DeepADEMiner: a deep learning pharmacovigilance pipeline for extraction and normalization of adverse drug event mentions on Twitter

Algorithms and the Foundations of Software technolog

Polo-like kinase 1 (PLK1) inhibition suppresses cell growth and enhances radiation sensitivity in medulloblastoma cells

<p>Abstract</p> <p>Background</p> <p>Medulloblastoma is the most common malignant brain tumor in children and remains a therapeutic challenge due to its significant therapy-related morbidity. Polo-like kinase 1 (<it>PLK1</it>) is highly expressed in many cancers and regulates critical steps in mitotic progression. Recent studies suggest that targeting PLK1 with small molecule inhibitors is a promising approach to tumor therapy.</p> <p>Methods</p> <p>We examined the expression of <it>PLK1 </it>mRNA in medulloblastoma tumor samples using microarray analysis. The impact of PLK1 on cell proliferation was evaluated by depleting expression with RNA interference (RNAi) or by inhibiting function with the small molecule inhibitor BI 2536. Colony formation studies were performed to examine the impact of BI 2536 on medulloblastoma cell radiosensitivity. In addition, the impact of depleting <it>PLK1 </it>mRNA on tumor-initiating cells was evaluated using tumor sphere assays.</p> <p>Results</p> <p>Analysis of gene expression in two independent cohorts revealed that <it>PLK1 </it>mRNA is overexpressed in some, but not all, medulloblastoma patient samples when compared to normal cerebellum. Inhibition of PLK1 by RNAi significantly decreased medulloblastoma cell proliferation and clonogenic potential and increased cell apoptosis. Similarly, a low nanomolar concentration of BI 2536, a small molecule inhibitor of PLK1, potently inhibited cell growth, strongly suppressed the colony-forming ability, and increased cellular apoptosis of medulloblastoma cells. Furthermore, BI 2536 pretreatment sensitized medulloblastoma cells to ionizing radiation. Inhibition of PLK1 impaired tumor sphere formation of medulloblastoma cells and decreased the expression of SRY (sex determining region Y)-box 2 (<it>SOX2</it>) mRNA in tumor spheres indicating a possible role in targeting tumor inititiating cells.</p> <p>Conclusions</p> <p>Our data suggest that targeting PLK1 with small molecule inhibitors, in combination with radiation therapy, is a novel strategy in the treatment of medulloblastoma that warrants further investigation.</p

Metformin kills and radiosensitizes cancer cells and preferentially kills cancer stem cells

The anti-cancer effects of metformin, the most widely used drug for type 2 diabetes, alone or in combination with ionizing radiation were studied with MCF-7 human breast cancer cells and FSaII mouse fibrosarcoma cells. Clinically achievable concentrations of metformin caused significant clonogenic death in cancer cells. Importantly, metformin was preferentially cytotoxic to cancer stem cells relative to non-cancer stem cells. Metformin increased the radiosensitivity of cancer cells in vitro, and significantly enhanced the radiation-induced growth delay of FSaII tumors (s.c.) in the legs of C3H mice. Both metformin and ionizing radiation activated AMPK leading to inactivation of mTOR and suppression of its downstream effectors such as S6K1 and 4EBP1, a crucial signaling pathway for proliferation and survival of cancer cells, in vitro as well as in the in vivo tumors. Conclusion: Metformin kills and radiosensitizes cancer cells and eradicates radioresistant cancer stem cells by activating AMPK and suppressing mTOR

Metformin as an Adjunctive Therapy for Pancreatic Cancer: A Review of the Literature on Its Potential Therapeutic Use

Pancreatic ductal adenocarcinoma has the worst prognosis of any cancer. New adjuvant chemotherapies are urgently required, which are well tolerated by patients with unresectable cancers. This paper reviews the existing proof of concept data, namely laboratory, pharmacoepidemiological, experimental medicine and clinical trial evidence for investigating metformin in patients with pancreatic ductal adenocarcinoma. Laboratory evidence shows metformin inhibits mitochondrial ATP synthesis which directly and indirectly inhibits carcinogenesis. Drug–drug interactions of metformin with proton pump inhibitors and histamine H2-receptor antagonists may be of clinical relevance and pertinent to future research of metformin in pancreatic ductal adenocarcinoma. To date, most cohort studies have demonstrated a positive association with metformin on survival in pancreatic ductal adenocarcinoma, although there are many methodological limitations with such study designs. From experimental medicine studies, there are sparse data in humans. The current trials of metformin have methodological limitations. Two small randomized controlled trials (RCTs) reported null findings, but there were potential inequalities in cancer staging between groups and poor compliance with the intervention. Proof of concept data, predominantly from laboratory work, supports assessing metformin as an adjunct for pancreatic ductal adenocarcinoma in RCTs. Ideally, more experimental medicine studies are needed for proof of concept. However, many feasibility criteria need to be answered before such trials can progress

Metformin Represses Self-Renewal of the Human Breast Carcinoma Stem Cells via Inhibition of Estrogen Receptor-Mediated OCT4 Expression

Metformin, a Type II diabetic treatment drug, which inhibits transcription of gluconeogenesis genes, has recently been shown to lower the risk of some diabetes-related tumors, including breast cancer. Recently, “cancer stem cells” have been demonstrated to sustain the growth of tumors and are resistant to therapy. To test the hypothesis that metformin might be reducing the risk to breast cancers, the human breast carcinoma cell line, MCF-7, grown in 3-dimensional mammospheres which represent human breast cancer stem cell population, were treated with various known and suspected breast cancer chemicals with and without non-cytotoxic concentrations of metformin. Using OCT4 expression as a marker for the cancer stem cells, the number and size were measured in these cells. Results demonstrated that TCDD (100 nM) and bisphenol A (10 µM) increased the number and size of the mammospheres, as did estrogen (10 nM E2). By monitoring a cancer stem cell marker, OCT4, the stimulation by these chemicals was correlated with the increased expression of OCT4. On the other hand, metformin at 1 and 10 mM concentration dramatically reduced the size and number of mammospheres. Results also demonstrated the metformin reduced the expression of OCT4 in E2 & TCDD mammospheres but not in the bisphenol A mammospheres, suggesting different mechanisms of action of the bisphenol A on human breast carcinoma cells. In addition, these results support the use of 3-dimensional human breast cancer stem cells as a means to screen for potential human breast tumor promoters and breast chemopreventive and chemotherapeutic agents

Understanding the benefit of metformin use in cancer treatment

Biguanides have been developed for the treatment of hyperglycemia and type 2 diabetes. Recently, metformin, the most widely prescribed biguanide, has emerged as a potential anticancer agent. Epidemiological, preclinical and clinical evidence supports the use of metformin as a cancer therapeutic. The ability of metformin to lower circulating insulin may be particularly important for the treatment of cancers known to be associated with hyperinsulinemia, such as those of the breast and colon. Moreover, metformin may exhibit direct inhibitory effects on cancer cells by inhibiting mammalian target of rapamycin (mTOR) signaling and protein synthesis. The evidence supporting a role for metformin in cancer therapy and its potential molecular mechanisms of action are discussed

Генетическая характеристика больных муковисцидозом в Российской Федерации по данным Национального регистра (2014)

The aim of this study was to investigate genetic features of patients with cystic fibrosis (CF) according to the National Register findings in Russia. Methods. The study involved 2,131 CF patients living in 74 regions of Russia who were included in the National Register of CF patients in 2014. Results. Genetic testing was performed in 89% of patients. The total mutant allele frequency was 81.2%. One hundred and twenty two mutations were found which comprised 173 genotypes; «mild» mutations took 23%. The most common mutant allele frequencies in the descending order were as follows: F508del, 51.53%; СFTRdele2,3, 5.93%; E92K, 2.62%; 3849+10kbC&gt;T, 2.14%; 2184insA, 1.80%; W1282X, 1.80%; 2143delT, 1.69 %; N1303K, 1.43%; G542X, 1.16%; 1677delTA, 0.98%; L138ins, 0.95%; R334W, 0.85%; 394delTT, 0.85%; 3821delT, 0.42%; 2789+5G&gt;A, 0.37%; S466X, 0.37%; S1196X, 0.37%; 3272-16T&gt;A, 0.34%; W1282R, 0.29%; 3944delGT, 0.21%. Typical features of CFTR mutation distribution in Russian CF patients were lower frequency of mutations which are predominant worldwide, such as F508del, G542X, N1303K, and scarce G551D, 1717-1G&gt;A, 2183AA&gt;G mutations. On contrary, СFTRdele2,3, E92K, 2184insA, 2143delT, 1677delTA, L138ins mutations which are quite rare in Western Europe were encountered more often in Russia. «Mild» mutations were more common in Russian population of CF patients compared to European countries and have being increasing last years. Conclusion. Genetic features of Russian CF patients could be provided by Slavic, Turkic and Finno-Ugric genetic influence on Russian population.Генетическому разнообразию больных муковисцидозом (МВ) в России посвящены единичные работы на ограниченной выборке больных. Цель. Выявление особенностей генетического профиля больных МВ в России по данным Национального регистра (2014). Материалы и методы. Данные пациентов с МВ (n = 2 131) из 74 регионов России, включенные в Национальный регистр больных МВ (2014). Результаты. Генетическое обследование проведено у 89,0 % больных, суммарная аллельная частота выявленных мутаций составила 81,2 %. Выявлено 122 мутации, которые сформировали 173 различных генотипа, среди которых доля «мягких» генотипов составила 23,0 %. Аллельная частота самых распространенных мутаций представлена в порядке убывания: F508del – 51,53 %, СFTRdele2,3 – 5,93 %, E92K – 2,62 %, 3849+10kbC&gt;T – 2,14 %, 2184insA – 1,80 %, W1282X – 1,80 %, 2143delT – 1,69 %, N1303K – 1,43 %, G542X – 1,16 %, 1677delTA – 0,98 %, L138ins – 0,95 %, R334W – 0,85 %, 394delTT – 0,85 %, 3821delT – 0,42 %, 2789+5G&gt;A – 0,37 %, S466X – 0,37 %, S1196X – 0,37 %, 3272-16T&gt;A – 0,34 %, W1282R – 0,29 %, 3944delGT – 0,21 %. Выявлено, что особенностями распределения мутаций. CFTRсреди российских больных МВ являются меньшая частота доминирующих в мире мутаций, таких как F508del, G542X, N1303K, единичная встречаемость мутаций G551D, 1717-1G&gt;A, 2183AA&gt;G и наоборот – более высокая частота мутаций, являющихся относительно редкими в западноевропейских странах: СFTRdele2,3, E92K, 2184insA, 2143delT, 1677delTA, L138ins. Другой особенностью является более высокая встречаемость «мягких» мутаций в России по сравнению со странами Европы. Выявлено, что доля «мягких» мутаций в популяции больных МВ на протяжении последних лет увеличивается. Заключение. При формировании населения России особенности генетического профиля российских больных МВ определяются славянскими, тюркскими и финно-угорскими влияниями

Chemical and environmental assessment of the bottom sediments in the Irtysh River (Tyumen Region, Russian Federation)

The total concentration of Al, Co, Fe, Mn, Pb, Cu, Zn, Sr, As, Cr, Ni has been determined in the test portions of the bottom sediments (sand, loamy sand, sandy loam, silt and clay loam) in the lower reach of the Irtysh River. Atomic emission spectroscopy has been used. The established concentrations do not exceed background indicators, except for Pb and As. Their maximum values are 138 and 7.2 mg/kg, respectively. Gross concentrations of metals and metalloids are in close correlation with the content of various particle size fractions in the river sediments. Emission status of the bottom sediments has been analyzed with account of particle-size classification. As a result, multiple regression equations have been obtained. The equations reflect mathematical relationship between concentration of different elements and two regressors – the proportion of clay and silt particles in the bottom sediments of the Irtysh River. Based on these equations and determining the percentage of various particle-size fractions in soils, it is possible to predict the most probable amount of the metal concentration in the test portion. The content of oil products in bottom sediments of the river has been determined by IR spectrometry. The concentration of oil products in 24 % of test portions does not exceed the maximum permissible limit equal to 20 mg/kg. The concentration of oil products varies from 21 to 73 mg/kg in the remaining test portions of the bottom sediments. The statistically significant correlations of the gross concentrations of elements with iron, manganese, organic substance and oil products in the bottom sediments of the lower reach of the Irtysh River have been revealed. The weak statistically significant pH correlations with indicators of the particle-size classification of bottom sediments have been determine