Dagmara Baczyńska

Low expression of microRNA-204 (miR-204) is associated with poor clinical outcome of acute myeloid leukemia (AML) patients

BackgroundAcute myeloid leukemia (AML) is a heterogeneous neoplasm of the bone marrow with poor prognosis. In clinical practice new prognostic factors are still needed. MicroRNAs (miRs), small endogenous noncoding RNAs, play an essential role in the development and progression of acute leukemia. The aim of the study was to evaluate miR-204 expression in patients with AML at diagnosis and after induction chemotherapy, in comparison to healthy controls. We also investigated, if miR-204 expression correlates with clinical features of AML patients.MethodsmiR-204 expression has been analyzed using RT-PCR in 95 bone marrow specimens from newly diagnosed AML patients in comparison to 20 healthy subject.ResultsWe showed down-regulated miR-204 expression in AML patients, which was associated with shorter patients’ survival. Higher expression of miR-204 in patients after induction therapy was correlated with complete remission achieving.ConclusionsWe showed low miR-204 expression in AML and found it to be an independent prognostic factor in this patient population.

Expression of microRNA-331 can be used as a predictor for response to therapy and survival in acute myeloid leukemia patients

AIM Aberrant expression of microRNAs (miRs) has been proved to have a role in acute myeloid leukemias (AML), but there is no information on miR-331 in AML. MATERIALS & METHODS miR-331 expression has been analyzed using reverse-transcription polymerase chain reaction (RT-PCR) in 95 bone marrow specimens from newly diagnosed AML patients in comparison with 20 healthy subjects. RESULTS miR-331 was upregulated in AML patients and its expression seemed to influence remission achieving and death risk. The time of remission duration in patients with complete remission was longer in subjects with miR-331 downregulation after induction chemotherapy. CONCLUSION we showed for the first time that miR-331 higher expression appears to be correlated with worse response to therapy and shorter survival of AML patients.

Combined autologous bone marrow mononuclear cell and gene therapy as the last resort for patients with critical limb ischemia.

Introduction Our study was designed to investigate the safety and efficacy of combined autologous bone marrow mononuclear cell (MNC) and gene therapy in comparison to conventional drug therapy in patients with critical limb ischemia (CLI). Material and methods Thirty-two patients with CLI persisting for 12–48 months (average time 27.5 months) were randomized into 2 groups, each group consisting of 16 patients. In the first group, administration of autologous bone marrow MNC and vascular endothelial growth factor (VEGF) plasmid was performed. The patients from the second group were treated pharmacologically with pentoxifylline. Ankle-brachial index (ABI) was measured and angiography was performed before and finally 3 months after treatment. The pain was evaluated using the Visual Analog Scale (VAS) before and after 3 months. Results Ankle-brachial index improved significantly from 0.29 ±0.21 to 0.52 ±0.23 (p < 0.001) in 12 patients (75.0%) 3 months after the experimental therapy in group 1. In this group angiography showed the development of collateral vessels. Ischemic ulcers healed completely in 11 patients (68.75%). In group 2 the ABI did not improve in any patient; moreover the complete healing of skin ulcers was not found in any of the patients of this group. Amputation was performed in 4 (25.0%) patients in group 1, and in 8 patients (50%) from group 2. Conclusions These data after 3-month follow-up indicate that intramuscular injection of MNC combined with gene therapy in patients with chronic CLI is safe, and a more feasible and effective method of treatment than the conventional therapy. However, both therapies are limited by the degree of microcirculation damage.

Clinical response to azacitidine therapy depends on microRNA-29c (miR-29c) expression in older acute myeloid leukemia (AML) patients

Acute myeloid leukemia (AML) is a heterogeneous disease with different clinical course and prognosis. microRNA-29 (miR-29) family of non-coding small RNAs can play an important role in pathogenesis of AML, but also can influence response to therapy. The purpose of the study was to evaluate miR-29c expression in AML patients in relationship to clinical parameters and response to chemotherapy, including azacitidine. Materials and Methods miR-29c expression has been analyzed using RT-PCR in 95 bone marrow specimens from newly diagnosed AML patients in comparison to 20 healthy subject. Results We showed up-regulated miR-29c expression in AML patients which was linked also to higher risk of disease relapse after achieving complete remission. In subset of elderly AML patients treated with azacitidine, low miR-29c expression at diagnosis correlated with good response to therapy. Conclusions miR-29c is of prognostic value and influences response to azacitidine treatment in older AML patients.

Expression of microRNA‑181 determines response to treatment with azacitidine and predicts survival in elderly patients with acute myeloid leukaemia

MicroRNAs (miRs) are small non-coding RNAs that play important roles in cell differentiation and survival. Abnormal expression of miRs has been demonstrated in numerous types of cancer, including acute myeloid leukaemia (AML). The aim of the present study was to evaluate miR-181 expression at diagnosis and following the completion of chemotherapy in AML patients, with regard to clinical response and outcome, particularly in patients treated with azacitidine. miR-181 expression was analysed using reverse transcription-quantitative polymerase chain reaction in 95 bone marrow specimens from newly diagnosed AML patients and in 20 healthy subjects for comparison. The results revealed upregulated miR-181 expression in the total cohort of AML patients, which was correlated with longer survival. However, in a subset of older AML patients treated with azacitidine, low miR-181 expression at diagnosis was a predictor for complete remission and prolonged survival. The findings indicated that miR-181 has an important role in AML and determines response to azacitidine treatment in older AML patients.

Presence of Periodontopathic Bacteria DNA in Atheromatous Plaques from Coronary and Carotid Arteries

Objectives. Interest in periodontitis as a potential risk factor for atherosclerosis and its complications resulted from the fact that the global prevalence of periodontal diseases is significant and periodontitis may induce a chronic inflammatory response. Many studies have analyzed the potential impact of the Porphyromonas gingivalis, major pathogen of periodontitis, on general health. The purpose of this study was to find the presence of the Porphyromonas gingivalis DNA in the atherosclerotic plaques of coronary and carotid arteries and in the periodontal pockets in patients with chronic periodontitis, who underwent surgery because of vascular diseases. Methods and Results. The study population consisted of 91 patients with coronary artery disease or scheduled for carotid endarterectomy. The presence of Porphyromonas gingivalis DNA in atheromatous plaques and in subgingival samples was determined by PCR. Bacterial DNA was found in 21 of 91 (23%) samples taken from vessels and in 47 of 63 (74.6%) samples from periodontal pockets. Conclusions. Porphyromonas gingivalis DNA is frequently found in atheromatous plaques of patients with periodontitis. That is why more research should be conducted to prove if this periopathogen may have an impact on endothelium of patients at risk of atherosclerosis.

Stability of Tandemly Repetitive Subelement PCR Patterns in Trichophyton rubrum over Serial Passaging and with Respect to Drug Pressure

Trichophyton rubrum is the most significant agent of dermatomycoses worldwide, primarily causing tinea pedis and tinea unguium. PCR analysis of tandemly repetitive subelements (TRS) within the rDNA nontranscribed spacer region is a major tool for molecular typing of T. rubrum. The aim of this study was to investigate the stability of TRS PCR patterns by analyzing isogenic strains of T. rubrum. Twenty-seven groups of isogenic T. rubrum strains were examined, each composed of an original clinical isolate and its 3 subcultures, maintained on a drug-free medium, a medium containing fluconazole and itraconazole. TRS typing was performed for the original strains and their subcultures grown after 12 passages, at 4-week intervals, on respective media. To add more objectivity to the results, TRS typing for each of the isogenic strain was performed three times, using DNA isolated from three different colonies. Among 27 groups of isogenic strains, all but one were exclusively composed of strains with identical TRS-1 and TRS-2 PCR patterns. In one group, 3 isolates from the last, twelfth passage had identical TRS-1 PCR profiles (type 1), yet different TRS-2 PCR profiles, as compared with the original strain (type I vs. type II). The mechanism underlying the genotype switch was a deletion of a single repeat unit in the TRS-2 locus, as evidenced by sequence analysis. In the interpretation of TRS typing results, microevolutionary events need to be taken into account, urging drawing epidemiological conclusions with caution and in conjunction with other genotyping data and traditional contact tracing information.

Role of vascular endothelial growth factor in inducing production of angiopoetin-1 - in vivo study in Fisher rats

The aim of the study was to investigate how an intramuscular injection of plasmids with genes coding various pro-angiogenic factors: angiopoetin-1 (ANGPT1), vascular endothelial growth factor (VEGF165) and hepatic growth factor (HGF), influences the production of ANGPT1. 40 Healthy Fisher rats received i.m. injections containing plasmids encoding pro-angiogenic genes in thigh muscles. They were divided into four equal groups. The first group received the plANGPT1 plasmid and the second group- the pIRES/ANGPT1/VEGF165 bicistronic plasmid. The pIRES/VEGF165/HGF bicistronic plasmid was administered to the third group and an empty plasmid (control group) to the fourth group. The animals were euthanized after 12 weeks. In each group, the number of vessels stained with the anti-ANGPT1 antibody was assessed under an optical microscope. The anti-ANGPT1 antibodies stained the vessels in all the groups. There were on average 14.1 ±2.3 vessels in the the plANGPT1 group, 32.5 ±10.5 in the pl/RESANGPT1/VEGF group and 30.8 ±13.3 in the plRES/HGV/VEGF group. There were on average 7.3 ±2.3 stained vessels (p < 0.0001) in the control group . The VEGF plays a role in the induction of the production of ANGPT1. The administration of plasmids only encoding ANGPT1 does not induce its production.

Antiproliferative and antioxidant activity of xanthohumol acyl derivatives

A series of mono- and diacyl- xanthohumol (1) derivatives was synthesized with yields of 10–30%. All the compounds were tested against the antiproliferative activity of human cancer cell line of colon adenocarcinoma (HT-29) using SRB assay. The most active (IC50 values < 12 μM) were three compounds: 4-O-acetylxanthohumol (2) (IC50 = 11.84 μM), 4,4′-Di-O-acetylxanthohumol (3) (IC50 = 11.75 μM) and 4-Odecanoylxanthohumol (4) (IC50 = 10.04 μM). For the starting compound xanthohumol (1) IC50 = 9.74 μM. The antioxidant activity was determined by the method of 2.2-diphenyl-1-picrylhydrazyl radical and 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid and expressed as μM of Trolox equivalent antioxidant capacity per gram. Only one compound 4-O-acetylxanthohumol (2) (15 μM Trolox equivalent antioxidant capacity for 2,2-diphenyl-1-picrylhydrazyl radical and 160 μM Trolox equivalent antioxidant capacity for 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid methods) showed a lower antioxidant activity compared to xanthohumol (1) (38 μM Trolox equivalent antioxidant capacity for 2,2-diphenyl-1-picrylhydrazyl radical and 19 μM Trolox equivalent antioxidant capacity for 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid methods). Other tested compounds showed comparable or higher antioxidant activity as xanthohumol (1).

The Formation of Blood Vessel After the Administration of the Plasmid Encoding Ang-1 Gene in Fischer Rats.

BACKGROUND Chronic limb ischemia is a serious clinical problem. Patients who do not qualify for standard treatment may benefit from novel gene therapies. OBJECTIVES This study evaluated angiogenesis following intramuscular injections of angiogenic plasmid Ang-1 in Fisher rats. MATERIAL AND METHODS Twenty rats had plasmids injected intramuscularly in their hind limbs. The study group consisted of 10 animals which received the Ang-1 plasmid, while the control group consisted of 10 rats that received an empty plasmid. All the animals were euthanized after 12 weeks and tissue samples from the hind limb thigh muscles and internal organs were harvested for histological and immunohistochemical examinations. To assess the angiogenesis the number of vessels in the hind limb muscles visualized by the SMA and FVIII markers was counted for each animal in five separate microscopic fields. RESULTS There were no pathological lesions or any signs of neoplastic angiogenesis in any of the 20 rats. The number of vessels visualized by the FVIII marker in the study group was two times higher than in the control group (median: 12, range: 7-25 vs. median: 6, range: 2-15; p < 0.0001). The median estimated that the number of vessels visualized by the SMA marker is 63% higher in the study group compared to the control group (median: 6.5, range: 1-12 vs. median: 4, range: 0-10; p = 0.0008). CONCLUSIONS Intramuscular injections of Ang-1 plasmids induced angiogenesis in the rat hind limb muscles.