scholarly journals A selective and rapid cell-permeable inhibitor of human caspase-3

2019 ◽  
Author(s):  
Angelo Solania ◽  
Gonzalo E. González-Páez ◽  
Dennis W. Wolan

ABSTRACTThe individual roles and overlapping functionalities the twelve human caspases have during apoptosis and other cellular processes remain poorly resolved primarily due to a lack of chemical tools. Here we present a new selective caspase-3 inhibitor, termed Ac-ATS010-KE, with rapid and irreversible binding kinetics. Relative to previously designed caspase-3-selective molecules that have tremendously abated inhibitory rates and thus limited use in biological settings, the improved kinetics of Ac-ATS010-KE permit its use in a cell-based capacity. We demonstrate that Ac-ATS010-KE prevents apoptosis with comparable efficacy to the general caspase inhibitor Ac-DEVD-KE and surprisingly does so without side-chain methylation. This observation is in contrast to the well-established peptide modification strategy typically employed for improving cellular permeability. Ac-ATS010-KE protects against extrinsic apoptosis, which demonstrates the utility of a thiophene carboxylate leaving group in biological settings, challenges the requisite neutralization of free carboxylic acids to improve cell permeability, and provides a tool-like compound to interrogate the role of caspase-3 in a variety of cellular processes.

Cells ◽  
2018 ◽  
Vol 7 (9) ◽  
pp. 133 ◽  
Author(s):  
Julia Concetti ◽  
Caroline L Wilson

Current evidence strongly suggests that aberrant activation of the NF-κB signalling pathway is associated with carcinogenesis. A number of key cellular processes are governed by the effectors of this pathway, including immune responses and apoptosis, both crucial in the development of cancer. Therefore, it is not surprising that dysregulated and chronic NF-κB signalling can have a profound impact on cellular homeostasis. Here we discuss NFKB1 (p105/p50), one of the five subunits of NF-κB, widely implicated in carcinogenesis, in some cases driving cancer progression and in others acting as a tumour-suppressor. The complexity of the role of this subunit lies in the multiple dimeric combination possibilities as well as the different interacting co-factors, which dictate whether gene transcription is activated or repressed, in a cell and organ-specific manner. This review highlights the multiple roles of NFKB1 in the development and progression of different cancers, and the considerations to make when attempting to manipulate NF-κB as a potential cancer therapy.


Blood ◽  
1993 ◽  
Vol 82 (8) ◽  
pp. 2537-2545 ◽  
Author(s):  
DD Hickstein ◽  
E Grunvald ◽  
G Shumaker ◽  
DM Baker ◽  
AL Back ◽  
...  

Abstract The CD11b/CD18 leukocyte integrin molecule mediates diverse neutrophil adherence-related functions, including cell:cell and cell:extracellular matrix attachments. To study the individual role of this leukocyte integrin in cell adherence in hematopoietic cells, we expressed the CD11b/CD18 complex on the surface of K562 cells, a cell line derived from an individual with chronic myelogenous leukemia in blast crisis. We used an amphotrophic retroviral vector designated LCD18SN, harboring the complete coding sequence for the CD18 subunit, to transfer the CD18 cDNA into K562 cells and select stable cell lines. The CD11b subunit in the expression plasmid pREP4 was transfected into these K562/CD18 cells by electroporation and stable cell clones were selected. These K562 cells possessed RNA and intracellular protein for each subunit, and they expressed the CD11b/CD18 heterodimer on the cell surface. When CD11b/CD18 expressing K562 cells were stimulated with phorbol myristate acetate (50 ng/mL) for 24 to 48 hours, these K562 cells formed dense cell:cell aggregates. This homotypic aggregation required both activation of the CD11b/CD18 complex and the induction of the counter- receptor for CD11b/CD18 on the conjugate cell. This cell line will (1) enable the structure-function relationships between cell activation and homotypic adherence to be assessed, (2) provide the opportunity to identify accessory molecules required for activation of the CD11b/CD18 complex, and (3) facilitate the identification of novel ligands for the CD11b/CD18 complex.


Blood ◽  
1993 ◽  
Vol 82 (8) ◽  
pp. 2537-2545
Author(s):  
DD Hickstein ◽  
E Grunvald ◽  
G Shumaker ◽  
DM Baker ◽  
AL Back ◽  
...  

The CD11b/CD18 leukocyte integrin molecule mediates diverse neutrophil adherence-related functions, including cell:cell and cell:extracellular matrix attachments. To study the individual role of this leukocyte integrin in cell adherence in hematopoietic cells, we expressed the CD11b/CD18 complex on the surface of K562 cells, a cell line derived from an individual with chronic myelogenous leukemia in blast crisis. We used an amphotrophic retroviral vector designated LCD18SN, harboring the complete coding sequence for the CD18 subunit, to transfer the CD18 cDNA into K562 cells and select stable cell lines. The CD11b subunit in the expression plasmid pREP4 was transfected into these K562/CD18 cells by electroporation and stable cell clones were selected. These K562 cells possessed RNA and intracellular protein for each subunit, and they expressed the CD11b/CD18 heterodimer on the cell surface. When CD11b/CD18 expressing K562 cells were stimulated with phorbol myristate acetate (50 ng/mL) for 24 to 48 hours, these K562 cells formed dense cell:cell aggregates. This homotypic aggregation required both activation of the CD11b/CD18 complex and the induction of the counter- receptor for CD11b/CD18 on the conjugate cell. This cell line will (1) enable the structure-function relationships between cell activation and homotypic adherence to be assessed, (2) provide the opportunity to identify accessory molecules required for activation of the CD11b/CD18 complex, and (3) facilitate the identification of novel ligands for the CD11b/CD18 complex.


2016 ◽  
Vol 7 (5-6) ◽  
pp. 311-319 ◽  
Author(s):  
Daniel Senfter ◽  
Sibylle Madlener ◽  
Georg Krupitza ◽  
Robert M. Mader

AbstractIn the last decade, microRNAs (miRs or miRNAs) became of great interest in cancer research due to their multifunctional and active regulation in a variety of vital cellular processes. In this review, we discuss the miR-200 family, which is composed of five members (miR-141, miR-200a/200b/200c and miR-429). Although being among the best investigated miRNAs in the field, there are still many open issues. Here, we describe the potential role of miR-200 as prognostic and/or predictive biomarker, its influence on motility and cell migration as well as its role in epithelial to mesenchymal transition (EMT) and metastasis formation in different tumour types. Recent studies also demonstrated the influence of miR-200 on drug resistance and described a correlation between miR-200 expression levels and overall survival of patients. Despite intense research in this field, the full role of the miR-200 family in cancer progression and metastasis is not completely understood and seems to differ between different tumour types and different cellular backgrounds. To elucidate these differences further, a finer characterisation of the role of the individual miRNA-200 family members is currently under investigation.


Biomolecules ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 614 ◽  
Author(s):  
Lisamaria Bracher ◽  
Iolanda Ferro ◽  
Carlos Pulido-Quetglas ◽  
Marc-David Ruepp ◽  
Rory Johnson ◽  
...  

Regulatory non-protein coding RNAs perform a remarkable variety of complex biological functions. Previously, we demonstrated a role of the human non-coding vault RNA1-1 (vtRNA1-1) in inhibiting intrinsic and extrinsic apoptosis in several cancer cell lines. Yet on the molecular level, the function of the vtRNA1-1 is still not fully clear. Here, we created HeLa knock-out cell lines revealing that prolonged starvation triggers elevated levels of apoptosis in the absence of vtRNA1-1 but not in vtRNA1-3 knock-out cells. Next-generation deep sequencing of the mRNome identified the PI3K/Akt pathway and the ERK1/2 MAPK cascade, two prominent signaling axes, to be misregulated in the absence of vtRNA1-1 during starvation-mediated cell death conditions. Expression of vtRNA1-1 mutants identified a short stretch of 24 nucleotides of the vtRNA1-1 central domain as being essential for successful maintenance of apoptosis resistance. This study describes a cell signaling-dependent contribution of the human vtRNA1-1 to starvation-induced programmed cell death.


2014 ◽  
Vol 76 (9) ◽  
pp. 576-581
Author(s):  
Robert D. Seager

In learning genetics, many students misunderstand and misinterpret what “dominance” means. Understanding is easier if students realize that dominance is not a mechanism, but rather a consequence of underlying cellular processes. For example, metabolic pathways are often little affected by changes in enzyme concentration. This means that enzyme-producing alleles usually show complete dominance. For genes producing nonenzymatic proteins such as collagen or hemoglobin, the amount of product matters, and dominance relationships are more complicated. Furthermore, with hemoglobin, dominance can change depending on what aspect of the phenotype is being studied and on the environmental conditions. X-linked genes are a special case, whether enzymatic or not. Because of X-chromosome inactivation, only one X-linked allele can be active in a cell, which means that the concept of dominance cannot be applied at the cellular level. Instead, a type of dominance is demonstrated at the individual level; but even so, dominant traits may fail to be expressed, and recessive traits can be expressed. Teaching not only what is happening but why it's happening will give students a deeper understanding, not only of dominance relationships, but of the underlying cellular processes as well.


2021 ◽  
Vol 22 (18) ◽  
pp. 9945
Author(s):  
Luisa Galla ◽  
Nicola Vajente ◽  
Diana Pendin ◽  
Paola Pizzo ◽  
Tullio Pozzan ◽  
...  

Calcium (Ca2+) exerts a pivotal role in controlling both physiological and detrimental cellular processes. This versatility is due to the existence of a cell-specific molecular Ca2+ toolkit and its fine subcellular compartmentalization. Study of the role of Ca2+ in cellular physiopathology greatly benefits from tools capable of quantitatively measuring its dynamic concentration ([Ca2+]) simultaneously within organelles and in the cytosol to correlate localized and global [Ca2+] changes. To this aim, as nucleoplasm Ca2+ changes mirror those of the cytosol, we generated a novel nuclear-targeted version of a Föster resonance energy transfer (FRET)-based Ca2+ probe. In particular, we modified the previously described nuclear Ca2+ sensor, H2BD3cpv, by substituting the donor ECFP with mCerulean3, a brighter and more photostable fluorescent protein. The thorough characterization of this sensor in HeLa cells demonstrated that it significantly improved the brightness and photostability compared to the original probe, thus obtaining a probe suitable for more accurate quantitative Ca2+ measurements. The affinity for Ca2+ was determined in situ. Finally, we successfully applied the new probe to confirm that cytoplasmic and nucleoplasmic Ca2+ levels were similar in both resting conditions and upon cell stimulation. Examples of simultaneous monitoring of Ca2+ signal dynamics in different subcellular compartments in the very same cells are also presented.


1998 ◽  
Vol 53 (5-6) ◽  
pp. 352-358 ◽  
Author(s):  
Yutaka Takeuchi ◽  
Hiroshi Ohashi ◽  
Paul J. Birckbichler ◽  
Takashi Ikejim

Abstract Tissue type (type 2) transglutaminase (TGase, EC 2.3.2.13) has been implicated in various cellular processes including cell death. In order to better understand the role of this enzyme in cell death, human melanocytic A375-S2 cells were treated with sphingosine, a cell-signaling mediator. During the rapid onset of cytotoxicity caused by this lipidic agent, tissue TGase was translocated from the cytoplasm to the cell nuclei. This observation was further remarked in relevance to its previously undescribed activity for DNA degradation. The DNA hydrolytic activity associated with tissue TGase was dependent on Mg2+ in contrast to the Ca2+ requirement for the classical cross-linking acrivity of TGase, and was inhibited by Zn2+. Based on the results shown here, we propose a novel aspect of tissue TGase in cell death.


2021 ◽  
Author(s):  
Noel Blanco-Touriñán ◽  
David Esteve-Bruna ◽  
Antonio Serrano-Mislata ◽  
Rosa María Esquinas ◽  
Francesca Resentini ◽  
...  

SummaryThe prefoldin complex (PFDc) was identified in humans as co-chaperone of the cytosolic chaperonin TRiC/CCT. It is conserved in eukaryotes and is composed of subunits PFD1 to 6. PFDc-TRiC/CCT operates folding actin and tubulins. In addition to this function, PFDs participate in a wide range of cellular processes, both in the cytoplasm and in the nucleus, and their malfunction cause developmental alterations and disease in animals, and altered growth and environmental responses in yeast and plants. Genetic analyses in yeast indicate that not all functions performed by PFDs require the participation of the canonical complex. The lack of systematic genetic analyses in higher eukaryotes makes it difficult to discern whether PFDs participate in a particular process as canonical complex or in alternative configurations, i.e. as individual subunits or in other complexes. To tackle this question, and on the premise that the canonical complex cannot be formed if one subunit is missing, we have prepared an Arabidopsis mutant deficient in the six prefoldins, and compared various growth and environmental responses with those of the individual pfd. In this way, we demonstrate that the PFDc is required to delay flowering, for seed germination, or to respond to high salt stress, whereas two or more PFDs redundantly attenuate the response to osmotic stress. A coexpression analysis of differentially expressed genes in the sextuple mutant has identified several transcription factors, such as ABI5 or PIF4, acting downstream of PFDs. Furthermore, it has made possible to assign novel roles for PFDs, for instance, in the response to warm temperature.


2019 ◽  
Vol 24 (5) ◽  
pp. 14-15
Author(s):  
Jay Blaisdell ◽  
James B. Talmage

Abstract Ratings for “non-specific chronic, or chronic reoccurring, back pain” are based on the diagnosis-based impairment method whereby an impairment class, usually representing a range of impairment values within a cell of a grid, is selected by diagnosis and “specific criteria” (key factors). Within the impairment class, the default impairment value then can be modified using non-key factors or “grade modifiers” such as functional history, physical examination, and clinical studies using the net adjustment formula. The diagnosis of “nonspecific chronic, or chronic reoccurring, back pain” can be rated in class 0 and 1; the former has a default value of 0%, and the latter has a default value of 2% before any modifications. The key concept here is that the physician believes that the patient is experiencing pain, yet there are no related objective findings, most notably radiculopathy as distinguished from “nonverifiable radicular complaints.” If the individual is found not to have radiculopathy and the medical record shows that the patient has never had clinically verifiable radiculopathy, then the diagnosis of “intervertebral disk herniation and/or AOMSI [alteration of motion segment integrity] cannot be used.” If the patient is asymptomatic at maximum medical improvement, then impairment Class 0 should be chosen, not Class 1; a final whole person impairment rating of 1% indicates incorrect use of the methodology.


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