were abnormally highly expressed in MGUS, while CD40 expression was decreased in MM and PCL (P<0.05). Interestingly, a progressive increase in the soluble levels of beta2-microglobulin was found from MGUS to MM and PCL patients (P=0.03). In contrast, all groups showed similar surface and soluble amounts of CD126, CD130 and CD95, except for increased soluble levels of CD95 observed in PCL. Overall, those phenotypic differences are consistent with increased antigen presentation and costimulatory capacities in MGUS, which progressively deteriorate in malignant MG (MM and PCL).

Aged↗

Proliferative activity of plasma cells is the most relevant prognostic factor in elderly multiple myeloma patients.

Although multiple myeloma (MM) is predominantly a disease of the elderly, few studies have focused on the identification of prognostic factors in this group of patients. Four hundred twenty five MM patients >65 years were uniformly treated with chemotherapy (MP or VCMP/VBAD). Multivariate analysis identified 4 factors with independent unfavorable prognostic influence: high percentage of S-phase bone marrow plasma cells (>2.5%); elevated beta(2) microglobulin (B2M) (>4 mg/L); age >80 years old; and LDH serum levels (above normal limit). The S-phase value was the most powerful independent prognostic factor to discriminate subgroups of patients with different prognosis. Thus, 3 main risk categories could be identified according to S-phase values: </=1%, 1-3% and >3%, with median survivals of 34, 22 and 12 months, respectively (p < 0.0001). Our study also proved the value for elderly patients of the recently developed International Score System (ISS) based on B2M and albumin. Furthermore, the number of S-phase cells helped to subdivide the ISS III Group identifying a subset of patients with very poor prognosis defined by an additional high S-phase, who displayed a median survival of only 8 months. These results demonstrate that elderly patients can be accurately classified according to prognosis, which may be particularly valuable when comparing the efficacy of new treatment strategies. Moreover, our results underline the high prognostic value of proliferative activity of PC, a parameter that should be considered in routine laboratory investigations of MM.

Age Factors↗

Randomized comparison of dexamethasone combined with melphalan versus melphalan with prednisone in the treatment of elderly patients with multiple myeloma.

Melphalan-prednisone (MP) has been the gold standard treatment for more than 30 years in elderly multiple myeloma (MM) patients. In order to assess whether the combination of dexamethasone with melphalan (MD) could improve on the efficacy of MP, we have carried out a randomized trial comparing both treatment approaches. A total of 201 patients >/=70 years old were included in the study. The overall response rate was similar after six cycles (MP: 67.9%versus MD: 64.5%) and after 12 cycles (MP: 49.4%versus MD: 46.1%). However, the proportion of complete responses (CR) was higher in the MD arm, particularly after 12 cycles (MD: 22.4%versus MP: 9.1%; P < 0.05). There was no significant difference in event-free survival (MP: 15.9 months versus MD: 23.3 months). The median overall survival in both arms was almost identical (MP: 29.4 months versus MD: 27.2 months; P = 0.63). No significant differences in haematological toxicity were observed, but non-haematological toxicity was significantly higher in the MD arm. According to these results MP remains as the gold standard for treatment of MM and should be the reference for comparison of new therapeutic approaches involving novel agents.

Aged↗

Immunophenotypic analysis of Waldenstrom's macroglobulinemia.

Immunophenotyping has become an essential tool for diagnosis of hematological malignancies. By contrast, for diagnosis of Waldenstrom's macroglobulinemia (WM) immunophenotyping is used only occasionally. From 150 patients with a IgM monoclonal gammopathy we have selected 60 cases with (1) morphological lymphoplasmocytoid bone marrow (BM) infiltration (>20%); (2) IgM paraprotein (>10g/L); and (3) absence of features of other lymphoma types. Immunophenotypic analysis was based on the use of the triple or quadruple monoclonal antibody (MoAb) combinations. To increase the sensitivity of the analysis of antigen expression, selected CD19(+)CD20(+) B cells were targeted. We have also explored the antigenic characteristics of both the plasma cell (PC) and mast cell (MC) compartments present in the BM from 15 WM patients. Clonal WM lymphocytes were characterized by the constant expression of pan-B markers (CD19, CD20, CD22, CD24) together with sIg, predominantly kappa (5:1, kappa:lambda ratio). A high proportion of cases (75%) were positive for FMC7 and CD25, but in contrast to hairy cell leukemia (HCL), these lymphocytes were always negative for CD103 and CD11c. CD10 antigen was also absent in all WM patients and less than one fifth of patients were positive for CD5 and CD23, while CD27, CD45RA, and BCL-2 were present in most malignant cells. In two cases, the coexistence of two different clones of B lymphocytes was identified, and in eight additional cases, intraclonal phenotypic heterogeneity was observed. As far as PCs are concerned, in most patients (85%) the number of PCs was within the normal range (median, 0.36%). The antigenic profile of these PCs differed from that observed in normal and myelomatous PC (CD38(++)CD19(++/-)CD56(-)CD45(++)CD20(+)). In three cases, PCs showed aberrant expression for CD5, CD22, or FMC7. Finally, the number of mast cells was significantly higher (0.058 +/- 0.13) as compared to normal BM (0.019 +/- 0.02) (P <.01), although they were immunophenotypically normal (CD117(+)CD2(-)CD25(-)).

Bone Marrow Cells↗

Adult precursor B-ALL with BCR/ABL gene rearrangements displays a unique immunophenotype based on the pattern of CD10, CD34, CD13 and CD38 expresssion.

The Philadelphia chromosome (Ph+) reflects a balanced reciprocal translocation between the long arms of chromosomes 9 and 22 [t(9;22)(q34;q11.2] involving the BCR and ABL genes. At present, detection of BCR/ABL gene rearrangements is mandatory in precursor-B-ALL patients at diagnosis for prognostic stratification and treatment decision. In spite of the clinical impact, no screening method, displaying a high sensitive and specificity, is available for the identification of BCR/ABL+ precursor-B-ALL cases. The aim of the present study was to explore the immunophenotypic characteristics of precursor B-ALL cases displaying BCR/ABL gene rearrangements using multiple stainings analyzed by quantitative flow cytometry in order to rapidly (<1 h) identify unique phenotypes associated with this translocation. From the 82 precursor-B-ALL cases included in the study 12 displayed BCR/ABL gene rearragements, all corresponding to adult patients, four of which also displayed DNA aneuploidy. Our results show that BCR/ABL+ precursor B-ALL cases constantly displayed a homogeneous expression of CD10 and CD34 but low and relatively heterogeneous CD38 expression, together with an aberrant reactivity for CD13. In contrast, this unique phenotype was only detected in three out of 70 BCR/ABL cases. Therefore, the combined use of staining patterns for CD34, CD38 and CD13 expression within CD10-positive blast cells is highly suggestive of BCR/ABL gene rearrangements in adults with precursor B-ALL.

Adult↗

The detection of contaminating clonal cells in apheresis products is related to response and outcome in multiple myeloma undergoing autologous peripheral blood stem cell transplantation.

In the present paper, we report on the use of the heteroduplex PCR technique to detect the presence of clonally rearranged VDJ segments of the heavy chain immunoglobulin gene (VDJH) in the apheresis products of patients with multiple myeloma (MM) undergoing autologous peripheral blood stem cell (APBSC) transplantation. Twenty-three out of 31 MM patients undergoing APBSC transplantation with VDJH segments clonally rearranged detected at diagnosis were included in the study. Samples of the apheresis products were PCR amplified using JH and VH (FRIII and FRII) consensus primers and subsequently analyzed with the heteroduplex technique, and compared with those obtained at diagnosis. 52% of cases yielded positive results (presence of clonally rearranged VDJH segments in at least one apheresis). The presence of positive results in the apheresis products was not related to any pretransplant characteristics with the exception of response status at transplant. Thus, while no one patient with positive apheresis products was in complete remission (CR), negative immunofixation, before the transplant, five cases (46%) with negative apheresis were already in CR at transplant (P = 0.01). The remaining six cases with heteroduplex PCR negative apheresis were in partial remission before transplant. Patients with clonally free products were more likely to obtain CR following transplant (64% vs 17%, P= 0.02) and a longer progression-free survival, (40 months in patients transplanted with polyclonal products vs 20 with monoclonal ones, P = 0.03). These results were consistent when the overall survival was considered, since it was better in those patients with negative apheresis than it was in those with positive (83% vs 36% at 5 years from diagnosis, P= 0.01). These findings indicate that the presence of clonality rearranged VDJH segments is related to the response and outcome in MM transplanted patients.

Hematopoietic Stem Cell Transplantation↗

Correlation between cytogenetic abnormalities and disease characteristics in multiple myeloma: monosomy of chromosome 13 and structural abnormalities of 11q are associated with a high percentage of S-phase plasma cells.

BACKGROUND AND OBJECTIVES: Cytogenetic studies in multiple myleoma (MM) are limited by the difficulties in obtaining metaphases that can be investigated and few studies have analyzed the relationship between cytogenetics and clinical disease characteristics. The aim of our study was to analyze the recurrent cytogenetic changes in MM and to correlate them with clinical and biological characteristics including the percentage of S-phase plasma cells (PCs). DESIGN AND METHODS: Chromosomal abnormalities were analyzed in 86 patients with MM. In all patients, two types of cultures (5 d culture with interleukin-4 and unstimulated 72 h culture) were used for cytogenetic analysis. DNA content analysis (ploidy and cell cycle analysis) together with the most relevant clinical and biological disease features were studied. RESULTS: Cytogenetic analysis was successful in 72 of the 86 patients (84%). Forty-seven patients (65%) had an abnormal karyotype. The most frequent trisomies involved chromosomes 3, 5, 9, 11, 15, 19, 22, 1, 7, 17, 18, and 21, and monosomies affected chromosomes 13 and 8, while structural changes involved chromosomes 1, 11, 14q32, 4p16 and 16q22-23. Patients with abnormal karyotype displayed a poor performance status, advanced stage, anemia and a high percentage of bone marrow plasma cells. In addition, MM patients with -13/13q- and 11q abnormalities showed a significantly higher proportion of S-phase PCs (p=0.02). INTERPRETATION AND CONCLUSIONS: In summary, our study shows a relationship between unfavorable cytogenetics (-13/13q-/11q abnormalities) and a high percentage of S-phase PCs, a well-known adverse prognostic factor.

Aged↗

High-sensitive immunophenotyping and DNA ploidy studies for the investigation of minimal residual disease in multiple myeloma.

Sensitive techniques for monitoring minimal residual disease (MRD) in multiple myeloma (MM) are needed to evaluate the effectiveness of new intensive treatment strategies. The aim of the present study was to explore the applicability and sensitivity of flow cytometry immunophenotyping and DNA ploidy studies for the investigation of residual myelomatous plasma cells (PC) in MM patients. Bone marrow (BM) samples from 61 untreated MM patients were immunophenotypically analysed with a panel of 21 monoclonal antibodies, using a high-sensitive method based on a two-step acquisition procedure through a SSC/CD38 -CD138+ 'live-gate'. Overall, in 87% of MM cases, PC displayed an aberrant phenotype at diagnosis. The most important aberrant criteria were: antigen over-expression of CD56 (62%), CD28 (16%) and CD33 (6%) and asynchronous expression of CD117 (28%), sIg (21%) and CD20 (10%). DNA aneuploidy was found in 62% of cases. The simultaneous use of these two techniques allowed the detection of aberrant/aneuploid PC in 95% of the cases. Based on dilutional experiments, the detection limit of both techniques ranged from 10(-4) to 10(-5). In 29 stem cells harvests and 19 BM samples obtained 3 months after autologous transplantation, we have investigated the presence of residual myelomatous PC; they were detected in 44% of the stem cell collections and in 61% of the BM samples obtained after transplant. The percentage of pathological PC did not significantly change during the days of harvest. In summary, the present study shows that the combined use of immunophenotyping and DNA ploidy studies is a suitable approach for MRD investigation in MM patients based on their applicability (95% of cases) and sensitivity (up to 10(-5)).

Bone Marrow Transplantation↗

Immunophenotypic and DNA content characteristics of plasma cells in multiple myeloma and monoclonal gammopathy of undetermined significance.

In the present paper we review the immunophenotypic characteristics of plasma cells (PC) and the PC DNA contents from multiple myeloma (MM) and monoclonal gammopathy of undetermined significance (MGUS), and its value for the differential diagnosis between both entities. The strong reactivity for CD38 and the positivity for CD138 are the two best markers for identifying PC. Myelomatous PC display an heterogeneous phenotype consistent with the fact that the neoplastic clone is able to undergo a certain degree of differentiation. In addition, PC from MM patients usually lack surface expression of B-cell associated antigens and frequently display reactivity for markers which are not restricted to the B-cell lineage. In MGUS patients, two clearly defined and distinct PC subpopulations can be identified. One of these PC subpopulations shows phenotypic characteristics identical to those of normal PC, including a very strong reactivity for the CD38 antigen, intermediate/low light scatter characteristics and positivity for CD19, in the absence of CD56, and corresponds to the residual normal bone marrow PC. The second PC subpopulation shows an immunophenotype similar to that of myelomatous PC, characterized by a slightly lower reactivity for CD38 and strong CD56 expression, on the absence of positivity for CD19, these PC corresponding to the clonal counterpart. Using a simultaneous staining for PC and DNA, around 60% of MM and 73% of MGUS patients display DNA aneuploidy, the majority of them being hyperdiploid. However, in contrast to MM patients, in MGUS patients two clearly different PC subsets can be discriminated in most cases (73%): a diploid and an aneuploid (hyperdiploid) subset, corresponding to normal and clonal PC, respectively. Upon comparing hyperdiploid with diploid patients in MM, the former display a better prognosis, in line with the higher incidence of DNA hyperdiploidy in MGUS. A clear correlation between the percentage of S-phase PC and several prognosis features of MM has been found. In spite of these findings, no significant differences in the percentage of pathological S-phase PC are detected between MM and MGUS patients. Regarding the differential diagnosis between MGUS and MM, multivariate analysis shows that the ratio between the number of clonal and normal residual PC is the best single parameter.

Antigens, Neoplasm↗

IL-4 improves the detection of cytogenetic abnormalities in multiple myeloma and increases the proportion of clonally abnormal metaphases.

In the present study the incidence of abnormal karyotypes and the number and proportion of abnormal metaphases obtained in multiple myeloma (MM) using three culture conditions were compared: unstimulated culture (72 h), IL-6/GM-CSF-stimulated culture (120 h) and IL-4-stimulated culture (120 h). The three types of culture conditions were assessed simultaneously on bone marrow samples from 30 consecutive myeloma patients. In addition DNA content (DNA ploidy and cell cycle) was analysed by flow cytometry. The number of MM samples with clonal karyotypic abnormalities was higher after IL-4-stimulated cultures (53%) than it was after IL-6 + GM-CSF (37%) and unstimulated (30%) cultures. The benefit of IL-4 was also observed in cases with low numbers of plasma cells in the bone marrow, in early clinical stages and in untreated patients. In those cases in whom clonal chromosomal abnormalities were detected by the three culture methods. the cytogenetic findings were always identical. According to our results the addition of IL-4 to the cultures of bone marrow cells in MM increases the number of abnormal metaphases.

Aged↗