Elena Mirabile

The gene for SP-40,40 human homolog of rat sulfated glycoprotein 2, rat clusterin, and rat testosterone-repressed prostate message 2, maps to chromosome 8

Sulfated glycoprotein 2 (SGP-2) is a rat glycoprotein that is particularly abundant in seminal fluid, where it is found associated with the acrosome and the tail of mature spermatozoa; for this reason it has been suggested that it has an important role in spermatogenesis. On the basis of nucleotide sequence homology, it has been proposed that the orthologous human gene is that coding for serum protein-40,40 (SP-40,40), a serum protein also called complement lysis inhibitor (CLI), SP-40,40 has been shown to act as a control mechanism of the complement cascade: in fact, it prevents the binding of a C5b-C7 complex to the membrane of the target cell and in this way inhibits complement-mediated cytolysis. SGP-2 and SP-40,40 seem then to be part of different biological systems. Furthermore it has been shown that another protein, testosterone-repressed prostate message 2 (TRPM-2), shares sequence homology with SGP-2 and SP-40,40. TRPM-2 is expressed at high levels and in a temporally precisely defined manner in dying cells, an observation that would suggest its involvement in the cascade of events leading to cell death. We have used a large panel of 24 mouse/human hybrid cell lines and a cDNA for SGP-2, which is also highly homologous to that for rat clusterin, to map the chromosomal location of the orthologous human gene. The mapping data and the Southern analysis presented in this paper, in addition to the data available from the literature, strongly suggest that in the human genome there is a single locus homologous to the probe used and that it codes for the protein which has been called, in different species, SP-40,40, SGP-2, clusterin, and TRPM-2. The chromosomal mapping of the locus for this multiname protein should facilitate its cloning and a better understanding of the apparently many biological functions of its product.

Developmental origins and impact of BCR-ABL1 fusion and IKZF1 deletions in monozygotic twins with Ph+ acute lymphoblastic leukemia

The timing and developmental sequence of events for BCR-ABL1(+) acute lymphoblastic leukemia (ALL), usually associated with IKAROS (IKZF1) deletions, are unknown. We assessed the status of BCR-ABL1 and IKZF1 genes in 2 pairs of monozygotic twins, one pair concordant, the other discordant for Philadelphia chromosome positive (Ph(+)) ALL. The twin pair concordant for ALL shared identical BCR-ABL1 genomic sequence indicative of monoclonal, in utero origin. One twin had IKZF1 deletion and died after transplantation. The other twin had hyperdiploidy, no IKZF1 deletion, and is still in remission 8 years after transplantation. In the twin pair discordant for ALL, neonatal blood spots from both twins harbored the same clonotypic BCR-ABL1 sequence. Low level BCR-ABL1(+) cells were present in the healthy co-twin but lacked the IKZF1 deletion present in the other twins leukemic cells. The twin with ALL relapsed and died after transplantation. The co-twin remains healthy and leukemia free. These data show that in childhood Ph(+) ALL, BCR-ABL1 gene fusion can be a prenatal and possibly initiating genetic event. In the absence of additional, secondary changes, the leukemic clone remains clinically silent. IKZF1 is a secondary and probable postnatal mutation in these cases, and as a recurrent but alternative copy number change is associated with poor prognosis.

Presence of hemoglobinopathies in Sicily: a historic perspective.

Sicily, at the center of the Mediterranean, has been the meeting place of Eastern and Western civilizations, and in the Sicilian population the presence of many different alterations in the globin gene clusters can surely be considered testimony of past colonizations. From 1975 to 1994, 100,000 Sicilian subjects were screened by us to monitor the presence of hemoglobin (Hb) structural variants. In this paper we present the data gathered, emphasizing the high incidence (2.5%) of carriers of at least one abnormal Hb, and the great heterogeneity of globin molecular defects on the island. Twenty-six different mutations were identified: the most common occur in the beta-globin gene (beta(S), beta(C), deltabeta(Lepore), beta(G-San José), beta(O-Arab), but also quite frequent is the mutated allele alpha(J-Oxford). The chromosome haplotypes associated with some of them were characterized. Two uncommon Hbs, Copenhagen and D Punjab, and some 18 rare variants complete the wide spectrum of structural alterations of globin genes in Sicily. We think they are de novo mutations prevalently. It is not possible to exclude that the presence of a few of them is related to migratory phenomena, particularly from North Africa and East Asia. Numerous thalassemic alleles complete the picture of globin gene mutations in Silicy.

Phenotype-genotype correlation in Sicilian patients with Hb H.

Abstract: We studied 15 Sicilian subjects with Hb H disease correlating clinical examinations with hematological and molecular data. Seven different α‐thal mutations were identified: four deletion types (‐‐MED, ‐‐CAL, ‐α3.7, ‐α4.2) and three nondeletion types (αNcolα, αHphα, αCSα). All the patients had a zero‐gene chromosome (‐‐MED or ‐‐CAL), while the third α gene was deleted (‐α3.7, ‐α4.2) or inactive (αNcolα, αHphα, αCSα). In patients with the nondeletion genotype the analysis of hematological values revealed lower levels of RBC and Hb A2 and significantly higher levels of Hb H. The clinical variability was remarkable, ranging from totally asymptomatic conditions, casually diagnosed, to severe thalassemia intermedia with marked hemolytic crises, liver and spleen enlargement and the necessity for frequent transfusions. The genotype did not justify the gravity of the phenotype in every case, and the differences in clinical manifestations, also notable, are not easily explainable in subjects who apparently have the same genotype.

Detection of PICALM-MLLT10 (CALM-AF10) and outcome in children with T-lineage acute lymphoblastic leukemia.

Detection of PICALM-MLLT10 ( CALM-AF10 ) and outcome in children with T-lineage acute lymphoblastic leukemia

Use of PEG-interferon alfa-2a plus ribavirin as treatment for chronic HCV hepatitis in a child cured of ALL

To the Editor: The natural history of and the treatment options for chronic hepatitis C (HCV) infection, in longterm leukemia survivors, have not been well characterized. Several reports showed the efficacy of combination therapy with peginterferon (PEG-IFN) alfa-2a and ribavirin in immunocompetent adults with chronic HCV infection [1]. There are no data regarding the use of combination therapy with PEG-IFN in children [2]. We report on the administration of PEG-IFN alfa-2a in combination with ribavirin in a child who had chronic HCV infection acquired during treatment for acute lymphoblastic leukemia (ALL). She was treated for ALL in our institution at the age of 3. She had a 10-years history of high serum alanine aminotransferase concentration. She was subsequently diagnosed with HCV genotype-1b positive chronic active hepatitis. After a year of IFN-alfa administration, at the age of 14, she presented with high levels of both serum alanine aminotransferase concentration and baseline viral load. A percutaneous liver biopsy showed a moderate intralobular inflammation/necrosis. Therefore, according to a recently described treatment tailored for adults [1], we administered 180 mg of PEGIFN alfa-2a subcutaneously once weekly, plus daily ribavirin 1,000 mg for a total of 48 weeks. We adopted this dosage based on the fact that she had almost adult size (height 165 cm; weight 48 kg). The Institutional review board of our center approved this treatment and an informed consent was signed by patient’s parents. We assessed the efficacy of this combination therapy by measuring alanine aminotransferase concentration and by performing both qualitative and quantitative HCV RNA RT-PCR using the Cobas Amplicor HCV Monitor assay (Roche Diagnostics-LA Roche, Ltd., Basel, Switzerland). We evaluated therapy response after 1, 4, 8, 12, 24, and 48 weeks, respectively. We noted a dramatic decrease of serum alanine aminotransferase concentration (from 350 to 35 U/L), correlated with a significant decrement in viral load (from>5,000,000 to 50 IU/L). Although we used an adult dosage, no side effects related to the combination therapy have occurred. Three consecutive qualitative HCV-RNA RT-PCR assays have been performed at 3 and 6 months and 1 year from therapy withdrawal, each demonstrating an undetectable level of viral RNA. Although the implementation of blood donor screening, the prevalence of anti-HCV seropositivity among leukemia survivors is still high [3]. Evidence of progression to liver failure in survivors of pediatric malignancies has been reported [3]. Because their previously immunocompromized status might have promoted more rapid viral replication, increasing the risk for a rapid disease progression, amore aggressive approach regarding the use of antiviral therapy in this population with chronic HCV is needed. Based on our experience, we suggest that administration of PEG-IFN in association with ribavirin should be considered as first line treatment in childrenwith chronic HCV hepatitis who have been previously cured of malignancies.

Association of Hb S/Hb lepore and δβ-thalassemia/Hb lepore in Sicilian patients: Review of the presence of Hb lepore in Sicily

Abstract: The hemoglobin (Hb) lepore‐Boston is a β‐globin structural variant, produced in a reduced amount and formed from the fusion of N‐terminus δ‐(residues 1–87) and C‐terminus β‐chains (residues 116–146). This type of fusion protein is quite common in Southern Italy (Campania, Calabria, and Sicily). We report here the hematological and hemoglobin data on 96 unrelated Sicilians with Hb lepore trait. Particularly interesting are the subjects where Hb lepore occurs with Hb S or Sicilian type δβ‐thalassemia. In these individuals, striking features are clinical variability and different hematological pictures. These observations underscore the importance of thalassemia screening in these geographic areas, such as Southern Italy, principally Sicily, where the mutations in globin gene clusters are especially prevalent. Moreover, as from the second half of the last century, owing to high migratory flux from Sicily to Northern Europe, North and South America, and Australia, the Hb lepore, as well as other hemoglobin variants, have become prevalent, making the identification of the heterozygotes a problem of general interest.

Acute differentiated dendritic cell leukemia: a variant form of pediatric acute myeloid leukemia with MLL translocation

Acute differentiated dendritic cell leukemia: a variant form of pediatric acute myeloid leukemia with MLL translocation

Genetic characterization of general transcription factors TFIIF and TFIIB of Homo sapiens sapiens

Analysis of loci GTF2F1 and GTF2B, encoding Rap 74 (a subunit of TFIIF) and TFIIB, respectively, showed that they are present in a single copy in the human genome and are localized at 19p13.3 and 1p22, respectively. By using as probe a cDNA for Rap 30 (the other subunit of TFIIF), we localized the GTF2F2 locus to 13q14; the same probe also detected a cross-hybridizing sequence at 4q31 whose functional importance remains to be elucidated. These data and those previously published by our group demonstrate that genes coding for class II general transcription factors with reported sequence similarity to bacterial sigma proteins are scattered in different regions of the human genome, with no evidence of clustering. This dispersion and the identification of homologs of both TBP and TFIIB in Archaea suggest an early evolutionary origin of the general transcription apparatus of contemporary eukaryotes.

Prognostic impact of t(9;11) in childhood acute myeloid leukemia (AML).

We read with considerable interest the recent report by Rubnitz et al, regarding the occurrence of t(9;11)(p22;q23) as the most favorable genetic factor for children with acute myeloid leukemia (AML) who were treated at their institution. Although we agree with the authors’ conclusions, we would emphasize the unfavorable prognostic value of t(9;11) occurrence in association with additional chromosomal alterations and/or with a FAB different from M5. In order to support this concept, we report here a case of a 2-year-old boy presenting with an AML FAB M1 and low white blood cell (WBC) count who was diagnosed and treated with a BFM protocol at the Center of Pediatric Hematology Oncology, University of Catania. The cytogenetic analyses, performed at the Gaslini Hospital, showed the presence of the t(9;11)(p22;q23) with additional chromosomal abnormalities [46,Y,der(X) (9qter49q34::Xp11.2-4Xqter) (der(9)(11qter-411q23::9p22-49q34:: 17q2?4-417qter), der(11) (11pter-411q23::9p2249pter), der(17) (17pter-417q2?4::Xp 11.2-4Xpter). The child achieved morphological remission after two courses of induction therapy. Since he withdrew the consolidation phase, he suffered from a chronic thrombocytopenia. The bone marrow (BM) aspirate showed a low number of blasts. We consistently detected the fusion transcript MLL-AF9 using a recently described RT-PCR protocol. The child then underwent a reinduction therapy (IDAFLAG), achieving a partial morphological remission. As a last resort, we subsequently performed an allogeneic BM transplantation (BMT) from a sibling HLA-matched donor using low doses of cyclosporin as graft-versus-host (GVH) disease prevention in an attempt to induce a graft-versus-leukemia phenomenon. Interestingly, the patient achieved remission after a cutaneous grade III GVH. However, at 60 days from BM infusion, he presented with second isolated (BM) relapse. As a result of the high expression of CD33 antigen in patient’s blasts, we decided to treat him with mylotarg followed by a second BMT. Unfortunately, after the second administration of anti-CD33 drug, the child died of infectious complication (aspergillosis). Here we report a single case that in addition to others previously reported in the literature, indicates that the occurrence of t(9;11) in childhood AML associated with additional chromosomal alterations and/or a FAB different from M5 could be considered an adverse prognostic factor. Even if in only a few pediatric cases, the trend of this supposition found in the authors’ findings showed that the t(9;11) positive patient 18 (FAB M7) and patient 21 (FAB M5) both presented with additional translocations have died and relapsed, respectively. In addition, the authors showed that 14 out of 17 cases with a FAB different from M5 associated with 11q23 abnormality and/ or MLL gene rearrangement have died. Although having a low WBC at diagnosis, which was demonstrated by the authors to be an independent good prognostic factor, 13 of these 17 cases died. To date, recent evidence has showed that acute leukemias with MLL gene rearrangement seem to represent a different disease from both acute lymphoblastic leukemia (ALL) and AML, presenting with a specific gene expression profile. Reporting our case, we suggest that the occurrence of t(9;11) at an immature stage of myeloid committed stem cell is associated with a resistant disease and a poorer prognosis. In contrast, the use of a specific chemotherapy drug (2-chlorodeoxyadenosine) is effective against FAB M5 AML, as recently reported. Thus, it is conceivable that the type of hematopoietic cells targeted by MLL rearrangements influences the drug sensitivity of transformed blasts. According to recent evidence on childhood ALL with 11q23 alterations, it is possible that leukemic cells with MLL rearrangement involve early progenitor cells that are more likely to exhibit drug resistance than are cells from patients older than 1 year or, in case of AML with FAB M5, harboring the same genetic change.