Microtubule Organization: A Pericentriolar Material-Like Structure in Yeast Meiosis

SummaryDuring meiotic prophase in fission yeast, the nucleus undergoes dramatic oscillatory movements. A newly identified structure, the radial microtubule organizing center (rMTOC), mediates these movements and shares some of the features of the pericentriolar material in higher eukaryotes

Growth inhibition and apoptosis induced by 2 phenoxymethyl-3H-quinazolin-4-one in HL-60 leukemia cells

Aim: The aim of the study was to investigate anticancer activity of newly synthesized 2-phenoxymethyl-3H-quinazolin-4-one (PMQ). Materials and Methods: Anticancer activity of PMQ was studied towards human HL-60 leukemia cells. Antiproliferative activity of PMQ was determined by direct counting of cells using trypan blue staining technique. Apoptosis and cell cycle profile changes were analysed using internucleosomal DNA fragmentation assay and flow cytometry. Activation of caspases and changes in glutathione level were monitored using colorimetric or luminiscent methods. Results: PMQ induced concentration-dependent cytotoxicity in leukemia cells, with IC50 of 10.8 ± 0.9 µM. DNA flow cytometry analysis and DNA ladder formation assay indicated that PMQ actively induced apoptosis of cells accompanied by a block of cells in G2/M phase and a marked loss of cells in G0/G1 and S phases. Additionally, the activities of caspase-3 and caspase-9 were increased significantly and a markedly increased level of oxidized glutahione was observed. Inhibition of glutahione synthesis using buthionine sulfoximine sensitized leukemia cells to PMQ, confirming the involvement of ROS in PMQ-induced apoptosis. Conclusion: The results of this study clearly demonstrate that PMQ is a promising anticancer drug showing cytostatic and apoptotic effects toward HL-60 leukemia cells mainly through mitochondrial/caspase-9 dependent pathway.Цель: изучить антипролиферативную активность нового синтезированного 2-феноксиметил-3Н-хиназолин-4-она (PMQ). Материалы и методы: антипролиферативную активность PMQ определяли по отношению к клеткам лейкоза линии HL-60 в тесте с трипановым синим при стандартном подсчете клеток. Апоптоз и клеточный цикл оценивали с помощью проточной цитометрии и анализа фрагментации внутриядерной ДНК. Активацию каспаз и изменения уровня глутатиона определяли колориметрическими или люминисцентными методами. Результаты: PMQ индуцирует дозозависимую цитотоксичность в клетках линии HL-60 (IC50 при 10,8 ± 0,9 μM). При проведении анализа ДНК с применением проточной цитометрии и определением формирования апоптической лестницы было показано, что PMQ активно индуцирует апоптоз и блокаду клеточного цикла в G2 /M фазе митоза и выраженной потерей клеток в G0 /G1 и S фазах. Кроме того, была достоверно повышена активность каспазы-3 и -9 и выраженно увеличен уровень окисленного глутатиона. Применение бутионин сульфоксимина привело к угнетению синтеза глутатиона и повышению чувствительности клеток HL-60 к PMQ, что подтверждает факт участия РФК в PMQ-индуцированном апоптозе. Выводы: PMQ проявил себя как потенциальное противоопухолевое средство против клеток лейкоза человека HL-60 с выраженным цитостатическим и проапоптическим действием

Antiproliferative activity and apoptosis induced by 6-bromo-2-(morpholin-1-yl)-4-anilinoquinazoline on cells of leukemia lines

Quinazolines are known to be multitarget agents with broad spectrum of biological activity. Aim: To investigate anticancer activity of newly prepared 6-bromo-2-(morpholin-1-yl)-4-anilinoquinazoline (BMAQ) towards L1210, HL-60 and U-937 leukemia cells. Materials and Methods: Growth inhibition of BMAQ-treated cells was determined by cell counting using trypan blue staining technique. Apoptosis and cell cycle profile changes were analysed using internucleosomal DNA fragmentation assay, fluorescence microscopy and flow cytometry. Activity of caspase-3 was determined using colorimetric method. Results: Cell proliferation assay showed that BMAQ caused significant decrease of cell number in a dose-dependent manner. BMAQ induced cell death by apoptosis, based on results from DNA fragmentation, fluorescence microscopy and caspase-3 assays. Conclusion: Presented results clearly demonstrate that BMAQ is a promising anticancer agent with significant antiproliferative and apoptotic activities towards leukemia cells in vitro.Квиназолины известны как химиопрепараты широкого спектра действия. Цель: на моделях лейкозных клеток линий L1210, HL-60 и U-937 изучить противоопухолевую активность нового препарата 6-бромо-2-(морфолин-1-ил)-4-аналиноиназолина (BMAQ). Методы: ингибирование роста клеток под действием BMAQ изучали путем подсчета количества клеток, окрашенных трипановым синим. Апоптоз и изменения профиля клеточного цикла исследовали с помощью флуоресцентной микроскопии, электрофореза ДНК и проточной цитометрии. Активность каспазы-3 определяли колориметрическим методом. Результаты: показано, что BMAQ вызывает значительное дозозависимое уменьшение количества лейкозных клеток. При этом клетки, обработанные BMAQ, погибают путем апоптоза, что дается образованием апоптотических телец, межнуклеосомной фрагментацией ДНК и активацией каспазы-3. Выводы: представленные результаты свидетельствуют о том, что BMAQ обладает антипролиферативной и проапоптотической активностью в отношении лейкозных клеток in vitro

Growth Modulation of Human Cells in Vitro by Mild Oxidative Stress and 1,4-Dihydropyridine Derivative Antioxidants

Reactive oxygen species and lipid peroxidation products are not only cytotoxic but may also modulate signal transduction in cells. Accordingly, antioxidants may be considered as modifiers of cellular redox signaling. Therefore, the effects of two novel synthetic antioxidants, analogues of 1,4-dihydropyridine derivatives, cerebrocrast and Z41-74 were analysed in vitro on human osteosarcoma cell line HOS, the growth of which can be modulated by lipid peroxidation. The cells were pretreated with either cerebrocrast or Z41-74 and afterwards exposed to mild, copper induced lipid peroxidation or to 4-hydroxynonenal (HNE), the end product of lipid peroxidation. The results obtained have shown that both antioxidants exert growth modulating effects interfering with the lipid peroxidation. Namely, cells treated with antioxidants showed increased metabolic rate and cell growth, thereby attenuating the effects of lipid peroxidation. Such biomodulating effects of cerebrocrast and Z41-74 resembled growth modulating effects of HNE, suggesting that the antioxidants could eventually promote cellular adaptation to oxidative stress interacting with redox signaling and hydroxynonenal HNE-signal transduction pathways. This may be of particular relevance for better understanding the beneficial role of hydroxynonenal HNE in cell growth control. Therefore, cerebrocrast and Z41-74 could be convenient to study further oxidative homeostasis involving lipid peroxidation

Adjuvant Cancer Biotherapy by Viscum Album Extract Isorel: Overview of Evidence Based Medicine Findings

Within the integrative medicine one of the most frequently used adjuvant cancer biotherapies is based on aqueous mistletoe (Viscum album) extracts. Tumor growth inhibition, stimulation of host immune response and improvement of the quality of life are the positive effects of mistletoe therapy described in several preclinical and clinical studies. However, cumulative results of the evidence based medicine findings on such treatments are rarely given. Therefore, this paper evaluates the evidence based findings describing effects of the Viscum album extract Isorel in cancer therapy with respect to the type of therapy, stage and type of illness. This study presents cumulated data for 74 patients with different types and stages of cancer treated by Viscum album extract as adjuvant treatment to different conventional therapies, mostly combined surgery and radiotherapy. The biotherapy effectiveness was evaluated according to the outcome as 1) no major therapeutic improvement (15% of patients), 2) prevention of tumor recurrence (47% of patients) and 3) regression of cancer (38% of patients). Notably, there was no obvious health worsening during the follow up period at all. Thus, the results obtained for conventional anticancer therapies combined with adjuvant biotherapy based on Viscum album extract seem to be beneficial for the majority of cancer patients (85%) without serious side effects

Adjuvant Cancer Biotherapy by Viscum Album Extract Isorel: Overview of Evidence Based Medicine Findings

Within the integrative medicine one of the most frequently used adjuvant cancer biotherapies is based on aqueous mistletoe (Viscum album) extracts. Tumor growth inhibition, stimulation of host immune response and improvement of the quality of life are the positive effects of mistletoe therapy described in several preclinical and clinical studies. However, cumulative results of the evidence based medicine findings on such treatments are rarely given. Therefore, this paper evaluates the evidence based findings describing effects of the Viscum album extract Isorel in cancer therapy with respect to the type of therapy, stage and type of illness. This study presents cumulated data for 74 patients with different types and stages of cancer treated by Viscum album extract as adjuvant treatment to different conventional therapies, mostly combined surgery and radiotherapy. The biotherapy effectiveness was evaluated according to the outcome as 1) no major therapeutic improvement (15% of patients), 2) prevention of tumor recurrence (47% of patients) and 3) regression of cancer (38% of patients). Notably, there was no obvious health worsening during the follow up period at all. Thus, the results obtained for conventional anticancer therapies combined with adjuvant biotherapy based on Viscum album extract seem to be beneficial for the majority of cancer patients (85%) without serious side effects

Proteomic analysis of meiosis and characterization of novel short open reading frames in the fission yeast Schizosaccharomyces pombe.

Meiosis is the process by which haploid gametes are produced from diploid precursor cells. We used stable isotope labeling by amino acids in cell culture (SILAC) to characterize the meiotic proteome in the fission yeast Schizosaccharomyces pombe. We compared relative levels of proteins extracted from cells harvested around meiosis I with those of meiosis II, and proteins from premeiotic S phase with the interval between meiotic divisions, when S phase is absent. Our proteome datasets revealed peptides corresponding to short open reading frames (sORFs) that have been previously identified by ribosome profiling as new translated regions. We verified expression of selected sORFs by Western blotting and analyzed the phenotype of deletion mutants. Our data provide a resource for studying meiosis that may help understand differences between meiosis I and meiosis II and how S phase is suppressed between the two meiotic divisions