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1.
Clin Exp Rheumatol ; 31(1 Suppl 75): S9-14, 2013.
Article in English | MEDLINE | ID: mdl-23044040

ABSTRACT

OBJECTIVES: To study the health-related quality of life (HRQOL) in severe cryoglobulinaemic vasculitis (CV) associated with hepatitis C virus infection (HCV) and to describe the effect of rituximab on HRQOL. METHODS: HRQOL was evaluated with the Medical Outcomes Study Short Form 36 (SF-36). Health Survey questionnaire was submitted to 15 patients with severe CV. SF-36 questionnaire was evaluated at baseline and after rituximab. Physical Health Composite Summary (PCS) and Mental Health Composite Summary (MCS) scores were calculated according to standard protocols, and normalised to healthy controls. SF-36 summary scores were compared with those of HCV positive patients without CV, and other vasculitis published in the literature. European Quality of Life-5 dimensions (EQ5D) scores were also derived. RESULTS: Physical and mental domain scores were all reduced if compared with those of the healthy population, with physical domains being greatly affected. HRQOL of CV was comparable with HRQOL reported for the other small vessel vasculitis. The development of CV in HCV positive patients worsened PCS rather than MCS score. Birmingham Vasculitis Activity Score (BVAS) did not correlate with HRQOL, while the presence of peripheral neuropathy was associated with a worse HRQOL. Early rituximab treatment improved both PCS and MCS scores, with long-term effects. CONCLUSIONS: PCS rather than MCS was affected in HCV positive patients when CV is present. Rituximab improved both physical and mental domains, thus supporting its use before antiviral therapy in severe HCV-related CV. The cost/benefits ratio of a sequential therapy may be supported.


Subject(s)
Antibodies, Monoclonal, Murine-Derived/therapeutic use , B-Lymphocytes/drug effects , Cryoglobulinemia/drug therapy , Health Status , Immunologic Factors/therapeutic use , Lymphocyte Depletion/methods , Quality of Life , Vasculitis/drug therapy , Adult , Aged , Antibodies, Monoclonal, Murine-Derived/economics , B-Lymphocytes/immunology , Cost-Benefit Analysis , Cryoglobulinemia/blood , Cryoglobulinemia/economics , Cryoglobulinemia/immunology , Cryoglobulinemia/physiopathology , Cryoglobulinemia/psychology , Drug Costs , Female , Hepatitis C/complications , Hepatitis C/immunology , Hepatitis C/virology , Humans , Immunologic Factors/economics , Lymphocyte Depletion/economics , Male , Mental Health , Middle Aged , Quality-Adjusted Life Years , Rituximab , Severity of Illness Index , Surveys and Questionnaires , Time Factors , Treatment Outcome , Vasculitis/blood , Vasculitis/economics , Vasculitis/immunology , Vasculitis/physiopathology , Vasculitis/psychology
2.
Arthritis Rheum ; 64(3): 843-53, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22147661

ABSTRACT

OBJECTIVE: To conduct a long-term, prospective, randomized controlled trial evaluating rituximab (RTX) therapy for severe mixed cryoglobulinemia or cryoglobulinemic vasculitis (CV). METHODS: Fifty-nine patients with CV and related skin ulcers, active glomerulonephritis, or refractory peripheral neuropathy were enrolled. In CV patients who also had hepatitis C virus (HCV) infection, treatment of the HCV infection with antiviral agents had previously failed or was not indicated. Patients were randomized to the non-RTX group (to receive conventional treatment, consisting of 1 of the following 3: glucocorticoids; azathioprine or cyclophosphamide; or plasmapheresis) or the RTX group (to receive 2 infusions of 1 gm each, with a lowering of the glucocorticoid dosage when possible, and with a second course of RTX at relapse). Patients in the non-RTX group who did not respond to treatment could be switched to the RTX group. Study duration was 24 months. RESULTS: Survival of treatment at 12 months (i.e., the proportion of patients who continued taking their initial therapy), the primary end point, was statistically higher in the RTX group (64.3% versus 3.5% [P < 0.0001]), as well as at 3 months (92.9% versus 13.8% [P < 0.0001]), 6 months (71.4% versus 3.5% [P < 0.0001]), and 24 months (60.7% versus 3.5% [P < 0.0001]). The Birmingham Vasculitis Activity Score decreased only after treatment with RTX (from a mean ± SD of 11.9 ± 5.4 at baseline to 7.1 ± 5.7 at month 2; P < 0.001) up to month 24 (4.4 ± 4.6; P < 0.0001). RTX appeared to be superior therapy for all 3 target organ manifestations, and it was as effective as conventional therapy. The median duration of response to RTX was 18 months. Overall, RTX treatment was well tolerated. CONCLUSION: RTX monotherapy represents a very good option for severe CV and can be maintained over the long term in most patients.


Subject(s)
Antibodies, Monoclonal, Murine-Derived/therapeutic use , Cryoglobulinemia/therapy , Immunologic Factors/therapeutic use , Adolescent , Adult , Aged , Aged, 80 and over , Antiviral Agents/therapeutic use , Azathioprine/therapeutic use , Combined Modality Therapy , Cryoglobulinemia/complications , Cryoglobulinemia/pathology , Cyclophosphamide/therapeutic use , Drug Resistance, Viral/drug effects , Drug Substitution , Drug Therapy, Combination , Female , Glucocorticoids/therapeutic use , Hepatitis C, Chronic/complications , Hepatitis C, Chronic/drug therapy , Humans , Male , Middle Aged , Plasmapheresis , Remission Induction , Rituximab , Severity of Illness Index , Treatment Outcome , Young Adult
4.
Ann Oncol ; 14(3): 475-80, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12598356

ABSTRACT

BACKGROUND: Large-scale CD34+ enrichment has been demonstrated a safe method in autologous transplantation for multiple myeloma. However, the high CD34+ enrichment and the consequent plasma cell purging result in concomitant T-cell and dendritic-cell (DC) depletion, theoretically increasing the risk of life-threatening infections. PATIENTS AND METHODS: We evaluated immunological and dendritic reconstitution in 72 myeloma patients who had undergone CD34+-selected (n = 45) and unmanipulated (n = 27) stem cell transplant, and its correlation with infections. RESULTS: Haematological recovery occurred promptly in all patients. Only a slight delay in platelet recovery to >50 x 10(9)/l was observed in patients receiving CD34+-enriched graft. Natural killer (NK) cell count recovered in all patients within 2 months and B-cell count had recovered by 6 months post-transplant in both groups. CD3 cells remained lower than normal in both groups. CD8 cells increased above the normal level, reaching a peak at day 90, and lowered to normal level within 1 year post-transplant. CD4 lymphocytes remained <50% of normal, especially in selected patients. In both groups, both DC1 and DC2 counts were already significantly lower than in normal individuals before conditioning therapy. Pre-conditioning levels of DC1 were reached in unmanipulated patients at day 30 and became normal at 6 months. In selected patients, DC1 pre-transplant level was observed at day 60 and was maintained thereafter. DC2 recovery showed a similar trend. In unselected patients, DC2 count increased to pre-conditioning level at haematological recovery and was normal after 1 year. In selected transplants, DC2 increased more slowly than DC1 in the same patients: pre-transplant level was detected at day 90 but was still significantly lower than normal 1 year after transplant. The incidence of infection was similar in both groups. Sepsis had Gram+ aetiology in the majority of cases. After engraftment only viral infections were recorded, mostly due to herpes reactivation, with no difference between groups. DISCUSSION: In spite of a delay in immune recovery, CD34 enrichment is not associated with a significant increase of complications due to infection. Relatively fast NK cell recovery to pre-transplant levels and the presence of functionally efficient DCs can justify the low incidence of infections.


Subject(s)
Antigens, CD34/immunology , Dendritic Cells/immunology , Infections/etiology , Multiple Myeloma/immunology , Multiple Myeloma/therapy , Peripheral Blood Stem Cell Transplantation , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Female , Granulocyte Colony-Stimulating Factor/administration & dosage , Humans , Immunomagnetic Separation , Infections/immunology , Killer Cells, Natural/physiology , Male , Middle Aged , Peripheral Blood Stem Cell Transplantation/adverse effects , Risk Factors , T-Lymphocytes/immunology
5.
Bone Marrow Transplant ; 30(5): 261-6, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12209346

ABSTRACT

There is persistent immunosuppression not only in allogeneic but also in autologous stem cell transplantation because humoral and cellular immunity may take a year or more to return to normal, with increased risk of infectious complications. This immune defect may also involve antigen presentation, in particular dendritic cell (DC) function. We evaluated DC subset reconstitution in 58 patients who underwent bone marrow (BM) or peripheral blood (PB) autologous haematopoietic stem cell transplantation (HSCT). In all patients DC type 1 (DC1) and DC type 2 (DC2) were already significantly lower than in normal individuals before conditioning therapy (DC1/microl 3.1 +/- 1.0, DC2/microl 3.0 +/- 1.1). On day 0 and day +7 the mean DC1 and DC2 numbers were very low in both groups. Patients who received unmanipulated marrow or peripheral blood stem cells reached pre-conditioning levels of DC1 and DC2 cells on day +20. In patients receiving selected CD34 cells, DC increased slowly and pre-transplant counts were observed only on day +60. Nearly 'normal' levels of DC1 and DC2 could be observed in the first group from day +180, and were maintained thereafter; in CD34(+) selected patients DC1 and DC2 counts remained lower than normal. Our data emphasise that circulating antigen presenting cells (APC) recover quickly. It remains to be determined if DC frequency in PB reflects their tissue function. The relatively low incidence of infections in patients undergoing autologous transplantation, despite defective lymphocyte reconstitution, could be related to functionally efficient DC.


Subject(s)
Dendritic Cells/cytology , Hematopoietic Stem Cell Transplantation , Hematopoietic Stem Cell Transplantation/standards , Adolescent , Adult , Antigens, CD34 , Blood Cells , Bone Marrow Transplantation/methods , Bone Marrow Transplantation/standards , Cell Count , Dendritic Cells/classification , Female , Graft Survival , Hematologic Neoplasms/therapy , Hematopoietic Stem Cell Transplantation/methods , Humans , Immune System/cytology , Kinetics , Lymphocytes/cytology , Lymphocytes/immunology , Male , Middle Aged , Peripheral Blood Stem Cell Transplantation/methods , Peripheral Blood Stem Cell Transplantation/standards , Transplantation, Autologous/methods , Transplantation, Autologous/standards
6.
Leuk Lymphoma ; 42(4): 721-9, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11697502

ABSTRACT

In this work three human cell lines with multidrug resistance (MDR) caused by a P-glycoprotein (PGP) overexpression, CEM VLB, HL60 DNR, LOVO DX and two cell lines with MDR associated with a multidrug related protein (MRP) or a lung resistance-related protein (LRP) overexpression named GLC4 ADR and SW1573/2R120 were tested for Amifostine protection against Daunorubicin, Doxorubicin, Idarubicin and Mitoxantrone toxicity. This class of anticancer agents was chosen because they are commonly used in the first line treatments of acute leukemias where a PGP, an LRP or an MRP overexpression often occurs even at onset. A 7-day incubation with escalating doses of anticancer agents with or without a 15 minute preincubation in Amifostine or its active metabolite WR-1065 were used. In conclusion, in none of the MDR positive and negative cell lines did Amifostine modify the toxicity of the anticancer drugs. The observation that even the WR-1065 metabolite gave no protection against Anthracyclines toxicity strengthened the data and provided confirmation for the further in vivo testing of the safety and efficacy of Amifostine in leukemias.


Subject(s)
Amifostine/pharmacology , Antibiotics, Antineoplastic/pharmacology , Antineoplastic Agents/toxicity , Cytoprotection , Mitoxantrone/toxicity , ATP-Binding Cassette Transporters , Cell Division/drug effects , Dose-Response Relationship, Drug , Drug Interactions , Drug Resistance, Multiple , Humans , Mercaptoethylamines/pharmacology , Radiation-Protective Agents/pharmacology , Tumor Cells, Cultured
7.
Br J Haematol ; 108(4): 703-9, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10792272

ABSTRACT

We analysed the expression of three drug transporter proteins [p-glycoprotein (PGP), lung resistance-related protein (LRP) and multidrug resistance-associated protein (MRP1)] involved in anthracycline resistance that are frequently overexpressed in poor-risk adult acute non-lymphocytic leukaemia (ANLL), in 23 acute promyelocytic leukaemia (APL) patients at onset managed at a single institution. Cellular daunorubicin accumulation was also evaluated. At onset, no case had PGP or MRP1 expression that exceeded that of non-multidrug-resistant (MDR) cell lines. Only one case showed LRP overexpression. No peculiar MDR features distinguished the seven patients who relapsed from those who maintained complete remission. In the onset vs. first relapse, only one patient showed an increased (threefold) PGP expression at relapse. At second relapse, three out of four patients showed a PGP expression two- to threefold higher than baseline values. These results are consistent with the view that low PGP, LRP and MRP1 expression and the absence of defects in intracellular drug accumulation may account for the peculiarly high sensitivity of APLs to anthracycline. It does not support the screening of MDR markers in APL patients at onset as predicting factors of early relapse. The results suggest that no significant changes in PGP, LRP or MRP1 expression are likely to occur at first relapse. In contrast, PGP expression is likely to increase later in the patient history as a result of additional chemotherapy courses.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , ATP-Binding Cassette Transporters/metabolism , Antibiotics, Antineoplastic/pharmacology , Drug Resistance, Multiple , Leukemia, Promyelocytic, Acute/metabolism , Neoplasm Proteins/metabolism , Vault Ribonucleoprotein Particles/metabolism , Adolescent , Adult , Aged , Daunorubicin/metabolism , Female , Humans , Male , Middle Aged , Multidrug Resistance-Associated Proteins , Recurrence , Tumor Cells, Cultured/metabolism
9.
Br J Haematol ; 106(1): 92-9, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10444168

ABSTRACT

The possibility that Daunoxome (DNX), a combination of daunorubicin (DNR) with a liposomal targeting system, escapes PGP was tested. Two pairs of leukaemic cell lines, each consisting of the parental non-multidrug resistance (MDR) line and of a MDR variant, were studied for cytotoxicity (MTT test) and for cellular DNR kinetic and accumulation (flow cytometry). DNX and free DNR were equally toxic against non-MDR cells, whereas the liposomal anthracycline was more toxic than the free drug against the MDR variant. Non-MDR cells accumulated DNR more rapidly when they were exposed to free DNR than to DNX, but MDR cells accumulated more DNR when they were exposed to DNX. The kinetics of DNX and free DNR were also studied in the blast cells of 41 cases of acute leukaemia and they were found to be related to blast cell PGP expression. In 15 cases with a low PGP expression intracellular DNR accumulation was faster and higher with free DNR than with DNX. In 26 cases with a high PGP expression the area under the curve was similar with DNX and free DNR, but the kinetics of intracellular DNR accumulation showed an early low plateau with free DNR and a slow and continuous increase with DNX. In MDR cell lines the ratio was more favourable to DNX than to free DNR. We conclude that liposome encapsulated DNR is partially protected from PGP and that it is worth testing for the treatment of PGP-positive acute leukaemia.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1 , Daunorubicin/administration & dosage , Leukemia/drug therapy , Acute Disease , Daunorubicin/pharmacokinetics , Drug Carriers , Drug Resistance, Multiple , Drug Resistance, Neoplasm , Drug Screening Assays, Antitumor , HL-60 Cells , Humans , Leukemia/metabolism , Liposomes , Tumor Cells, Cultured
11.
Br J Haematol ; 104(2): 328-35, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10050716

ABSTRACT

P-glycoprotein (PGP), lung resistance-related protein (LRP) and multidrug resistance associated protein (MRP) expression and the blast cells' intracellular daunorubicin accumulation (IDA) were evaluated in 96 previously untreated cases of de novo acute non-lymphocytic leukaemia (ANLL). 47/96 patients (49%) were classified as PGP+ 44/ 96 (46%) as LRP+, and 8/96 (8%) as MRP+. The more frequent MDR clusters were PGP-/LRP-/MRP- (32/96 cases, 33%) and the PGP+/LRP+/MRP- (27/96 cases, 28%) followed by PGP+/LRP-/MRP- (15/96 cases, 16%) and PGP-/LRP+/MRP- (14/96 cases, 14%). A favourable karyotype was observed more frequently in PGP- and LRP-cases. A highly significant correlation was found between either PGP or LRP overexpression and leukaemic blast cell IDA. All the patients received standard induction and consolidation treatments containing MDR-related (idarubicin, mitoxantrone, etoposide) and other (arabinosyl cytosine) drugs. Multivariate analysis showed that PGP overexpression was significantly associated with a poor response to treatment, both in terms of primary resistance or shorter survival. Other independent prognostic factors were age and cytogenetics. LRP overexpression did not reach statistical significance, although for LRP+ cases the trend was unfavourable. Due to small numbers, no conclusion could be made regarding MRP overexpression, but 5/8 cases showed unfavourable karyotypic abnormalities, 8/8 had a defective IDA and 6/8 failed to achieve remission. This study showed that both PGP and LRP overexpression are common features in de novo ANLL at onset whereas MRP overexpression is more rare. It suggested that overexpression of one of the MDR related proteins was associated with a defective IDA, and confirmed that, in addition to age and cytogenetics, PGP retains an independent prognostic value. It also suggested that LRP did not affect clinical outcome when patients were treated with idarubicin or mitoxantrone and arabinosyl cytosine.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Genes, MDR , Leukemia, Myeloid, Acute/metabolism , Neoplasm Proteins/metabolism , Vault Ribonucleoprotein Particles/metabolism , Acute Disease , Adolescent , Adult , Aged , Aged, 80 and over , Antineoplastic Agents/therapeutic use , Chromosome Aberrations , Female , Humans , Karyotyping , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/genetics , Male , Middle Aged , Prognosis , Survival Rate
12.
Haematologica ; 83(4): 290-7, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9592977

ABSTRACT

BACKGROUND AND OBJECTIVE: In cell lines, there is an ongoing debate about the role of the lung resistance-related protein (LRP) whereas the role played by P-glycoprotein (PGP) in determining a multidrug resistance is well known. The aim of this study was to evaluate the frequency and the role of a PGP and an LRP overexpression in affecting the intracellular daunorubicin accumulation (IDA) and in predicting the therapy outcome on a subset of overt secondary acute non lymphocytic leukemias (ANLL). An adjunctive point was to evaluate the efficacy of the reversal agent SDZ PSC 833 (PSC) in counteracting impaired IDA. DESIGN AND METHODS: By flow cytometry, PGP and LRP expression and the IDA were evaluated on 54 overt secondary ANLL PGP and LRP overexpressions were respectively defined by an MRK-16 mean fluorescence index (MFI) > or = 6 (PGP+) and by an LRP-56 MFI > or = 5 i.e. by MRK-16 and LRP-56 MFIs higher than the one observed in normal leukocytes. The blasts' IDA was studied after a two-hour incubation in 1000 ng/mL daunorubicin in the presence or in the absence of the MDR reversal agent SDZ PSC 833 (PSC) 1.6 mumol. RESULTS: A PGP overexpression was detected in 40/54 (74%) cases while an LRP overexpression was observed on 33/54 (61%) cases. No differences were found in terms of PGP and LRP expressions between ANLL developing after chemo/radiotherapy (therapy-related ANLL) or evolving from a myelodysplastic syndrome (MDS-related ANLL). Compared to the PGP-, the PGP+ cases showed a significantly lower mean IDA (DNR NMFI 196 +/- 46 vs. 267 +/- 53, p < 0.001). The co-incubation of DNR with the PSC significantly increased only the mean IDA of the PGP+ cases, that grew from a DNR NMFI of 196 +/- 46 to a DNR NMFI of 284 +/- 67 (p < 0.0001). With respect to normal leukocytes, even the PGP- cases had an impaired IDA suggesting that other mechanisms, including an LRP overexpression, could affect the IDA. A strongly negative correlation was observed between PGP overexpression and therapy outcome, in fact, 8/10 (80%) PGP- but only 2/27 (7%) PGP+ patients obtained complete remission (p = 0.0002). Moreover, 7/33 (21%) cases showing an impaired IDA (NMFI < 280) but 4/4 (100%) with NMFI > 280 had complete remission (p = 0.006). No correlation was found between therapy response and LRP or CD34 expression. INTERPRETATION AND CONCLUSIONS: This data suggests that an important role in determining therapy outcome is played by PGP in secondary leukemias. Even if the LRP is frequently overexpressed in secondary leukemias and is likely to contribute to the reduction of the intracellular drug accumulation, the role played by LRP in determining the therapy-outcome has still to be cleared.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/blood , Leukemia, Myeloid, Acute/diagnosis , Neoplasm Proteins/blood , Neoplasms, Second Primary/diagnosis , Vault Ribonucleoprotein Particles , ATP Binding Cassette Transporter, Subfamily B, Member 1/biosynthesis , Adult , Aged , Antigens, CD34/biosynthesis , Bone Marrow Cells/chemistry , Bone Marrow Cells/cytology , Bone Marrow Cells/metabolism , Cell Line/metabolism , Daunorubicin/analysis , Daunorubicin/therapeutic use , Humans , Intracellular Fluid/chemistry , Leukemia, Myeloid, Acute/drug therapy , Leukocytes/chemistry , Leukocytes/immunology , Leukocytes/metabolism , Middle Aged , Neoplasm Proteins/biosynthesis , Prognosis , Treatment Outcome
13.
Adv Clin Path ; 2(1): 59-64, 1998 Jan.
Article in English | MEDLINE | ID: mdl-10358333

ABSTRACT

The expression of the mdr-1 gene coding for a transmembrane 170 KD glycoprotein (P170 or PGP) is an important cause of multidrug resistance (MDR). In tumor cells the expression of the gene may vary and there is experimental evidence that it can be induced by exposure to MDR-unrelated agents. We investigated if the therapeutic exposure to Arabinosyl Cytosine (AC) could affect the level of P170 expression in the blast cells of acute non-lymphocytic leukemia (ANLL). The reactivity to the P170-directed MRK 16 monoclonal antibody of the marrow blast cells from 27 patients with ANLL prior and after treatment with standard dose AC was evaluated by flow cytometry. After treatment with AC the MRK 16 mean fluorescence index (MFI) was increased in 5/18 cases of primary and previously untreated ANLL and in 7/9 cases of relapsed or secondary leukemia. Overall, the mean value of the MFI was 6.8+/-3.6 before and 9.0+/-3.8 after AC (P=0.001, Wilkoxon matched pairs test). Therapeutic exposure to AC in vivo may increase P170 expression in leukemic cells. This may influence the definition and the quantitation of resistance and may have therapeutic implications, concerning the association with other cytotoxics and the use of MDR modifiers.

14.
Br J Haematol ; 96(2): 356-65, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9029025

ABSTRACT

P-glycoprotein (PGP) lung resistance protein (LRP) and multidrug resistance associated protein (MRP) expressions and function were evaluated by flow cytometry in 65 leukaemic patients (38 acute non-lymphocytic leukaemias, eight acute lymphocytic leukaemias, 19 Ph-positive chronic myeloid leukaemias in blastic phase). By using the MRK-16, the LRP-56 and the MRPm6 MoAbs, 34% of the cases did not over-express any proteins (-); 24.5% over-expressed (+) only PGP, 11% only LRP, 1.5% only MRP, 24.5% both PGP and LRP, and 4.5% both PGP and MRP. The mean intracellular daunorubicin accumulation (IDA) and rhodamine 123 (Rh123) retention in the presence or absence of the reversal agent SDZ PSC 833 (PSC) of the PGP-/LRP-/MRP- cases were comparable to the ones observed in normal leucocytes. With respect to the non-over-expressing cases, the PGP-/LRP+/MRP- cases showed only an impaired IDA (mean 204 +/- 29; P < 0.001). The PGP+/ LRP+/MRP- cases had a defect both in IDA (mean 166 +/- 47, P < 0.001) and Rh123 retention (mean 0.42 +/- 0.14: P < 0.001), which were both corrected by PSC. All the PGP+/LRP+/MRP- cases had a defect in IDA (mean daunorubicin (DNR) accumulation 192 +/- 44; P < 0.001). However, only in 8/16 of them an evident defect in Rh123 retention was found. In conclusion, both PGP and LRP over-expression were common in leukaemia. An impaired IDA was found in all cases over-expressing PGP, LRP or both. The study of Rh123 retention could give incorrect information about the blast cells' ability to accumulate cytotoxic drugs in patients over-expressing both PGP and LRP.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , ATP-Binding Cassette Transporters/metabolism , Daunorubicin/metabolism , Leukemia/metabolism , Neoplasm Proteins/metabolism , Rhodamines/metabolism , Vault Ribonucleoprotein Particles , Daunorubicin/therapeutic use , Drug Resistance, Multiple , Drug Resistance, Neoplasm , Humans , Leukemia/drug therapy , Lymphocytes/metabolism , Multidrug Resistance-Associated Proteins , Rhodamine 123 , Rhodamines/therapeutic use
15.
Leuk Lymphoma ; 23(1-2): 99-105, 1996 Sep.
Article in English | MEDLINE | ID: mdl-9021691

ABSTRACT

The biologic and clinical importance of the multidrug resistance (MDR) that is related with the overexpression of the P170 glycoprotein (Pgp) is widely recognized. However, a major issue that has not yet been solved is the definition of the degree of Pgp expression which is associated with a significant decrease of the sensitivity of the cells to chemotherapy. For this reason we studied the leukemic cells from 83 cases of acute leukemia. Leukemic cells were fixed in PLP and treated with saponine. Pgp expression was assayed by flow cytometry, using the anti Pgp monoclonal antibody MRK-16. Results were expressed both as the number of positive cells and by the intensity of the reaction as defined by the mean fluorescence index (MFI), i.e. the ratio between the mean fluorescence intensity of the MRK-16 incubated cells and of the IgG2a incubated cells. Thus, Pgp expression was compared with the results of two in vitro tests of cell sensitivity to anthracyclines, daunorubicin (DNR) cell retention and DNR cytotoxicity. We found that it was not the number of MRK-16 positive cells, but the degree of the reaction with MRK-16 (MFI) that significantly related to the anthracycline toxicity tests. Therefore, we propose that for clinical purposes a quick and cheap determination of Pgp-related MDR in leukemic cells may be obtained by measuring the MFI with MRK-16 in a standard flow cytometry assay and that the assay may indeed be sufficient to estimate Pgp expression as well as the influence of Pgp on cell sensitivity to anthracyclines.


Subject(s)
Anthracyclines/therapeutic use , Antineoplastic Agents/therapeutic use , Drug Resistance, Multiple , Leukemia/drug therapy , Anthracyclines/metabolism , Antibodies, Monoclonal , Antineoplastic Agents/metabolism , Cells, Cultured , Drug Screening Assays, Antitumor , Humans , Leukemia/metabolism , Leukocytes/drug effects , Leukocytes/metabolism , Tumor Cells, Cultured
16.
Haematologica ; 79(6): 500-7, 1994.
Article in English | MEDLINE | ID: mdl-7896208

ABSTRACT

BACKGROUND: Overexpression of the mdr-1 gene that codes for a 170 Kd transmembrane glycoprotein (P170) is a factor responsible for decreased cell sensitivity to anthracyclines and other drugs, and is related to treatment failure in acute leukemia and other tumors. Several agents, including verapamil and cyclosporine derivatives, can modify P170-related resistance in vitro and can be proposed as adjuvant treatment for leukemia and cancer. MATERIALS AND METHODS: To investigate the optimal conditions for adjuvant treatment, D-verapamil (D-VRP), cyclosporin-A (CyA) and the cyclosporine derivative SDZ PSC 833 (PSC) were used alone and in combination at drug concentrations that can be achieved and maintained in vivo. The drugs were tested for their capacity to restore intracellular daunorubicin (DNR) and idarubicin (IDA) accumulation in high-resistance (CEM VLB 300) and intermediate-resistance (CEM VLB 100) cells to levels found in the non-resistant parental cell line (CCRF CEM). RESULTS: In intermediate-resistance cells, IDA alone was more easily restored than DNR plus modifiers, and intracellular IDA concentration was returned to the level of non-resistant cells with low-dose D-VRP (1 microM), CyA (0.8 microM) and PSC (0.4 microM). In high-resistance cells no modifier or modifier combination was able to restore intracellular DNR concentration to the value of non-resistant cells. Intracellular IDA concentration was almost completely restored only with D-VRP (2-3 microM) and CyA (0.8-1.6 microM) in combination or with PSC alone (0.4 microM). CONCLUSIONS: These data suggest that as far as P170-related resistance is concerned, IDA alone is as efficient as or even more efficient than DNR plus modifiers, and that residual resistance to IDA can be overcome with a combination of D-VRP and Cy-A at a clinically achievable concentration, or with a more powerful modifier like SDZ PSC 833.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/physiology , Cyclosporine/pharmacology , Cyclosporins/pharmacology , Daunorubicin/metabolism , Idarubicin/metabolism , Leukemia-Lymphoma, Adult T-Cell/pathology , Neoplasm Proteins/physiology , Verapamil/pharmacology , Biological Transport/drug effects , Drug Resistance, Multiple , Humans , Tumor Cells, Cultured/drug effects
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