Genomic variants in members of the Krüppel-like factor gene family are associated with disease severity and hydroxyurea treatment efficacy in β-hemoglobinopathies patients

Aim: β-Type hemoglobinopathies are characterized by vast phenotypic diversity as far as disease severity is concerned, while differences have also been observed in hydroxyurea (HU) treatment efficacy. These differences are partly attributed to the residual expression of fetal hemoglobin (HbF) in adulthood. The Krüppel-like family of transcription factors (KLFs) are a set of zinc finger DNA-binding proteins which play a major role in HbF regulation. Here, we explored the possible association of variants in KLF gene family members with response to HU treatment efficacy and disease severity in β-hemoglobinopathies patients. Materials & methods: Six tag single nucleotide polymorphisms, located in four KLF genes, namely KLF3, KLF4, KLF9 and KLF10, were analyzed in 110 β-thalassemia major patients (TDT), 18 nontransfusion dependent β-thalassemia patients (NTDT), 82 sickle cell disease/β-thalassemia compound heterozygous patients and 85 healthy individuals as controls. Results: Our findings show that a KLF4 genomic variant (rs2236599) is associated with HU treatment efficacy in sickle cell disease/β-thalassemia compound heterozygous patients and two KLF10 genomic variants (rs980112, rs3191333) are associated with persistent HbF levels in NTDT patients. Conclusion: Our findings provide evidence that genomic variants located in KLF10 gene may be considered as potential prognostic biomarkers of β-thalassemia clinical severity and an additional variant in KLF4 gene as a pharmacogenomic biomarker, predicting response to HU treatment.

Role of Genomic Biomarkers in Increasing Fetal Hemoglobin Levels Upon Hydroxyurea Therapy and in β-Thalassemia Intermedia: A Validation Cohort Study

Hemoglobinopathies exhibit a remarkable phenotypic diversity in terms of disease severity, while individual genetic background plays a key role in differential response to drug treatment. In the last decade, genomic variants in genes located within, as well as outside the human β-globin cluster have been shown to be significantly associated with Hb F increase, in relation to hydroxyurea (HU) therapy in patients with these diseases. Here, we aim to determine the effect of genomic variants located in genes, such as MAP3K5, ASS1, NOS2A, TOX, PDE7B, NOS1, FLT1 and ARG2, previously shown to modulate fetal hemoglobin (Hb F) levels in patients with β type hemoglobinopathies and reflecting disease severity and response to HU therapy in an independent cohort of Greek patients with these diseases. We recruited and genotyped 45 β-thalassemia patients (β-thal), either transfusion-dependent (TDT) or non transfusion-dependent (NTDT), 42 Hb S (HBB: c.20A>T)-β-thal compound heterozygotes, who were treated with HU, as well as 53 healthy individuals, all of Hellenic origin. Our study showed that genomic variants of the MAP3K5, NOS2A and ARG2 gene are associated with HU therapy efficacy in Hb S-β-thal compound heterozygotes. We have also shown that FLT1 and ARG2 genomic variants are associated with the mild phenotype of NTDT patients. Our findings provide evidence that MAP3K5, NOS2A, ARG2 and FLT1 genomic variants could be considered as genomic biomarkers to predict HU therapy efficacy in Hb S-β-thal compound heterozygotes and also to describe disease severity in patients with β type hemoglobinopathies.

The prognostic significance of chromosome 17 abnormalities in patients with myelodysplastic syndrome treated with 5-azacytidine: Results from the Hellenic 5-azacytidine registry

In patients with myelodysplastic syndrome (MDS), the prognostic significance of chromosome 17 abnormalities has not yet been fully elucidated, except for isochromosome 17q that has been characterized as an intermediate risk abnormality in the Revised International Prognostic Scoring System (IPSS‐R). To further characterize the prognostic significance of chromosome 17 abnormalities we analyzed the hematologic and prognostic characteristics of 548 adult patients with MDS treated with 5‐azacytidine through the Hellenic 5‐azacytidine registry and found 32 patients with a chromosome 17 abnormality (6 with i[17q], 15 with ‐17, 3 with add[17p] and the rest with other rarer abnormalities, mostly translocations). The presence of a chromosome 17 abnormality was correlated with poor prognostic features (high IPSS, IPSS‐R, and WPSS scores) and a low overall survival rate (15.7 vs 36.4 months for patients without chromosome 17 abnormalities, Kaplan–Meier, Log Rank P < 0.00001), but these results were confounded by the fact that most (92.3%) of the cases with a chromosome 17 abnormality (with the exception of i(17q) that was found in all cases as an isolated abnormality) were found in the context of a complex karyotype. Nevertheless, one should not ignore the contribution of chromosome 17 abnormalities to the prognostic significance of a complex karyotype since 33.8% of complex karyotypes encompassed a chromosome 17 abnormality.

Effect of induction therapy with lenalidomide, doxorubicin and dexamethasone on bone remodeling and angiogenesis in newly diagnosed multiple myeloma

There is limited data regarding the efficacy and safety of lenalidomide, adriamycin and dexamethasone (RAD) combination on newly diagnosed multiple myeloma (NDMM) patients. There is also scarce information about the effect of lenalidomide on bone metabolism and angiogenesis in NDMM. Thus, we conducted a Phase 2 study to evaluate the efficacy and safety of RAD regimen as induction in transplant-eligible NDMM patients and we studied the effects on bone metabolism and angiogenesis. A total of 45 patients were enrolled. Following four cycles of RAD, the overall response rate was 66.7% and after a median follow up of 29.1 months (range 21.0-34.9), the median survival outcomes have not been reached yet. RAD had a favorable toxicity profile and did not impair stem cell collection. RAD significantly reduced bone resorption markers CTX (p = 0.03) and TRACP-5b (p < 0.01). Interestingly, RAD also increased bone formation markers bone-specific alkaline phosphatase (p = 0.036), procollagen type 1 amino-terminal propeptide (p = 0.028) and osteocalcin (p = 0.026), which has not been described before with lenalidomide-containing regimens in the absence of bortezomib coadministration. Furthermore, the angiogenic cytokines VEGF (p = 0.01), angiogenin (p = 0.02) and bFGF (p < 0.01) were significantly reduced post-RAD induction. Our results suggest that RAD is an effective induction regimen before autologous stem cell transplantation with beneficial effects on bone metabolism and angiogenesis.

Chronic myelomonocytic leukemia treated with 5-azacytidine - results from the Hellenic 5-Azacytidine Registry: proposal of a new risk stratification system

Hypomethylating agents are widely used in chronic myelomonocytic leukemia (CMML). We analyzed the characteristics of 88 patients with CMML homogeneously treated with 5-azacytidine (Hellenic 5-Azacytidine Registry). The overall response rate was 48.9% and the median overall survival (OS) 29.7 months. Out of the seven most widely used prognostic scoring systems for CMML, the Dusseldorf score (DUSS) showed the best prognostic capability (HR, 2.27; p < .001). Forty-one (48.8%) patients progressed to acute myeloid leukemia (AML) after a median time of 15.2 months following treatment initiation. High serum ferritin levels at diagnosis were independently correlated with low OS (HR, 2.84; p = .022), as were circulating blasts (HR, 3.47; p = .014), while a platelet count <100 × 10⁹/L was marginally predictive of lower OS (HR, 1.45; p = .06). We selected these three factors to create a new risk stratification system for CMML with three risk groups. Finally, we highlighted for the first time the prognostic significance of serum ferritin levels in CMML.

Whole transcriptome analysis of human erythropoietic cells during ontogenesis suggests a role of VEGFA gene as modulator of fetal hemoglobin and pharmacogenomic biomarker of treatment response to hydroxyurea in β-type hemoglobinopathy patients

BACKGROUND

Human erythropoiesis is characterized by distinct gene expression profiles at various developmental stages. Previous studies suggest that fetal-to-adult hemoglobin switch is regulated by a complex mechanism, in which many key players still remain unknown. Here, we report our findings from whole transcriptome analysis of erythroid cells, isolated from erythroid tissues at various developmental stages in an effort to identify distinct molecular signatures of each erythroid tissue.

RESULTS

From our in-depth data analysis, pathway analysis, and text mining, we opted to focus on the VEGFA gene, given its gene expression characteristics. Selected VEGFA genomic variants, identified through linkage disequilibrium analysis, were explored further for their association with elevated fetal hemoglobin levels in β-type hemoglobinopathy patients. Our downstream analysis of non-transfusion-dependent β-thalassemia patients, β-thalassemia major patients, compound heterozygous sickle cell disease/β-thalassemia patients receiving hydroxyurea as fetal hemoglobin augmentation treatment, and non-thalassemic individuals indicated that VEGFA genomic variants were associated with disease severity in β-thalassemia patients and hydroxyurea treatment efficacy in SCD/β-thalassemia compound heterozygous patients.

CONCLUSIONS

Our findings suggest that VEGFA may act as a modifier gene of human globin gene expression and, at the same time, serve as a genomic biomarker in β-type hemoglobinopathy disease severity and hydroxyurea treatment efficacy.

New film-coated tablet formulation of deferasirox is well tolerated in patients with thalassemia or lower-risk MDS: Results of the randomized, phase II ECLIPSE study

Once‐daily deferasirox dispersible tablets (DT) have a well‐defined safety and efficacy profile and, compared with parenteral deferoxamine, provide greater patient adherence, satisfaction, and quality of life. However, barriers still exist to optimal adherence, including gastrointestinal tolerability and palatability, leading to development of a new film‐coated tablet (FCT) formulation that can be swallowed with a light meal, without the need to disperse into a suspension prior to consumption. The randomized, open‐label, phase II ECLIPSE study evaluated the safety of deferasirox DT and FCT formulations over 24 weeks in chelation‐naïve or pre‐treated patients aged ≥10 years, with transfusion‐dependent thalassemia or IPSS‐R very‐low‐, low‐, or intermediate‐risk myelodysplastic syndromes. One hundred seventy‐three patients were randomized 1:1 to DT (n = 86) or FCT (n = 87). Adverse events (overall), consistent with the known deferasirox safety profile, were reported in similar proportions of patients for each formulation (DT 89.5%; FCT 89.7%), with a lower frequency of severe events observed in patients receiving FCT (19.5% vs. 25.6% DT). Laboratory parameters (serum creatinine, creatinine clearance, alanine aminotransferase, aspartate aminotransferase and urine protein/creatinine ratio) generally remained stable throughout the study. Patient‐reported outcomes showed greater adherence and satisfaction, better palatability and fewer concerns with FCT than DT. Treatment compliance by pill count was higher with FCT (92.9%) than with DT (85.3%). This analysis suggests deferasirox FCT offers an improved formulation with enhanced patient satisfaction, which may improve adherence, thereby reducing frequency and severity of iron overload‐related complications.

Treatment of chronic hepatitis C with direct-acting antivirals in patients with β-thalassaemia major and advanced liver disease

Interferon-based regimens for chronic hepatitis C (CHC) were often deferred in patients with β-thalasaemia major (β-TM) due to poor efficacy and tolerance. Current guidelines recommend direct-acting antivirals (DAAs) for these patients. The aim of this study was to assess the safety and efficacy of DAAs in patients with β-TM and advanced liver disease due to CHC. Patients were recruited from eight liver units in Greece. The stage of liver disease was assessed using transient elastography and/or liver histology. Five regimens were used: sofosbuvir (SOF) + ribavirin (RBV); SOF + simeprevir ± RBV; SOF + daclatasvir ± RBV; ledipasvir/SOF ± RBV and ombitasvir/paritaprevir-ritonavir + dasabuvir ± RBV. Sixty-one patients (median age 43 years) were included. The majority of patients was previously treated for hepatitis C (75%) and had cirrhosis (79%). Viral genotype distribution was: G1a: n = 10 (16%); G1b: n = 22 (36%); G2: n = 2 (3%); G3: n = 14 (23%); G4: n = 13 (22%). The predominant chelation therapy was a combination of deferoxamine and deferiprone (35%). Overall sustained virological response rates were 90%. All treatment regimens were well tolerated and no major adverse events or drug-drug interactions were observed. Approximately half of the patients who received RBV (7/16, 44%) had increased needs for blood transfusion. Treatment of CHC with DAAs in patients with β-TM and advanced liver disease was highly effective and safe.

Correlation of SIN3A genomic variants with β-hemoglobinopathies disease severity and hydroxyurea treatment efficacy

AIMS

Hemoglobinopathies, particularly β-thalassemia and sickle cell disease, are characterized by great phenotypic variability in terms of disease severity, while notable differences have been observed in hydroxyurea treatment efficacy. In both cases, the observed phenotypic diversity is mostly dependent on the elevated fetal hemoglobin levels, resulting from the persistent fetal globin gene expression in the adult erythroid stage orchestrated by intricate mechanisms that still remain only partly understood. We have previously shown that several protein factors act as modifiers of fetal hemoglobin production, exerting their effect via different pathways.

MATERIALS & METHODS

Here, we explored whether SIN3A could act as a modifier of fetal globin gene expression, as it interacts with KLF10, a known modifier of fetal hemoglobin production.

RESULTS

We show that SIN3A genomic variants are associated both with β-thalassemia disease severity (rs11072544) as well as hydroxyurea treatment response (rs7166737) in β-hemoglobinopathies patients.

CONCLUSION

Our findings further underline that fetal hemoglobin production is the result of a complex interplay in which several human globin gene cluster variants interact with protein factors encoded by modifier genes to produce the observed clinical outcome.

Genomic variants in the ASS1 gene, involved in the nitric oxide biosynthesis and signaling pathway, predict hydroxyurea treatment efficacy in compound sickle cell disease/β-thalassemia patients

AIM

Hemoglobinopathies exhibit a remarkable phenotypic diversity that restricts any safe association between molecular pathology and clinical outcomes.

PATIENTS & METHODS

Herein, we explored the role of genes involved in the nitric oxide biosynthesis and signaling pathway, implicated in the increase of fetal hemoglobin levels and response to hydroxyurea treatment, in 119 Hellenic patients with β-type hemoglobinopathies.

RESULTS

We show that two ASS1 genomic variants (namely, rs10901080 and rs10793902) can serve as pharmacogenomic biomarkers to predict hydroxyurea treatment efficacy in sickle cell disease/β-thalassemia compound heterozygous patients.

CONCLUSION

These markers may exert their effect by inducing nitric oxide biosynthesis, either via altering splicing and/or miRNA binding, as predicted by in silico analysis, and ultimately, increase γ-globin levels, via guanylyl cyclase targeting.

Efficacy of Interferon A-2b monotherapy in Β-thalassemics with chronic hepatitis C

BACKGROUND & AIMS

Monotherapy with standard or pegylated interferon (PegIFN) remains the first-line treatment for HCV infection in patients with thalassemia major (βTM), although its long-term impact is still unknown. We aimed to assess the efficacy of IFN-a2b/PegIFN-a2b (one or multiple treatment sessions) and the predictors for sustained virological response (SVR) in HCV-infected βTM patients.

METHODS

Between 11/1992 and 12/2013 [median follow-up: 165.5 months (8-237)], 48 βTM HCV-infected patients [19 males, median age: 22 years (12-45)], received IFN-a2b (n=34) or PegIFN-a2b (n=14). Twenty-three patients (47.9%) had a previous splenectomy; 13/40 (32.5%) patients had Ishak stage >/=4 and 21/40 (52.5%) had siderosis grade 3-4. HCV-genotype was available in 36 patients (genotype 1: 47.2%, 2: 5.6%, 3: 25%, and 4: 22%). IL28B genotype was determined in 37 patients by means of in-house real-time PCR (CC: 27%, CT: 62.2%, TT: 10.8%).

RESULTS

Totally, 15/48 (31.3%) achieved SVR following the first treatment and 18/48 (37.5%) after multiple courses. Splenectomy (p=0.01) and fibrosis grade >/=4 (p<0.05) were negative predictors for SVR (first course), whereas splenectomy (p<0.05) and age >18 (p<0.02) for SVR after multiple courses. In HCV-genotype 1/4 (n=25), none of the patients with CT or TT IL28B genotype achieved SVR compared to 50% of the CC patients (p=0.004).

CONCLUSIONS

Interferon is an effective therapeutic option in HCV-infected βTM patients. IL28B genotype was a strong predictor for SVR, together with splenectomy, age and fibrosis.

Genomic variation in the MAP3K5 gene is associated with β-thalassemia disease severity and hydroxyurea treatment efficacy

AIM

In this study we explored the association between genetic variations in MAP3K5 and PDE7B genes, residing on chromosome 6q23, and disease severity in β-hemoglobinopathy patients, as well as the association between these variants with response to hydroxyurea (HU) treatment. Furthermore, we examined MAP3K5 expression in the context of high fetal hemoglobin (HbF) and upon HU treatment in erythroid progenitor cells from healthy and KLF1 haploinsufficient individuals.

MATERIALS & METHODS

For this purpose, we genotyped β-thalassemia intermedia and major patients and healthy controls, as well as a cohort of compound heterozygous sickle cell disease/β-thalassemia patients receiving HU as HbF augmentation treatment. Furthermore, we examined MAP3K5 expression in the context of high HbF and upon HU treatment in erythroid progenitor cells from healthy and KLF1 haploinsufficient individuals.

RESULTS

A short tandem repeat in the MAP3K5 promoter and two intronic MAP3K5 gene variants, as well as a PDE7B variant, are associated with low HbF levels and a severe disease phenotype. Moreover, MAP3K5 mRNA expression levels are altered in the context of high HbF and are affected by the presence of HU. Lastly, the abovementioned MAP3K5 variants are associated with HU treatment efficacy.

CONCLUSION

Our data suggest that these MAP3K5 variants are indicative of β-thalassemia disease severity and response to HU treatment.

KLF10 gene expression is associated with high fetal hemoglobin levels and with response to hydroxyurea treatment in β-hemoglobinopathy patients

AIM

In humans, fetal hemoglobin (HbF) production is controlled by many intricate mechanisms that, to date, remain only partly understood.

PATIENTS & METHODS

Pharmacogenomic analysis of the effects of hydroxyurea (HU) on HbF production was undertaken in a collection of Hellenic β-thalassemia and sickle cell disease (SCD) compound heterozygotes and a collection of healthy and KLF1-haploinsufficient Maltese adults, to identify genomic signatures that follow high HbF patterns.

RESULTS

KLF10 emerged as a top candidate. Moreover, genotype analysis of β-thalassemia major and intermedia patients and an independent cohort of β-thalassemia/SCD compound heterozygous patients that do or do not respond to HU treatment showed that the homozygous mutant state of a tagSNP in the KLF10 3'UTR is not present in β-thalassemia intermedia patients and is underrepresented in β-thalassemia/SCD compound heterozygous patients that respond well to HU treatment.

CONCLUSION

These data suggest that KLF10 may constitute a pharmacogenomic marker to discriminate between response and nonresponse to HU treatment.

Hepatitis C in patients with β-thalassemia major. A single-centre experience

Chronic hepatitis C (CHC) and iron overload are the main causes of liver disease in β-thalassemia major (βTM). There is limited data regarding the course of CHC in this population. All patients (n=144) from the thalassemia centre of the University Hospital of Patras were evaluated (January 1981 to June 2012). Patients were classified into group A (n=57), which consisted of patients with CHC, who either had received antiviral treatment (n=49) or not (n=8), and group B which included 87 patients without CHC. Nineteen patients died during follow-up (median: 257.5 months (1-355)). Survival rates were 84.2 % and 88.5 % for group A and B, respectively. The causes of death were heart failure (63.2 %), accident (10.5 %), sepsis (5.3 %), liver failure (5.3 %), hepatocellular carcinoma (HCC) (5.3 %), non-Hodgkin lymphoma (5.3 %) and multiorgan failure (5.3 %). There were no differences in total survival between the two groups (p=0.524). In the multivariate analysis, survival was neither correlated with CHC (p=ns), nor with anti-HCV treatment (p=ns), whereas independent negative predictors were presence of heart failure (p<0.001), presence of malignancy other than HCC (p=0.001) and non-adherence to chelation treatment (p=0.013). Predictive factors for the development of cirrhosis were: CHC (p<0.001), age>35 years (p=0.007), siderosis grade 3/4 (p=0.029) and splenectomy (p=0.001); however, multivariately, only siderosis grade 3/4 was found to be significant (p=0.049). In this study, survival of patients with βTM was mainly associated with heart failure, presence of malignancy other than HCC and non-adherence to chelation treatment, rather than with liver disease. Multicentre studies need to be designed to define more accurately the indications of antiviral treatment in this population.

Extent of silent cerebral infarcts in adult sickle-cell disease patients on magnetic resonance imaging: is there a correlation with the clinical severity of disease?

The aim of this paper is to correlate the extent of silent cerebral infarcts (SCIs) on magnetic resonance imaging (MRI) with the clinical severity of sickle cell disease (SCD) in adult patients. Twenty-four consecutive adult asymptomatic SCD patients (11 male and 13 female) with a mean age of 38.4 years (range 20-59) were submitted to brain MRI on a 1 Tesla Gyroscan Intera, Philips MR scanner with a dedicated head coil. The protocol consisted of TSE T2-weighted and FLAIR images on the axial and coronal planes. MRI readings were undertaken by two radiologists and consensus readings. Patients were compound heterozygotes (HbS/β-thal). The extent of SCIs was classified from 0-2 with 0 designating no lesions. Clinical severity was graded as 0-2 by the hematologist, according to the frequency and severity of vaso-occlusive crises. There was no statistically significant correlation between the severity of clinical disease and the extent of SCIs on MR imaging. The extent of SCI lesions did not differ statistically between younger and older patients. Patients receiving hydroxyurea had no statistically significant difference in the extent of SCI lesions. The extent of SCIs in heterozygous (HbS/β-thal) SCD patients is not age related and may be quite severe even in younger (<38.4 years) patients. However the extent of SCIs is not correlated with the severity of clinical disease.

Plasma levels of lipoprotein-associated phospholipase A(2) are increased in patients with β-thalassemia

Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) is an independent cardiovascular risk factor. We investigated the plasma levels of Lp-PLA(2) activity and mass as a function of plasma lipid levels, LDL subclass profile, and oxidative stress in patients with β-thalassemia. Thirty-five patients with β-thalassemia major (β-TM) and 25 patients with β-thalassemia intermedia (β-TI) participated in the study. Lp-PLA(2) activity and mass were measured in total plasma, in apolipoprotein (apo)B-depleted plasma (HDL-Lp-PLA(2)), and in LDL subclasses. Lp-PLA(2) activity produced and secreted from peripheral blood monocytes in culture was also determined. Patients with β-thalassemia are characterized by a predominance of small-dense LDL particles, increased oxidative stress, and very high plasma levels of Lp-PLA(2) mass and activity, despite low LDL-cholesterol levels. A significant positive correlation between plasma Lp-PLA(2) activity or mass and 8-isoprostane (8-epiPGF2a) and ferritin levels as well as intima-media thickness (IMT) values was observed. An increase in secreted and cell-associated Lp-PLA(2) activity from monocytes in culture was observed in both patient groups. The HDL-Lp-PLA(2) activity and mass as well as the ratio of HDL-Lp-PLA(2)/plasma Lp-PLA(2) were significantly higher in both patient groups compared with the control group. In conclusion, patients with β-thalassemia exhibit high plasma Lp-PLA(2) levels, attributed to increased enzyme secretion from monocytes/macrophages and to the predominance of sdLDL particles in plasma. Plasma Lp-PLA(2) is correlated with carotid IMT, suggesting that this enzyme may be implicated in premature carotid atherosclerosis observed in β-thalassemia.