In vivo effects of monoclonal antibodies against rat beta(2) integrins on kidney ischemia-reperfusion injury.

BACKGROUND: Ischemia-reperfusion (IR) involves adhesion of leukocytes to the activated endothelium, leading to tissue damage. CD11/CD18 beta(2) integrins interact with their ligands on endothelial cells and may therefore represent a therapeutic target for the prevention of IR. We investigated the effects of three monoclonal antibodies (mAbs) that recognize epitopes of heavy or light chain of the beta(2) integrins on IR in kidneys. METHODS: Uninephrectomized Fischer rats were subjected to 45 or 60 min of renal ischemia, treated with intravenously anti-beta(2) integrin monoclonal antibodies (anti-CD11a, anti-CD11b, and anti-CD18) 5 min prior to reperfusion, and compared to a nontreated group. Serum creatinine, blood urea nitrogen (BUN), and kidney histopathological damages were assessed at 1, 2, and 7 days after ischemia. RESULTS: After 45 and 60 min of ischemia, serum creatinine and BUN were significantly higher in the control than in animals treated with anti-CD11a and anti-CD18 at 24 and 48 h. Administration of anti-CD11b had a beneficial effect on renal function after 45 min but not after 60 min of ischemia. Histologic and immunostaining studies demonstrated mild tubular necrosis and less leukocyte infiltration in the anti-CD11a- and anti-CD18-treated groups compared to the control group. CONCLUSION: These results indicate that selected antibodies to CD11a/CD18 may decrease kidney IR injury when administered prior to reperfusion.

Improvement of prognosis in refractory and relapsed acute promyelocytic leukemia over recent years: the role of all-trans retinoic acid therapy.

With the aim of determining the ability of all-trans retinoic acid (ATRA) to improve prognosis in refractory and relapsed acute promyelocytic leukemia (APL), the data of 45 patients resistant to previous conventional chemotherapy or in first relapse were retrospectively reviewed. Thirty-seven patients presented with typical M3, five with variant form (M3v), and three with intermediate form. Seven patients died before any chemotherapy could be given. Thirty-five patients received one course of chemotherapy combining anthracyclines and cytarabine without (n = 22) or with ATRA (n = 13), according to different protocols. One elderly patient received only ATRA, and two patients received only low-dose cytarabine. Nine patients died within 4 weeks of relapse. A complete remission (CR) was achieved in 29 of the 38 patients retreated after first relapse or primary failure (76.3%, 95% CI: 60-89%). Among relapsed patients, four of five patients who had initially received ATRA therapy achieved a second CR when retreated by ATRA. The median second disease-free survival (DFS) was 23.3 months. Overall median survival was 7.8 months, with a 5-year survival rate of 29% (95% CI: 14-44%). Parameters found to be associated with decreased second CR rate were presence of hemorrhages and hemostatic disorder, and high levels of GGT at the time of relapse. Factors associated with short survival were WHO performance status > 1, high serum LDH levels, and coagulopathy at time of relapse. Use of ATRA at time of relapse (n = 14) was significantly associated with higher CR rates (p = 0.008), longer DFS (median not reached versus 7.9 months; p = 0.05), and longer survival after first relapse (median 32.3 months versus 4.4 months; p = 0.003). In the multivariate analysis, the only factor predictive of poor prognosis for overall survival was the absence of ATRA therapy at relapse. We conclude that ATRA is effective in the treatment of relapsed or refractory APL and appears superior to chemotherapy alone.

Occurrence of T-cell lymphoma in a patient with acute myelogenous leukemia.

We describe a patient with AML with a monocytic component who developed a T-lymphoblastic lymphoma. Lymphoma was diagnosed 9 months following AML diagnosis. To our knowledge, this is the first report of phenotypically documented T-cell lymphoma following AML. The questions relating to the pathogenesis of the two malignancies are discussed.

Surface marker expression in acute myeloid leukaemia at first relapse.

Surface markers were studied at first relapse in 66 cases of acute myeloid leukaemia (AML), using a panel of five monoclonal antibodies directed to CD13, CD14, CD15, CD33 and CD34 antigens. At time of relapse, there was increased expression of CD33 (P = 0.002) and CD34 (P = 0.0001), and decreased expression of CD13 (P = 0.004) and CD15 (P = 0.0001) antigens by comparison to initial diagnosis. There was no strict correlation with the FAB classification. However, CD13 and CD33 expression changes preferentially affected granulocytic leukaemias. At relapse, CD14 and CD34 were significantly more expressed in monocytic than in granulocytic AML (P = 0.01 and 0.003 respectively). In a multivariate analysis, CD34 expression was associated with a low CR rate (P = 0.001) and short survival (P = 0.05), whereas CD15 expression was associated with long survival (P = 0.0004). These results suggest that AML tends to relapse with a less differentiated phenotype than observed at diagnosis and that AML with less differentiated phenotype is of poor prognosis after first relapse, as also observed at diagnosis.

Prognostic Factors in Acute Promyelocytic Leukemia: A Retrospective Study of 67 Cases.

In a cohort of 67 adult patients with newly diagnosed untreated acute promyelocytic leukemia (APL), the initial clinical and biological parameters were submitted to multivariate analysis for potential prognostic significance. Median age of the patients was 40 years and the hematologic characteristics of the patients were those regularly seen. Complete remission (CR) was achieved in 43 cases (64%). Fourteen patients died within 4 weeks of diagnosis, due to severe hemorrhage. Factors predictive of hemorrhagic death in the multivariate analysis were hyperuricemia (p = 0.001), splenomegaly (p = 0.009), anemia (p = 0.02), high serum levels of LDH (p = 0.02), increased prothrombin time (p = 0.04), and hypercreatininemia (p = 0.05). Pretreatment patient characteristics for poor prognosis and achieving CR were hyperuricemia (p = 0.0002), splenomegaly (p = 0.01), anemia (p = 0.02), and lymphadenopathy (p = 0.04). The median disease-free survival (DFS) was 15.6 months. Poor prognostic factors for DFS were hyperuricemia (p = 0.007), and splenomegaly (p = 0.03). Maintenance chemotherapy had no statistically significant impact on CR duration. Median survival duration was 10 months. Poor prognostic factors for survival were hyperuricemia (p = 0.0005), and elevated serum LDH levels (p = 0.01).

Correlations between cytogenetics and morphology in myelodysplastic syndromes.

In order to detect possible relationships between cytogenetic abnormalities and morphologic features in myelodysplastic syndromes (MDS), 48 patients with MDS were investigated. Clonal cytogenetic abnormalities were present in bone marrow cells from 27 patients (56%). The most frequent single anomaly was del (5 q) (10 cases), followed by monosomy 7 (3 cases), trisomy 8 (3 cases) and del (20 q) (2 cases). Complex anomalies were present in 6 patients. Morphologically, according to the French-American-British (FAB) classification: 17 cases were considered as refractory anemia (RA), 17 as RA with excess of blasts (RAEB), 2 as RAEB in transformation, 2 as acquired idiopathic sideroblastic anemia and 10 as chronic myelomonocytic leukemia. With regard to the FAB classification, del (5 q) was often associated with RA and complex cytogenetic anomalies with RAEB. When myelodysplasia was studied in individual myeloid lineages, del (5 q) was associated with hypolobulated megakaryocytes, monosomy 7 with micromegakaryocytes and complex chromosomal anomalies with the association of two or more features of dysmegakaryocytopoiesis. Del (11 q) was associated with increased iron storage and del (20 q) with marked dyserythropoiesis. No correlation was observed between cytogenetic anomalies and features of dysgranulocytopoiesis.

DNA, RNA, and protein content in adult acute myeloid leukemia: effects of cytostatic drugs in vivo.

DNA, RNA, and/or protein cellular content were studied by flow cytometry in 52 cases of acute myeloid leukemia before and on day 4 of remission induction treatment. Bone marrow (BM) samples were stained after fixation by acridine orange for DNA and RNA content (37 cases) and by propidium iodide and fluorescein isothiocyanate for DNA and protein content (52 cases). A positive correlation was found between pretreatment protein content and BM blast involvement: the higher the percentage of blasts in BM smears the higher the mean protein content (p less than 0.05). Protein content was higher in monoblastic leukemia (M4 and M5) than in the granulocytic types (M1, M2, M3) (p less than 0.05). S + G2 + M was higher in patients with protein content below 80 arbitrary units than in the subgroup with protein content above this threshold (p less than 0.05). Pretreatment RNA content, estimated by the RNase-sensitive fraction of G1 cells, was significantly higher in undifferentiated and M1 leukemias than in the other cytological groups (p less than 0.0001). This fraction was higher in patients who subsequently achieved complete remission, but it was not related to BM blast involvement or proliferative fraction of cells. During cytostatic treatment the changes in RNA and protein content did not follow a typical pattern. The connections between variations of DNA, RNA, and protein content and prognosis are examined and their possible relation to drug-induced blast cell maturation is discussed.

Treatment of acute myeloid leukemia in elderly patients. A retrospective study.

In an attempt to rationalize the use of therapy in acute myeloblastic leukemia (AML) in elderly patients, 69 cases of primary AML in patients older than 60 years of age were reviewed retrospectively. Therapy was empirical and 12 patients received supportive care (SC) only, 35 received aggressive chemotherapy (AC), and 22 received low-dose cytosine arabinoside (LD-araC). Patients receiving SC only often had a poor Karnofski index and their median survival was 17 days. Aggressive chemotherapy yielded complete remissions (CR) in 48% of the patients, whereas 23% of the patients had resistant disease (RD) and 29% had other failures (OF). Low-dose araC, which was administered to patients significantly older than those receiving AC, yielded 23% CR, 68% RD, and 9% OF, with important hematologic toxicity in most patients. Median survival was 211 days in patients receiving AC and 235 days in patients treated with LD-araC. Survival beyond 2 years from diagnosis was noted in the AC group only. A low Karnofski index was the strongest factor in poor prognosis, while age was not a prognostic factor. The initial characteristics of the patients did not allow us to define groups of patients who should be treated by either AC or LD-araC. We concluded that the decision to treat patients actively should rely more on the patient's general condition and socio-economical criteria than on age.

Myelodysplastic syndromes. A multiparametric study of prognostic factors in 336 patients.

Two groups of patients with a myelodysplastic syndrome (MDS) were analyzed by univariate (log-rank test) and multivariate (logistic regression) analyses to detect the most important prognostic factors. By stepwise analysis, the variables found to have prognostic significance for death were as follows: age, percentage of marrow blasts, presence of circulating blasts, and number of platelets. The variables found significant for predicting progression to acute leukemia (AL) were as follows: hemoglobin level, percentage of marrow blasts, and presence of circulating blasts. The first group of 193 patients was used to build a prognostic index which reflected the probability of a given patient dying or progressing to AL within 6, 9, or 12 months. The application of this prognostic index to a test group of 143 patients was used to determine the expected error rate and the validity of the prediction rule.

Influence of daunorubicin and cytarabine sequencing on the outcome of therapy in acute myelogenous leukemia: a randomized trial.

Ninety-seven patients less than or equal to 70 years of age with previously untreated primary acute myeloblastic leukemia were randomly treated with either the DAT or TAD regimen: daunorubicin (70 mg/m2/day) administered on Days 1-3 (DAT) or 5-7 (TAD) of a 7-day sequence consisting of cytarabine (200 mg/m2/day) and 6-thioguanine (200 mg/m2/day). Complete responders received consolidation, maintenance, and final intensification over 14 months using mostly the same drugs as during induction and administered in the same sequence. The regimens did not significantly differ from each other with regard to toxicity or efficacy. Complete remission rate was 80% in the two groups, and median duration of complete remission was 549 days with DAT and 518 days with TAD.

Day 4 bone marrow aspirate for prediction of resistance to induction chemotherapy in acute myeloid leukemia.

Bone marrow aspirate was performed on day 4 of a 7-day induction chemotherapy regimen using daunorubicin, cytosine arabinoside and thioguanine in 42 patients with acute myeloid leukemia (AML). The mean percentage of remaining abnormal cells in day 4 bone marrow was significantly higher in patients having resistant disease (RD) than in patients entering complete remission (CR). Except for patients with FAB M3 AML, most patients who had more than 40% abnormal cells in their day 4 bone marrow had RD. In addition, patients entering CR despite having more than 40% abnormal cells remaining in their day 4 bone marrow seemed to have short CR.