Combination of ERK2 and STAT3 Inhibitors Promotes Anticancer Effects on Acute Lymphoblastic Leukemia Cells.

BACKGROUND/AIM: Deregulated activation of signaling through the RAS/RAF/mitogen-activated protein kinase/extracellular signal-regulated kinase (RAS/RAF/MEK/ERK) and signal transducer and activator of transcription (STAT) pathways is involved in numerous hematological malignancies, making it an attractive therapeutic target. This study aimed to assess the effect of the combination of ERK2 inhibitor VX-11e and STAT3 inhibitor STA-21 on acute lymphoblastic leukemia cell lines REH and MOLT-4. MATERIALS AND METHODS: REH and MOLT-4 cell lines were cultured with each drug alone and in combination. Cell viability, ERK activity, cell cycle distribution, apoptosis and oxidative stress induction were assessed by flow cytometry. Protein levels of STAT3, phospho-STAT3, protein tyrosine phosphatase 4A3 (PTP4A3), survivin, p53 and p21 were determined by western blotting. RESULTS: VX-11e in combination with STA-21 significantly inhibited cell viability, induced G0/G1 cell-cycle arrest, enhanced production of reactive oxygen species, and induced apoptosis. These effects were associated with an increased level of p21 protein in REH cells and with reduced levels of phopho-STAT3, survivin and PTP4A3 proteins in MOLT-4 cells. CONCLUSION: Our findings provide a rationale for combined inhibition of RAS/RAF/MEK/ERK and STAT3 pathways in order to enhance anticancer effects against acute lymphoblastic leukemia cells.

Targeting the MAPK/ERK and PI3K/AKT Signaling Pathways Affects NRF2, Trx and GSH Antioxidant Systems in Leukemia Cells.

The mitogen-activated protein kinase (MAPK)/extracellular signal kinase (ERK) and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signal transduction pathways have been implicated in the pathogenesis of leukemia. The aim of this study was to investigate the effect of the combination of ERK1/2 inhibitor AZD0364 and PI3K inhibitor ZSTK474 on acute lymphoblastic leukemia (ALL) REH, MOLT-4, acute myeloid leukemia (AML) MOLM-14, and chronic myeloid leukemia (CML) K562 cell lines. To evaluate the interactions of the drugs, cells were treated for 48 h with AZD0364 or ZSTK474 alone and in combination at fixed ratios. The combinatorial effects of both inhibitors were synergistic over a wide range of concentrations in REH, MOLT-4, and MOLM-14 cell lines. However, in K562 cells, the effects were found to be antagonistic. Furthermore, AZD0364 and ZSTK474 significantly decreased both ERK1/2 and AKT activation in REH, MOLT-4, and MOLM-14 cells. The results showed that incubation with both AZD0364 and ZSTK474 inhibited cell viability, increased reactive oxygen species (ROS) production, and induced apoptosis in leukemia cells. We observed that combined treatment with AZD0364 and ZSTK474 affected nuclear factor-κB (NF-κB) and antioxidant protein levels: NF-E2-related factor 2 (NRF2), heme oxygenase-1 (HO-1), thioredoxin (Trx), thioredoxin reductase (TrxR), and the reduced glutathione/oxidized glutathione (GSH/GSSG) ratio. These effects were accompanied with decreased antiapoptotic survivin protein level. However, distinct cell line dependent effects were observed. In conclusion, the combination of AZD0364 and ZSTK474 can exert a synergistic anticancer effect in ALL and AML cells, which is associated with the induction of oxidative stress and the involvement of cellular antioxidant defense mechanisms.

Combination of ERK2 inhibitor VX-11e and voreloxin synergistically enhances anti-proliferative and pro-apoptotic effects in leukemia cells.

ERK1/2 inhibitors are new promising anticancer drugs. The aim of this study was to investigate the effect of the combination of ERK2 inhibitor VX-11e and voreloxin on MOLM-14, K562, REH and MOLT-4 leukemia cell lines. We found that VX-11e alone and in combination with voreloxin significantly decreased ERK activation in all cell lines tested. To evaluate the interactions of the drugs, cells were treated for 24 h with VX-11e or voreloxin alone and in combination at fixed ratios based on IC50 values. The combinatorial effects of both drugs were synergistic over a wide range of concentrations in MOLM-14, REH and MOLT-4 cell lines. In K562 cells, three effects were found to be additive, one antagonistic and only one synergistic. The results showed that incubation with both VX-11e and voreloxin inhibited the growth of leukemia cells, affected cell cycle and induced apoptosis. Furthermore, the molecular mechanism of these effects might be attributed to an increased expression of p21 and a decreased expression of survivin and NF-κB in all cell lines tested except from K562 cells. In conclusion, combination of VX-11e and voreloxin can exert a synergistic anticancer effect in leukemia cells.

TAK-733, a Selective MEK Inhibitor, Enhances Voreloxin-induced Apoptosis in Myeloid Leukemia Cells.

BACKGROUND/AIM: MEK inhibitors are new promising anticancer drugs. The aim of this study was to investigate the effect of the combination treatment of voreloxin with the MEK inhibitor TAK-733 on HL60 myeloid leukemia cells. MATERIALS AND METHODS: MAPK activity, cell viability, apoptosis, oxidative stress induction and AIF (apoptosis-inducing factor) distribution were assessed in HL60 cells cultured with each drug alone or with both drugs. RESULTS: TAK-733 alone at 5 µM significantly reduced MAPK activity and did not influence viability and apoptosis in HL60 cells. Voreloxin at concentration of 0.03-0.48 µM reduced cell viability and increased apoptosis rate. Incubation with both drugs caused further inhibition of cell viability and increased apoptosis associated with generation of reactive oxygen species (ROS) and nuclear translocation of AIF. CONCLUSION: Combination of TAK-733 and voreloxin can exert a synergistic anticancer effect in myeloid leukemia cells.

Results of open heart surgery in Jehovah's Witness patients. Single centre experience.

AIM: Evaluation the results in patients from the religious community of Jehovah's Witness (JW) undergoing open heart surgery at our institution. MATERIAL AND METHODS: Between September 2011 and March 2015, 21 patients with a religious background of the JW church underwent open heart surgery at our institution performed by the same surgical team. Mean age was 68.43 ±8.93 years. There were 13 (61.9%) female patients. Recombinant human erythropoietin was administered to every patient with a hemoglobin value < 12.0 g/dl. Nine patients undergoing isolated coronary artery revascularization were operated on without cardiopulmonary bypass. Seven patients underwent combined surgery and 5 patients underwent aortic valve replacement via ministernotomy. The mean follow-up time was 16.45 ±11.09 months (range: 1.67-44.3 months). RESULTS: Mean baseline hematocrit serum level was 40.15 ±3.34% (range: 34.5-46.1%). Perioperatively the hematocrit serum levels decreased to the mean level of 29.89 ±4.31% (range: 21.4-36.3%). The mean hematocrit value at discharge was 30.85 ±3.59% (range: 23.5-38.4%). One death was observed in the perioperative period. Five (24%) patients suffered from sternum wound infection requiring vacuum-assisted therapy. During the follow-up period 1 patient died due to a non-cardiac related cause. CONCLUSIONS: After careful preoperative preparation the results of open heart surgery in JW were very good, including combined procedures. The decrease of hematocrit serum levels significantly characterizing the postoperative period was highly acceptable in this series. Nevertheless, the number of sternum wound infections was a limiting factor for prompt postoperative recovery.

Emergency HeartWare Ventricular Assist Device (HVAD) exchange due to pump thrombosis using minimally invasive technique.

Left ventricular assist device (LVAD) thrombosis remains a dreadful complication of mechanical circulatory support, with an incidence of 8-12% depending on the pump type and patient's comorbidities. Fibrinolysis may be considered early in pump thrombosis, but when contraindicated a pump exchange remains the only alternative. This short report documents an emergency LVAD exchange in a 55-year-old man who underwent LVAD (HeartWare Inc) implantation in 2013 as a bridge to transplantation. Four months after the initial surgery, he suffered from a hemorrhagic stroke despite properly managed anticoagulation. On February 17th, 2017 he was re-admitted with LVAD pump thrombosis. As fibrinolysis was contraindicated, an emergency pump exchange was performed via a limited thoracic incision in order to minimize surgical trauma, reduce intraoperative complications and facilitate immediate post-operative recovery. This report documents the very first LVAD pump exchange as well as the first one performed via a minimally invasive approach in Poland.

Distribution of selected elements in calcific human aortic valves studied by microscopy combined with SR-µXRF: influence of lipids on progression of calcification.

Calcified heart valves display a significant imbalance in tissue content of trace and essential elements. The valvular calcification is an age-related process and there are data suggesting involvement of lipids. We studied elemental composition and lipid distribution in three distinct regions of calcified human aortic valves, representing successive stages of the calcific degeneration: normal, thickened (early lesion) and calcified (late lesion), using SR-µXRF (Synchrotron Radiation Micro X-Ray Fluorescence) for elemental composition and Oil Red O (ORO) staining for demonstration of lipids. Two-dimensional SR-µXRF maps and precise point spectra were compared with histological stainings on consecutive valve sections to prove topographical localization and colocalization of the examined elements and lipids. In calcified valve areas, accumulation of calcium and phosphorus was accompanied by enhanced concentrations of strontium and zinc. Calcifications preferentially developed in lipid-rich areas of the valves. Calcium concentration ratio between lipid-rich and lipid-free areas was not age-dependent in early lesions, but showed a significant increase with age in late lesions, indicating age-dependent intensification of lipid involvement in calcification process. The results suggest that mechanisms of calcification change with progression of valve degeneration and with age.

Comparative analysis of the quality of life for patients prior to and after heart transplantation.

BACKGROUND: The aim of this study was to assess the quality of life of patients before and after heart transplantation (HTX). MATERIAL AND METHODS: We included 63 patients after a heart transplant under the care of the Transplantation Clinic. The authors' questionnaire was used, which consisted of 2 parts: questions concerning the life of patients before and after a heart transplant. The significance level was p<0.05. RESULTS: In the group before the heart transplant, average quality of life (on a 10-point scale) was 3.16 ± 1.47 and in the group after the heart transplant this factor increased to 7.60 ± 1.21 (p<0.00001). Our study shows that after the heart transplant people consider their physical health to be better. In the group before the heart transplant, the average assessment of physical health on a scale from 1 to 5 was 2.079 ± 0.79 and after the heart transplant it was 4.10 ± 0.39 (p<0.0001). No statistically significant correlations were indicated between the quality of life after the heart transplant and the quality of life before the transplant, age, sex, and time elapsed after the heart transplant. There was a positive correlation between the assessment of quality of life and that of physical (r=0.53; p<0.05) and mental health (r=0.45; p<0.05). CONCLUSIONS: The study shows that the quality of life of patients after the heart transplant was significantly improved in all spheres of life under analysis: physical, mental, social, and family. The results of the study indicate that patients associated the quality of life with their physical and mental health status.

Combinatorial effects of PARP inhibitor PJ34 and histone deacetylase inhibitor vorinostat on leukemia cell lines.

BACKGROUND: Poly (ADP-ribose) polymerase (PARP) inhibitors and histone deacetylase (HDAC) inhibitors are new promising anticancer drugs. The aim of the present study was to investigate the effect of combination treatment with PARP inhibitor PJ34 and HDAC inhibitor vorinostat on human leukemia cell lines. MATERIALS AND METHODS: Proliferation, apoptosis, mitochondrial membrane potential (ψm) and cell cycle were assessed in HL60, MOLT4, U937 and K562 cells cultured with each drug alone and with both drugs. RESULTS: PJ34 alone at 0.2-0.4 µM did not influence the examined parameters. Vorinostat alone at 1.0-2.5 µM reduced proliferation, increased apoptosis rate, lowered ψm and increased the percentage of sub-G1 cells in all cell lines. Incubation with both drugs caused further inhibition of proliferation and increase in apoptosis associated with a decrease in ψm and sub-G1 arrest in HL60, MOLT4 and K562 cells, but not in U937 cells. CONCLUSION: Combination of PARP and HDAC inhibitors can exert a synergistic effect on inhibition of proliferation and increase apoptosis of leukemia cells.

Effect of histone deacetylase inhibitors trichostatin A and valproic acid on etoposide-induced apoptosis in leukemia cells.

BACKGROUND: Histone deacetylase inhibitors (HDACi) have been extensively studied as potential candidates for treatment of various malignancies, including leukemia, since they not only induce growth inhibition, cell cycle arrest and apoptosis of cancer cells, but can also increase the sensitivity of cancer cells to chemotherapeutic drugs. The aim of this study was to investigate the effect of two HDACi, trichostatin A (TSA) and valproic acid (VPA), on etoposide-induced apoptosis in human leukemia cell lines. MATERIALS AND METHODS: Viability, apoptosis rate, caspase activity, mitochondrial membrane potential and expression of BCL2 mRNA were assessed in HL60 and U937 cell lines treated with 250 nM TSA or 1.25 mM VPA alone or followed by 5 µM etoposide. RESULTS: Preincubation of HL60 cells with TSA or VPA significantly potentiated etoposide-induced cytotoxicity and apoptosis, which was associated with activation of caspases and loss of mitochondrial membrane potential. Similar effects were not observed in U937 cells. Expression of BCL2 mRNA was strongly down-regulated after treatment of cells with HDACi alone but did not show additive effect with etoposide. CONCLUSION: Combination of HDACi with etoposide can have a synergistic effect on increased apoptosis in leukemia cells but this effect depends on the cancer cell type and other factors such as the concentration of drugs and the administration schedule.

[Acute aortic dissection type A with concomitant myocardial infarction]. / Ostre rozwarstwienie aorty wstepujacej ze wspólistniejacym rozleglym zawalem serca - trudny problem kliniczny i diagnostyczny.

The authors describe a patient with acute aortic dissection type A complicated by left main coronary artery occlusion and acute myocardial infarction. The patient underwent urgent surgery, however, died 4 hours after operation.