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INTRODUCTION: Both microenvironmental signals from surrounding cells and changes in the genome of leukemic cells play essential role in the development of chronic lymphocytic leukemia. Nurse-like cells (NLCs) are one of the important elements of the microenvironment of CLL cells. The key role in the interactions of leukemic cells with NLCs is played by chemokines, which may interfere with the programmed cell death process in the leukemic lymphocytes. The aim of our study was analysis of selected microenvironmental factors having a potential impact on the leukemic cells survival, as well as their association with clinical, cytogenetic, and molecular parameters. For this study, we selected three types of molecules which can modulate microenvironment: chemokines IL-8 and CCL3 (which are classically secreted to extracellular matrix), soluble forms of adhesion molecules JAG1 and CD163, and secreted form of endogenous protein BIRC5. We assessed their expression in the serum of CLL patients as well as in medium of long-term NLCs cultures. METHODS: Long-term cell culture was prepared from mononuclear cells derived from the blood of 34 patients with CLL. Number of NLCs cells was evaluated, under a light inverted microscope. The concentration of IL-8, CCL3, sBIRC5, sCD163, and sJAG1 in culture medium and serum was assessed by enzyme-linked immunosorbent assays. RESULTS: There were significant differences in the concentration of IL-8, sBIRC5, CCL3, sCD163, and sJAG1 between the patient's blood serum and the culture medium. The concentrations of IL-8, CCL3, and JAG1 were higher in the culture medium, which confirmed the role of the microenvironment in the production of these proteins. In addition, the concentration of CCL3 chemokine in both patient's blood serum and in the culture medium correlated with the number of NLCs and with known prognostic factors in the course of CLL, e.g., Rai stage, WBC, expression of ZAP-70, CD38, and CD5/19. CONCLUSION: The microenvironment of CLL cells, which includes NLCs, plays an important role in the pathogenesis of CLL. The CCL3 chemokine seems to be a good factor representing microenvironment of CLL cells. Chronic lymphocytic leukemia is a complex and very heterogeneous disease; therefore, its progress should be considered both in the context of genetic changes and the interaction with microenvironmental cells.
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Leucemia Linfocítica Crônica de Células B , Humanos , Quimiocina CCL3/genética , Quimiocina CCL3/metabolismo , Ensaio de Imunoadsorção Enzimática , Interleucina-8 , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/metabolismo , Prognóstico , Microambiente Tumoral/genéticaRESUMO
Pre-eclampsia is a placenta-related complication occurring in 2-10% of all pregnancies. miRNAs are a group of non-coding RNAs regulating gene expression. There is evidence that C19MC miRNAs are involved in the development of the placenta. Deregulation of chromosome 19 microRNA cluster (C19MC) miRNAs expression leads to impaired cell differentiation, abnormal trophoblast invasion and pathological angiogenesis, which can lead to the development of pre-eclampsia. Information was obtained through a review of articles available in PubMed Medline. Articles on the role of the C19MC miRNA in the development of pre-eclampsia published in 2009-2022 were analyzed. This review article summarizes the current data on the role of the C19MC miRNA in the development of pre-eclampsia. They indicate a significant increase in the expression of most C19MC miRNAs in placental tissue and a high level of circulating fractions in serum and plasma, both in the first and/or third trimester in women with PE. Only for miR-525-5p, low levels of plasma expression were noted in the first trimester, and in the placenta in the third trimester. The search for molecular factors indicating the development of pre-eclampsia before the onset of clinical symptoms seems to be a promising diagnostic route. Identifying women at risk of developing pre-eclampsia at the pre-symptomatic stage would avoid serious complications in both mothers and fetuses. We believe that miRNAs belonging to cluster C19MC could be promising biomarkers of pre-eclampsia development.
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MicroRNAs , Pré-Eclâmpsia , Feminino , Humanos , Gravidez , Pré-Eclâmpsia/metabolismo , Placenta/metabolismo , MicroRNAs/metabolismo , Trofoblastos/metabolismo , Primeiro Trimestre da GravidezRESUMO
Expression of microRNAs is altered in cancer. Circulating miRNA level assessed in body fluids commonly reflects their expression in tumor cells. In leukemias, however, both leukemic and nonleukemic cells compose circulating miRNA expression profile of peripheral blood. The latter contribution to extracellular miRNA pool may result in specific microenvironmental signaling, which promotes proliferation and survival. In our study, we used qT-PCR to assay peripheral blood serum of 22 chronic lymphocytic leukemia (CLL) patients for the expression of 84 miRNAs associated with activation and differentiation of B and T lymphocytes. Results were analyzed regarding the most important prognostic factors. We have found that the general expression of examined miRNAs in CLL patients was lower as compared to healthy volunteers. Only miR-34a-5p, miR31-5p, miR-155-5p, miR-150-5p, miR-15a-3p, and miR-29a-3p were expressed on a higher level. Alterations of expression observed in CLL patients involved miRNAs associated both with B and T lymphocyte differentiation and activation. The most important discriminating factors for all functional miRNA groups were trisomy 12, CD38 expression, B2M level, WBC, and NOTCH1 gene mutation. Correlation of expression of miRNAs related to T lymphocytes with prognostic factors proves their supportive function in a leukemic microenvironment. Further studies utilizing a larger test group of patients may warrant the identification of circulating miRNAs that are key players in intercellular interactions and should be considered in the design of microenvironment-targeted therapies.
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Linfócitos B/fisiologia , Diferenciação Celular/fisiologia , Regulação Neoplásica da Expressão Gênica , Leucemia Linfocítica Crônica de Células B/sangue , MicroRNAs/sangue , Linfócitos T/fisiologia , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Células Cultivadas , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/genética , Masculino , MicroRNAs/biossíntese , MicroRNAs/genética , Pessoa de Meia-IdadeRESUMO
B-cell chronic lymphocytic leukemia (B-CLL) is one of the most common hematologic malignancies in Western countries. Accumulation of leukemic lymphocytes in peripheral blood, bone marrow and secondary lymphatic organs of CLL patients is due to decreased apoptosis rather than to increased proliferation. The former is driven by signals from a specific microenvironment, created by stromal cells of mesenchymal origin, follicular dendritic cells, T lymphocytes and others. Nurse-like cells (NLCs) were first described to differentiate from peripheral blood mononuclear cells of CLL patients in vitro, then they have been also found in proliferation centers of their lymphatic tissues. Like tumor-associated macrophages (TAMs) in solid tumors, nurse-like cells promote survival of CLL lymphocytes. NLC gene expression patterns suggest their similarity to TAMs and differ between patients depending on ZAP70 protein expression status. NLC number in vitro corresponds with CD14 expressing cell count and beta-2-microglobulin serum level, and positively correlates with leukemic lymphocyte viability. As NLCs strongly express genes for adhesion molecules and secrete chemokines of antiapoptotic activity, they should be considered as a target for anti-microenvironment therapy of this incurable disease.
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Leucemia Linfocítica Crônica de Células B/patologia , Macrófagos/patologia , Microambiente Tumoral , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Feminino , Regulação Leucêmica da Expressão Gênica , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/mortalidade , Contagem de Leucócitos , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fagocitose/imunologia , Prognóstico , Transcriptoma , Microambiente Tumoral/genética , Microambiente Tumoral/imunologiaRESUMO
MicroRNAs (miRNAs) are a class of small non-coding, single-stranded RNAs (ribonucleic acids) that play important roles in many vital processes through their impact on gene expression. One such miRNA, miR210, represents a hypoxia-induced cellular miRNA group that hold a variety of functions. This review article highlights the importance of miR-210 in the development of pre-eclampsia.KEY MESSAGEmiR-210 is a promising biomarker for monitoring pregnancy with pre-eclampsia. Overexpression of miR-210 had a negative impact on the process of cell migration and trophoblast invasion.
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MicroRNAs , Pré-Eclâmpsia , Movimento Celular/genética , Feminino , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/genética , Gravidez , Trofoblastos/metabolismoRESUMO
Preeclampsia and hypertension complicate several pregnancies. Identifying women at risk of developing these conditions is essential to establish potential treatment modalities. Biomarkers such as C19MC microRNA in pregnant patients wopuld assist in defining pregnancy surveillance and implementing interventions. This study sought to analyze circulating C19MC microRNA as an early marker of hypertension and preeclampsia in pregnant patients. A systematic review was undertaken using the following registers: disease registries, pregnancy registries, and pregnancy exposure registries, and the following databases: PubMed, CINAHL, Web of Science, Scopus, and EMBASE. The risk of bias was assessed using the Cochrane technique. From the 45 publications retrieved from the registers and databases, only 21 were included in the review after the removal of duplicates, screening, and eligibility evaluation. All 210 publications had a low risk of bias and illuminated the potential use of circulating C19MC microRNA as an early marker of hypertension and preeclampsia in pregnant patients. Therefore, it was concluded that C19MC microRNA can be used as an early marker of gestational preeclampsia and hypertension.
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(1) Background: The aim of our study was the complex assessment of WT1 variants and their expression in relation to chromosomal changes and molecular prognostic markers in acute myeloid leukemia (AML). It is the first multidimensional study in Polish AML patients; (2) Methods: Bone marrow aspirates of 90 AML patients were used for cell cultures (banding techniques and fluorescence in situ hybridization), and to isolate DNA (WT1 genotyping, array comparative genomic hybridization), and RNA (WT1 expression). Peripheral blood samples from 100 healthy blood donors were used to analyze WT1 rs16754; (3) Results: Allele frequency and distribution of WT1 variant rs16754 (A;G) did not differ significantly among AML patients and controls. Higher expression of WT1 gene was observed in AA genotype (of rs16754) in comparison with GA or GG genotypes10,556.7 vs. 25,836.5 copies (p = 0.01), respectively. WT1 mutations were more frequent in AML patients under 65 years of age (p < 0.0001) and affected relapse-free survival (RFS). The presence of NPM1 or CEBPA mutations decreased the risk of WT1 mutation presence, odds ratio (OR) = 0.11, 95% CI 0.02−0.46, p = 0.002 or OR = 0.05, 95% CI 0.006−0.46, p = 0.002, respectively. We observed significantly higher WT1 expression in AML CD34+ vs. CD34−, −20,985 vs. 8304 (p = 0.039), respectively. The difference in WT1 expression between patients with normal and abnormal karyotype was statistically insignificant; (4) Conclusions: WT1 gene expression and its rs16754 variant at diagnosis did not affect AML outcome. WT1 mutation may affect RFS in AML.
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Acute myeloid leukemia (AML) constitutes a group of diseases that are very heterogeneous with regard to clinical course, response to therapy as well as cytogenetic aberrations and gene mutations. Such lesions are of prognostic value. Patients with t(8;21), inv(16)/t(16;16) or t(15;17) have a favorable prognosis. Patients with normal karyotype and aberrations +6, +8 Y, t(9;11) and del(12p) are classified in the group of intermediate prognosis. In the case of patients with complex karyotype or with the aberrations inv(3)/t(3;3), t(6;9), 5, 7, del(5q), del(7q) and 11q23 rearrangements, the prognosis is poor. Unfavorable molecular factors include C-MYC amplification, MLL amplification and rearrangement, FLT3-ITD, WT1 mutation and overexpression of BAALC, ERG or MN1. The changes in miRNA expression may also be important for AML prognosis. That is why the cases with normal karyotype (CN-AML) and cases with complex aberrations remain to be better characterized at the genetic level. Array technology enables the analysis of genomic DNA and gene expression. This approach may be used in the search for new prognostic and predictive markers in AML.
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Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Mutação , Aberrações Cromossômicas , Humanos , PrognósticoRESUMO
Isochromosome 17q [i(17q)] with its two identical long arms is formed by duplication of the q arm and loss of the short p arm. The breakpoint in chromosome 17 that allows the formation of this isochromosome is located at 17p11.2, and the ~240 kb region with its large, palindromic, low-copy repeat sequences are present here. The region is highly unstable and susceptible to a variety of genomic alterations which may be induced by or without toxic agents. One molecular consequence of i(17q) development is the obligatory loss of a single TP53 allele of the tumor suppressor P53 protein located at 17p13.1. Isochromosome 17q is involved in cancer development and progression. It occurs in combination with other chromosomal defects (complex cytogenetics), and rarely as a single mutation. The i(17q) rearrangement has been described as the most common chromosomal aberration in primitive neuroectodermal tumors and medulloblastomas. This isochromosome is also detected in different hematological disorders. In this article, we analyze literature data on the presence of i(17q) in proliferative disorders of the hematopoietic system in the context of its role as a prognostic factor of disease progression. The case reports are added to support the presented data. Currently, there are no indications for the use of specific treatment regimens in the subjects with a presence of the isochromosome 17q. Thus, it is of importance to continue studies on the prognostic role of this abnormality and even single cases should be reported as they may be used for further statistical analyses or meta-analyses.
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Chronic lymphocytic leukemia (CLL) is one of the most frequent lymphoproliferative diseases. CLL is characterized by unusual heterogeneity, which probably reflects its biological and genetic lack of homogeneity. Clonal chromosome aberrations belong to the most important prognostic and predictive factors in CLL. This research was aimed at observing clonal evolution in CLL at the chromosomal level, and assessing its clinical significance in relation to selected prognostic factors. The study involved 72 untreated patients with CLL. The preliminary investigations using cytogenetic banding analysis (CBA) and FISH were performed at the time of diagnosis, and again after about 24 months to observe clonal changes (clonal evolution). In addition, other parameters were evaluated, i.e., the expression of ZAP-70 kinase, CD38 antigen, and the mutation statuses of IGVH and NOTCH1 genes. Classic prognostic factors, i.e., categorized ZAP70 and CD38 expressions as well as mutations in IGVH and NOTCH1 genes did not influence the course of clonal evolution in the examined group of patients. Clonal evolution was detected in 45.8% of patients by means of CBA, and in 19.4% patients with FISH. Analysis of chromosomal aberrations in the examined group of patients showed that the incidence of 17p deletions and translocations in karyotypes has a negative impact on overall survival. CE was found to be a risk factor for the occurrence of disease progression (OR = 2.22). Our observations indicate that combined CBA and FISH are the most optimal techniques for monitoring clonal evolution in the course of CLL.
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Evolução Clonal/genética , Leucemia Linfocítica Crônica de Células B/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Aberrações Cromossômicas , Bandeamento Cromossômico , Progressão da Doença , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariótipo , Leucemia Linfocítica Crônica de Células B/mortalidade , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Taxa de SobrevidaRESUMO
Conventional cytogenetics is invariably one of the most important methods used in diagnostics of chronic lymphoproliferations. It complements fluorescence in situ hybridization (FISH) and molecular analysis. Presence of particular chromosomal alterations in chronic lymphocytic leukemia enables patients' stratification into appropriate cytogenetic risk groups and influences treatment decisions. In other non-Hodgkin lymphomas cytogenetic analyses are employed also in minimal residual disease assessment.As lymphocytes in chronic lymphoid malignancies are characterized by low proliferation rate in vitro, it is critical to induce their division in the culture properly. Here, we describe methods of lymphocyte isolation from patient's samples, conditions of cell culture, and the most commonly used mitogens for B- and T-lymphocytes in hemato-oncologic analyses.
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Aberrações Cromossômicas , Análise Citogenética , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/genética , Biópsia , Medula Óssea/patologia , Técnicas de Cultura de Células , Bandeamento Cromossômico/métodos , Análise Citogenética/métodos , Humanos , Linfonodos/patologia , Células Tumorais CultivadasRESUMO
INTRODUCTION: Significant and accessible predictive factors for bortezomib treatment in plasma cell myeloma (PCM) are still lacking. TP53 codon 72 polymorphism (P72R) results in proline (P) or arginine (R) at 72 amino acid position, which causes synthesis of proteins with distinct functions. The aims of our study were to: 1) analyze whether this polymorphism is associated with an increased risk of PCM; 2) study whether the P72R polymorphism affects overall survival (OS) among PCM patients; 3) assess the possible association of the P72R polymorphism with sensitivity to bortezomib in cell cultures derived from PCM patients. MATERIAL AND METHODS: Genomic DNA from newly diagnosed 59 patients (without IgVH gene rearrangements and TP53 deletions) and 50 healthy blood donors were analyzed by RFLP-PCR to identify TP53 polymorphism. Chromosomal aberrations were detected by use of cIg-FISH. The lymphocyte cell cultures from a subgroup of 40 PCM patients were treated with bortezomib (1, 2 and 4 nM). RESULTS: The P allele of the P72R polymorphism was more common than the R allele in PMC patients compared to controls (39% vs. 24%), and the difference was significant (p = 0.02). The PP and PR genotypes (in combina-tion) were more frequent among cases than in controls (65% vs. 42%, OR = 2.32, p = 0.04). At the cell culture level and 2 nM bortezomib concentration the PP genotype was associated with higher necrosis rates (10.5%) compared to the PR genotype (5.7%, p = 0.006) or the RR genotype (6.3%, p = 0.02); however, no effect of genotypes was observed at bortezomib concentrations of 1 and 4 nM. The shortest OS (12 months) was observed in patients with the PP genotype compared to patients with the PR or RR genotypes (20 months) (p = 0.04). CONCLUSIONS: The results suggest that P72R polymorphisms may be associated with an increased PCM risk and may affect OS of PCM patients. However, we saw no consistent results of the polymorphism effect on apoptosis and necrosis in cell cultures derived from PCM patients. Further studies are need in this regard.
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Mieloma Múltiplo/genética , Plasmócitos/patologia , Polimorfismo Genético , Proteína Supressora de Tumor p53/genética , Idoso , Antineoplásicos/uso terapêutico , Apoptose , Bortezomib/uso terapêutico , Feminino , Humanos , Masculino , Mieloma Múltiplo/tratamento farmacológicoRESUMO
One of the research methods of prognostic value in chronic lymphocytic leukemia (CLL) is cytogenetic analysis. This method requires the presence of appropriate B-cell mitogens in cultures in order to obtain a high mitotic index. The aim of our research was to determine the most effective methods of in vitro B-cell stimulation to maximize the number of metaphases from peripheral blood cells of patients with CLL for classical cytogenetic examination, and then to correlate the results with those obtained using fluorescence in situ hybridization (FISH). The study group involved 50 consecutive patients with CLL. Cell cultures were maintained with the basic composition of culture medium and addition of respective stimulators. We used the following stimulators: Pokeweed Mitogen (PWM), 12-O-tetradecanoylphorbol 13-acetate (TPA), ionophore, lipopolysaccharide (LPS), and CpG-oligonucleotide DSP30. We received the highest mitotic index when using the mixture of PWM+TPA+I+DSP30. With classical cytogenetic tests using banding techniques, numerical and structural aberrations of chromosomes were detected in 46 patients, and no change was found in only four patients. Test results clearly confirmed the legitimacy of using cell cultures enriched with the mixture of cell stimulators and combining classical cytogenetic techniques with the FISH technique in later patient diagnosing.
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Aberrações Cromossômicas , Análise Citogenética/métodos , Hibridização in Situ Fluorescente/métodos , Leucemia Linfocítica Crônica de Células B/genética , Linfócitos/metabolismo , Mitógenos/farmacologia , Idoso , Idoso de 80 Anos ou mais , Células Cultivadas , Feminino , Humanos , Linfócitos/efeitos dos fármacos , Masculino , Metáfase/efeitos dos fármacos , Pessoa de Meia-Idade , Índice MitóticoRESUMO
INTRODUCTION: Acute myeloid leukemia (AML) is a genetically heterogeneous disease at both the cytogenetic and molecular levels. In AML cells many chromosomal aberrations are observed, some of them being characteristic of a particular subtype of patients, and others being less significant. Besides chromosomal abnormalities, the leukemic cells can have a variety of mutations involving individual genes. The aim of this work was to investigate the frequencies of molecular alterations with the focus on FLT3-ITD and NPM1 mutations in AML patients of different age groups living in a southeastern region of Poland. MATERIAL AND METHODS: The study group comprised 50 consecutive AML patients. We analyzed bone marrow samples by conventional cytogenetics. Cytogenetic evaluation in selected cases was complemented by the FISH technique. The internal tandem mutation in the FLT3 gene was identified using polymerase chain reaction (PCR), and the NPM1 mutation was assessed by direct nucleotide sequencing. RESULTS: The studies using classical cytogenetics showed chromosomal aberrations in 32 (64%) patients. In 18 cases no changes in the karyotype were found by conventional karyotyping. FLT3-ITD mutation was detected in 4 (8%) patients and mutation of NPM1 in 3 patients with AML (6%). CONCLUSIONS: The incidence of both mutations in our study group was lower than described elsewhere. We have confirmed that FLT3-ITD occurred more commonly in older patients and it was associated with shorter overall survival. By contrast, mutation of exon 12 of the NPM1 gene seems to be a good prognostic factor in AML patients with normal karyotype.
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Antioxidant compounds such as glutathione and its enzymes have become the focus of attention of medical sciences. Glutathione, a specific tripeptide, is involved in many intercellular processes. The glutathione concentration is determined by the number of GAG repeats in gamma-glutamylcysteine synthetase. GAG polymorphisms are associated with an increased risk of schizophrenia, berylliosis, diabetes, lung cancer, and nasopharyngeal tumors. Cancer cells with high glutathione concentration are resistant to chemotherapy treatment. The oxidized form of glutathione is formed by glutathione peroxidases (GPXs). The changes in activity of GPX1, GPX2, and GPX3 isoforms may be associated with the development of cancers, for example, prostate cancer or even colon cancer. Detoxification of glutathione conjugates is possible due to activity of glutathione S-transferases (GSTs). Polymorphisms in GSTM1, GSTP1, and GSTO1 enzymes increase the risk of developing breast cancer and hepatocellular carcinoma. Gamma-glutamyl transpeptidases (GGTs) are responsible for glutathione degradation. Increased activity of GGT correlates with adverse prognosis in patients with breast cancer. Studies on genes encoding glutathione enzymes are continued in order to determine the correlation between DNA polymorphisms in cancer patients.
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Predisposição Genética para Doença/genética , Glutationa/genética , Neoplasias Hematológicas/enzimologia , Neoplasias Hematológicas/genética , Polimorfismo Genético/genética , Genótipo , Humanos , Fatores de RiscoRESUMO
In a group of 75 untreated patients with a typical B cell chronic lymphocytic leukaemia (B-CLL) (CD19+, CD5/CD19+, CD23/CD19+), the frequency and clinical significance of TP53 gene deletion and chromosome 12 trisomy were assessed. The studies of peripheral blood lymphocytes were conducted using interphase in situ hybridization technique. Clonality was identified when TP53 deletion or chromosome 12 trisomy was found in at least 10% of cells. From all 75 examined patients 32 individuals without any of the genetic aberrations were analyzed (Group I) and 30 subjects with TP53 deletion (Group II) were chosen. In the other 13 patients, discussed in the next paper, either chromosome 12 trisomy (Group III--seven subjects) or both chromosome 12 trisomy and TP53 deletion (Group IV--six subjects) were found. In the Group I, there has been no further contact with three patients, while in the Group II--with two individuals. In the Group I, one patient of 29 in the study (3%) died after 84 months (seven years) from the diagnosis, whereas in the Group II--nine subjects of 28 in the study (32%) died within 1-36 months from the diagnosis. In three of those patients in the terminal condition, cytogenetic studies were repeated revealing an increase of approximately 5% in the percentage of peripheral blood cells with TP53 deletion. The frequent presence of TP53 deletion detected in 48% of patients is surprising. It is generally thought that the aberration is found in 10-15% of clinical cases. The studies should be confirmed on a larger group of patients.
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Cromossomos Humanos Par 12 , Deleção de Genes , Genes p53 , Leucemia Linfocítica Crônica de Células B/genética , Trissomia , Idoso , Idoso de 80 Anos ou mais , Análise Citogenética , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-IdadeRESUMO
Among 75 untreated patients with typical (CD19+, CD5/CD19+, CD23/CD19+) B-cell chronic lymphocytic leukemia (B-CLL) cytogenetic aberrations of peripheral blood cells were evaluated, using fluorescence in situ hybridization techniques. Two cytogenetic aberrations were evaluated: trisomy 12 and TP53 deletion. The clonality was determined when > or = 10% of the cells had of trisomy 12 or deletion TP53 gene. Trisomy 12 in 7 patients was detected, while trisomy 12 and TP53 deletion simultaneously in 6 patients were present. If the first group will be linked to the second one then 13 patients among 75 (17%) will have trisomy 12. In group of patients with trisomy 12 and TP53 deletion percentage of cells with trisomy 12 was almost two time more compare to patients with trisomy 12 as a single aberration. It is possible, that TP53 deletion ("the guardian of the genome") facilitates proliferation clones with others genomic aberrations. In two patients with trisomy 12 control cytogenetic study was performed. Increase of percentage cells with trisomy 12 for 8% and 30% respectively was detected. However, proliferation of cells with TP53 deletion was observed too. Clinical course of B-CLL in group of patient with trisomy 12, trisomy 12 and TP53 deletion simultaneously is more aggressive compared to the course of disease of patients with no cytogenetic aberrations (patients of Group I from Part I of paper). Frequency of IGHV gain mutation occurrence was not analyzed in both groups of patients. But trisomy 12 together with unmutated IGHV gene is found by some authors. The absence IGHV gene mutation is independent unfavourable prognostic factor.