Nicola Orrù

High frequency of the TARDBP p.Ala382Thr mutation in Sardinian patients with amyotrophic lateral sclerosis

Orrù S, Manolakos E, Orrù N, Kokotas H, Mascia V, Carcassi C, Petersen MB. High frequency of the TARDBP p.Ala382Thr mutation in Sardinian patients with amyotrophic lateral sclerosis.

Gynecomastia in a male after dasatinib treatment for chronic myeloid leukemia

21: 1532–1544. 6 Murray F, Darzentas N, Hadzidimitriou A, Tobin G, Boudjogra M, Scielzo C et al. Stereotyped patterns of somatic hypermutation in subsets of patients with chronic lymphocytic leukemia: implications for the role of antigen selection in leukemogenesis. Blood 2008; 111: 1524–1533. 7 Hamblin TJ, Davis Z, Gardiner A, Oscier DG, Stevenson FK. Unmutated Ig V(H) genes are associated with a more aggressive form of chronic lymphocytic leukemia. Blood 1999; 94: 1848–1854. 8 Mayr C, Speicher MR, Kofler DM, Buhmann R, Strehl J, Busch R et al. Chromosomal translocations are associated with poor prognosis in chronic lymphocytic leukemia. Blood 2006; 107: 742–751.

Homozygosity for killer immunoglobin-like receptor haplotype A predicts complete molecular response to treatment with tyrosine kinase inhibitors in chronic myeloid leukemia patients.

Several recent reports suggest a possible role for killer immunoglobulin-like receptors (KIR) in the onset of chronic myeloid leukemia (CML) and response to therapy with tyrosine kinase inhibitors (TKIs). To explore this hypothesis, we studied KIRs and their human leukocyte antigen class I ligands in 59 consecutive patients with chronic-phase CML (mean age, 53 years; range, 23-81 years) and a group of 121 healthy control participants belonging to the same ethnic group as the patients. The 2-year cumulative incidence of complete molecular response, obtained after a median of 27 months (range, 4-52 months), was 51.2%. An increased frequency of the activating receptor KIR2DS1 (pm = 0.05) and a reduced frequency of the KIR-ligand combination KIR2DS2/2DL2 absent/C1 present (pm = 0.001) were significantly associated with CML. Moreover, KIR repertoires in patients appeared to influence response to TKI therapy. Homozygosity for KIR haplotype A (pm = 0.01), a decreased frequency of the inhibitory KIR gene KIR2DL2 (pm = 0.02), and low numbers of inhibitory KIR genes (pm = 0.05) were all significantly associated with achievement of complete molecular remission. These data suggest that a decrease in properly stimulated and activated NK cells might contribute to the occurrence of CML and indicate homozygosity for KIR haplotype A as a promising immunogenetic marker of complete molecular response that could help clinicians decide whether to withdraw treatment in patients with CML.

The role of killer immunoglobulin-like receptor haplotypes on the outcome of unrelated donor haematopoietic SCT for thalassaemia

Recent insight into the pathophysiology of acute GVHD after allogeneic haematopoietic SCT has led to a growing interest in the role of natural killer (NK) cells. NK cell cytotoxicity is mainly regulated by the interaction of activating and inhibitory killer immunoglobulin-like receptors (KIRs) with their respective ligands. To investigate the impact of KIRs and their ligands on haematopoietic SCT outcome, we performed a retrospective study of 78 transfusion-dependent thalassaemia patients (median age 10 years, range 1–29 years) transplanted from an unrelated donor selected using high-resolution molecular typing for both class I and II loci after a myeloablative conditioning regimen. GVHD prophylaxis consisted of CsA, short-term MTX and anti-thymocyte globulin in all patients. We found that patients transplanted from donors homozygous for KIR haplotype A had a greater risk of developing grade II–IV acute GVHD compared with those transplanted from a donor carrying at least one B haplotype (hazard ratio=4.5, 99% confidence interval=1.2–17.1, P=0.003). Our study suggests that KIR genotyping of donor and recipient pairs could contribute to the identification of patients at high risk for developing severe complications of haematopoietic SCT and thus may help with the choice of intensity of GVHD prophylaxis.

Recipient CTLA-4*CT60-AA genotype is a prognostic factor for acute graft-versus-host disease in hematopoietic stem cell transplantation for thalassemia

Polymorphisms of the cytotoxic T-lymphocyte antigen-4 gene (CTLA-4) have been associated with autoimmune diseases and it has recently been reported that donor genotypes correlate with the outcome of allogeneic hematopoietic stem cell transplantation in leukemia patients. With the aim of confirming this finding in thalassemia patients, we investigated the influence of genotype distribution of 3 CTLA-4 gene polymorphisms in 72 thalassemia patients and their unrelated donors. A significant association was observed for recipient CT60-AA genotype and onset of grade II–IV (63.2% vs 24.5%; p = 0.001) and grade III–IV (36.4% vs 7.6%; p = 0.005) acute graft-versus-host disease (aGVHD). The same association was observed for the 88-base-pair allele of the CTLA-4 (AT)n polymorphism, which was determined to be in complete linkage disequilibrium with the CT60 A allele. Multinomial Cox regression demonstrated that this association was independent of CT60 donor genotypes or other risk factors (p = 0.016; hazard ratio = 2.8). Our data confirm that the genetic variability in CTLA-4 is an important prognostic factor for aGVHD and suggest that some of the risk factors for this complication are generated by recipient cells that persist after the myeloablative conditioning regimen.

Interactions between killer immunoglobulin-like receptors and their human leucocyte antigen Class I ligands influence the outcome of unrelated haematopoietic stem cell transplantation for thalassaemia: a novel predictive algorithm.

In a study conducted on 114 patients undergoing unrelated donor haematopoietic stem cell transplantation (HSCT) for thalassaemia, we observed that the lack of activating killer immunoglobulin‐like receptors (KIRs) on donor natural killer (NK) cells significantly increased the risk of graft‐versus‐host disease (GvHD) [hazard risk (HR) 4·2, 95% confidence interval (CI) 1·7–10·1, P = 0·002] and transplantation‐related mortality (HR 4·7, 95% CI 1·6–14·2, P = 0·01). The risk of GvHD furthermore increased when recipients heterozygous for HLA‐C KIR ligand groups (C1/C2) were transplanted from donors completely lacking activating KIRs (HR 6·1, 95% CI 1·9–19·2, P = 0·002). We also found that the risk of rejection was highest when the recipient was homozygous for the C2 HLA‐KIR ligand group and the donor carried two or more activating KIRs (HR 6·8, 95% CI 1·9–24·4, P = 0·005). By interpolating the number of donor activating KIRs with recipient HLA‐C KIR ligands, we created an algorithm capable of stratifying patients according to the immunogenetic risk of complications following unrelated HSCT. In clinical practice, this predictive tool could serve as an important supplement to clinical judgement and decision‐making.

Absence of activating killer immunoglobulin-like receptor genes combined with hepatitis C viral genotype is predictive of hepatocellular carcinoma

Killer immunoglobulin-like receptors and their human leukocyte antigen class I ligands have a critical role in natural killer cell response to viral pathogens and tumors. To investigate whether killer immunoglobulin-like receptor genes could influence the chronic course of hepatitis C virus infection and/or progression to hepatocellular carcinoma we retrospectively analyzed a cohort of 228 patients transplanted for hepatitis C virus-induced cirrhotic end stage liver disease, combined or not with hepatocellular carcinoma. We found that patients completely lacking activating killer immunoglobulin-like receptor genes had a high risk of developing hepatocellular carcinoma. Hepatitis C viral genotype and viral load are other risk factors that can influence the course of chronic hepatitis C virus infection. In our study, the risk conferred by hepatitis C viral genotypes was enhanced in patients lacking activating killer immunoglobulin-like receptors. These results point to an important role for activating killer immunoglobulin-like receptors in the control of hepatitis C virus infection and progression to hepatocellular carcinoma. In clinical practice, assessment of killer immunoglobulin-like receptor and hepatitis C viral genotype combinations should allow for more accurate monitoring of patients with chronic hepatitis C virus infection.

Familial occurrence of chronic myeloid leukemia

Although recent years have witnessed a dramatic improvement in our understanding of the pathogenesis of chronic myeloid leukemia (CML), the mechanisms by which the Philadelphia (Ph) chromosome is first formed are unknown and the role of heritable aspects and predisposing environmental factors in the etiology of the disease remains unclear [1]. Observations about CML occurring in families are rare, but a recent population-based study investigating malignancies among first-degree relatives of patients affected by myeloproliferative neoplasms (MPN), assessed a two-fold increased risk of developing CML [2]. Here, we describe the occurrence of CML in a brother and sister and discuss the possible role of heritable aspects in the pathogenesis of the disease. In March 1999, a 45-year-old female was referred to a hematology center for leukocytosis, (white blood cells (WBC) 145.76 10/L, hemoglobin (Hb) 8.5 g/dL, platelets (PLT) 7506 10/L), severe splenomegaly and fever. After a bone marrow aspirate, she was diagnosed with CML in the chronic phase. The karyotype 46,XX,t(9;22)(q34;q11), i(17)(q10) was found in 100% of the metaphases. Molecular analysis showed the b3a2 (p210) BCRABL fusion transcript. Cytoreductive therapy started with hydroxiurea 2.5 g/day. In April, WBC decreased to 15.96 10/L, with Hb1⁄4 8.5 g/dL and PLT1⁄4 7806 10/L. Therapy with interferon a 9 MU/day combined with cycles of subcutaneous Cytarabine 40 mg/day and hydroxiurea 1 g/day was scheduled. After 3 months of treatment, blood tests showed leukocytosis and thrombocytosis (WBC1⁄4 25.76 10/L, Hb1⁄4 8.9 g/dL, PLT1⁄4 4186 10/L); cytogenetic evaluation of bone marrow revealed 85% of metaphases harbouring the t(9;22) translocation. Bone marrow transplantation (BMT) was then considered and HLA typing showed: HLAA*11,*30; B*18,*55; Cw*03,*05; DRB1*03; DQB1*02. Because an HLA-match was not found within the family, BMT was performed from an unrelated donor in September 1999. The patient died 1 month after transplantation without achieving engraftment. In January 2007, her 50-year-old brother was admitted to our center for severe thrombocytosis and leukocytosis (PLT1⁄4 1.5676 10/L, WBC1⁄4 12.66 10/L, Hb1⁄4 14.5 g/dL). Bone marrow aspirate showed 46,XY,t(9;22)(q34;q11) in 90% of the metaphases and molecular analysis revealed the b3a2 (p210) BCR-ABL fusion transcript; JAK2v617f mutation was negative. Treatment was started with Imatinib 400 mg/day. Complete hematologic response was achieved after 27 days of therapy: blood tests showed WBC1⁄4 5.66 10/L, Hb1⁄414.2 g/dl, PLT1⁄4 4076 10/L. Complete cytogenetic and molecular response was achieved after 5 months of treatment with Imatinib and the patient continued to be in remission after 20 months of therapy. Patient HLA typing showed: HLA-A*03,*32; B*07,*64; Cw*07; DRB1*07,*11; DQB1*02,*07. Analysis of HLA haplotype segregation within the family revealed that the two affected siblings had inherited two different haplotypes from their parents and were therefore totally HLA-mismatched.