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J Cortes

Publications and source records attributed to J Cortes.

At least 55 records · Page 3Linked to original sources
PubMed2000

Promising approaches in acute leukemia.

In the last few decades, there has been a significant improvement in the prognosis of patients with acute leukemias. Still, the majority of patients succumb to these diseases. In recent years there has been a great surge in the understanding of the molecular mechanisms of disease which have provided us with new targets for anti-leukemia therapy. These range from chemotherapeutic agents with novel mechanisms of action, such as topoisomerase I inhibitors or demethylating agents, to reversal of drug-resistance mechanisms, to monoclonal antibodies directed against specific antigens, and targeted therapy that inhibit the function of molecules such as tyrosine kinases or Ras. The research on many of these agents is still in the early phases, but these new approaches offer the promise of finding a cure for the majority of patients with leukemia in the near future. Here we describe some of the promising approaches that are currently being investigated in the treatment of acute leukemias.

Acute Disease↗
PubMed2000

Results of treatment with hyper-CVAD, a dose-intensive regimen, in adult acute lymphocytic leukemia.

PURPOSE: To evaluate the efficacy and toxicity of Hyper-CVAD (fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone), a dose-intensive regimen, in adult acute lymphocytic leukemia (ALL). PATIENTS AND METHODS: Adults with newly diagnosed ALL referred since 1992 were entered onto the study; treatment was initiated in 204 patients between 1992 and January 1998. No exclusions were made because of older age, poor performance status, organ dysfunction, or active infection. Median age was 39.5 years; 37% were at least 50 years old. Mature B-cell disease (Burkitt type) was present in 9%, T-cell disease in 17%. Leukocytosis of more than 30 x 10(9)/L was found in 26%, Philadelphia chromosome-positive disease in 16% (20% of patients with assessable metaphases), CNS leukemia at the time of diagnosis in 7%, and a mediastinal mass in 7%. Treatment consisted of four cycles of Hyper-CVAD alternating with four cycles of high-dose methotrexate (MTX) and cytarabine therapy, together with intrathecal CNS prophylaxis and supportive care with antibiotic prophylaxis and granulocyte colony-stimulating factor therapy. Maintenance in patients with nonmature B-cell ALL included 2 years of treatment with mercaptopurine, MTX, vincristine, and prednisone (POMP). RESULTS: Overall, 185 patients (91%) achieved complete remission (CR) and 12 (6%) died during induction therapy. Estimated 5-year survival and 5-year CR rates were 39% and 38%, respectively. The incidence of CNS relapse was low (4%). Compared with 222 patients treated with vincristine, doxorubicin, and dexamethasone (VAD) regimens, our patients had a better CR rate (91% v 75%, P <.01) and CR rate after one course (74% v 55%, P <.01) and better survival (P <.01), and a smaller percentage had more than 5% day 14 blasts (34% v 48%, P =.01). Previous prognostic models remained predictive for outcome with Hyper-CVAD therapy. CONCLUSION: Hyper-CVAD therapy is superior to our previous regimens and should be compared with established regimens in adult ALL.

Adolescent↗
PubMed2000

Cyclophosphamide, ara-C and topotecan (CAT) for patients with refractory or relapsed acute leukemia.

Topotecan is a topoisomerase I inhibitor with significant activity in patients with myelodysplastic syndrome and chronic myelomonocytic leukemia. Pre-clinical data suggest a synergistic activity with DNA damaging agents such as cyclophosphamide, where topotecan might prevent the repair of cyclophosphamide-induced DNA damage. We thus designed a combination including cyclophosphamide 500 mg/m2 every 12 hours given on days 1 to 3; topotecan 1.25 mg/m2/day by continuous infusion on days 2 to 6, and cytosine arabinoside (ara-C) 2 g/m2 over 4 hours daily for 5 days on days 2 to 6 (CAT). Sixty six (63 evaluable) patients were treated. Fifty two patients had refractory (n=12) or relapsed (n=40) acute myelogenous leukemia (AML), and eleven had acute lymphocytic leukemia (ALL) (refractory n=3, relapsed n=8); their median age was 57 years (range, 18 to 79 years). Eleven patients (17%) achieved a complete remission (CR), and two patients (3%) had a hematologic improvement (HI; met all criteria for CR except for platelets < 100x10(9)/L), for an overall response rate of 20%. Responses occurred in 12 of 52 AML patients (23%), including 10 CR (19%) and 2 HI (4%), and in 1 of 11 patients with ALL (9%). Myelosuppression was universal; there were 23 episodes of pneumonia or sepsis and 18 episodes of fever of unknown origin complicating 74 courses of CAT. Non-hematologic toxicity was mostly gastrointestinal, including nausea, vomiting, diarrhea and mucositis, but was severe in only 8%. In summary, the CAT regimen is well tolerated and has significant anti-leukemia activity which warrants further investigation.

Acute Disease↗
PubMed2000

Myelodysplasia presenting as granulocytic sarcoma of mediastinum causing superior vena cava syndrome.

Granulocytic sarcomas (GS) are extramedullary tumor masses of immature myeloid cells, most frequently associated with hematological disorders including acute myeloid leukemia (AML), chronic myelogenous leukemia (CML), and myelodysplastic syndrome (MDS). Recent interest has centered upon the possible biologic properties that enable theses myeloid cells to adhere to tissues and establish a tumor mass. GS presenting as a mediastinal mass is relatively infrequent, and more uncommon is presentation with the superior vena cava syndrome. We present one such case and review some of the available literature.

Adult↗
PubMed2000

Outcome of Philadelphia chromosome-positive adult acute lymphoblastic leukemia.

Philadelphia chromosome (Ph)-positive acute lymphoblastic leukemia (ALL) represents the most common cytogenetic abnormality in adult ALL. It is found in 15% to 30% of patients, and its incidence increases with age. As in children, prognosis in Ph-positive adult ALL is poor. No therapeutic approach has had substantial impact on its unfavorable course. We analyzed the characteristics and outcome of newly diagnosed adults with Ph-positive ALL treated at the M. D. Anderson Cancer Center between 1980 and 1997. The diagnosis of patients was based on typical morphological and immunophenotypic criteria of marrow aspirate and biopsy specimens. Cytogenetic and molecular studies were also performed. A total of 67 patients were included in this study. From 1980 until 1991, 38 patients with Ph-positive ALL were treated with vincristine, Adriamycin, and dexamethasone (VAD), or with acute myeloid leukemia (AML)-like induction protocols. Since 1992 a total of 29 patients received induction therapy with an intensified treatment protocol, called "hyper-CVAD". The outcome of patients treated with standard and intensified treatment regimens was compared and results of our institution contrasted with data obtained from other centers. Ph-positive ALL was present in 67 of 498 patients with newly diagnosed ALL (13%). Patients with Ph-positive ALL had a higher median age (44 versus 34, P=0.007), higher median white blood cell (WBC) counts at presentation (25 versus 8, P=0.0002), and higher peripheral median percentage of blast counts (63 versus 40, P=0.023). FAB subtype L2 (70% versus 49%, P=0.001) and CALLA-positive pre-B immunophenotype (75% versus 37%, P<0.001) predominated among Ph-positive ALL. Myeloid marker coexpression was more frequent in Ph-positive ALL when compared with Ph-negative ALL (52% vs. 27% for CD13, P<0.001, and 44% vs. 27% for CD33, P=0.005). Among patients treated with hyper-CVAD, the complete remission (CR) rate was 90% versus 55% (P=0.002) with pre-hyper-CVAD regimens (VAD and AML-like induction protocols), the median CR duration was 43 weeks versus 32 weeks (P>0.5), median disease-free survival (DFS) was 42 weeks versus 29 weeks (P=0.008), and median survival was 66 weeks versus 45 weeks (P>0.5). Patients with hyperdiploid Ph-positive ALL on hyper-CVAD therapy achieved significantly longer CR duration and DFS than hypo- and pseudodiploid cases (59 weeks versus 42 and 31 weeks, P=0.02 and 0.04, respectively). In contrast, patients treated with regimens prior to hyper-CVAD had significantly shorter CR duration (21 weeks versus 33 and 29 weeks, P=0.03) and DFS with hyperdiploid karyotypes when compared to pseudodiploid and hypodiploid cases (16 weeks versus 30 and 13 weeks, P=0.008). In conclusion, our results demonstrate improved response rate and DFS with current intensive regimens (hyper-CVAD) in patients with Ph-positive ALL, but no advantage in overall survival.

Adult↗
PubMed2000

Serum beta-2 microglobulin levels are a significant prognostic factor in Philadelphia chromosome-positive chronic myelogenous leukemia.

Our objective was to investigate the prognostic significance of serum beta-2 microglobulin (B2M) levels among patients with chronic myelogenous leukemia (CML). All patients with Philadelphia chromosome-positive early chronic phase CML (i.e., within 1 year of diagnosis) treated with IFN alpha-based therapy at the M. D. Anderson Cancer Center between 1980 and 1997, in whom pretreatment B2M levels were available, were investigated. Two hundred one patients were evaluable. Their median B2M was 2.2 mg/dl (range, 1.1-20 mg/dl). Serum B2M levels were associated with other variables of prognostic significance, including age, spleen size, WBC count, percentage of peripheral and marrow blasts, and percentage of marrow basophils. Patients with B2M levels >2.9 mg/dl (ie., the upper quartile of the distribution) had a significantly lower rate of major cytogenetic response compared to those in the lower three quartiles (20 versus 52%; P < 0.01). They also had a shorter survival, with a 5-year survival rate of 48%, compared with 75% for those in the lower quartiles (P = 0.01). High B2M levels (>2.9 mg/dl) could identify a group of patients with an adverse outcome within patients in stage I disease (P = 0.02). Results for patients in stages 2-4 were inconclusive because of the small number of patients in these groups. We conclude that serum B2M levels are an important, and probably independent, prognostic factor for patients with CML in early chronic phase treated with IFN-based therapy.

Aged↗
PubMed2000

BAX and PKCalpha modulate the prognostic impact of BCL2 expression in acute myelogenous leukemia.

Previously, we demonstrated that the level of BCL2 expression is prognostic in acute myelogenous leukemia (AML). High levels of BCL2 correlate with an adverse outcome when associated with favorable and intermediate prognosis cytogenetics (FIPC), whereas low levels portend an adverse outcome when associated with unfavorable cytogenetics (UC). Because BCL2 function can be modulated by dimerization with family members, like BAX, or by phosphorylation by protein kinase C alpha (PKCalpha), we hypothesize that the relative expression of these proteins in primary leukemic cells might alter the prognostic impact of BCL2 expression. We therefore measured BAX and PKCalpha protein levels in peripheral blood mononuclear cell lysates from 165 newly diagnosed AML patients and correlated the expression of these proteins with BCL2 expression, patient survival, and remission induction success. Expression levels of BAX and PKCalpha were normalized against a control cell line, K562. BAX and PKCalpha expression levels were heterogeneous and did not correlate with the percentage of blasts in the sample (R2 = 0.01 and <0.01). The median expression of both was similar across FAB groups but the range was greater for M4. A similar distribution of expression was observed in all cytogenetic groups, except that patients with inversion 16 demonstrated lower levels of BAX. Individually, neither PKCalpha nor BAX expression was prognostic of response to induction therapy or survival. A similar outcome was obtained when patients were stratified by cytogenetics into FIPC and UC groups. However, the ratio of either BCL2:BAX (B2:BX) or PKCalpha*B2:BX (PK*B2:BX) was highly prognostic. Patients with FIPC and a lower ratio (less than median) of either B2:BX or PK*B2:BX had a significantly higher remission induction rate (88 versus 69%, P = 0.04) and longer survival (median: 141 versus 80.5 weeks, P = 0.007) compared with those with ratios more than median. For patients with UC, values of either B2:BX or PK*B2:BX below the median had an inferior response rate to induction therapy (35 versus 78%, P = 0.0006) and inferior survival outcomes (median survival: 11 versus 53 weeks, P = 0.00002). Interestingly, FIPC and UC patients with antiapoptotic ratios (defined as B2:BX or PK*B2:BX more than median) had identical response rates and survival outcomes. In multivariate analyses, the compound variables of cytogenetics and B2:BX, or PK*B2:BX were independent predictors of survival. These results suggest that expression levels of proteins that affect the functional status of BCL2 modify the prognostic impact of BCL2 and suggest that the role of apoptosis in different cases of AML varies independently in the different cytogenetic subgroups.

Adolescent↗
PubMed1999

Chronic myelogenous leukemia in nonlymphoid blastic phase: analysis of the results of first salvage therapy with three different treatment approaches for 162 patients.

BACKGROUND: The prognoses of patients with chronic myelogenous leukemia in blastic phase (CML-BP) are extremely poor. Treatment of patients with nonlymphoid CML-BP is associated with very low response rates, a median survival of 2-3 months, and significant toxicities. The aim of this study was to evaluate the results of therapy in CML-BP with different treatments in relation to response rate, survival, and toxicity. METHODS: A total of 162 adults patients with a diagnosis of nonlymphoid CML-BP referred from 1986 to 1997 were included in this analysis. Only first salvage therapy was considered for the purpose of this analysis. The blastic phase of CML was defined by the presence of 30% or more blasts in the blood or bone marrow, or extramedullary disease. Ninety patients were treated with intensive chemotherapy, 31 with decitabine, and 41 with other single agents. RESULTS: Thirty-six patients (22%) had an objective response. Response rates were similar among patients treated with intensive chemotherapy (28%) or with decitabine (26%). In aggregate, other single agents showed objective response rates of 7%. The median duration of remission for all patients was 29 weeks and the median overall survival 22 weeks. Patients treated with decitabine showed a trend toward better survival, despite a higher percentage of older patients (P < 0.004). The median survival times were 29 weeks with decitabine, 21 weeks with intensive chemotherapy, and 22 weeks with other agents. When only older patients were considered, survival was significantly better with decitabine versus other treatments (P < 0.01). A multivariate analysis of prognostic factors for survival confirmed the independent, significant favorable effect of decitabine therapy (P = 0.047). In all groups complications of myelosuppression were the most significant side effects. Severe nonhematologic toxicities were not observed in patients treated with decitabine; they occurred in 20% and 17% of patients treated with intensive chemotherapy or other single agents, respectively. CONCLUSIONS: Compared with intensive chemotherapy, decitabine showed favorable results, with similar objective response rates, a better nonhematologic toxicity profile, and a trend for better survival, particularly among older patients. Studies will now attempt to combine decitabine with other promising approaches, such as homoharringtonine, low dose cytarabine, and interferon-alpha, in all CML phases.

Adolescent↗
PubMed1999

Combination therapy with methotrexate, vincristine, polyethylene-glycol conjugated-asparaginase, and prednisone in the treatment of patients with refractory or recurrent acute lymphoblastic leukemia.

BACKGROUND: L-asparaginase in combination with methotrexate has synergistic antileukemic activity in a schedule-dependent fashion. A new preparation of L-asparaginase, polyethylene-glycol conjugated (PEG)-asparaginase, is a pharmacologically different formulation of L-asparaginase with distinct properties including a longer half-life and less immunogenic properties. METHODS: Patients with refractory or recurrent acute lymphoblastic leukemia (ALL) were treated with a combination of methotrexate (MTX), vincristine, PEG-asparaginase, and prednisone (MOAP). The treatment was comprised of MTX, 100 mg/m(2) intravenously (i.v.), over 15 minutes on Days 1 and 14; PEG-asparaginase, 2500 IU/m(2), with a maximum dose of 3750 IU i.v. approximately 4-6 hours after MTX on Days 1 and 14; vincristine, 1.4 mg/m(2) (maximum dose, 2 mg) i.v., over 15 minutes on Days 1, 7, and 14; and prednisone, 200 mg daily orally, on Days 1-5 and 14-19. RESULTS: Thirty-two patients with a median age of 34 years (range, 20-74 years) were treated. Eight patients (25%) had ALL that was refractory to prior therapy and 24 patients (75%) had recurrent disease. Seven patients (22%) achieved a complete remission (CR). Five patients (16%) died early due to infections. Features associated with a poor response were high pretreatment lactate dehydrogenase levels and Philadelphia chromosome positive disease. The median duration of CR was 16 weeks and the overall median survival after MOAP therapy was 12 weeks. Anaphylactic reactions were not observed during MOAP combination therapy. CONCLUSIONS: MOAP is an active regimen in patients with refractory or recurrent ALL. This regimen is well tolerated and is not associated with allergic reactions. However, further studies regarding the pharmacologic interaction of MTX with PEG-asparaginase are needed to optimize this regimen.

Adult↗
PubMed1999

Primary refractory and relapsed adult acute lymphoblastic leukemia: characteristics, treatment results, and prognosis with salvage therapy.

BACKGROUND: Relapses continue to be problematic for adults with acute lymphoblastic leukemia (ALL). New therapies generally are first tested in the salvage setting prior to incorporation into frontline regimens. Defining the prognosis at relapse (or at failure of induction) and subsequently predicting outcome would be useful to select the population in whom to test new strategies, rather than attempting traditional reinduction therapy. METHODS: Between March 1980 and March 1997, 314 eligible adults with primary refractory (24%) or primary relapsed (76%) ALL were treated with various chemotherapy or stem cell transplantation (SCT) regimens. The Cox proportional hazards model was used to assess biologic factors and disease history in relation to survival. RESULTS: A complete remission (CR) was achieved in 97 patients (31%), 21% died prior to a response, and 49% were refractory to salvage therapy. Of the 76 patients refractory to induction therapy for their de novo ALL, 26 patients (34%) achieved a CR with salvage therapy. The median overall CR duration was 6 months. The median overall survival was 5 months; 24% of the patients were alive at 1 year, and the projected survival at 5 years was 3%. Nineteen patients were alive at the time of last follow-up, 10 with 6 weeks to 10 years of continuous CR from the time of their first salvage therapy. SCT consolidation in second CR was performed in 25% of patients; 28% of those who received allogeneic SCT remain in continuous CR at 4 months, 2(1/2) years, 3(1/2) years, and 10 years, whereas all 8 who received autologous SCT have relapsed. Favorable factors for longer survival by multivariate analysis were age <40 years, absence of circulating blasts, and first CR duration longer than 1 year. Patients were stratified into 4 risk groups: Group 1, with no unfavorable features or only short initial CR duration; Group 2, with only increased age or peripheral blasts; Group 3, with any 2 unfavorable features; and Group 4, with all 3 unfavorable features. The median survival times for each group were 11, 6, 4, and 2 months, respectively; 1-year survival rates were 44%, 25%, 12%, and 9%, respectively (P < 0.01). The resulting model was also predictive for CR rates; the corresponding CR rates were 47%, 35%, 14%, and 9%, respectively (P < 0.01). CONCLUSIONS: Salvage therapy for adult ALL patients continues to yield poor results, but it is an area of research where it may be possible to discover new agents or strategies to be incorporated into frontline therapy. The prognostic model derived will be utilized prospectively to select patients for new therapeutic strategies involving such novel agents as liposomal compounds, purine nucleoside phosphorylase inhibitors, and monoclonal antibodies.

Adolescent↗
PubMed1999

Molecular remissions induced by liposomal-encapsulated all-trans retinoic acid in newly diagnosed acute promyelocytic leukemia.

All-trans retinoic acid administered orally (oral ATRA) may not regularly lead to either molecular complete remissions (CRs) or prolonged hematologic CRs (HCR) unless combined with chemotherapy. Because serum tretinoin concentrations are higher, and maintained longer, after use of liposomal-encapsulated ATRA (lipoATRA) rather than oral ATRA, we investigated lipoATRA monotherapy in newly diagnosed acute promyelocytic leukemia (APL). Patients received lipoATRA 90 mg/m(2) every other day for remission induction. The same dose was given 3 times a week until 9 months had elapsed from HCR date. Treatment then stopped. Chemotherapy (idarubicin 12 mg/m(2) daily days 1-2 for 2 courses) was to be added only if 2 polymerase chain reaction (PCR) tests, performed 2 weeks apart, were positive at 3, 6, or 9 months from HCR date. The sensitivity level of the PCR was 10(-4). We treated 18 patients (median age, 54 years; median white blood cell [WBC] count 4,500/microL). The HCR rate was 12/18 (67%, 95% confidence interval [CI], 41% to 87%). This rate was similar to that we observed in a previous study using oral ATRA + idarubicin. Nine of 10 patients studied at HCR date were PCR-positive. Subsequently, however, overall (+/- idarubicin) rates of PCR positivity were 0/12 at 3 months, 1/10 at 6 months, 1/7 at 9 and 12 months, and 0/4 at 15 to 17 months. Idarubicin has been added in 3 patients, with this addition occurring at 6 months in 2 patients and at 9 months in 1 patient. Among patients who had not received idarubicin when the PCR was evaluated, 0 of 12 were PCR-positive at 3 months, 1 of 10 was positive at 6 months, 1 of 6 was positive at 9 months, 0 of 4 were positive at 12 months, and 0 of 3 were positive at 15 to 17 months. Morphologic APL has recurred in 1 patient, with a median follow-up time of 13 months in the 11 patients remaining in first CR. The median follow-up time is 91/2 months (range, 3 to 17) in the 9 patients who have received only lipoATRA and who remain PCR-negative and in first CR. Our data suggest that lipoATRA is an effective means of producing molecular CR in newly diagnosed APL.

Administration, Oral↗
PubMed1999

Multidrug resistance protein expression in chronic myeloid leukemia: associations and significance.

BACKGROUND: Overexpression of the multidrug resistance gene (MDR1) product, the MDR1 protein (MDR1), has been associated with poor prognosis in several hematologic malignancies. The significance of MDR1 levels in patients with chronic myeloid leukemia (CML) has not been established. METHODS: The authors investigated MDR1 levels and their association with patient and tumor characteristics, responsiveness to therapy, and long term prognosis in 198 CML patients. These included 127 patients in early chronic phase (ECP) CML, 31 patients in late chronic phase (LCP) CML, and 40 patients in accelerated or blastic phase CML. MDR1 expression was analyzed by Western blot analysis and quantitative solid-phase plate radioimmunoassay. MDR1 levels were measured on cell lysates obtained from the bone marrow mononuclear cell fraction. Expression was compared in relation to the median derived from 36 normal control samples. RESULTS: Among patients with CML, high levels of MDR1 were found in 73 of 127 ECP (57%), 20 of 31 LCP (65%), 8 of 27 in accelerated phase (30%), and 8 of 13 in blastic phase (62%) (P value not significant). Furthermore, among the 127 ECP CML patients, high MDR1 levels were associated with age >/=50 years (69% vs. 51%; P < 0. 05), thrombocytosis >700 x 10(9)/L (84% vs. 53%; P < 0.01), and leukocyte counts </=50 x 10(9)/L (70% vs. 46%; P < 0.01). Response to interferon alpha (IFN-alpha) was independent of MDR1 expression; major cytogenetic responses were recorded in 28 of 73 patients with high MDR1 levels and in 16 of 54 patients with low MDR1 levels (38% vs. 30%; P value not significant). No difference in survival based on MDR1 level was observed. A small subset of 17 patients with low MDR1 levels (<1 times normal) had a trend toward worse survival (median, 30 months vs. 73 months; 5-year survival rates of 34% vs. 65%; P = 0.03). CONCLUSIONS: The results of the current study demonstrate that MDR1 overexpression was not associated with disease progression, responsiveness to IFN-alpha therapy, or survival in patients with ECP CML.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1999

Thrombotic microangiopathy associated with interferon therapy for patients with chronic myelogenous leukemia: coincidence or true side effect?

BACKGROUND: Interferon-alpha (rIFN-alpha) is an established therapy for patients with myeloproliferative disorders. Unusual immune-mediated side effects have been associated with rIFN-alpha therapy. The association of rIFN-alpha therapy with hemolytic uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP) has been reported infrequently. METHODS: Two patients with chronic myelogenous leukemia (CML) treated with rIFN-alpha-based regimens at the University of Texas M. D. Anderson Cancer Center developed thrombotic microangiopathy (HUS/TTP). The course of their disease is described. A third patient who developed renal failure while receiving rIFN-alpha therapy and had no other causative factor for his renal failure is also described. RESULTS: The patients were ages 24, 49, and 36 years, and they had received rIFN-alpha therapy for 37, 67, and 92 months, respectively, prior to the development of the disorder. One patient had discontinued rIFN-alpha 1 month before the event because of presumed rIFN-alpha-related cardiomyopathy. Two patients received hydroxyurea and cytarabine as part of their therapy. No patient was receiving any medication known to be associated with HUS/TTP. None had a history of diarrheal illness, but Escherichia coli OH157.H7 was grown from the stool of one patient. Two patients responded to plasmapheresis with normalization of counts and other indices, but both developed renal failure and became dependent on dialysis. One patient had evidence of disease progression and died of multiorgan failure. The third patient required dialysis for 18 months but is currently off dialysis; this patient has some residual renal impairment. CONCLUSIONS: Although no definitive association between rIFN-alpha therapy and thrombotic microangiopathies can be concluded from these data, these and other previously reported cases suggest that HUS/TTP is a rare side effect of rIFN-alpha therapy that should be managed in the standard fashion. Hypotheses regarding the mechanism underlying this association are discussed in this article.

Adult↗
PubMed1999

Randomized phase II study of fludarabine + cytosine arabinoside + idarubicin +/- all-trans retinoic acid +/- granulocyte colony-stimulating factor in poor prognosis newly diagnosed acute myeloid leukemia and myelodysplastic syndrome.

Preclinical data suggest that retinoids, eg, all-trans retinoic acid (ATRA), lower concentrations of antiapoptotic proteins such as bcl-2, possibly thereby improving the outcome of anti-acute myeloid leukemia (AML) chemotherapy. Granulocyte colony-stimulating factor (G-CSF) has been considered to be potentially synergistic with ATRA in this regard. Accordingly, we randomized 215 patients with newly diagnosed AML (153 patients) or high-risk myelodysplastic syndrome (MDS) (refractory anemia with excess blasts [RAEB] or RAEB-t, 62 patients) to receive fludarabine + ara-C + idarubicin (FAI) alone, FAI + ATRA, FAI + G-CSF, or FAI + ATRA + G-CSF. Eligibility required one of the following: age over 71 years, a history of abnormal blood counts before M.D. Anderson (MDA) presentation, secondary AML/MDS, failure to respond to one prior course of chemotherapy given outside MDA, or abnormal renal or hepatic function. For the two treatment arms containing ATRA, ATRA was given 2 days (day-2) before beginning and continued for 3 days after completion of FAI. For the two treatment arms including G-CSF, G-CSF began on day-1 and continued until neutrophil recovery. Patients with white blood cell (WBC) counts >50,000/microL began ATRA on day 1 and G-CSF on day 2. Events (death, failure to achieve complete remission [CR], or relapse from CR) have occurred in 77% of the 215 patients. Reflecting the poor prognosis of the patients entered, the CR rate was only 51%, median event-free survival (EFS) time once in CR was 36 weeks, and median survival time was 28 weeks. A Cox regression analysis indicated that, after accounting for patient prognostic variables, none of the three adjuvant treatment combinations (FAI + ATRA, FAI + G, FAI + ATRA + G) affected survival, EFS, or EFS once in CR compared with FAI. Similarly, there were no significant effects of either ATRA ignoring G-CSF, or of G-CSF ignoring ATRA. As previously found, a diagnosis of RAEB or RAEB-t rather than AML was insignificant. There were no indications that the effect of ATRA differed according to cytogenetic group, diagnosis (AML or MDS), or treatment schedule. Logistic regression analysis indicated that, after accounting for prognosis, addition of G-CSF +/- ATRA to FAI improved CR rate versus either FAI or FAI + ATRA, but G-CSF had no effect on the other outcomes. We conclude that addition of ATRA +/- G-CSF to FAI had no effect on CR rate, survival, EFS, or EFS in CR in poor prognosis, newly diagnosed AML or high-risk MDS.

Acute Disease↗
PubMed1999

Methylation of the ABL1 promoter in chronic myelogenous leukemia: lack of prognostic significance.

The BCR-ABL chromosomal translocation is a central event in the pathogenesis of chronic myelogenous leukemia (CML). One of the ABL1 promoters (Pa) and the coding region of the gene are usually translocated intact to the BCR locus, but the translocated promoter appears to be silent in most cases. Recently, hypermethylation of Pa was demonstrated in CML and was proposed to mark advanced stages of the disease. To study this issue, we measured Pa methylation in CML using Southern blot analysis. Of 110 evaluable samples, 23 (21%) had no methylation, 17 (15%) had minimal (<15%) methylation, 12 (11%) had moderate methylation (15% to 25%), and 58 (53%) had high levels of methylation (>25%) at the ABL1 locus. High methylation was more frequent in advanced cases of CML. Among the 76 evaluable patients in early chronic phase (ECP), a major cytogenetic response with interferon-based therapy was observed in 14 of 34 patients with high methylation compared with 19 of 42 among the others (41% v 45%; P value not significant). At a median follow-up of 7 years, there was no significant difference in survival by ABL1 methylation category. Among patients who achieved a major cytogenetic response, low levels of methylation were associated with a trend towards improved survival, but this trend did not reach statistical significance. Thus, Pa methylation in CML is associated with disease progression but does not appear to predict for survival or response to interferon-based therapy.

Blotting, Southern↗
PubMed1999

Long-term angiographic results of stenting in chronic total occlusions: influence of stent design and vessel size.

BACKGROUND: Although coronary stenting has decreased the high restenosis rate associated with percutaneous transluminal coronary angioplasty of chronic total occlusions (CTOs), the results are still less satisfactory than those found in nonoccluded lesions, at least as reported with the Palmaz-Schatz stent. The present work compares the restenosis rate of other stent designs with that of the Palmaz-Schatz stent. METHODS: We studied the long-term angiographic outcome of 120 CTOs successfully recanalized with balloon-expandable stents and without concomitant debulking techniques. Angiographic follow-up and full quantitative coronary angiography analysis was prospectively performed in all patients. Three different stent designs were compared: Palmaz-Schatz (n = 47), coil (n = 24), and multicellular (n = 49). Particular attention was paid to their performance in vessels of 3 mm or less and greater than 3 mm in diameter. Restenosis was defined as a 50% or greater diameter stenosis at follow-up. RESULTS: Multicellular stents were implanted more frequently in the left anterior descending artery and in patients with multivessel disease. No other significant differences in clinical or angiographic baseline characteristics, including vessel size, were noted between groups. At follow-up, multicellular stents presented a lower restenosis rate (22% vs 36% and 58% in the Palmaz-Schatz and coil stent groups, respectively; P =.01 ) and larger minimal luminal diameters (1.92 +/- 0.85 mm vs 1.73 +/- 0.98 and 1.38 +/- 0.83 mm in the Palmaz-Schatz and coil stent groups, respectively; P = 0.0). The superiority of the multicellular stent design resulted from a lower restenosis rate in vessels of 3.0 mm or less in diameter (20% vs 47% and 79% in the Palmaz-Schatz and coil stent groups, respectively; P =.006). CONCLUSIONS: These results suggest that the restenosis rate after stent recanalization of CTOs is influenced by both stent design and vessel size and may indicate a superiority of multicellular over Palmaz-Schatz and coil stent designs for this purpose.

Coronary Angiography↗
PubMed1999

Molecular basis of Celmer's rules: the role of two ketoreductase domains in the control of chirality by the erythromycin modular polyketide synthase.

BACKGROUND: Polyketides are compounds that possess medically significant activities. The modular nature of the polyketide synthase (PKS) multienzymes has generated interest in bioengineering new PKSs. Rational design of novel PKSs, however, requires a greater understanding of the stereocontrol mechanisms that operate in natural PKS modules. RESULTS: The N-acetyl cysteamine (NAC) thioester derivative of the natural beta-keto diketide intermediate was incubated with DEBS1-TE, a derivative of the erythromycin PKS that contains only modules 1 and 2. The reduction products of the two ketoreductase (KR) domains of DEBS1-TE were a mixture of the (2S, 3R) and (2R,3S) isomers of the corresponding beta-hydroxy diketide NAC thioesters. Repeating the incubation using a DEBS1-TE mutant that only contains KR1 produced only the (2S,3R) isomer. CONCLUSIONS: In contrast with earlier results, KR1 selects only the (2S) isomer and reduces it stereospecifically to the (2S, 3R)-3-hydroxy-2-methyl acyl product. The KR domain of module 1 controls the stereochemical outcome at both methyl-and hydroxyl-bearing chiral centres in the hydroxy diketide intermediate. Earlier work showed that the normal enzyme-bound ketoester generated in module 2 is not epimerised, however. The stereochemistry at C-2 is therefore established by a condensation reaction that exclusively gives the (2R)-ketoester, and the stereo-chemistry at C-3 by reduction of the keto group. Two different mechanisms of stereochemical control, therefore, operate in modules 1 and 2 of the erythromycin PKS. These results should provide a more rational basis for designing hybrid PKSs to generate altered stereochemistry in polyketide products.

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