Expression Pattern and Prognostic Significance of the Long Non-Coding RNA Metastasis-Associated Lung Adenocarcinoma Transcript 1 in Chronic Lymphocytic Leukemia.

Dysregulated expression of the long non-coding RNA MALAT1 has been implicated in the pathogenesis and progression of a variety of cancers, including hematological malignancies, but it has been poorly investigated in chronic lymphocytic leukemia (CLL). In this study, the expression of MALAT1 was measured using a quantitative reverse-transcriptase polymerase chain reaction in the peripheral blood mononuclear cells of 114 unselected, newly diagnosed CLL patients in order to analyze its association with clinical, laboratory, and molecular patients' characteristics at diagnosis, as well as its prognostic relevance. MALAT1 was found to be upregulated in CLL patients in comparison to healthy controls, and expression levels were not related to age, leukocyte, lymphocyte and platelet count, serum ß2-microglobulin, and IGHV somatic hypermutational status. On the other hand, high MALAT1 expression was associated with several favorable prognostic markers (high hemoglobin, low serum lactate dehydrogenase, earlier clinical stages, CD38-negative status), but also with unfavorable cytogenetics. Furthermore, an association between high MALAT1 levels and longer time to first treatment and overall survival in IGHV-unmutated CLL subtype was observed. In summary, our results imply that high MALAT1 expression at diagnosis may be a predictor of better prognosis and point to MALAT1 expression profiling as a candidate biomarker potentially useful in clinical practice.

Germline Variants in Cancer Predisposition Genes in Pediatric Patients with Central Nervous System Tumors.

Central nervous system (CNS) tumors comprise around 20% of childhood malignancies. Germline variants in cancer predisposition genes (CPGs) are found in approximately 10% of pediatric patients with CNS tumors. This study aimed to characterize variants in CPGs in pediatric patients with CNS tumors and correlate these findings with clinically relevant data. Genomic DNA was isolated from the peripheral blood of 51 pediatric patients and further analyzed by the next-generation sequencing approach. Bioinformatic analysis was done using an "in-house" gene list panel, which included 144 genes related to pediatric brain tumors, and the gene list panel Neoplasm (HP:0002664). Our study found that 27% of pediatric patients with CNS tumors have a germline variant in some of the known CPGs, like ALK, APC, CHEK2, ELP1, MLH1, MSH2, NF1, NF2 and TP53. This study represents the first comprehensive evaluation of germline variants in pediatric patients with CNS tumors in the Western Balkans region. Our results indicate the necessity of genomic research to reveal the genetic basis of pediatric CNS tumors, as well as to define targets for the application and development of innovative therapeutics that form the basis of the upcoming era of personalized medicine.

Frequencies of EGFR single nucleotide polymorphisms in non-small cell lung cancer patients and healthy individuals in the Republic of Serbia: a preliminary study.

The purpose of this study was to determine the frequencies of EGFR -216G>T, -191C>A, and 181946C>T in Serbian non-small cell lung cancer (NSCLC) patients, as well as to compare it with healthy individuals, in order to assess their potential importance for lung cancer in Serbia. The study involved 56 NSCLC patients and 53 unrelated healthy volunteers, and genotyping was performed on DNA samples obtained from formalin-fixed paraffin-embedded lung tumor tissue and blood, respectively. This was the first time to show genotype frequencies of those single nucleotide polymorphisms for this study group from the territory of the Republic of Serbia. There was very strong evidence of association between age and death due to lung cancer (Pearson chi-square = 43.439, df = 2, p < 0,001), as well as between ever smoking and death due to lung cancer (Pearson chi-square = 31.727, df = 1, p < 0.001). When dominant genetic model (GG vs. GT+TT) was used for -216G>T, we have found significant association (p = 0.012) between -216GG genotype and NSCLC patients within smokers' subgroup. So, carriers of -216GG genotype had higher risk (OR = 4.33, 95 % CI = 1.324-14.179) than noncarriers (GT and TT) for developing non-small cell lung cancer in our patients.

Parallel targeted next generation sequencing of childhood and adult acute myeloid leukemia patients reveals uniform genomic profile of the disease.

The age-specific differences in the genetic mechanisms of myeloid leukemogenesis have been observed and studied previously. However, NGS technology has provided a possibility to obtain a large amount of mutation data. We analyzed DNA samples from 20 childhood (cAML) and 20 adult AML (aAML) patients, using NGS targeted sequencing. The average coverage of high-quality sequences was 2981 × per amplicon. A total of 412 (207 cAML, 205 aAML) variants in the coding regions were detected; out of which, only 122 (62 cAML and 60 aAML) were potentially protein-changing. Our results confirmed that AML contains small number of genetic alterations (median 3 mutations/patient in both groups). The prevalence of the most frequent single gene AML associated mutations differed in cAML and aAML patient cohorts: IDH1 (0 % cAML, 5 % aAML), IDH2 (0 % cAML, 10 % aAML), NPM1 (10 % cAML, 35 % aAML). Additionally, potentially protein-changing variants were found in tyrosine kinase genes or genes encoding tyrosine kinase associated proteins (JAK3, ABL1, GNAQ, and EGFR) in cAML, while among aAML, the prevalence is directed towards variants in the methylation and histone modifying genes (IDH1, IDH2, and SMARCB1). Besides uniform genomic profile of AML, specific genetic characteristic was exclusively detected in cAML and aAML.

Gene Mutation Profiles in Primary Diffuse Large B Cell Lymphoma of Central Nervous System: Next Generation Sequencing Analyses.

The existence of a potential primary central nervous system lymphoma-specific genomic signature that differs from the systemic form of diffuse large B cell lymphoma (DLBCL) has been suggested, but is still controversial. We investigated 19 patients with primary DLBCL of central nervous system (DLBCL CNS) using the TruSeq Amplicon Cancer Panel (TSACP) for 48 cancer-related genes. Next generation sequencing (NGS) analyses have revealed that over 80% of potentially protein-changing mutations were located in eight genes (CTNNB1, PIK3CA, PTEN, ATM, KRAS, PTPN11, TP53 and JAK3), pointing to the potential role of these genes in lymphomagenesis. TP53 was the only gene harboring mutations in all 19 patients. In addition, the presence of mutated TP53 and ATM genes correlated with a higher total number of mutations in other analyzed genes. Furthermore, the presence of mutated ATM correlated with poorer event-free survival (EFS) (p = 0.036). The presence of the mutated SMO gene correlated with earlier disease relapse (p = 0.023), inferior event-free survival (p = 0.011) and overall survival (OS) (p = 0.017), while mutations in the PTEN gene were associated with inferior OS (p = 0.048). Our findings suggest that the TP53 and ATM genes could be involved in the molecular pathophysiology of primary DLBCL CNS, whereas mutations in the PTEN and SMO genes could affect survival regardless of the initial treatment approach.

Somatic mutations of isocitrate dehydrogenases 1 and 2 are prognostic and follow-up markers in patients with acute myeloid leukaemia with normal karyotype.

BACKGROUND: Mutations in the isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2) genes are frequent molecular lesions in acute myeloid leukaemia with normal karyotype (AML-NK). The effects of IDH mutations on clinical features and treatment outcome in AML-NK have been widely investigated, but only a few studies monitored these mutations during follow-up. PATIENTS AND METHODS: In our study samples from 110 adult de novo AML-NK were studied for the presence of IDH1 and IDH2 mutations, their associations with other prognostic markers and disease outcome. We also analyzed the stability of these mutations during the course of the disease in complete remission (CR) and relapse. RESULTS: IDH mutations were found in 25 (23%) patients. IDH+ patients tend to have lower CR rate compared to IDH-patients (44% vs 62.2%, p = 0.152), and had slightly lower disease free survival (12 months vs 17 months; p = 0.091). On the other hand, the presence of IDH mutations had significant impact on overall survival (2 vs 7 months; p = 0.039). The stability of IDH mutations were studied sequentially in 19 IDH+ patients. All of them lost the mutation in CR, and the same IDH mutations were detected in relapsed samples. CONCLUSIONS: Our study shows that the presence of IDH mutations confer an adverse effect in AML-NK patients, which in combination with other molecular markers can lead to an improved risk stratification and better treatment. Also, IDH mutations are very stable during the course of the disease and can be potentially used as markers for minimal residual disease detection.

Optimization of PCR conditions for amplification of GC-Rich EGFR promoter sequence.

BACKGROUND: Polymerase chain reaction (PCR) is an extremely sensitive method that often demands optimization, especially when difficult templates need to be amplified. The aim of the present study was to optimize the PCR conditions for amplification of the epidermal growth factor receptor (EGFR) promoter sequence featuring an extremely high guanine-cytosine (GC) content in order to detect single nucleotide polymorphisms -216G>T and -191C>A. METHODS: Genomic DNA used for amplification was extracted from formalin-fixed paraffin-embedded lung tumor tissue and PCR products were detected by agarose gel electrophoresis. RESULTS: Results showed that addition of 5% dimethyl sulfoxide (DMSO), as well as DNA concentration in PCR reaction of at least 2 µg/ml, were necessary for successful amplification. Due to high GC content, optimal annealing temperature was 7°C higher than calculated, while adequate MgCl2 concentration ranged from 1.5 to 2.0 mM. CONCLUSION: In conclusion, EGFR promoter region is a difficult PCR target, but it could be amplified after optimization of MgCl2 concentration and annealing temperature in the presence of DMSO and the DNA template of acceptable concentration.

Pediatric acute myeloid leukemia: Insight into genetic landscape and novel targeted approaches.

Acute myeloid leukemia (AML) is a very heterogeneous hematological malignancy that accounts for approximately 20% of all pediatric leukemia cases. The outcome of pediatric AML has improved over the last decades, with overall survival rates reaching up to 70%. Still, AML is among the leading types of pediatric cancers by its high mortality rate. Modulation of standard therapy, like chemotherapy intensification, hematopoietic stem cell transplantation and optimized supportive care, could only get this far, but for the significant improvement of the outcome in pediatric AML, development of novel targeted therapy approaches is necessary. In recent years the advances in genomic techniques have greatly expanded our knowledge of the AML biology, revealing molecular landscape and complexity of the disease, which in turn have led to the identification of novel therapeutic targets. This review provides a brief overview of the genetic landscape of pediatric AML, and how it's used for precise molecular characterization and risk stratification of the patients, and also for the development of effective targeted therapy. Furthermore, this review presents recent advances in molecular targeted therapy and immunotherapy with an emphasis on the therapeutic approaches with significant clinical benefits for pediatric AML.

The influence of BCL2, BAX, and ABCB1 gene expression on prognosis of adult de novo acute myeloid leukemia with normal karyotype patients.

BACKGROUND: Deregulation of the apoptotic process underlies the pathogenesis of many cancers, including leukemia, but is also very important for the success of chemotherapy treatment. Therefore, the gene expression profile of main apoptotic factors, such as anti-apoptotic BCL2 (B-cell lymphoma protein 2) and pro-apoptotic BAX (BCL2-associated X), as well as genes involved in the multi-drug resistance (ABCB1), could have significant impact on the prognosis and could be used as targets for specific therapy. PATIENTS AND METHODS: We analyzed the expression of BCL2, BAX, and ABCB1 in bone-marrow samples collected at diagnosis from 51 adult patients with acute myeloid leukemia with normal karyotype (AML-NK) using real-time polymerase chain reaction method, and examined their prognostic potential. RESULTS: Increased expression of BCL2 (BCL2 +) was associated with the presence of chemoresistance (p = 0.024), while patients with low BAX expression were more prone to relapse (p = 0.047). Analysis of the combined effect of BCL2 and BAX expression showed that 87% of patients with BAX/BCL2 low status were resistant to therapy (p = 0.044). High expression of ABCB1 was associated with BCL2 + status (p < 0.001), and with absence FLT3-ITD mutations (p = 0.019). CONCLUSIONS: The present analysis of BCL2, BAX, and ABCB1 gene expression profiles is the first study focusing solely on AML-NK patients. Preliminary results showed that patients with high BCL2 expression are likely to experience resistance to chemotherapy, and may benefit from specific anti-BCL2 treatment. Further investigations conducted on a larger number of patients could elucidate actual prognostic significance of these genes in AML-NK patients.

Expression of BCL11A in chronic lymphocytic leukaemia.

INTRODUCTION: The B-cell lymphoma/leukaemia 11A (BCL11A) gene encodes a Krüppel-like transcription factor involved in lymphocyte development during normal haematopoiesis. Aberrant expression of BCL11A has been observed in several haematological malignancies, including chronic lymphocytic leukaemia (CLL). However, its functions in the regulatory networks of malignant B lymphocytes are poorly understood, as are the relations to clinical course and outcome of B-cell malignancies, particularly CLL. METHODS: The expression of BCL11A was analysed in peripheral blood mononuclear cells of 87 newly-diagnosed CLL patients by quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR), and association with clinical and molecular variables was assessed. RESULTS: BCL11A was significantly overexpressed in CLL samples compared to control samples (p < 0.001). BCL11A expression level exhibited no association with age, sex, leukocyte, lymphocyte and platelet counts, haemoglobin level, serum ß2-microglobulin, CD38 status and cytogenetic abnormalities. On the other hand, high BCL11A expression was associated with low serum lactate dehydrogenase (p = 0.031), Binet A stage (p = 0.047) and mutated IGHV (p = 0.028). In addition, a positive correlation with BCL2/BAX mRNA ratio was observed (r = 0.36; p < 0.001). Regarding the association with the time to first treatment (TTFT), a trend towards longer median TTFT in BCL11A high- versus BCL11A low-expressing cases was detected (21 vs. 6 months; p = 0.164). CONCLUSION: The results of this study show that BCL11A is upregulated in CLL patients, and that high BCL11A expression at diagnosis may be associated with better prognosis. These data are consistent with the role of BCL11A expression in CLL biology, and imply its potential prognostic relevance.

Frequent deletions of JARID2 in leukemic transformation of chronic myeloid malignancies.

Chronic myeloproliferative neoplasms (MPN) and myelodysplastic syndromes (MDS) have an inherent tendency to progress to acute myeloid leukemia (AML). Using high-resolution SNP microarrays, we studied a total of 517 MPN and MDS patients in different disease stages, including 77 AML cases with previous history of MPN (N = 46) or MDS (N = 31). Frequent chromosomal deletions of variable sizes were detected, allowing the mapping of putative tumor suppressor genes involved in the leukemic transformation process. We detected frequent deletions on the short arm of chromosome 6 (del6p). The common deleted region on 6p mapped to a 1.1-Mb region and contained only the JARID2 gene--member of the polycomb repressive complex 2 (PRC2). When we compared the frequency of del6p between chronic and leukemic phase, we observed a strong association of del6p with leukemic transformation (P = 0.0033). Subsequently, analysis of deletion profiles of other PRC2 members revealed frequent losses of genes such as EZH2, AEBP2, and SUZ12; however, the deletions targeting these genes were large. We also identified two patients with homozygous losses of JARID2 and AEBP2. We observed frequent codeletion of AEBP2 and ETV6, and similarly, SUZ12 and NF1. Using next generation exome sequencing of 40 patients, we identified only one somatic mutation in the PRC2 complex member SUZ12. As the frequency of point mutations in PRC2 members was found to be low, deletions were the main type of lesions targeting PRC2 complex members. Our study suggests an essential role of the PRC2 complex in the leukemic transformation of chronic myeloid disorders.

Clinical significance of genetic aberrations in secondary acute myeloid leukemia.

The study aimed to identify genetic lesions associated with secondary acute myeloid leukemia (sAML) in comparison with AML arising de novo (dnAML) and assess their impact on patients' overall survival (OS). High-resolution genotyping and loss of heterozygosity mapping was performed on DNA samples from 86 sAML and 117 dnAML patients, using Affymetrix Genome-Wide Human SNP 6.0 arrays. Genes TP53, RUNX1, CBL, IDH1/2, NRAS, NPM1, and FLT3 were analyzed for mutations in all patients. We identified 36 recurrent cytogenetic aberrations (more than five events). Mutations in TP53, 9pUPD, and del7q (targeting CUX1 locus) were significantly associated with sAML, while NPM1 and FLT3 mutations associated with dnAML. Patients with sAML carrying TP53 mutations demonstrated lower 1-year OS rate than those with wild-type TP53 (14.3% ± 9.4% vs. 35.4% ± 7.2%; P = 0.002), while complex karyotype, del7q (CUX1) and del7p (IKZF1) showed no significant effect on OS. Multivariate analysis confirmed that mutant TP53 was the only independent adverse prognostic factor for OS in sAML (hazard ratio 2.67; 95% CI: 1.33-5.37; P = 0.006). Patients with dnAML and complex karyotype carried sAML-associated defects (TP53 defects in 54.5%, deletions targeting FOXP1 and ETV6 loci in 45.4% of the cases). We identified several co-occurring lesions associated with either sAML or dnAML diagnosis. Our data suggest that distinct genetic lesions drive leukemogenesis in sAML. High karyotype complexity of sAML patients does not influence OS. Somatic mutations in TP53 are the only independent adverse prognostic factor in sAML. Patients with dnAML and complex karyotype show genetic features associated with sAML and myeloproliferative neoplasms.

Prognostic impact of NPM1 mutations in Serbian adult patients with acute myeloid leukemia.

Based on current findings, the presence of NPM1 mutations in acute myeloid leukemia (AML) patients is associated with an increased probability of complete remission (CR) and better overall survival (OS). We determined the incidence and prognostic relevance of NPM1 mutations, their association with FLT3 and IDH mutations, and other clinical characteristics in Serbian adult AML patients. Samples from 111 adult de novo AML patients, including 73 AML cases with a normal karyotype (NK-AML), were studied. NPM1, FLT3, and IDH mutations were detected by PCR and direct sequencing. NPM1 mutations were detected in 22.5% of patients. The presence of NPM1 mutations predicted a low CR rate and shorter OS. NPM1 mutations showed an association with both FLT3 and IDH mutations. Survival analysis based on NPM1/FLT3 mutational status revealed a lower OS for NPM1(+)/FLT3(-) compared to the NPM1(-)/FLT3(-) group in NK-AML patients. The lack of impact or unfavorable prognostic effect of NPM1 mutations found in this study can be assigned to a small cohort of analyzed AML patients, as can the presence of FLT3 and IDH mutations or other genetic lesions that cooperate with NPM1 mutations influencing prognosis.

Diagnostic and Therapeutic Implications of Long Non-Coding RNAs in Leukemia.

Leukemia is a heterogenous group of hematological malignancies categorized in four main types (acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), chronic myeloid leukemia (CML) and chronic lymphocytic leukemia (CLL). Several cytogenetic and molecular markers have become a part of routine analysis for leukemia patients. These markers have been used in diagnosis, risk-stratification and targeted therapy application. Recent studies have indicated that numerous regulatory RNAs, such as long non-coding RNAs (lncRNAs), have a role in tumor initiation and progression. When it comes to leukemia, data for lncRNA involvement in its etiology, progression, diagnosis, treatment and prognosis is limited. The aim of this review is to summarize research data on lncRNAs in different types of leukemia, on their expression pattern, their role in leukemic transformation and disease progression. The usefulness of this information in the clinical setting, i.e., for diagnostic and prognostic purposes, will be emphasized. Finally, how particular lncRNAs could be used as potential targets for the application of targeted therapy will be considered.

Expression Profiles of Long Non-Coding RNA GAS5 and MicroRNA-222 in Younger AML Patients.

Acute myeloid leukemia (AML) is a heterogeneous malignant disease both on clinical and genetic levels. AML has poor prognosis and, therefore, there is a constant need to find new prognostic markers, as well as markers that can be used as targets for innovative therapeutics. Recently, the search for new biomarkers has turned researchers' attention towards non-coding RNAs, especially long non-coding RNAs (lncRNAs) and micro RNAs (miRNAs). We investigated the expression level of growth arrest-specific transcript 5 (GAS5) lncRNA in 94 younger AML patients, and also the expression level of miR-222 in a cohort of 39 AML patients with normal karyotype (AML-NK), in order to examine their prognostic potential. Our results showed that GAS5 expression level in AML patients was lower compared to healthy controls. Lower GAS5 expression on diagnosis was related to an adverse prognosis. In the AML-NK group patients had higher expression of miR-222 compared to healthy controls. A synergistic effect of GAS5low/miR-222high status on disease prognosis was not established. This is the first study focused on examining the GAS5 and miR-222 expression pattern in AML patients. Its initial findings indicate the need for further investigation of these two non-coding RNAs, their potential roles in leukemogenesis, and the prognosis of AML patients.

Prognostic significance of combined BAALC and MN1 gene expression level in acute myeloid leukemia with normal karyotype.

INTRODUCTION: Acute myeloid leukemia with normal karyotype (AML-NK) is the largest group of AML patients with very heterogeneous disease outcome. In order to ensure more precise risk stratification new molecular markers have been introduced, like expression level for BAALC (Brain and Acute Leukemia, Cytoplasmic) and MN1 (Meningioma 1) genes. METHODS: In this study, we investigated expression level of both genes in 111 adult AML-NK at diagnosis and examined their prognostic potential. RESULTS: BAALC and MN1 expression were detected in about one third of the patients, and positive correlation between these two genes was found. The BAALC+ /or MN1+ status was not associated with the presence of FLT3-ITD mutations, but exhibited strong correlation with NPM1wt status (P < .001). Therefore, among BAALC+ /or MN1+ patients the most frequent ones were FLT3-ITD- /NPM1- double negative patients with intermediate prognosis. When BAALC+ /or MN1+ patients were divided into BAALChigh /BAALClow (21/21) and MN1high /MN1low (21/22) groups, we detected that BAALChigh /or MN1high patients had a tendency toward lower complete remission rate. Also, survival analysis showed that BAALChigh /or MN1high patients had shorter disease-free survival and overall survival (OS). The most pronounced influence on prognosis was detected in FLT3-ITD- /NPM1- group of patients that are lacking reliable prognostic markers, where OS in BAALChigh /or MN1high was only 5 months vs 25 months in BAALClow /or MN1low . CONCLUSION: These findings indicate that BAALC and MN1 expression level could be used for more precise risk stratification of AML-NK patients and especially FLT3-ITD- /NPM1- patients, transforming this intermediate-risk group, into a group with an adverse prognosis.

Novel transcriptional regulatory element in the phenylalanine hydroxylase gene intron 8.

We present the first transcriptional regulatory element found in a PAH gene intron. The element is located in the PAH gene intron 8, acts as an enhancer specifically in the hepatoma cell line, and binds GATA-1 transcription factor. Herein the presented data could unlock a new area for the analysis of PAH gene expression and could contribute to refining genotype-phenotype correlation.

Thalassemia syndromes in Serbia: an update.

Thalassemia syndromes constitute a group of genetic disorders, widespread throughout the world. The present study contains data on thalassemia syndromes and their chromosomal environment obtained in Serbia over a period of 10 years. Ten different ß-thalassemia (ß-thal) mutations and two hemoglobin (Hb) variants were detected in 127 members of 68 families. Hb Lepore-Boston-Washington (Lepore-BW) (δ87Gln-ß-IVS-II-8), a thalassemic Hb variant, was shown to be the most common cause of thalassemia in Serbia. Haplotype analyses of the ß-globin gene clusters of healthy individuals as well as of individuals affected with ß-thal showed that haplotype I was the most frequent haplotype in the Serbian population, followed by haplotypes II and IX. Two novel haplotypes were detected. Haplotype analyses showed the association between certain haplotypes and the most common thalassemic mutations. Results presented in this paper will update the Serbian national mutation database and contribute to a better understanding of genographic history of South European and Balkan populations.

Expression Pattern and Prognostic Significance of EVI1 Gene in Adult Acute Myeloid Leukemia Patients with Normal Karyotype.

According to current criteria, patients with acute myeloid leukemia with normal karyotype (AML-NK) are classified as intermediate risk patients. There is a constant need for additional molecular markers that will help in substratification into more precise prognostic groups. One of the potential new markers is Ecotropic viral integration 1 site (EVI1) transcriptional factor, whose expression is dissregulated in abnormal hematopoietic process. The purpose of this study was to examine EVI1 gene expression in 104 adult AML-NK patients and on 10 healthy bone marrow donors using real-time polymerase chain reaction method, and to evaluate association between EVI1 expression level and other molecular and clinical features, and to examine its potential influence on the prognosis of the disease. Overexpression of EVI1 gene (EVI1 + status) was present in 17% of patients. Increased EVI1 expression was predominantly found in patients with lower WBC count (P = 0.003) and lower bone marrow blast percentage (P = 0.005). EVI1 + patients had lower WT1 expression level (P = 0.041), and were negative for FLT3-ITD and NPM1 mutations (P = 0.036 and P = 0.003). Patients with EVI1 + status had higher complete remission rate (P = 0.047), but EVI1 expression didn't influence overall and disease free survival. EVI1 expression status alone, cannot be used as a new marker for more precise substratification of AML-NK patients. Further investigations conducted on larger number of patients may indicate how EVI1 expression could influence the prognosis and outcome of AML-NK patients, by itself, or in the context of other molecular and clinical parameters.

Complex transcriptional regulation of the BCL2L12 gene: Novel, active promoter in K562 cells.

The BCL2L12, one of the latest discovered members of the BCL2 family, has both pro- and anti-apoptotic roles that are cell-type-dependent. Its role in tumorigenesis is highly implicated. Sixty-three splice variants of this gene have been identified so far, with significant differences in expression patterns between various cancer cell lines. Presently, little is known regarding the regulation of expression of the BCL2L12 gene. For the vast majority of BCL2L12 gene splice variants, the 5'- and 3'-untranslated regions as well as their transcriptional regulation have not been determined yet. The aim of this study was to get insight into the regulation of the BCL2L12 gene transcription in human chronic myelogenous leukemia (K562) cell line. Our results point to the activity of novel transcription start site of the BCL2L12 gene and indicate that Sp1 and GATA-1 transcription factors could be involved in the regulation of BCL2L12 gene expression in K562 cells. The previously reported active promoter of BCL2L12 gene differs from the one we described in our study. If this novel BCL2L12 promoter is confirmed to be active in other malignancies, transcripts generated from this region could be considered as new cancer-specific biomarkers. The results of our study contribute to the better understanding of the transcriptional regulation of the BCL2L12 gene.