t(4;11)(q21;p15) translocation involving NUP98 and RAP1GDS1 genes: characterization of a new subset of T acute lymphoblastic leukaemia

Two cases of T acute lymphoblastic leukaemia (T-ALL) with an identical t(4;11)(q21;p15) translocation were identified within a prospective study on the biological and clinical features of adult ALL patients enrolled into the therapeutic protocol ALL0496 of the GIMEMA Italian Group. In both cases, the molecular characterization showed an involvement of the NUP98 gene on 11p15 which rearranges with the RAP1GDS1 gene on 4q21. The morphological and immunological features of the leukaemic cells, as well as the clinical behaviour and response to induction therapy, were the same in both patients. Based on the available data, the t(4;11)(q21;p15) translocation involving the NUP98-RAP1GDS1 fusion gene emerges as a new highly specific genetic abnormality that characterizes a subset of T-ALL.

[Otoneurological findings in a case of congenital central hypoventilation syndrome (Ondine's curse)]

The authors report a case of congenital central hypoventilation syndrome (CCHS) studied from the otoneurological point of view. Emphasis is placed on the numerous alterations in the electronystagmograph and auditory potentials. The results obtained confirm the hypothesis that such patients are subject to CNS alterations, suggesting that the disease pathogenesis derives from an alteration in the mechanism of central chemoreceptor stimuli integration.

Scalarane and homoscalarane compounds from the nudibranchs Glossodoris sedna and Glossodoris dalli: chemical and biological properties

A series of homoscalarane and scalarane compounds (2-7) have been isolated from two distinct species of Pacific Glossodoris nudibranchs. The structure and elucidation of the relative stereochemistry of the new metabolites 2 and 3 were obtained by spectroscopic methods. Compound 2 was ichthyotoxic at 0.1 ppm against Gambusia affinis and showed moderate activity (IC(50) 18 microM) to inhibit mammalian phospholipase A(2).

HLA class I in acute promyelocytic leukemia (APL): possible correlation with clinical outcome

The majority of patients with acute promyelocytic leukemia (APL) possess either a bcr1 or a bcr3 type fusion between PML and RARalpha genes. The junction sequences may possibly be a target for immune response and influence susceptibility to the disease. In this case, HLA class I allele frequencies would be different between bcr1 and bcr3 patients. To test this hypothesis, we typed 102 APL patients for HLA-A, -B and -Cw alleles. The A*1, A*30, B*51, B*41, Cw*0602, and Cw*1701 alleles showed a different distribution between bcr1 and bcr3 patients, but in no case was this statistically significant after correction for the number of comparisons or was confirmed in an independent panel. Moreover, no difference was detected between bcr1 and bcr3 when HLA alleles were grouped according to their peptide binding specificities. Comparing HLA frequencies, clinical features at diagnosis and clinical outcome of the 64 patients homogeneously treated with all-trans retinoic acid and idarubicin (AIDA protocol) we observed a statistically significant association between HLA-B*13 and risk of relapse by univariate and multivariate regression analysis. Should this finding be confirmed in larger future studies, this observation would be of outmost importance in identifying patients at high risk of relapse in which more aggressive consolidation therapies should be used.

A prospective study of residual-disease monitoring of the ALL1/AF4 transcript in patients with t(4;11) acute lymphoblastic leukemia

Twenty-five patients (22 adults and 3 infants) with ALL1/AF4-positive acute lymphoblastic leukemia (ALL) were prospectively monitored by reverse transcriptase-polymerase chain reaction (RT-PCR) between January 1992 and July 1999. After high-dose induction and consolidation chemotherapy without bone marrow transplantation, all patients had a complete hematologic remission. Using nested RT-PCR (sensitivity 10(-4)), we observed conversion to PCR negativity in 11 (44%) of the patients. Thirteen of the 14 patients who did not have a molecular remission had a relapse at a median time of 4 months (range, 1 - 20 months). Of the 11 patients who had a conversion to PCR negativity, 5 reconverted to PCR positivity within 1 to 14 months. These 5 patients all progressed to hematologic relapse after 2, 3, 4, 4, and 7 months, respectively. Of the remaining 6 patients, 4 are in persistent hematologic and molecular remission at 12, 14, 88, and 96 months, whereas 2 are early in their follow-up. Actuarial probabilities of relapse and overall survival were 100% and 0% at 14 and 24 months and 67% and 43% at 96 and 100 months, respectively, in patients who had persistent RT-PCR positivity and in those who had a molecular remission. For both relapse and survival, the differences observed between the two groups were significant (P =.003 and P <.005, respectively). This study, which represents the first prospective analysis of residual-disease monitoring carried out in a substantial series of patients with t(4;11)-positive ALL, emphasizes the clinical relevance of RT-PCR-based methods to monitor minimal residual disease in this leukemia subset. (Blood. 2000;95:96-101)

New scalaranes from the nudibranch Glossodoris atromarginata and its sponge prey

Two new scalaranes (1 and 2) have been isolated from the dorid nudibranch Glossodoris atromarginataand its prey. The structures were deteremined by spectral techniques and confirmed by chemical methods. Compounds 1 and 3 showed selective cytotoxic activity against human thyroid carcinoma.

Out-patient management of acute myeloid leukemia after consolidation chemotherapy. Role of a hematologic emergency unit

BACKGROUND AND OBJECTIVE

Increasing attention to quality of life and to health care costs has recently induced several cancer centers to change in-patient management into an out-patient setting even during high risk phases of disease. The aim of this prospective study was to evaluate feasibility and safety, as well as clinical characteristics, of out-hospital management of AML patients during their post-consolidation phase.

DESIGN AND METHODS

All patients who were treated over a three year period by the three following protocols were included in the study: AML10 EORTC/GIMEMA for patients with AML, except for APL, aged </= 60 years; AML 13 EORTC/GIMEMA, for patients with AML, except for APL, aged >60 years; AIDA GIMEMA for APL patients. All patients submitted to the AML10 and AML13 protocols and those patients submitted to the AIDA protocol with difficult peripheral vein access had a central venous catheter (CVC) sited. Patients treated as in-patients were discharged at the end of consolidation chemotherapy provided they were in a good clinical condition. They were routinely evaluated on an out-patient basis twice weekly. In the event of any complication they were referred to the Emergency Unit of our Department dedicated to out-patients with hematologic diseases.

RESULTS

One hundred and eleven patients with AML were eligible for intensive chemotherapy. After achievement of complete remission they received a total of 133 consolidation courses and in 127 instances they were followed on an out-patient basis during the aplastic phase. There were 69 cases (54%) of rehospitalization, 68 because of fever and only one because of severe anemia. Rehospitalization occurred in 90%,70% and 38% of courses in AML10, AML13 and AIDA protocols, respectively. Only one patient died: the cause of death was a brain hemorrhage. Coagulase negative staphylococci and viridans streptococci were the organisms most frequently isolated from blood. Most coagulase negative staphylococci were isolated in patients submitted to AML10 and AML13 protocols, who had an indwelling CVC. Empiric once-a-day antibacterial therapy with ceftriaxone and amikacin was effective in 75% of the cases and made early discharge possible in 28% of the cases with antibiotic therapy continued in an out-patient setting. Overall, patients were managed out of the hospital for 66% of the period of post-consolidation neutropenia (77%, 48% and 50% of the post-consolidation neutropenia period in patients treated with AIDA, AML10 and AML13 protocols, respectively).

INTERPRETATION AND CONCLUSIONS

Thanks to the availability of an emergency unit specifically dedicated to out-patients with hematologic diseases, selected out-hospital management of AML patients during post-consolidation cytopenia is a feasible, well accepted and cost-saving option, and can contribute to lower the risk of developing severe nosocomial infections. The empiric therapy with once-a-day ceftriaxone plus amikacin was effective, with the exception of staphylococcal infections, and made it possible to discharge patients early to continue treatment in an out-patient setting.

Three new butenolide lipids from the caribbean gorgonian pterogorgia anceps

Three novel fatty acid derivatives (1-3), containing one or two butenolide moieties, were isolated from the Caribbean gorgonian Pterogorgia anceps and chemically characterized by spectroscopic methods and comparison with known compounds. The new molecules were structurally related to ancepsenolide (4), a typical metabolite from Pterogorgia species, which was not detected in this collection of P. anceps.

HLA-C and HLA-DQB1 compatibility in unrelated cord blood transplants

BACKGROUND AND OBJECTIVE

Umbilical cord blood (UCB) cells have been definitively proved to be a source of hematopoietic stem cells with repopulating capacity when transplanted into pediatric hosts with neoplastic or non-neoplastic disease. Moreover, due to the immaturity of the UCB lymphoid compartment, these transplants are usually associated with a low incidence and severity of GvHD. This clinical observation and the immaturity of the UCB lymphoid compartment justify the acceptance of UCB units which differ from their recipient by 1 or 2 HLA antigens of the six HLA A, B and DRB1 antigens conventionally typed. Whether the number and type of HLA disparities affect clinical outcome of UCB transplants has not, however, been clearly demonstrated yet.

DESIGN AND METHODS

In the present study on 14 pediatric patients with high risk leukemia transplanted with UCB from unrelated donors, evaluation of HLA compatibility was extended to HLA-C and DQB1 genes and correlated to the engraftment rate and occurrence of GvHD. Conditioning regimen and GvHD prophylaxis were identical in all cases. HLA-A and B antigens were typed by serology, whereas DNA based methods were used to define HLA-C gene groups, and HLA-DRB1 and DQB1 alleles.

RESULTS

Conventional HLA-A, B and DRB1 typing demonstrated that 12 recipient/donor pairs differed at one HLA locus, while 2 pairs had 2 HLA disparities. The extended HLA-typing showed that only one out of the six pairs with a different HLA-A locus had additional mismatches at HLA-C and DQB1 loci, whereas all the remaining 8 pairs, which already differed at HLA-B and/or DRB1 loci after conventional typing, had additional HLA-C and/or DQB1 mismatches (p = 0.002). By contrast, engraftment rate and occurrence of GvHD did not significantly correlate with level of HLA-mismatches even after extended HLA-typing.

INTERPRETATION AND CONCLUSIONS

The present data show that additional mismatched HLA-C and/or DQB1 antigens are significantly more frequent in pairs which after conventional HLA-typing differed at HLA-B and/or DRB1 loci, than in those showing one HLA-A mismatch. This observation provides an additional criterion for selection of UCB donors with the closest HLA-match when more than one unit are available. We did not, however, observe any correlation between engraftment rate, occurrence of GvHD and degree of HLA disparities detected either by standard or extended typing. These data support the notion that certain HLA differences do not affect the clinical outcome of UCB transplants and indicate that the expensive and time consuming molecular typing of HLA-C and DQB1 loci might be avoided for UCB donor selection.

Volvatellin, caulerpenyne-related product from the sacoglossan volvatella sp

Volvatellin (4) is a highly unstable terpene isolated from the extracts of the Indian opisthobranch mollusk Volvatella sp. The structure and the relative stereochemistry of 4 were determined by NMR methods. The paper also describes a hypothetical biosynthesis of 4 starting from the alga-derived caulerpenyne.

Outpatient management of acute promyelocytic leukemia after consolidation chemotherapy

The feasibility and safety of outpatient management of acute promyelocytic leukemia (APL) during the aplastic phase after intensive consolidation chemotherapy, the incidence and types of complications requiring readmission to hospital, and the number of hospital days spared by this policy have been prospectively evaluated. After chemotherapy administration, patients were evaluated on an ambulatory basis. In the event of any complication they referred to the Emergency Unit (EU) of our Department dedicated to outpatients with hematologic diseases. Forty patients with APL observed over a 4 year period were eligible for intensive chemotherapy. After the achievement of complete remission they received a total of 104 consolidation courses and in 98 instances they were followed on an ambulatory basis. There were 41 cases (42%) of rehospitalization for fever (40 cases) or severe anemia (one case). Only one patient died due to a brain hemorrhage. Streptococcus viridans was the organism most frequently isolated from blood. Empiric once-a-day antibacterial therapy with ceftriaxone and amikacin was effective in 87% of the cases and made possible early discharge in 28% of the cases to continue the antibiotic therapy on an outpatient setting. Patients were managed out of the hospital for 76% of the post-consolidation neutropenia period. Thanks to the availability of an EU specifically dedicated to outpatients with hematologic diseases, out-hospital management of APL patients after consolidation therapy appeared to be safe, well accepted, potentially cost-saving, and contributed to saving the risk of developing severe nosocomial infections.

Elimination of cytokine production in stored platelet concentrate aliquots by photochemical treatment with psoralen plus ultraviolet A light

BACKGROUND

Cytokines generated in platelet concentrates (PCs) during storage have been implicated as possible mediators of febrile nonhemolytic transfusion reactions. Two potential methods of white cell inactivation were compared for their ability to reduce cytokine synthesis in pooled random-donor PC aliquots: treatment with gamma-radiation and photochemical treatment (PCT) using psoralens and ultraviolet A light.

STUDY DESIGN AND METHODS

ABO-matched PC aliquots were pooled and divided into separate aliquots. Aliquots (20 mL) were taken from each pool to serve as an untreated control and to undergo gamma-radiation. Aliquots were treated by using either gamma-radiation (2500 or 5000 cGy) or virucidal PCT. PCT with the psoralens 8-methoxypsoralen (8-MOP), aminomethyltrimethyl psoralen (AMT), and S-59 was investigated. PC aliquots were stored for 7 days and analyzed for levels of interleukin 8 by use of an enzyme-linked immunosorbent assay. Levels of DNA adduct formation were determined by using 3H-labeled psoralens.

RESULTS

Levels of interleukin 8 in the untreated random-donor PC aliquots increased with increasing white cell counts, but they were not affected by pooling. The untreated control aliquots and the aliquots treated with gamma-radiation had significant increases in levels of interleukin 8 after 5 to 7 days of storage (p<0.05). PCT with S-59 resulted in a significant reduction in cytokine synthesis (p<0.05). Day 5 to 7 levels of interleukin 8 did not differ significantly from Day 0 levels. Inhibition of interleukin 8 production by PCT increased with increasing levels of DNA modification (S-59 > AMT > 8-MOP).

CONCLUSION

PCT that utilizes S-59 has been developed to inactivate potential viral and bacterial pathogens in PC aliquots while maintaining in vitro platelet function. These data demonstrate that PCT of aliquots of pooled PC aliquots before storage also prevents white cell cytokine synthesis during storage. PCT may therefore offer the potential for reducing cytokine-associated febrile nonhemolytic transfusion reactions.

A prospective molecular study of chimaerism in patients with haematological malignancies receiving unrelated cord blood or bone marrow transplants: detection of mixed chimaerism predicts graft failure with or without early autologous reconstitution in cord blood recipients

We prospectively studied the chimaerism status in the bone marrow (BM) and peripheral blood (PB) of 23 patients receiving umbilical cord (UCB, 14 cases) or BM (nine cases) transplants from unrelated donors by PCR amplification of four individual-specific VNTR genetic loci. Haematological engraftment, with persistent full donor pattern. was observed in 10/14 (72%) patients receiving UCB and in 9/9 (100%) patients transplanted with marrow from an unrelated donor (MUD). In contrast, the remaining four patients converted to an autologous pattern. Three out of these four patients had an early autologous haematological reconstitution reaching a neutrophil level >0.5 x 10(9)/l at days 27, 33 and 37 after transplant, respectively. In all three of these patients, chimaerism analysis demonstrated an early appearance of donor cells (i.e. within 35 d after UCB transplant) showing a transient full donor (one case) or mixed chimaerism condition (two cases). Despite the early autologous haemopoietic reconstitution, one of the three patients died of GVHD at day 60, which was explained by the demonstration of low levels of donor lymphoid cells. In the MUD group all nine patients converted to a persistent full donor pattern with haematological reconstitution, accompanied in two of them by transient mixed chimaerism lasting to days 60 and 270 after transplant. Our data show that monitoring of chimaerism may predict graft failure with or without early autologous haemopoietic reconstitution in patients receiving unrelated UCB transplants. Furthermore, chimaerism analysis may identify, in patients with autologous reconstitution, those at risk of severe GVHD in whom immunosuppressive therapy should not be discontinued.

Umbilical cord blood transplant from unrelated HLA-mismatched donors in children with high risk leukemia

In the last 3 years, 14 children with high-risk leukemia (11 ALL, 2 AML and 1 CML) underwent cord blood transplantation from unrelated HLA-mismatched donors at a median of 99 days from the start of search. Eight patients were transplanted in second CR, one in accelerated phase, three at relapse and two patients in first CR. Conditioning regimen (fractionated TBI, etoposide, CY and anti-lymphocyte serum) and prophylaxis of GVHD (CsA and 6-methylprednisolone) were identical for all patients. Neutrophils >0.5x10(9)/l were reached at a median of 33 days from transplant, but in four cases we observed an autologous hematopoietic reconstitution (three spontaneous, one after autologous BM rescue). Acute and chronic GVHD were observed in 10/14 and 3/8 evaluable cases, respectively. Three patients died of transplant-related toxicity and three patients relapsed. The probabilities of event-free, disease-free and overall survival were 50, 53 and 64%, respectively. Cord blood transplant from HLA-mismatched unrelated donor is a valid option for the treatment of children with high-risk leukemia. With our eligibility criteria, conditioning regimen and prophylaxis of graft-versus-host disease, the main obstacles to successful transplant were represented by graft failure and fatal acute GVHD.

New minor diterpenoid diacylglycerols from the skin of the nudibranch anisodoris fontaini

The Patagonian dorid nudibranch Anisodoris fontaini contains in its mantle a series of isocopalane diterpenoid diacylglycerols. Five new minor metabolites, anisodorins 1-5 (1-5), along with the already reported 6 and 7, have been isolated and chemically characterized. The structure and the relative stereochemistries have been determined by spectroscopic means, while the absolute stereochemistries for 2-5 are suggested to be the same as for the biogenetically related major compounds 6 and 7. Synthesis of the enantiomer (8) of anisodorin 1 confirmed the proposed structure and absolute stereochemistry.

Interstitial insertion of AF10 into the ALL1 gene in a case of infant acute lymphoblastic leukemia

The ALL1 gene at 11q23 is a promiscuous gene participating in chromosomal abnormalities of acute leukemias with 1 of over 30 potential partner genes. Among these, the AF10 gene at band 10p12 has been recently cloned and characterized. Acute leukemias with the ALL1/AF10 chimeric gene frequently show heterogeneity in the breakpoints on 10p, as well as complex insertion (10;11) as a result of complex molecular mechanisms leading to the ALL1/AF10 fusion. In this context, we report the first description of an infant acute lymphoblastic leukemia with an interstitial insertion of the AF10 gene into the 11q23 band, resulting in the transcription of the ALL1/AF10 fusion product. Furthermore, we show how different diagnostic tools such as molecular, cytogenetic, and fluorescence in situ hybridization (FISH) analyses should be combined to resolve complex situations in the 11q23 setting.

First chemical study of patagonian nudibranchs: A new seco-11, 12-spongiane, tyrinnal, from the defensive organs of tyrinna nobilis

The Patagonian nudibranch Tyrinna nobilis contains a number of terpenoids, the novel seco-11,12-spongiane tyrinnal (1) and the known sesquiterpenoids dendrolasin (2), pallescensin A (3), and dehydropallescensin-2 (4). The metabolites probably derive from dietary sponges, thus suggesting a parallelism between the ecological relationships of T. nobilis and those of mollusks of genus Cadlina. The structure of 1 was determined by spectroscopic methods.

Umbilical cord blood (UCB) transplant from unrelated mismatched donor in patients with high risk (HR) leukemia

Ten consecutive children with high risk leukemia have been submitted to UCB transplant from unrelated HLA mismatched donors. All patients received an identical regimen for conditioning and GVHD prophylaxis. The median dose of viable nucleated cells infused was 2.6 x 10(6)/kg b.w. Among the nine patients evaluable for engraftment the hematopoiesis was of full donor origin in six patients and autologous in three. At a median follow-up of 9 months, six of nine (67%) patients are alive in CR.

Umbilical cord blood transplant from HLA-mismatched unrelated donor in high-risk leukemia

Twelve consecutive children with high-risk leukemia have been submitted to UCB transplant from unrelated 1 or 2 loci HLA-mismatched donor. All patients received an identical regimen for conditioning and GVHD prophylaxis. The median dose of viable nucleated cells infused was 2.8 x 10(7)/kg bw (range 1.4-7.9). Of 11 patients evaluable for engraftment, the hematopoiesis was of full donor origin in seven patients and autologous in four. The probability of disease-free survival at 1 and 2 years from UCB transplant is 60 and 42%, respectively.

ALL1 gene alterations in acute leukemia: biological and clinical aspects

BACKGROUND AND OBJECTIVE

The ALL1 gene, also referred to as MLL, HRX or Htrx1, is interrupted in the vast majority of translocations involving the chromosome band 11q23. Alterations in this gene are reported in approximately 5-10% of acute leukemias (AL) and characterize different leukemic subtypes such as infant (< 12 months of age) AL, topoisomerase II inhibitors-related (TR) AL and a small subset of de novo AML and ALL. Distinguishing features of ALL1 alterations include the striking heterogeneity of its recombinations, i.e., more than 30 chromosome partners have been described in ALL1 rearrangements, and the lack of association with a definite lineage. The objective of this article is to review the biological and structural properties of ALL1 gene and its various fusion proteins, and to discuss the clinical relevance of these lesions with special emphasis on their role in molecular diagnosis and monitoring of minimal residual disease.

EVIDENCE AND INFORMATION SOURCES

The material examined in the present review includes data published by the authors in this field, articles and abstracts published in journals covered by the Science Citation Index and Medline, as well as some more recent personal unpublished observations.

STATE OF THE ART

The ALL1 gene spans approximately 90 kb of DNA in length, and consists of 36 exons, ranging in size from 65 bp to 4249 bp. ALL1 codifies for a major transcript of approximately or equal to 15 kb. It encodes a protein of more than 3910 amino acids, containing three regions sharing sequence homology with the Drosophila trithorax gene. These homologies suggest that ALL1 is a transcription factor controlling development and/or differentiation of human cells. To date, twelve ALL1 partner genes have been characterized which are involved in the following translocations: t(4;11), t(9;11), t(6;11), t(11;19), t(1;11) t(10;11), t(11;16), t(11;17) and t(X;11). Since all these genes do not share relevant homologies among each other, their putative role in ALL1 activation still remains to be clarified. The analysis of ALL1 breakpoint cluster region (bcr) shows that several DNA motifs implicated in illegitimate recombination events are located within the bcr. Thus, mapping of breakpoints in the different subtypes of ALL1 +ve leukemia may help in understanding the events leading to translocations in human ALs. In this respect, data on ALL1 breakpoint localization suggest that similar pathogenetic mechanisms may underlie infant and TR AL and that these events might differ from those occurring in de novo AL. The availability of this molecular marker provides a new tool for diagnostic purposes and characterization of ALs and for monitoring of minimal residual disease. To date, the prognostic value of ALL1 rearrangements has been clearly demonstrated for infant ALs only, whereas the clinical relevance of ALL1 rearrangements in the other leukemic subtypes needs further evaluation by future prospective studies on a larger number of patients homogeneously treated. As concerning studies on minimal residual disease, data on PCR monitoring of the ALL1/AF4 fusion transcript, resulting from the t(4;11) translocation, show the clinical relevance of this molecular test in predicting outcome and, as a consequence, in designing individual post-remission therapies.

PERSPECTIVES

It is expected that future studies will provide more detailed information regarding either the normal ALL1 function and/or the leukemogenic effect of ALL1 alterations, together with a better definition of the prognostic relevance of the hybrid proteins formed by this gene at diagnosis and during remission of disease.

Further Petroformynes from Both Atlantic and Mediterranean Populations of the Sponge Petrosia ficiformis

Five novel polyacetylenes (5-9) were isolated from two different populations of the sponge Petrosia ficiformis collected in the Mediterranean Sea and the Atlantic Ocean. Their structures were established by extensive NMR analysis and by comparison with known petroformynes.

Gastric antral vascular ectasia (the watermelon stomach): a brief case report

Herein, the endoscopic and histological features of a case of gastric antral vascular ectasia (watermelon stomach) occurring in a 76-year-old woman are described. The condition, first recognized by Jabbari et al in 1984, is a rare but important cause of severe gastrointestinal blood loss and chronic iron deficiency anemia. Differential diagnosis from portal hypertensive gastropathy, treatment and outcome of the watermelon stomach are discussed.

Therapy-related acute leukemia associated with involvement of 11q23 after high grade non-Hodgkin lymphoma

Therapy-related acute myeloid leukemias with balanced translocations affecting the 11q23 chromosome region are one of the most serious complications of treatments with topoisomerase II inhibitor drugs as epipodophillotoxins and anthracyclines. 1,2-5 These cases are usually associated with short interval time from previous chemotherapies, absence of myeloid dysplastic phase, hyperleukocytosis and young age. We and others have recently identified and cloned the ALL1 gene at 11q23 band (also named MLL, HRX. Hrxt) which is consistently altered in t-AML following therapies with topo II targeting drugs. However, there are few reports of cases of t-AML, clinically and biologically similar to the subtype of leukemias secondary to exposure to topo II inhibitors drugs but without the involvement of the ALL1 gene. These observations suggest that genes other than ALL1 which are etiopathogenetically relevant for hematological neoplasias are located in this cytogenetic region.