Browsing by Author "Glumac, Irena (55541082300)"

Background: In chronic lymphocytic leukemia (CLL), in vivo apoptotic resistance of malignant B lymphocytes results, in part, from the intrinsic defects of their apoptotic machinery. These include genetic alterations and aberrant expression of many apoptosis regulators, among which the Bcl2 family members play a central role. Aim: The aim of this study was to investigate the association of pro-apoptotic Bax gene expression and Bcl2/Bax ratio with the clinical features of CLL patients as well as with molecular prognostic markers, namely the mutational status of rearranged immunoglobulin heavy variable (IGHV) genes and lipoprotein lipase (LPL) gene expression. Methods: We analyzed the expression of Bax mRNA and Bcl2/Bax mRNA ratio in the peripheral blood mononuclear cells of 58 unselected CLL patients and 10 healthy controls by the quantitative reverse-transcriptase polymerase chain reaction. Results: We detected significant Bax gene overexpression in CLL samples compared to non-leukemic samples (p=0.003), as well as an elevated Bcl2/Bax ratio (p=<0.001). Regarding the association with prognostic markers, the Bcl2/Bax ratio showed a negative correlation to lymphocyte doubling time (r=-0.307; p=0.0451), while high-level Bax expression was associated with LPL-positive status (p=0.035). Both the expression of Bax and Bcl2/Bax ratio were higher in patients with unmutated vs. mutated IGHV rearrangements, but this difference did not reach statistical significance. Conclusions: Our results suggest that dysregulated expression of Bcl2 and Bax, which leads to a high Bcl2/Bax ratio in leukemic cells, contributes to the pathogenesis and clinical course of CLL.

Background: In chronic lymphocytic leukemia (CLL), in vivo apoptotic resistance of malignant B lymphocytes results, in part, from the intrinsic defects of their apoptotic machinery. These include genetic alterations and aberrant expression of many apoptosis regulators, among which the Bcl2 family members play a central role. Aim: The aim of this study was to investigate the association of pro-apoptotic Bax gene expression and Bcl2/Bax ratio with the clinical features of CLL patients as well as with molecular prognostic markers, namely the mutational status of rearranged immunoglobulin heavy variable (IGHV) genes and lipoprotein lipase (LPL) gene expression. Methods: We analyzed the expression of Bax mRNA and Bcl2/Bax mRNA ratio in the peripheral blood mononuclear cells of 58 unselected CLL patients and 10 healthy controls by the quantitative reverse-transcriptase polymerase chain reaction. Results: We detected significant Bax gene overexpression in CLL samples compared to non-leukemic samples (p=0.003), as well as an elevated Bcl2/Bax ratio (p=<0.001). Regarding the association with prognostic markers, the Bcl2/Bax ratio showed a negative correlation to lymphocyte doubling time (r=-0.307; p=0.0451), while high-level Bax expression was associated with LPL-positive status (p=0.035). Both the expression of Bax and Bcl2/Bax ratio were higher in patients with unmutated vs. mutated IGHV rearrangements, but this difference did not reach statistical significance. Conclusions: Our results suggest that dysregulated expression of Bcl2 and Bax, which leads to a high Bcl2/Bax ratio in leukemic cells, contributes to the pathogenesis and clinical course of CLL.

Dysregulation of apoptosis is a distinctive feature of chronic lymphocytic leukemia (CLL), although a unique mechanism underlying apoptosis resistance of CLL B lymphocytes has not been identified yet. Aberrant expression as well as genetic and epigenetic alterations of numerous genes involved in different pathways of apoptosis regulation has been described in CLL. Here, we report the expression analysis of Bcl2L12 (Bcl2-like 12), a novel apoptotic gene belonging to Bcl2 family, in 58 Serbian CLL patients. Quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) analysis revealed a significant overexpression of Bcl2L12 mRNA in CLL samples compared to non-leukemic samples, implying its role in the pathogenesis of the disease. Receiver operating characteristic (ROC) analysis showed that Bcl2L12 expression efficiently discriminates CLL cases from healthy controls. However, relatively homogenous Bcl2L12 mRNA expression among patients did not reflect their clinical characteristics (with the exception of lactate dehydrogenase status and time from diagnosis to treatment) and failed to show association with the most informative prognostic markers, namely the mutational status of rearranged immunoglobulin heavy chain variable region genes, CD38 and lipoprotein lipase gene (LPL) expression. © 2013 Springer Science+Business Media New York.

Dysregulation of apoptosis is a distinctive feature of chronic lymphocytic leukemia (CLL), although a unique mechanism underlying apoptosis resistance of CLL B lymphocytes has not been identified yet. Aberrant expression as well as genetic and epigenetic alterations of numerous genes involved in different pathways of apoptosis regulation has been described in CLL. Here, we report the expression analysis of Bcl2L12 (Bcl2-like 12), a novel apoptotic gene belonging to Bcl2 family, in 58 Serbian CLL patients. Quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) analysis revealed a significant overexpression of Bcl2L12 mRNA in CLL samples compared to non-leukemic samples, implying its role in the pathogenesis of the disease. Receiver operating characteristic (ROC) analysis showed that Bcl2L12 expression efficiently discriminates CLL cases from healthy controls. However, relatively homogenous Bcl2L12 mRNA expression among patients did not reflect their clinical characteristics (with the exception of lactate dehydrogenase status and time from diagnosis to treatment) and failed to show association with the most informative prognostic markers, namely the mutational status of rearranged immunoglobulin heavy chain variable region genes, CD38 and lipoprotein lipase gene (LPL) expression. © 2013 Springer Science+Business Media New York.

Within a personalized treatment approach in multiple myeloma (MM), the prognostic significance of cereblon (CRBN) expression was analyzed in 92 newly diagnosed patients. In patients treated with thalidomide-based combinations, CRBN expression significantly affected the treatment response (P = .028) and progression-free survival (P = .017). With implications for the treatment outcome, measurement of CRBN expression might represent an additional prognostic tool in a personalized treatment approach. Background To personalize the treatment approach for patients with multiple myeloma (MM), molecular markers such as cereblon (CRBN) are currently the focus of investigation. The aim of the present study was to test the prognostic significance of CRBN expression in MM patients ineligible for autologous stem cell transplantation (ASCT). Patients and Methods The data from 92 previously untreated patients were analyzed. The distribution according to the International Staging System score was 26.1%, 30.4%, and 43.5% with a score of 1, 2, and 3, respectively. Thalidomide- and bortezomib-based combinations were used in 83.7% and 16.3% of the patients, respectively. Results A treatment response (complete remission, very good partial remission, partial remission) was achieved in 83.7% of the patients and correlated with high CRBN expression (P = .006), mainly in the patients treated with thalidomide (P = .028). Low CRBN expression affected progression-free survival (PFS; P = .017) but not overall survival (OS) in patients treated with thalidomide and had no influence on OS in the bortezomib group. In the Cox regression model, low CRBN expression was the most important prognostic parameter that influenced PFS in the thalidomide-treated patients (P = .012). Conclusion CRBN expression is of prognostic value in MM patients ineligible for ASCT treated with thalidomide as an immunomodulatory drug. With low expression indicating a possible suboptimal treatment outcome, measurement of CRBN expression might serve as additional prognostic tool in the personalized treatment approach. © 2016 Elsevier Inc.

Within a personalized treatment approach in multiple myeloma (MM), the prognostic significance of cereblon (CRBN) expression was analyzed in 92 newly diagnosed patients. In patients treated with thalidomide-based combinations, CRBN expression significantly affected the treatment response (P = .028) and progression-free survival (P = .017). With implications for the treatment outcome, measurement of CRBN expression might represent an additional prognostic tool in a personalized treatment approach. Background To personalize the treatment approach for patients with multiple myeloma (MM), molecular markers such as cereblon (CRBN) are currently the focus of investigation. The aim of the present study was to test the prognostic significance of CRBN expression in MM patients ineligible for autologous stem cell transplantation (ASCT). Patients and Methods The data from 92 previously untreated patients were analyzed. The distribution according to the International Staging System score was 26.1%, 30.4%, and 43.5% with a score of 1, 2, and 3, respectively. Thalidomide- and bortezomib-based combinations were used in 83.7% and 16.3% of the patients, respectively. Results A treatment response (complete remission, very good partial remission, partial remission) was achieved in 83.7% of the patients and correlated with high CRBN expression (P = .006), mainly in the patients treated with thalidomide (P = .028). Low CRBN expression affected progression-free survival (PFS; P = .017) but not overall survival (OS) in patients treated with thalidomide and had no influence on OS in the bortezomib group. In the Cox regression model, low CRBN expression was the most important prognostic parameter that influenced PFS in the thalidomide-treated patients (P = .012). Conclusion CRBN expression is of prognostic value in MM patients ineligible for ASCT treated with thalidomide as an immunomodulatory drug. With low expression indicating a possible suboptimal treatment outcome, measurement of CRBN expression might serve as additional prognostic tool in the personalized treatment approach. © 2016 Elsevier Inc.