Efficacy and safety of high-dose intravenous iron as the first-choice therapy in outpatients with severe iron deficiency anemia.

Background: Asymptomatic severe iron deficiency anemia is a common finding in subjects admitted to the outpatient anemia clinic. Although the condition can be easily be reversed with intravenous iron (IVI) therapy and several guidelines have suggested a restrictive threshold for using transfusion in hemodynamically stable patients, transfusion is often the rule in clinical practice. This study describes clinical practice results of IVI therapy without transfusion.

Ferric carboxymaltose reduces the number of red blood cell units transfused and allows transfusion independence to be obtained in patients with iron deficiency anemia secondary to gastrointestinal chronic blood loss.

Background: The aim of this study was to evaluate the effectiveness of ferric carboxymaltose (FCM) in patients with iron deficiency anemia (IDA) secondary to gastrointestinal chronic blood loss (CBL), who received chronic transfusion support.

Study Design And Methods: We retrospectively evaluated 38 patients with IDA (hemoglobin [Hb] < 10 g/dL and ferritin < 12 ng/mL or transferrin saturation [TSAT] < 16%) refractory or intolerant to oral iron therapy that necessitated transfusion support in the previous 12 months. They were treated with FCM (500-2500 mg).

Effect of fludarabine and arabinosylcytosine on multidrug resistant cells.

Background And Objective: Anthracyclines are first-line drugs in the treatment of acute leukemia, but the sensitivity of leukemic cells to anthracyclines can be downmodulated by multidrug resistance (MDR) transport proteins like Pgp. Pgp overexpression is negatively related to treatment response. Alternative drugs may be required to overcome the MDR problem.

Overcoming PGP-related multidrug resistance. The cyclosporine derivative SDZ PSC 833 can abolish the resistance to methoxy-morpholynil-doxorubicin.

Background: The results obtained so far in studies designed to neutralize P glycoprotein (PGP)-related multidrug resistance (MDR) by using MDR reversal agents, have not yet fulfilled the promise of the experiments which were performed in vitro. In order to improve PGP-related MDR neutralization, we tested in vitro the activity of the cyclosporine derivative SDZ PSC 833 (PSC) together with doxorubicin (DOX) and with two new DOX derivatives named 4' iodo 4' deoxy-doxorubicin (IODODOX) and methoxy-morpholynil-doxorubicin (MMDOX, FCE 23762) using four different human cell lines and their multi-drug resistant variants.

Methods: Anthracycline toxicity was evaluated by using the MTT method after a 7-day culture with continuous exposure to the antitumor drugs with or without the addition of PSC.

Plasma cell P170 expression and response to treatment in multiple myeloma.

Background: Vincristine and anthracyclines are first-line agents for the treatment of multiple myeloma (MM). P170-related multidrug resistance (MDR) may influence the response to these drugs.

Materials And Methods: P170 expression of bone marrow plasma cells was assayed by immunocytochemistry (alkaline phosphatase anti-alkaline phosphatase technique) with the MRK-16 monoclonal antibody.

MDR-related P170-glycoprotein modulates cytotoxic activity of homoharringtonine.

Homoharringtonine (HHT) is a new drug with antileukemic activity which is currently tested for treatment of acute and chronic leukemias, either alone or in combination with other agents. Since HHT showed a low efficacy in refractory and relapsed acute leukemia and in the blastic phase of chronic myeloid leukemia (CML) which are frequently characterized by an overexpresion of the multidrug resistance (MDR)-related P170-glycoprotein, we postulated a relationship between the poor antileukemic effect of HHT in these leukemias and the expression of P170-glycoprotein. For this reason, sensitive (LOVO109 and CEM) and MDR (LOVO DX and CEM VLB) cell lines were exposed to HHT with or without some MDR modifiers, namely, Cyclosporine A (CyA), the Cyclosporine derivative SDZ PSC 833 (PSC), and the D-isomer of Verapamil (DVRP).

Evaluation of the clinical relevance of the anionic glutathione-s-transferase (GST pi) and multidrug resistance (mdr-1) gene coexpression in leukemias and lymphomas.

By using RNA slot-blot technique, the frequency and the degree of GST pi and mdr-1 gene coexpression were investigated in 23 AML patients, 9 ALL, 9 CLL and 11 cases of NHL in an attempt to study their clinical and prognostic relevance. GST pi and mdr-1 levels were expressed as arbitrary units (U) with respect to the negative controls (U = 0), MCF7 and HL60 sensitive cell lines, and the positive controls (U = 10), MCF7/DOXO and HL60/DNR resistant cell lines. The concomitant GST pi/mdr-1 gene overexpression showed a negative prognostic value in the set of newly diagnosed AML pts (10 cases), furthermore higher GST pi and mdr-1 mRNA levels were averagely detected in the relapsed/resistant ALL pts (4 cases), and in CLL (7 cases) and NHL (8 cases) heavily pretreated patients who were unresponsive to chemotherapy and with a disease progression.

Overexpression of MDR-related p170 glycoprotein in chronic myeloid leukemia.

Background And Methods: Philadelphia (Ph) positive chronic myeloid leukemia (CML) cannot be induced into a true remission with conventional chemotherapy. Blast cells and precursors obtained from 51 Ph+ CML cases were assayed for expression of the multidrug resistance (MDR)-associated glycoprotein (p170) by immunocytochemistry (APAAP) with the MRK-16 monoclonal antibody.

Results And Conclusions: Positive cells were found in 11/17 cases in chronic phase (65%), in 4/8 cases in accelerated phase, and in 23/26 cases in blastic phase (89%).

p170-dependent multidrug resistance. Restoring full sensitivity to idarubicin with verapamil and cyclosporin A derivatives.

Background: Cell sensitivity to anthracyclines and other drugs depends on several factors, including overexpression of a 170Kd transmembrane glycoprotein (P170) that enhances drug efflux from the cells. Since the result of treatment is negatively related to the expression of P170 in leukemia, malignant lymphoma and other tumors, it is important to investigate drugs and methods that can modify multidrug resistance (MDR).

Materials And Methods: Using an MTT-microcultured tetrazolium colorimetric method, we assayed sensitivity to daunorubicin (DNR) and to its 4-demethoxy derivative idarubicin (IDA) in two MDR cell lines (CEM VLB and LOVO DX) and in their respective non-MDR parental lines (CEM and LOVO 109), with and without three MDR modifiers, namely the D-isomer of verapamil (DVRP), cyclosporin A (CyA) and the new CyA derivative SDZ PSC 833.

The expression of the multidrug resistance related glycoprotein in adult acute lymphoblastic leukemia.

Background: More than 50% of adults with acute lymphoblastic leukemia (ALL) actually die with resistant leukemia. The multidrug resistance (MDR) related P170 glycoprotein may be involved in treatment failure.

Methods: P170 content of leukemic cells was assayed by immunocytochemistry with the MRK-16 monoclonal antibody in 41 consecutive cases of adult ALL (27 at onset and 14 at relapse).

D-verapamil downmodulates P170-associated resistance to doxorubicin, daunorubicin and idarubicin.

Verapamil (VRP) is an effective modulator of P170-associated multidrug resistance (MDR), but its clinical application is limited by cardiovascular side-effects. The D-isomer of VRP (D-VRP) is 10 times less active than the racemic mixture on the cardiovascular system, but retains a MDR modulating activity. Daunorubicin (DNR) and doxorubicin (DX) are two anthracyclines whose cytotoxicity is strongly related with the expression of P170, while their respective lipophylic derivatives idarubicin (IDA) and iododoxorubicin (IDX) are less P170-dependent.