Magic power of phosphoinositide 3-kinase inhibitors

2017 ◽  
Vol 5 (1) ◽  
Author(s):  
Xiangdong Wang

Phosphoinositide 3-kinases (PI3K) play critical roles in the maintenance of cell biological functions and are suggested as a therapeutic target for drug discovery and development. PI3K inhibitors has the magic power to prevent the development of pathological changes and cure the diseases, while such magic powers can be faded by the large profile of their toxicity and side-effects. A number of strategies can prevent, reduce, or decline PI3K inhibitor-associated toxicities, e.g. to make the inhibitors targeting the core molecules more precisely, select the optimal approach of drug delivery, bind the “recognizing” pullets with PI3K inhibitors to target-specific cells, or gene editing. We spotlight that PI3K definitely is an important therapeutic targets for cancer, inflammation, or organ dysfunction and injury, while to catch and hold such magic power of PI3K inhibitors is still the challenge to be faced and solved.

Blood ◽  
2009 ◽  
Vol 113 (22) ◽  
pp. 5549-5557 ◽  
Author(s):  
Matthias Niedermeier ◽  
Bryan T. Hennessy ◽  
Zachary A. Knight ◽  
Marina Henneberg ◽  
Jianhua Hu ◽  
...  

Phosphoinositide 3-kinases (PI3Ks) are among the most frequently activated signaling pathways in cancer. In chronic lymphocytic leukemia (CLL), signals from the microenvironment are critical for expansion of the malignant B cells, and cause constitutive activation of PI3Ks. CXCR4 is a key receptor for CLL cell migration and adhesion to marrow stromal cells (MSCs). Because of the importance of CXCR4 and PI3Ks for CLL-microenvironment cross-talk, we investigated the activity of novel, isoform-selective PI3K inhibitors that target different isoforms of the p110-kDa subunit. Inhibition with p110α inhibitors (PIK-90 and PI-103) resulted in a significant reduction of chemotaxis and actin polymerization to CXCL12 and reduced migration beneath MSC (pseudoemperipolesis). Western blot and reverse phase protein array analyses consistently demonstrated that PIK-90 and PI-103 inhibited phosphorylation of Akt and S6, whereas p110δ or p110β/p110δ inhibitors were less effective. In suspension and MSC cocultures, PI-103 and PIK-90 were potent inducers of CLL cell apoptosis. Moreover, these p110α inhibitors enhanced the cytotoxicity of fludarabine and reversed the protective effect of MSC on fludarabine-induced apoptosis. Collectively, our data demonstrate that p110α inhibitors antagonize stromal cell-derived migration, survival, and drug-resistance signals and therefore provide a rational to explore the therapeutic activity of these promising agents in CLL.


2021 ◽  
Vol 22 (7) ◽  
pp. 3567
Author(s):  
Viviana Mannella ◽  
Kira Boehm ◽  
Suheyla Celik ◽  
Tasnim Ali ◽  
Amnah N. Mirza ◽  
...  

Cutaneous squamous cell carcinomas (cSCCs) account for about 20% of keratinocyte carcinomas, the most common cancer in the UK. Therapeutic options for cSCC patients who develop metastasis are limited and a better understanding of the biochemical pathways involved in cSCC development/progression is crucial to identify novel therapeutic targets. Evidence indicates that the phosphoinositide 3-kinases (PI3Ks)/Akt pathway plays an important role, in particular in advanced cSCC. Questions remain of whether all four PI3K isoforms able to activate Akt are involved and whether selective inhibition of specific isoform(s) might represent a more targeted strategy. Here we determined the sensitivity of four patient-derived cSCC cell lines to isoform-specific PI3K inhibitors to start investigating their potential therapeutic value in cSCC. Parallel experiments were performed in immortalized keratinocyte cell lines. We observed that pan PI3Ks inhibition reduced the growth/viability of all tested cell lines, confirming the crucial role of this pathway. Selective inhibition of the PI3K isoform p110α reduced growth/viability of keratinocytes and of two cSCC cell lines while affecting the other two only slightly. Importantly, p110α inhibition reduced Akt phosphorylation in all cSCC cell lines. These data indicate that growth and viability of the investigated cSCC cells display differential sensitivity to isoform-specific PI3K inhibitors.


2020 ◽  
Vol 20 (12) ◽  
pp. 1074-1092 ◽  
Author(s):  
Rammohan R.Y. Bheemanaboina

Phosphoinositide 3-kinases (PI3Ks) are a family of ubiquitously distributed lipid kinases that control a wide variety of intracellular signaling pathways. Over the years, PI3K has emerged as an attractive target for the development of novel pharmaceuticals to treat cancer and various other diseases. In the last five years, four of the PI3K inhibitors viz. Idelalisib, Copanlisib, Duvelisib, and Alpelisib were approved by the FDA for the treatment of different types of cancer and several other PI3K inhibitors are currently under active clinical development. So far clinical candidates are non-selective kinase inhibitors with various off-target liabilities due to cross-reactivities. Hence, there is a need for the discovery of isoform-selective inhibitors with improved efficacy and fewer side-effects. The development of isoform-selective inhibitors is essential to reveal the unique functions of each isoform and its corresponding therapeutic potential. Although the clinical effect and relative benefit of pan and isoformselective inhibition will ultimately be determined, with the development of drug resistance and the demand for next-generation inhibitors, it will continue to be of great significance to understand the potential mechanism of isoform-selectivity. Because of the important role of type I PI3K family members in various pathophysiological processes, isoform-selective PI3K inhibitors may ultimately have considerable efficacy in a wide range of human diseases. This review summarizes the progress of isoformselective PI3K inhibitors in preclinical and early clinical studies for anticancer and other various diseases.


2021 ◽  
Vol 9 (7) ◽  
pp. e002662
Author(s):  
Hongyan Wu ◽  
Xinyi Tang ◽  
Hyo Jin Kim ◽  
Shahrzad Jalali ◽  
Joshua C Pritchett ◽  
...  

BackgroundCD8+ T-lymphocyte subsets defined by killer lectin-like receptor G1 (KLRG1) and CD127 expression have been reported to have an important role in infection, but their role in the setting of lymphoid malignancies, specifically follicular lymphoma (FL), has not been studied.MethodsTo characterize the phenotype of KLRG1/CD127-defined CD8+ subsets, surface and intracellular markers were measured by flow cytometry and Cytometry by time of flight (CyTOF), and the transcriptional profile of these cells was determined by CITE-Seq (Cellular Indexing of Transcriptomes and Epitopes by Sequencing). The functional capacity of each subset was determined, as was their impact on overall survival (OS) and event-free survival (EFS) of patients with FL.ResultsWe found that intratumoral CD8+ cells in FL are skewed toward effector cell subsets, particularly KLRG+CD127- and KLRG1-CD127- cells over memory cell subsets, such as KLRG1-CD127+ and KLRG1+CD127+ cells. While effector subsets exhibited increased capacity to produce cytokines/granules when compared with memory subsets, their proliferative capacity and viability were found to be substantially inferior. Clinically, a skewed distribution of intratumoral CD8+ T cells favoring effector subtypes was associated with an inferior outcome in patients with FL. Increased numbers of CD127+KLRG1- and CD127+KLRG1+ were significantly associated with a favorable OS and EFS, while CD127-KLRG1- correlated with a poor EFS and OS in patients with FL. Furthermore, we demonstrated that interleukin (IL)-15 promotes CD127-KLRG1+ cell development in the presence of dendritic cells via a phosphoinositide 3-kinase (PI3K)-dependent mechanism, and treatment of CD8+ T cells with a PI3K inhibitor downregulated the transcription factors responsible for CD127-KLRG1+ differentiation.ConclusionsTaken together, these results reveal not only a biological and prognostic role for KLRG1/CD127-defined CD8+ subsets in FL but also a potential role for PI3K inhibitors to manipulate the differentiation of CD8+ T cells, thereby promoting a more effective antitumor immune response.


2021 ◽  
Author(s):  
Mo Chen ◽  
Suyong Choi ◽  
Tianmu Wen ◽  
Changliang Chen ◽  
Narendra Thapa ◽  
...  

The tumor suppressor p53 and the phosphoinositide 3-kinase (PI3K)-Akt pathway have fundamental roles in regulating cell growth, apoptosis and are frequently mutated in cancer. Here, we show that genotoxic stress induces nuclear Akt activation by a p53-dependent mechanism that is independent from the canonical membrane-localized PI3K-Akt pathway. Upon genotoxic stress a nuclear p53-PI3,4,5P3 complex is generated in regions devoid of membranes by a nuclear PI3K, and this complex recruits all the kinases required to activate Akt and phosphorylate FOXOs, inhibiting DNA damage-induced apoptosis. Wild-type p53 activates nuclear Akt in an on/off fashion upon stress, whereas mutant p53 stimulates high basal Akt activity, indicating a fundamental difference. The nuclear p53-phosphoinositide signalosome is distinct from the canonical membrane-localized pathway and insensitive to PI3K inhibitors currently in the clinic, underscoring its therapeutic relevance.


1999 ◽  
Vol 19 (7) ◽  
pp. 5061-5072 ◽  
Author(s):  
Mirjana Andjelković ◽  
Sauveur-Michel Maira ◽  
Peter Cron ◽  
Peter J. Parker ◽  
Brian A. Hemmings

ABSTRACT Protein kinase B (PKB or Akt), a downstream effector of phosphoinositide 3-kinase (PI 3-kinase), has been implicated in insulin signaling and cell survival. PKB is regulated by phosphorylation on Thr308 by 3-phosphoinositide-dependent protein kinase 1 (PDK1) and on Ser473 by an unidentified kinase. We have used chimeric molecules of PKB to define different steps in the activation mechanism. A chimera which allows inducible membrane translocation by lipid second messengers that activate in vivo protein kinase C and not PKB was created. Following membrane attachment, the PKB fusion protein was rapidly activated and phosphorylated at the two key regulatory sites, Ser473 and Thr308, in the absence of further cell stimulation. This finding indicated that both PDK1 and the Ser473 kinase may be localized at the membrane of unstimulated cells, which was confirmed for PDK1 by immunofluorescence studies. Significantly, PI 3-kinase inhibitors prevent the phosphorylation of both regulatory sites of the membrane-targeted PKB chimera. Furthermore, we show that PKB activated at the membrane was rapidly dephosphorylated following inhibition of PI 3-kinase, with Ser473 being a better substrate for protein phosphatase. Overall, the results demonstrate that PKB is stringently regulated by signaling pathways that control both phosphorylation/activation and dephosphorylation/inactivation of this pivotal protein kinase.


Author(s):  
Huw D. Jones

Abstract Research into plant genetics often requires the suppression or complete knockout of gene expression to scientifically validate gene function. In addition, the phenotypes obtained from gene suppression can occasionally have commercial value for plant breeders. Until recently, the methodological choices to achieve these goals fell into two broad types: either some form of RNA-based gene silencing; or the screening of large numbers of natural or induced random genomic mutations. The more recent invention of gene editing as a tool for targeted mutation potentially gives researchers and plant breeders another route to block gene function. RNAi is widely used in animal and plant research and functions to silence gene expression by degrading the target gene transcript. Although RNAi offers unique advantages over genomic mutations, it often leads to the formation of a genetically modified organism (GMO), which for commercial activities has major regulatory and acceptance issues in some regions of the world. Traditional methods of generating genomic mutations are more laborious and uncertain to achieve the desired goals but possess a distinct advantage of not being governed by GMO regulations. Gene editing (GE) technologies have some of the advantages of both RNAi and classical mutation breeding in that they can be designed to give simple knockouts or to modulate gene expression more subtly. GE also has a more complex regulatory position, with some countries treating it as another conventional breeding method whilst the EU defines GE as a technique of genetic modification and applies the normal GMO authorization procedures. This chapter explores the pros and cons of RNAi alongside other methods of modulating gene function.


2019 ◽  
Vol 63 (1) ◽  
pp. 122-139 ◽  
Author(s):  
Junwei Wang ◽  
Hui Li ◽  
Guangchao He ◽  
Zhaoxing Chu ◽  
Kewen Peng ◽  
...  

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Longchuan Wu ◽  
Yu Chen ◽  
Jiao Yi ◽  
Yi Zhuang ◽  
Lei Cui ◽  
...  

Objective. To explore the mechanism of action of Bu-Fei-Yi-Shen formula (BFYSF) in treating chronic obstructive pulmonary disease (COPD) based on network pharmacology analysis and molecular docking validation. Methods. First of all, the pharmacologically active ingredients and corresponding targets in BFYSF were mined by the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database, the analysis platform, and literature review. Subsequently, the COPD-related targets (including the pathogenic targets and known therapeutic targets) were identified through the TTD, CTD, DisGeNet, and GeneCards databases. Thereafter, Cytoscape was employed to construct the candidate component-target network of BFYSF in the treatment of COPD. Moreover, the cytoHubba plug-in was utilized to calculate the topological parameters of nodes in the network; then, the core components and core targets of BFYSF in the treatment of COPD were extracted according to the degree value (greater than or equal to the median degree values for all nodes in the network) to construct the core network. Further, the Autodock vina software was adopted for molecular docking study on the core active ingredients and core targets, so as to verify the above-mentioned network pharmacology analysis results. Finally, the Omicshare database was applied in enrichment analysis of the biological functions of core targets and the involved signaling pathways. Results. In the core component-target network of BFYSF in treating COPD, there were 30 active ingredients and 37 core targets. Enrichment analysis suggested that these 37 core targets were mainly involved in the regulation of biological functions, such as response to biological and chemical stimuli, multiple cellular life processes, immunity, and metabolism. Besides, multiple pathways, including IL-17, Toll-like receptor (TLR), TNF, and HIF-1, played certain roles in the effect of BFYSF on treating COPD. Conclusion. BFYSF can treat COPD through the multicomponent, multitarget, and multipathway synergistic network, which provides basic data for intensively exploring the mechanism of action of BFYSF in treating COPD.


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