Differentiation syndrome in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline chemotherapy: characteristics, outcome, and prognostic factors. Blood. 2009;113:775-783. [PMID: 18945964 DOI: 10.1182/blood-2008-07-168617]

Novel retinoic acid receptor alpha agonists for treatment of kidney disease

Development of pharmacologic agents that protect podocytes from injury is a critical strategy for the treatment of kidney glomerular diseases. Retinoic acid reduces proteinuria and glomerulosclerosis in multiple animal models of kidney diseases. However, clinical studies are limited because of significant side effects of retinoic acid. Animal studies suggest that all trans retinoic acid (ATRA) attenuates proteinuria by protecting podocytes from injury. The physiological actions of ATRA are mediated by binding to all three isoforms of the nuclear retinoic acid receptors (RARs): RARα, RARβ, and RARγ. We have previously shown that ATRA exerts its renal protective effects mainly through the agonism of RARα. Here, we designed and synthesized a novel boron-containing derivative of the RARα-specific agonist Am580. This new derivative, BD4, binds to RARα receptor specifically and is predicted to have less toxicity based on its structure. We confirmed experimentally that BD4 binds to RARα with a higher affinity and exhibits less cellular toxicity than Am580 and ATRA. BD4 induces the expression of podocyte differentiation markers (synaptopodin, nephrin, and WT-1) in cultured podocytes. Finally, we confirmed that BD4 reduces proteinuria and improves kidney injury in HIV-1 transgenic mice, a model for HIV-associated nephropathy (HIVAN). Mice treated with BD4 did not develop any obvious toxicity or side effect. Our data suggest that BD4 is a novel RARα agonist, which could be used as a potential therapy for patients with kidney disease such as HIVAN.

Therapy-related acute promyelocytic leukemia: observations relating to APL pathogenesis and therapy

Therapy-related acute promyelocytic leukemia (t-APL) is a well-recognized form of APL for which the underlying etiology has been well characterized. The pathogenesis of de novo (dn-APL) remains unknown; but epidemiologic studies have consistently identified increased body mass index (BMI), younger age, and ethnicity as possible risk factors. We analyzed demographics, clinical features, and treatment responses in a contemporary series of 64 patients treated with all-trans-retinoic acid and anthracycline-based therapy to assess for differences in these two etiologically distinct patient groups. Compared with patients with t-APL (n = 11), those with dn-APL (n = 53) had a greater median BMI (31.33 vs. 28.48), incidence of obesity (60.4% vs. 27.3%) (P = 0.04), and history of hyperlipidemia (45.3% vs. 18.2%) (P = 0.01). Fewer t-APL than dn-APL patients achieved complete remission at 63.6% vs. 92.5% respectively (P = 0.008). This was the result of a higher induction mortality rate of 36.4% vs. 7.5% respectively (P = 0.008). No cases of leukemic resistance were seen in either group. Overall survival (OS) was inferior in t-APL compared with dn-APL at 51% vs. 84%, respectively (P < 0.005), primarily as a result of higher induction mortality. Relapse occurred in nine patients (16.1%) overall, but no relapses occurred in the t-APL cohort. Our observations provide further support for the hypothesis that abnormalities in lipid homeostasis may in some way be of pathogenic importance in dn-APL. Therapy-related APL is sensitive to standard therapy with no cases of resistance or relapse seen. The inferior OS of the t-APL was due to induction mortality, possibly reflecting prior therapy.

Increased BMI correlates with higher risk of disease relapse and differentiation syndrome in patients with acute promyelocytic leukemia treated with the AIDA protocols

We investigated whether body mass index (BMI) correlates with distinct outcomes in newly diagnosed acute promyelocytic leukemia (APL). The study population included 144 patients with newly diagnosed and genetically confirmed APL consecutively treated at a single institution. All patients received All-trans retinoic acid and idarubicin according to the GIMEMA protocols AIDA-0493 and AIDA-2000. Outcome estimates according to the BMI were carried out together with multivariable analysis for the risk of relapse and differentiation syndrome. Fifty-four (37.5%) were under/normal weight (BMI < 25), whereas 90 (62.5%) patients were overweight/obese (BMI ≥ 25). An increased BMI was associated with older age (P < .0001) and male sex (P = .02). BMI was the most powerful predictor of differentiation syndrome in multivariable analysis (odds ratio = 7.24; 95% CI, 1.50-34; P = .014). After a median follow-up of 6 years, the estimated cumulative incidence of relapse at 5 years was 31.6% (95% CI, 22.7%-43.8%) in overweight/obese and 11.2% (95% CI, 5.3%-23.8%) in underweight/normal weight patients (P = .029). Multivariable analysis showed that BMI was an independent predictor of relapse (hazard ratio = 2.45, 95% CI, 1.00-5.99, in overweight/obese vs under/normal weight patients, P = .049). An increased BMI at diagnosis is associated with a higher risk of developing differentiation syndrome and disease relapse in APL patients treated with AIDA protocols.

Differentiation syndrome in promyelocytic leukemia: clinical presentation, pathogenesis and treatment

Differentiation syndrome (DS) represents a life-threatening complication in patients with acute promyelocytic leukemia (APL) undergoing induction therapy with all-trans retinoic acid (ATRA) or arsenic trioxide (ATO). It affected about 20–25% of all patients and so far there are no definitive diagnostic criteria. Clinically, DS is characterized by weight gain, fever not attributable to infection, respiratory distress, cardiac involvement, hypotension, and/or acute renal failure. At the histological point of view, there is an extensive interstitial and intra-alveolar pulmonary infiltration by maturing myeloid cells, endothelial cell damage, intra-alveolar edema, inter-alveolar hemorrhage, and fibrinous exsudates. DS pathogenesis is not completely understood, but it is believed that an excessive inflammatory response is the main phenomenon involved, which results in increased production of chemokines and expression of adhesion molecules on APL cells. Due to the high morbidity and mortality associated with DS, its recognition and the prompt initiation of the treatment is of utmost importance. Dexamethasone is considered the mainstay of treatment of DS, and the recommended dose is 10 mg twice daily by intravenous route until resolution of DS. In severe cases (respiratory or acute renal failure) it is recommended the discontinuation of ATRA or ATO until recovery.

Treatment of Acute Promyelocytic Leukemia with AIDA Based Regimen. Update of a Tunisian Single Center Study

In Tunisia, the ATRA era began in 1998 with the use, consecutively, of two regimens combining ATRA and an anthracycline with cytarabine (APL93), and without cytarabine (LPA99). From 2004, 51 patients with confirmed APL either by t(15;17) or PML/RARA were treated according to the PETHEMA LPA 99 trial. Forty three patients achieved CR (86%). The remaining seven patients had early death (one died before treatment onset): four caused by differentiation syndrome (DS) and three died from central nervous system hemorrhage. Multivariate analysis revealed that female gender (P=0.045), baseline WBC> 10 G/L (P=0.041) and serum creatinine > 1.4mg/dl (P=0.021) were predictive of mortality during induction. DS was observed in 16 patients (32%) after a median onset time of 15 days from treatment onset (range, 2-29). Body mass index ≥ 30 (P=0.01) remained independent predictor of DS. Occurrence of hypertensive peaks significantly predicted occurrence of DS (P=0.011) and was significantly associated with high BMI (p=0.003). With a median follow-up of 50 months, 5 year cumulative incidence of relapse, event free and overall survival were 4.7%, 74% and 78%, respectively.

Treatment of acute promyelocytic leukemia with high white cell blood counts

Acute promyelocytic leukemia (APL) with WBC above 10 G/L has long been considered, even in the all-trans retinoic acid (ATRA) era, to carry a relatively poor prognosis (compared to APL with WBC below 10 G/L), due to increased early mortality and relapse. However, early deaths can to a large extent be avoided if specific measures are rapidly instigated, including prompt referral to a specialized center, immediate onset of ATRA and chemotherapy, treatment of coagulopathy with adequate platelet transfusional support, and prevention and management of differentiation syndrome. Strategies to reduce relapse rate include chemotherapy reinforcement with cytarabine and/or arsenic trioxide during consolidation, prolonged maintenance treatment, especially with ATRA and low dose chemotherapy, and possibly, although this is debated, intrathecal prophylaxis to prevent central nervous system relapse. By applying those measures, outcomes of patients with high risk APL have considerably improved, and have become in many studies almost similar to those of standard risk APL patients.

Prognostic value of FLT3 mutations in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline monochemotherapy

BACKGROUND

Fms-like tyrosine kinase-3 (FLT3) gene mutations are frequent in acute promyelocytic leukemia but their prognostic value is not well established.

DESIGN AND METHODS

We evaluated FLT3-internal tandem duplication and FLT3-D835 mutations in patients treated with all-trans retinoic acid and anthracycline-based chemotherapy enrolled in two subsequent trials of the Programa de Estudio y Tratamiento de las Hemopatías Malignas (PETHEMA) and Hemato-Oncologie voor Volwassenen Nederland (HOVON) groups between 1996 and 2005.

RESULTS

FLT3-internal tandem duplication and FLT3-D835 mutation status was available for 306 (41%) and 213 (29%) patients, respectively. Sixty-eight (22%) and 20 (9%) patients had internal tandem duplication and D835 mutations, respectively. Internal tandem duplication was correlated with higher white blood cell and blast counts, lactate dehydrogenase, relapse-risk score, fever, hemorrhage, coagulopathy, BCR3 isoform, M3 variant subtype, and expression of CD2, CD34, human leukocyte antigen-DR, and CD11b surface antigens. The FLT3-D835 mutation was not significantly associated with any clinical or biological characteristic. Univariate analysis showed higher relapse and lower survival rates in patients with a FLT3-internal tandem duplication, while no impact was observed in relation to FLT3-D835. The prognostic value of the FLT3-internal tandem duplication was not retained in the multivariate analysis.

CONCLUSIONS

FLT3-internal tandem duplication mutations are associated with several hematologic features in acute promyelocytic leukemia, in particular with high white blood cell counts, but we were unable to demonstrate an independent prognostic value in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline-based regimens.

Continuing high early death rate in acute promyelocytic leukemia: a population-based report from the Swedish Adult Acute Leukemia Registry

Our knowledge about acute promyelocytic leukemia (APL) patients is mainly based on data from clinical trials, whereas population-based information is scarce. We studied APL patients diagnosed between 1997 and 2006 in the population-based Swedish Adult Acute Leukemia Registry. Of a total of 3897 acute leukemia cases, 3205 (82%) had non-APL acute myeloid leukemia (AML) and 105 (2.7%) had APL. The incidence of APL was 0.145 per 100,000 inhabitants per year. The median age at the time of diagnosis was 54 years; 62% were female and 38% male. Among younger APL patients, female sex predominated (89% of patients <40 years). Of the 105 APL patients, 30 (29%) died within 30 days (that is, early death (ED)) (median 4 days) and 28 (26%) within 14 days from diagnosis. In all, 41% of the EDs were due to hemorrhage; 35% of ED patients never received all-trans-retinoic acid treatment. ED rates increased with age but more clearly with poor performance status. ED was also associated with high white blood cells, lactate dehydrogenase, creatinine, C-reactive protein and low platelet count. Of non-ED patients, 97% achieved complete remission of which 16% subsequently relapsed. In total, 62% are still alive at 6.4 years median follow-up. We conclude that ED rates remain very high in an unselected APL population.

Differentiation syndrome in patients with acute promyelocytic leukemia

OBJECTIVE

To review the pathophysiology, risk factors, and management of differentiation syndrome (DS) associated with acute promyelocytic leukemia (APL).

DATA SOURCE

A MEDLINE search was conducted (1977-November 2010) using the terms APL, DS, all-trans retinoic acid (ATRA), retinoic acid syndrome, and arsenic trioxide (ATO).

METHODS OF STUDY SELECTION

English articles identified from the MEDLINE search were evaluated.

DATA EXTRACTION AND SYNTHESIS

With ATRA, ATO, and chemotherapy, a complete remission is achievable for most newly diagnosed APL patients. However, treatment with the differentiating agents, ATRA and ATO, can lead to the development of DS. Signs and symptoms of this syndrome include hyperleukocytosis and cardiorespiratory compromise. Severe complications can develop, if DS is not recognized early and treated promptly with corticosteroids. In addition, patients with a high white blood cell count at diagnosis may benefit from prophylactic steroids.

CONCLUSIONS

Early recognition and prompt initiation of corticosteroids are key factors in the management of DS. Healthcare professionals need to be familiar with this complication which can arise from differentiation agents.

A novel NUP98/RARG gene fusion in acute myeloid leukemia resembling acute promyelocytic leukemia

Chromosomal translocations in hematological malignancies often result in novel fusion chimeric genes. We report a case of acute myeloid leukemia with a clonal translocation t(11;12)(p15;q13) displaying morphologic and immunophenotypic features resembling the classical hypergranular subtype of acute promyelocytic leukemia. The gene fused to NUP98 (nucleoporin 98) was detected by comparative genomic hybridization array as the retinoid acid receptor gamma gene (RARG). The involvement of RARG in a chimeric fusion transcript has not been reported previously in human leukemia.

Clinical significance of CD56 expression in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline-based regimens

The expression of CD56 antigen in acute promyelocytic leukemia (APL) blasts has been associated with short remission duration and extramedullary relapse. We investigated the clinical significance of CD56 expression in a large series of patients with APL treated with all-trans retinoic acid and anthracycline-based regimens. Between 1996 and 2009, 651 APL patients with available data on CD56 expression were included in 3 subsequent trials (PETHEMA LPA96 and LPA99 and PETHEMA/HOVON LPA2005). Seventy-two patients (11%) were CD56(+) (expression of CD56 in ≥ 20% leukemic promyelocytes). CD56(+) APL was significantly associated with high white blood cell counts; low albumin levels; BCR3 isoform; and the coexpression of CD2, CD34, CD7, HLA-DR, CD15, and CD117 antigens. For CD56(+) APL, the 5-year relapse rate was 22%, compared with a 10% relapse rate for CD56(-) APL (P = .006). In the multivariate analysis, CD56 expression retained the statistical significance together with the relapse-risk score. CD56(+) APL also showed a greater risk of extramedullary relapse (P < .001). In summary, CD56 expression is associated with the coexpression of immaturity-associated and T-cell antigens and is an independent adverse prognostic factor for relapse in patients with APL treated with all-trans-retinoic acid plus idarubicin-derived regimens. This marker may be considered for implementing risk-adapted therapeutic strategies in APL. The LPA2005 trial is registered at http://www.clinicaltrials.gov as NCT00408278.

Advances in understanding the pulmonary infiltration in acute promyelocytic leukaemia

In acute promyelocytic leukaemia (APL), differentiation therapy can be complicated by the development of a differentiation syndrome (DS). Pulmonary infiltration of differentiating leukaemic cells is a key event in the development of DS. Several mediators have been identified that may promote migration and extravasation of differentiating APL cells from the bloodstream into the tissue. Adhesion of APL cells to each other and to the endothelium is induced by upregulation of the expression of adhesion molecules and constitutively active β2-integrins during differentiation therapy. The expression of chemokines and their receptors is significantly upregulated as well. Pulmonary chemokine production can trigger transendothelial migration of differentiating APL cells from the bloodstream into the underlying tissue (initiation phase of DS). Massive production of chemokines by infiltrated APL cells can further enhance transendothelial migration of differentiating APL cells, causing an uncontrollable hyperinflammatory reaction in the lung (aggravation phase), which is not efficiently switched-off by corticosteroids.

Treatment of acute promyelocytic leukemia with PETHEMA LPA 99 protocol: a Tunisian single center experience

Acute promyelocytic leukemia (APL) has now become the most curable of all subtypes of acute myeloid leukemia. A cure rate of 75-80% can be anticipated with a combination of all-trans retinoic acid (ATRA) and anthracyclines. In Tunisia, the ATRA era began in 1998 with the use, consecutively, of two regimens of a combination of ATRA with anthracycline and cytarabine (APL93), and without cytarabine (LPA99). From 2004, 39 patients with confirmed APL either by t(15;17) or PML/RARA were treated by the PETHEMA LPA 99 trial. The rationale of this protocol by avoiding cytarabine is to reduce death in complete remission (CR) without increasing the incidence of relapse. Thirty-three patients achieved CR (84.6%). The remaining six patients were considered as failure due to early death: three caused by differentiation syndrome (DS) and three died from central nervous system hemorrhage. Baseline blood cell count (WBC) >10 x 10(9)/l (P=0.26) and creatinine >1.4 mg/dl (P=0.42) were not predictive of mortality. DS was observed in 11 patients (30.5%) with a median onset time of 12 days (range: 3-23 days) and median WBC of 29 x 10(9)/L (range: 1.2 x 10(9)-82.7 x 10(9)/l). DS was severe in seven cases, moderate in four, and fatal in three cases. Body mass index > or =30 (P=0.044) and baseline WBC > or =20 x 10(9)/l (P=0.025) are independent predictors of DS. The median follow-up of this study is 36 months. Thirty patients are alive in continuous complete remission; two patients died in CR from septic shock and secondary myelodysplastic syndrome respectively; one patient died 47 months after achieving two relapses. Event free survival from diagnosis was 80% and overall survival was 82%. Our results are quite acceptable and can be improved by reducing mortality rate.

Proteomic cell surface phenotyping of differentiating acute myeloid leukemia cells

Immunophenotyping by flow cytometry or immunohistochemistry is a clinical standard procedure for diagnosis, classification, and monitoring of hematologic malignancies. Antibody-based cell surface phenotyping is commonly limited to cell surface proteins for which specific antibodies are available and the number of parallel measurements is limited. The resulting limited knowledge about cell surface protein markers hampers early clinical diagnosis and subclassification of hematologic malignancies. Here, we describe the mass spectrometry based phenotyping of 2 all-trans retinoic acid treated acute myeloid leukemia model systems at an unprecedented level to a depth of more than 500 membrane proteins, including 137 bona fide cell surface exposed CD proteins. This extensive view of the leukemia surface proteome was achieved by developing and applying new implementations of the Cell Surface Capturing (CSC) technology. Bioinformatic and hierarchical cluster analysis showed that the applied strategy reliably revealed known differentiation-induced abundance changes of cell surface proteins in HL60 and NB4 cells and it also identified cell surface proteins with very little prior information. The extensive and quantitative analysis of the cell surface protein landscape from a systems biology perspective will be most useful in the clinic for the improved subclassification of hematologic malignancies and the identification of new drug targets.

Does microgranular variant morphology of acute promyelocytic leukemia independently predict a less favorable outcome compared with classical M3 APL? A joint study of the North American Intergroup and the PETHEMA Group

Few studies have examined the outcome of large numbers of patients with the microgranular variant (M3V) of acute promyelocytic leukemia (APL) in the all-trans retinoic acid era. Here, the outcome of 155 patients treated with all-trans retinoic acid-based therapy on 3 clinical trials, North American Intergroup protocol I0129 and Programa para el Estudio de la Terapéutica en Hemopatía Maligna protocols LPA96 and LPA99, are reported. The complete remission rate for all 155 patients was 82%, compared with 89% for 748 patients with classical M3 disease. The incidence of the APL differentiation syndrome was 26%, compared with 25% for classical M3 patients, and the early death rate was 13.6% compared with 8.4% for patients with classical M3 morphology. With a median follow-up time among survivors of 7.6 years (range 3.6-14.5), the 5-year overall survival, disease-free survival, and cumulative incidence of relapse for patients with M3V were 70%, 73%, and 24%, respectively. With a median follow-up time among survivors of 7.6 years (range 0.6-14.3), the 5-year overall survival, disease-free survival, and cumulative incidence of relapse among patients with classical M3 morphology were 80% (P = .006 compared with M3V), 81% (P = .07), and 15% (P = .005), respectively. When outcomes were adjusted for the white blood cell count or the relapse risk score, none of these outcomes were significantly different between patients with M3V and classical M3 APL.

Inhibition of the redox function of APE1/Ref-1 in myeloid leukemia cell lines results in a hypersensitive response to retinoic acid-induced differentiation and apoptosis

OBJECTIVE

The standard of care for promyelocytic leukemia includes use of the differentiating agent all-trans retinoic acid (RA) and chemotherapy. RA induces cell differentiation through retinoic acid receptor (RAR) transcription factors. Because redox mechanisms influence how readily transcription factors bind to DNA response elements (RARE), the impact of small molecule (E3330) inhibition of the redox regulatory protein, apurinic-apyrimidinic endonuclease/redox effector factor (APE1/Ref-1) on RAR DNA binding and function in RA-induced myeloid leukemia cell differentiation and apoptosis was investigated.

MATERIALS AND METHODS

The redox function of APE1 was studied using the small molecule inhibitor E3330 in HL-60 and PLB acute myeloid leukemia cells. Electrophoretic mobility shift assays were employed to determine effect of inhibitor on APE1/Ref-1 redox signaling function. Trypan blue assays, Annexin-V/propidium iodide and CD11b staining, and real-time polymerase chain reaction analyses were employed to determine survival, apoptosis, and differentiation status of cells in culture.

RESULTS

RARα binds to its RARE in a redox-dependent manner mediated by APE1/Ref-1 redox regulation. Redox-dependent RAR-RARE binding is blocked by E3330, a small molecule redox inhibitor of APE1/Ref-1. Combination treatment of RA + E3330 results in a profound hypersensitivity of myeloid leukemia cells to RA-induced differentiation and apoptosis. Additionally, redox inhibition by E3330 results in enhanced RAR target gene, BLR-1, expression in myeloid leukemia cells.

CONCLUSIONS

The redox function of APE1/Ref-1 regulates RAR binding to its DNA RAREs influencing the response of myeloid leukemia cells to RA-induced differentiation. Targeting of APE1/Ref-1 redox function may allow manipulation of the retinoid response with therapeutic implications.

Open issues on bleeding and thrombosis in acute promyelocytic leukemia

Acute promyelocytic leukemia (APL) is a distinct subtype of acute myeloid leukemia characterized by a specific genetic alteration, affecting the retinoic acid receptor-alpha (RAR-alpha), and leading to the accumulation of the promyelocytic blasts in the bone marrow and blood which is frequently associated with a life-threatening consumptive coagulopathy. The body of biological information on APL establishes this leukemia as a unique entity that has to be promptly recognized to counteract the coagulopathy, especially in light of its striking response to treatment with all-trans retinoic acid. In fact, the current standard for induction therapy results in extremely high antileukemic efficacy, achieving 90 to 95% complete remission rate. However, while primary leukemia resistance has virtually disappeared as a cause of remission induction failure, death due to hemorrhage remains the major problem during the early treatment phase. As a part of the clotting activation commonly present in APL, thrombosis is a less recognized and probably underestimated life-threatening manifestation in patients with this disease. In addition to reviewing the available data on the incidence, outcome and prognostic factors of bleeding and thrombosis in APL, we discuss the current consensus and controversies on the most appropriate management of these complications.

Enhanced growth inhibition of metastatic lung tumors by intravenous injection of ATRA-cationic liposome/IL-12 pDNA complexes in mice

Interleukin 12 (IL-12) is a proinflammatory cytokine with antitumor activity. All-trans-retinoic acid (ATRA) exerts antitumor effects by regulating a variety of gene expressions, including tumor necrosis factor receptor 1 (TNFR1), increases the number of TNFR1 and potentiates TNF-alpha-induced apoptosis in cancer cells. In this study, ATRA-incorporated cationic liposome (ATRA-cationic liposome)/IL-12 plasmid DNA (pDNA) complexes were prepared to improve therapeutic efficacy of cationic liposome/IL-12 pDNA complexes in a mouse model of metastatic lung tumor after intravenous injection. IL-12 production in lungs by ATRA-cationic liposome/IL-12 pDNA complexes was comparable with that by cationic liposome/IL-12 pDNA complexes. The number of metastatic tumor cells (colon26/Luc) was quantitatively evaluated by measuring luciferase activity. ATRA-cationic liposome/IL-12 pDNA complexes reduced the number of colon26/Luc cells and tumor nodules in lungs. ATRA-cationic liposome/IL-12 pDNA complexes significantly prolonged the survival time of mice, whereas cationic liposome/IL-12 pDNA only slightly prolonged it. ATRA-cationic liposome/IL-12 pDNA complexes increased the TNFR1 mRNA upregulation and the number of apoptotic cells in the lung. Moreover, reduced serum alanine transaminase (ALT) and aspartate transaminase (AST) activities were observed in mice treated with ATRA-cationic liposome/IL-12 pDNA complexes. These results suggest that intravenous injection of ATRA-cationic liposome/IL-12 pDNA complexes is an effective method for the treatment of lung metastasis in mice.

Risk-adapted treatment of acute promyelocytic leukemia based on all-trans retinoic acid and anthracycline with addition of cytarabine in consolidation therapy for high-risk patients: further improvements in treatment outcome

A risk-adapted strategy based on all-trans retinoic acid (ATRA) and anthracycline monochemotherapy (PETHEMA LPA99 trial) has demonstrated a high antileukemic efficacy in acute promyelocytic leukemia. We designed a new trial (LPA2005) with the objective of achieving stepwise improvements in outcome. Between July 2005 and April 2009, low- and intermediate-risk patients (leukocytes < 10 x 10(9)/L) received a reduced dose of mitoxantrone for the second consolidation course, whereas high- risk patients younger than 60 years of age received cytarabine combined with ATRA and idarubicin in the first and third consolidation courses. Of 372 patients attaining complete remission after ATRA plus idarubicin (92.5%), 368 proceeded to consolidation therapy. For low- and intermediate-risk patients, duration of neutropenia and thrombocytopenia and hospital stay were significantly reduced without sacrificing antileukemic efficacy, compared with the previous LPA99 trial. For high-risk patients, the 3-year relapse rate was significantly lower in the LPA2005 trial (11%) than in the LPA99 (26%; P = .03). Overall disease-free survival was also better in the LPA2005 trial (P = .04). In conclusion, the lower dose of mitoxantrone resulted in a significant reduction of toxicity and hospital stay while maintaining the antileukemic activity, and the combination of ATRA, idarubicin, and cytarabine for high-risk acute promyelocytic leukemia significantly reduced the relapse rate in this setting. Registered at http://www.clinicaltrials.gov as NCT00408278.

Recurrent differentiation syndrome or septic shock? Unresolved dilemma in a patient with acute promyelocytic leukemia

Differentiation syndrome (DS) is a life-threatening complication observed in patients with acute promyelocytic leukemia (APL) receiving induction therapy with all-trans-retinoic acid (ATRA). A bimodal incidence of DS has been observed, with a majority of cases occurring during the first week of ATRA treatment ("early" DS), but a substantial number of cases occurring during the third or even fourth week of ATRA treatment ("late" DS). However, to our knowledge occurrence of both early and late DS in the same patient has not been reported. We report an APL patient treated with the AIDA regimen, who experienced both early and late DS, a situation where differential diagnosis was difficult.

Exacerbation of anthracycline-induced early chronic cardiomyopathy with ATRA: role of B-type natriuretic peptide as an indicator of cardiac dysfunction

Cardiac disease is a significant complication of childhood oncologic therapy. We report the case of a 14-year-old female with acute promyelocytic leukemia who developed symptomatic cardiomyopathy only 4 months into treatment with a combination of daunomycin and all-trans retinoic acid (ATRA). Despite cessation of daunomycin, she demonstrated fluctuating systolic function in relation to ATRA administration. Improvement and deterioration in systolic function on echocardiogram and serum B-natriuretic peptide levels were seen while receiving ATRA 1 week on and 1 week off, respectively, during the maintenance phase of therapy.

How I treat acute promyelocytic leukemia

Acute promyelocytic leukemia is the first malignant disease highly curable with targeted therapy directed at a unique molecular abnormality. The characteristic bleeding diathesis is the most notorious manifestation of the disease, which historically has accounted for a high mortality rate during induction. Acute promyelocytic leukemia is one of the few hematologic diseases that must be recognized under the microscope by the practicing hematologist because early institution of all-trans retinoic acid (ATRA) at the first suspicion of the disease before confirmation of the diagnosis and aggressive blood product support are critical to reduce early mortality. ATRA plus anthracycline-based chemotherapy for induction and consolidation followed by maintenance ATRA with low-dose chemotherapy is currently the standard of care. However, the combination of ATRA and arsenic trioxide, with minimal chemotherapy to control leukocytosis, is very effective therapy for newly diagnosed patients. This combination may replace conventional approaches for most, if not all, patients in the very near future. Acute promyelocytic leukemia should be considered in any patient with newly diagnosed acute myeloid leukemia because the treatment is urgent and different from all other subtypes.

DNA vaccination with all-trans retinoic acid treatment induces long-term survival and elicits specific immune responses requiring CD4+ and CD8+ T-cell activation in an acute promyelocytic leukemia mouse model

DNA vaccination and all-trans retinoic acid (ATRA) result in a survival advantage in a mouse model of acute promyelocytic leukemia (APL). Depletion of CD4(+) or CD8(+) cells abolished this effect. CD4(+) depletions of long-term survivors resulted in relapse and death within 3 months, thus demonstrating the need of both CD4(+) and CD8(+) subsets for the generation of DNA-driven antileukemic immune responses and underscoring a crucial role of CD4(+) cells in the maintenance of durable remissions. Degranulation and cytotoxic carboxyfluorescein diacetate succinimidyl ester-based assays showed major histocompatibility complex-restricted APL-specific T cell-mediated immune responses. Sorted APL-specific CD8(+)CD107a(+) T cells showed an increase of antileukemic activity. Effectors from ATRA + DNA-treated mice were shown to secrete interferon-gamma when stimulated with either APL cells or peptides from the promyelocytic leukemia-RARalpha vaccine-derived sequences as detected by ELISpot assays. Our results demonstrate that DNA vaccination with ATRA confers the effective boosting of interferon-gamma-producing and cytotoxic T cells in the leukemic mice.

Chemokine induction by all-trans retinoic acid and arsenic trioxide in acute promyelocytic leukemia: triggering the differentiation syndrome

In acute promyelocytic leukemia (APL), differentiation therapy with all-trans retinoic acid (ATRA) and/or arsenic trioxide can induce a differentiation syndrome (DS) with massive pulmonary infiltration of differentiating leukemic cells. Because chemokines are implicated in migration and extravasation of leukemic cells, chemokines might play a role in DS. ATRA stimulation of the APL cell line NB4 induced expression of multiple CC-chemokines (CCLs) and their receptors (> 19-fold), resulting in increased chemokine levels and chemotaxis. Induction of CCL2 and CCL24 was directly mediated by ligand-activated retinoic acid receptors. In primary leukemia cells derived from APL patients at diagnosis, ATRA induced chemokine production as well. Furthermore, in plasma of an APL patient with DS, we observed chemokine induction, suggesting that chemokines might be important in DS. Dexamethasone, which efficiently reduces pulmonary chemokine production, did not inhibit chemokine induction in APL cells. Finally, chemokine production was also induced by arsenic trioxide as single agent or in combination with ATRA. We propose that differentiation therapy may induce chemokine production in the lung and in APL cells, which both trigger migration of leukemic cells. Because dexamethasone does not efficiently reduce leukemic chemokine production, pulmonary infiltration of leukemic cells may induce an uncontrollable hyperinflammatory reaction in the lung.

High body mass index is an independent predictor of differentiation syndrome in patients with acute promyelocytic leukemia

Increased BMI has been correlated to an increased incidence of APL, but not to the occurrence of differentiation syndrome (DS) in APL. We consecutively treated 39 APL patients with ATRA and idarubicin (according to PETHEMA regimen). Median age was 26 years. Forty-one percent patients were classified as intermediate risk, and 59% as high risk according to Sanz's score. Thirty-three patients (85%) reached CR. Eleven of the 36 patients evaluable for DS (30.5%) developed this syndrome (severe in 7 cases, moderate in 4, and fatal in 3 cases) within a median of 12 days (range 3-23) of ATRA onset. Six of the 9 (66.6%) patients with BMI>or=30 developed DS vs. 5 of 27 (18.5%) with BMI<30 (p=0.012). Other predictors of DS in univariate analysis were: age>or=40 year (p=0.033), baseline WBC>or=20 x 10(9)/l (p=0.003), and creatinine>1.4 mg/dl (p=0.009). In multivariate analysis, BMI>or=30 remained an independent predictor of DS in addition to baseline WBC>or=20 x 10(9)/l.

High dose ara-C in the treatment of newly diagnosed acute promyelocytic leukemia: long-term results of the German AMLCG

The objective of this study for newly diagnosed acute promyelocytic leukemia (APL) was to evaluate the efficacy of an intensified double induction chemotherapy including high dose ara-C (HD) and all-trans retinoic acid (ATRA) followed by consolidation and 3 years maintenance therapy. In contrast to APL studies stratifying therapy according to pretreatment white blood cell (WBC) count < and > or =10 x 10(9)/l (low/intermediate and high risk according to the Sanz score), our patients received uniform therapy. From 1994 to 2005, 142 patients (age, 16-60 years) were enrolled. In the low/intermediate (n=105) vs high (n=37) WBC group, the rates of complete remission were 95.2 vs 83.8%, of induction death were 4.8 vs 16.2% (P=0.05) and of molecular remission were 87.5 vs 91.3% (P=1). Long-term overall survival was 84.4 vs 73.0% (P=0.12), event free survival was 78.3 vs 67.3% (P=0.11), relapse free survival was 82.1 vs 80.0% (P=0.83) and the cumulative incidence of relapse was 7.4 vs 11.4% (P=0.46). No relapse or death occurred after 4.7 years. ATRA and intensified chemotherapy including HD ara-C followed by prolonged maintenance therapy reduced the relapse risk in high risk patients. Pretreatment WBC count > or =10 x 10(9)/l count was no relevant prognostic factor for relapse.

Combined low doses of PPARgamma and RXR ligands trigger an intrinsic apoptotic pathway in human breast cancer cells

Ligand activation of peroxisome proliferator-activated receptor (PPAR)gamma and retinoid X receptor (RXR) induces antitumor effects in cancer. We evaluated the ability of combined treatment with nanomolar levels of the PPARgamma ligand rosiglitazone (BRL) and the RXR ligand 9-cis-retinoic acid (9RA) to promote antiproliferative effects in breast cancer cells. BRL and 9RA in combination strongly inhibit of cell viability in MCF-7, MCF-7TR1, SKBR-3, and T-47D breast cancer cells, whereas MCF-10 normal breast epithelial cells are unaffected. In MCF-7 cells, combined treatment with BRL and 9RA up-regulated mRNA and protein levels of both the tumor suppressor p53 and its effector p21(WAF1/Cip1). Functional experiments indicate that the nuclear factor-kappaB site in the p53 promoter is required for the transcriptional response to BRL plus 9RA. We observed that the intrinsic apoptotic pathway in MCF-7 cells displays an ordinated sequence of events, including disruption of mitochondrial membrane potential, release of cytochrome c, strong caspase 9 activation, and, finally, DNA fragmentation. An expression vector for p53 antisense abrogated the biological effect of both ligands, which implicates involvement of p53 in PPARgamma/RXR-dependent activity in all of the human breast malignant cell lines tested. Taken together, our results suggest that multidrug regimens including a combination of PPARgamma and RXR ligands may provide a therapeutic advantage in breast cancer treatment.

Recent Publications on Medications and Pharmacy

Hospital Pharmacy presents this feature to keep pharmacists abreast of new publications in the medical/pharmacy literature. Articles of interest regarding a broad scope of topics are abstracted monthly.