scholarly journals Integrated Structure-Transcription analysis of small molecules reveals widespread noise in drug-induced transcriptional responses and a transcriptional signature for drug-induced phospholipidosis

2017 ◽  
Author(s):  
Francesco Sirci ◽  
Francesco Napolitano ◽  
Sandra Pisonero-Vaquero ◽  
Diego Carrella ◽  
Diego L. Medina ◽  
...  
Keyword(s):  
Small Molecules ◽  
Mode Of Action ◽  
Drug Repositioning ◽  
Transcriptional Response ◽  
Integrated Analysis ◽  
Transcriptional Responses ◽  
Drug Induced ◽  
Transcription Analysis ◽  
Transcriptional Signature ◽  
Chemical Structures

AbstractWe performed an integrated analysis of drug chemical structures and drug-induced transcriptional responses. We demonstrated that a network representing 3D structural similarities among 5,452 compounds can be used to automatically group together drugs with similar scaffolds and mode-of-action. We then compared the structural network to a network representing transcriptional similarities among a subset of 1,309 drugs for which transcriptional response were available in the Connectivity Map dataset. Analysis of structurally similar, but transcriptionally different, drugs sharing the same mode of action (MOA) enabled us to detect and remove weak and noisy transcriptional responses, greatly enhancing the reliability and usefulness of transcription-based approaches to drug discovery and drug repositioning. Analysis of transcriptionally similar, but structurally different drugs with unrelated MOA, led us to the identification of a “toxic” transcriptional signature indicative of lysosomal stress (lysosomotropism) and lipid accumulation (phospholipidosis) partially masking the target-specific transcriptional effects of these drugs. We further demonstrated by High Content Screening that this transcriptional signature is caused by the activation of the transcription factor TFEB, a master regulator of lysosomal biogenesis and autophagy. Our results show that chemical structures and transcriptional profiles provide complementary information and that combined analysis can lead to new insights on on- and off-target effects of small molecules.

scholarly journals The transcriptomic response of cells to a drug combination is more than the sum of the responses to the monotherapies

2019 ◽  
Author(s):  
Jennifer E. L. Diaz ◽  
Mehmet Eren Ahsen ◽  
Thomas Schaffter ◽  
Xintong Chen ◽  
Ronald B. Realubit ◽  
...  
Keyword(s):  
Time Course ◽  
Transcriptional Response ◽  
Unrelated Individual ◽  
Drug Combinations ◽  
Prediction Algorithm ◽  
Transcriptional Responses ◽  
Transcriptomic Response ◽  
Transcriptional Signature ◽  
Activation Of Transcription ◽  
Sequential Activation

AbstractOur ability to predict the effects of drug combinations is limited, in part by limited understanding of how the transcriptional response of two monotherapies results in that of their combination. We performed the first analysis of matched time course RNAseq profiling of cells treated with both single drugs and their combinations. The transcriptional signature of the synergistic combination we studied had unique gene expression not seen in either constituent monotherapy. This can be explained mechanistically by the sequential activation of transcription factors in time in the gene regulatory network. The nature of this transcriptional cascade suggests that drug synergy may ensue when the transcriptional responses elicited by two unrelated individual drugs are correlated. We used these results as the basis of a simple prediction algorithm attaining an AUROC of 0.84 in the prediction of synergistic drug combinations in an independent dataset.

scholarly journals Discovery of drug mode of action and drug repositioning from transcriptional responses

2010 ◽  
Vol 107 (33) ◽  
pp. 14621-14626 ◽  
Author(s):  
F. Iorio ◽  
R. Bosotti ◽  
E. Scacheri ◽  
V. Belcastro ◽  
P. Mithbaokar ◽  
...  
Keyword(s):  
Mode Of Action ◽  
Drug Repositioning ◽  
Transcriptional Responses

scholarly journals The transcriptomic response of cells to a drug combination is more than the sum of the responses to the monotherapies

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Jennifer EL Diaz ◽  
Mehmet Eren Ahsen ◽  
Thomas Schaffter ◽  
Xintong Chen ◽  
Ronald B Realubit ◽  
...  
Keyword(s):  
Time Course ◽  
Transcriptional Response ◽  
Unrelated Individual ◽  
Drug Combinations ◽  
Prediction Algorithm ◽  
Transcriptional Responses ◽  
Transcriptomic Response ◽  
Transcriptional Signature ◽  
Activation Of Transcription ◽  
Sequential Activation

Our ability to discover effective drug combinations is limited, in part by insufficient understanding of how the transcriptional response of two monotherapies results in that of their combination. We analyzed matched time course RNAseq profiling of cells treated with single drugs and their combinations and found that the transcriptional signature of the synergistic combination was unique relative to that of either constituent monotherapy. The sequential activation of transcription factors in time in the gene regulatory network was implicated. The nature of this transcriptional cascade suggests that drug synergy may ensue when the transcriptional responses elicited by two unrelated individual drugs are correlated. We used these results as the basis of a simple prediction algorithm attaining an AUROC of 0.77 in the prediction of synergistic drug combinations in an independent dataset.

scholarly journals Transcriptional Signature following Inhibition of Early-Stage Cell Wall Biosynthesis in Staphylococcus aureus

2009 ◽  
Vol 53 (4) ◽  
pp. 1701-1704 ◽  
Author(s):  
A. J. O'Neill ◽  
J. A. Lindsay ◽  
K. Gould ◽  
J. Hinds ◽  
I. Chopra
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Wall ◽  
Microarray Analysis ◽  
Dna Microarray ◽  
Late Stage ◽  
Mode Of Action ◽  
Early Stage ◽  
Transcriptional Response ◽  
Cell Wall Biosynthesis ◽  
Transcriptional Signature

ABSTRACT To facilitate mode of action studies on antibacterial inhibitors of early-stage cell wall biosynthesis (CWB), we determined the transcriptional response of Staphylococcus aureus to depletion/inhibition of enzymes in this pathway by DNA microarray analysis. We identified a transcriptional signature distinct from that previously observed following exposure to inhibitors of late-stage CWB.

scholarly journals BIOSIMILARS IN INFLAMMATORY BOWEL DISEASES: an important moment for Brazilian gastroenterologists

2015 ◽  
Vol 52 (1) ◽  
pp. 76-80 ◽  
Author(s):  
Fábio Vieira TEIXEIRA ◽  
Paulo Gustavo KOTZE ◽  
Aderson Omar Mourão Cintra DAMIÃO ◽  
Sender Jankiel MISZPUTEN
Keyword(s):  
Small Molecules ◽  
Inflammatory Bowel Diseases ◽  
Generic Drugs ◽  
Specific Data ◽  
Chemical Structures ◽  
Bowel Diseases ◽  
Original Product ◽  
Inflammatory Bowel ◽  
The One ◽  
Extrapolation Of Indications

ABSTRACT Biosimilars are not generic drugs. These are more complex medications than small molecules, with identical chemical structures of monoclonal antibodies that lost their patency over time. Besides identical to the original product at the end, the process of achieving its final forms differs from the one used in the reference products. These differences in the formulation process can alter final outcomes such as safety and efficacy of the drugs. Recently, a biosimilar of Infliximab was approved in some countries, even to the management of inflammatory bowel diseases. However, this decision was based on studies performed in rheumatologic conditions such as rheumatoid arthritis and ankylosing spondylitis. Extrapolation of the indications from rheumatologic conditions was done for Crohn’s disease and ulcerative colitis based on these studies. In this article, the authors explain possible different mechanisms in the pathogenesis between rheumatologic conditions and inflammatory bowel diseases, that can lead to different actions of the medications in different diseases. The authors also alert the gastroenterological community for the problem of extrapolation of indications, and explain in full details the reasons for being care with the use of biosimilars in inflammatory bowel diseases without specific data from trials performed in this scenario.

scholarly journals Copper Availability Influences the Transcriptomic Response of Candida albicans to Fluconazole Stress

2021 ◽  
Vol 11 (4) ◽  
Author(s):  
Elizabeth W Hunsaker ◽  
Chen-Hsin Albert Yu ◽  
Katherine J Franz
Keyword(s):  
Candida Albicans ◽  
Time Course ◽  
Transcriptional Response ◽  
Metal Homeostasis ◽  
Metal Availability ◽  
Drug Induced ◽  
Transcriptomic Response ◽  
Opportunistic Fungal Pathogen ◽  
Whole Transcriptome Analysis ◽  
Whole Transcriptome

Abstract The ability of pathogens to maintain homeostatic levels of essential biometals is known to be important for survival and virulence in a host, which itself regulates metal availability as part of its response to infection. Given this importance of metal homeostasis, we sought to address how the availability of copper in particular impacts the response of the opportunistic fungal pathogen Candida albicans to treatment with the antifungal drug fluconazole. The present study reports whole transcriptome analysis via time-course RNA-seq of C. albicans cells exposed to fluconazole with and without 10 µM supplemental CuSO4 added to the growth medium. The results show widespread impacts of small changes in Cu availability on the transcriptional response of C. albicans to fluconazole. Of the 2359 genes that were differentially expressed under conditions of cotreatment, 50% were found to be driven uniquely by exposure to both Cu and fluconazole. The breadth of metabolic processes that were affected by cotreatment illuminates a fundamental intersectionality between Cu metabolism and fungal response to drug stress. More generally, these results show that seemingly minor fluctuations in Cu availability are sufficient to shift cells’ transcriptional response to drug stress. Ultimately, the findings may inform the development of new strategies that capitalize on drug-induced vulnerabilities in metal homeostasis pathways.

scholarly journals Tumor hypoxia induces nuclear paraspeckle formation through HIF-2α dependent transcriptional activation of NEAT1 leading to cancer cell survival

Oncogene ◽  
2014 ◽  
Vol 34 (34) ◽  
pp. 4482-4490 ◽  
Author(s):  
H Choudhry ◽  
A Albukhari ◽  
M Morotti ◽  
S Haider ◽  
D Moralli ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cell ◽  
Transcriptional Activation ◽  
Cellular Proliferation ◽  
Hypoxia Inducible Factor ◽  
Tumor Hypoxia ◽  
Transcriptional Response ◽  
Clonogenic Survival ◽  
Breast Cancer Cell Lines ◽  
Transcriptional Responses

Abstract Activation of cellular transcriptional responses, mediated by hypoxia-inducible factor (HIF), is common in many types of cancer, and generally confers a poor prognosis. Known to induce many hundreds of protein-coding genes, HIF has also recently been shown to be a key regulator of the non-coding transcriptional response. Here, we show that NEAT1 long non-coding RNA (lncRNA) is a direct transcriptional target of HIF in many breast cancer cell lines and in solid tumors. Unlike previously described lncRNAs, NEAT1 is regulated principally by HIF-2 rather than by HIF-1. NEAT1 is a nuclear lncRNA that is an essential structural component of paraspeckles and the hypoxic induction of NEAT1 induces paraspeckle formation in a manner that is dependent upon both NEAT1 and on HIF-2. Paraspeckles are multifunction nuclear structures that sequester transcriptionally active proteins as well as RNA transcripts that have been subjected to adenosine-to-inosine (A-to-I) editing. We show that the nuclear retention of one such transcript, F11R (also known as junctional adhesion molecule 1, JAM1), in hypoxia is dependent upon the hypoxic increase in NEAT1, thereby conferring a novel mechanism of HIF-dependent gene regulation. Induction of NEAT1 in hypoxia also leads to accelerated cellular proliferation, improved clonogenic survival and reduced apoptosis, all of which are hallmarks of increased tumorigenesis. Furthermore, in patients with breast cancer, high tumor NEAT1 expression correlates with poor survival. Taken together, these results indicate a new role for HIF transcriptional pathways in the regulation of nuclear structure and that this contributes to the pro-tumorigenic hypoxia-phenotype in breast cancer.

scholarly journals Insights into the Mode of Action of Chitosan as an Antibacterial Compound

2008 ◽  
Vol 74 (12) ◽  
pp. 3764-3773 ◽  
Author(s):  
Dina Raafat ◽  
Kristine von Bargen ◽  
Albert Haas ◽  
Hans-Georg Sahl
Keyword(s):  
Antimicrobial Activity ◽  
Cell Wall ◽  
Cell Membrane ◽  
Mode Of Action ◽  
Membrane Lipids ◽  
Expression Profiles ◽  
Transcriptional Response ◽  
Response Analysis ◽  
Sequence Of Events ◽  
Wide Range

ABSTRACT Chitosan is a polysaccharide biopolymer that combines a unique set of versatile physicochemical and biological characteristics which allow for a wide range of applications. Although its antimicrobial activity is well documented, its mode of action has hitherto remained only vaguely defined. In this work we investigated the antimicrobial mode of action of chitosan using a combination of approaches, including in vitro assays, killing kinetics, cellular leakage measurements, membrane potential estimations, and electron microscopy, in addition to transcriptional response analysis. Chitosan, whose antimicrobial activity was influenced by several factors, exhibited a dose-dependent growth-inhibitory effect. A simultaneous permeabilization of the cell membrane to small cellular components, coupled to a significant membrane depolarization, was detected. A concomitant interference with cell wall biosynthesis was not observed. Chitosan treatment of Staphylococcus simulans 22 cells did not give rise to cell wall lysis; the cell membrane also remained intact. Analysis of transcriptional response data revealed that chitosan treatment leads to multiple changes in the expression profiles of Staphylococcus aureus SG511 genes involved in the regulation of stress and autolysis, as well as genes associated with energy metabolism. Finally, a possible mechanism for chitosan's activity is postulated. Although we contend that there might not be a single classical target that would explain chitosan's antimicrobial action, we speculate that binding of chitosan to teichoic acids, coupled with a potential extraction of membrane lipids (predominantly lipoteichoic acid) results in a sequence of events, ultimately leading to bacterial death.

scholarly journals The dynamic effect of regulatory genetic variation on the in vivo ER stress transcriptional response

2021 ◽  
Author(s):  
Nikki D. Russell ◽  
Clement Y. Chow
Keyword(s):  
Genetic Variation ◽  
Stress Response ◽  
Er Stress ◽  
Transcriptional Response ◽  
Mouse Strains ◽  
Transcriptional Responses ◽  
Er Stress Response ◽  
Multiple Environments ◽  
Context Specific

AbstractGenotype x Environment (GxE) interactions occur when environmental conditions drastically change the effect of a genetic variant. In order to truly understand the effect of genetic variation, we need to incorporate multiple environments into our analyses. Many variants, under steady state conditions, may be silent or even have the opposite effect under stress conditions. This study uses an in vivo mouse model to investigate how the effect of genetic variation changes with tissue type and cellular stress. Endoplasmic reticulum (ER) stress occurs when misfolded proteins accumulate in the ER. This triggers the unfolded protein response (UPR), a large transcriptional response which attempts to return the cell to homeostasis. This transcriptional response, despite being a well conserved, basic cellular process, is highly variable across different genetic backgrounds, making it an ideal system to study GxE effects. In this study, we sought to better understand how genetic variation alters expression across tissues, in the presence and absence of ER stress. The use of different mouse strains and their F1s allow us to also identify context specific cis- and trans-regulatory mechanisms underlying variable transcriptional responses. We found hundreds of genes that respond to ER stress in a tissue- and/or genotype-dependent manner. Genotype-dependent ER stress-responsive genes are enriched for processes such as protein folding, apoptosis, and protein transport, indicating that some of the variability occurs in canonical ER stress factors. The majority of regulatory mechanisms underlying these variable transcriptional responses derive from cis-regulatory variation and are unique to a given tissue or ER stress state. This study demonstrates the need for incorporating multiple environments in future studies to better elucidate the effect of any particular genetic factor in basic biological pathways, like the ER stress response.Author SummaryThe effect of genetic variation is dependent on environmental context. Here we use genetically diverse mouse strains to understand how genetic variation interacts with stress state to produce variable transcriptional profiles. In this study, we take advantage of the endoplasmic reticulum (ER) stress response which is a large transcriptional response to misfolded proteins. Using this system, we uncovered tissue- and ER stress-specific effects of genetic variation on gene expression. Genes with genotype-dependent variable expression levels in response to ER stress were enriched for canonical ER stress functions, such as protein folding and transport. These variable effects of genetic variation are driven by unique sets of regulatory variation that are only active under context-specific circumstances. The results of this study highlight the importance of including multiple environments and genetic backgrounds when studying the ER stress response and other cellular pathways.

scholarly journals Hap2-3-5-Gln3 determine transcriptional activation of GDH1 and ASN1 under repressive nitrogen conditions in the yeast Saccharomyces cerevisiae

Microbiology ◽  
2011 ◽  
Vol 157 (3) ◽  
pp. 879-889 ◽  
Author(s):  
Hugo Hernández ◽  
Cristina Aranda ◽  
Geovani López ◽  
Lina Riego ◽  
Alicia González
Keyword(s):  
Dna Binding ◽  
Transcriptional Activation ◽  
Specific Binding ◽  
Transcriptional Response ◽  
Transcriptional Regulator ◽  
Transcriptional Responses ◽  
Yeast Saccharomyces Cerevisiae ◽  
Activation Domains ◽  
Transcriptional Complex ◽  
Nitrogen Conditions

The transcriptional activation response relies on a repertoire of transcriptional activators, which decipher regulatory information through their specific binding to cognate sequences, and their capacity to selectively recruit the components that constitute a given transcriptional complex. We have addressed the possibility of achieving novel transcriptional responses by the construction of a new transcriptional regulator – the Hap2-3-5-Gln3 hybrid modulator – harbouring the HAP complex polypeptides that constitute the DNA-binding domain (Hap2-3-5) and the Gln3 activation domain, which usually act in an uncombined fashion. The results presented in this paper show that transcriptional activation of GDH1 and ASN1 under repressive nitrogen conditions is achieved through the action of the novel Hap2-3-5-Gln3 transcriptional regulator. We propose that the combination of the Hap DNA-binding and Gln3 activation domains results in a hybrid modulator that elicits a novel transcriptional response not evoked when these modulators act independently.

Sign in / Sign up

Export Citation Format

Share Document