Targeting SPARC expression decreases glioma cellular survival and invasion associated with reduced activities of FAK and ILK kinases

AbstractAberrant cholesterol homeostasis is implicated in the pathogenesis of amyotrophic lateral sclerosis (ALS), a fatal neuromuscular disease that is due to motor neuron (MN) death. Cellular toxicity from excess cholesterol is averted when it is enzymatically oxidized to oxysterols and bile acids (BAs) to promote its removal. In contrast, the auto oxidation of excess cholesterol is often detrimental to cellular survival. Although oxidized metabolites of cholesterol are altered in the blood and CSF of ALS patients, it is unknown if increased cholesterol oxidation occurs in the SC during ALS, and if exposure to oxidized cholesterol metabolites affects human MN viability. Here, we show that in the SOD1G93A mouse model of ALS that several oxysterols, BAs and auto oxidized sterols are increased in the lumbar SC, plasma, and feces during disease. Similar changes in cholesterol oxidation were found in the cervical SC of sporadic ALS patients. Notably, auto-oxidized sterols, but not oxysterols and BAs, were toxic to iPSC derived human MNs. Thus, increased cholesterol oxidation is a manifestation of ALS and non-regulated sterol oxidation likely contributes to MN death. Developing therapeutic approaches to restore cholesterol homeostasis in the SC may lead to a treatment for ALS.

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Intracellular Ionic Strength Sensing Using NanoLuc

International Journal of Molecular Sciences ◽

10.3390/ijms22020677 ◽

2021 ◽

Vol 22 (2) ◽

pp. 677

Author(s):

Tausif Altamash ◽

Wesam Ahmed ◽

Saad Rasool ◽

Kabir H. Biswas

Keyword(s):

Thermal Stability ◽

Phase Separation ◽

Drug Discovery ◽

Ionic Strength ◽

Cellular Signaling ◽

Live Cells ◽

Protein Activity ◽

Cellular Survival ◽

Cellular Processes ◽

Wide Range

Intracellular ionic strength regulates myriad cellular processes that are fundamental to cellular survival and proliferation, including protein activity, aggregation, phase separation, and cell volume. It could be altered by changes in the activity of cellular signaling pathways, such as those that impact the activity of membrane-localized ion channels or by alterations in the microenvironmental osmolarity. Therefore, there is a demand for the development of sensitive tools for real-time monitoring of intracellular ionic strength. Here, we developed a bioluminescence-based intracellular ionic strength sensing strategy using the Nano Luciferase (NanoLuc) protein that has gained tremendous utility due to its high, long-lived bioluminescence output and thermal stability. Biochemical experiments using a recombinantly purified protein showed that NanoLuc bioluminescence is dependent on the ionic strength of the reaction buffer for a wide range of ionic strength conditions. Importantly, the decrease in the NanoLuc activity observed at higher ionic strengths could be reversed by decreasing the ionic strength of the reaction, thus making it suitable for sensing intracellular ionic strength alterations. Finally, we used an mNeonGreen–NanoLuc fusion protein to successfully monitor ionic strength alterations in a ratiometric manner through independent fluorescence and bioluminescence measurements in cell lysates and live cells. We envisage that the biosensing strategy developed here for detecting alterations in intracellular ionic strength will be applicable in a wide range of experiments, including high throughput cellular signaling, ion channel functional genomics, and drug discovery.

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Mechanistic Modelling of DNA Repair and Cellular Survival Following Radiation-Induced DNA Damage

Scientific Reports ◽

10.1038/srep33290 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 36

Author(s):

Stephen J. McMahon ◽

Jan Schuemann ◽

Harald Paganetti ◽

Kevin M. Prise

Keyword(s):

Dna Damage ◽

Dna Repair ◽

Mechanistic Modelling ◽

Cellular Survival ◽

Radiation Induced

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Responses of Bacillus subtilis to Hypotonic Challenges: Physiological Contributions of Mechanosensitive Channels to Cellular Survival

Applied and Environmental Microbiology ◽

10.1128/aem.01573-07 ◽

2008 ◽

Vol 74 (8) ◽

pp. 2454-2460 ◽

Cited By ~ 50

Author(s):

Tamara Hoffmann ◽

Clara Boiangiu ◽

Susanne Moses ◽

Erhard Bremer

Keyword(s):

Bacillus Subtilis ◽

Mutational Analysis ◽

Mechanosensitive Channels ◽

High Osmolarity ◽

Cellular Survival ◽

Genes Encoding ◽

Quadruple Mutant ◽

Rapid Transition ◽

A Minor ◽

Small Conductance

ABSTRACT Mechanosensitive channels are thought to function as safety valves for the release of cytoplasmic solutes from cells that have to manage a rapid transition from high- to low-osmolarity environments. Subsequent to an osmotic down-shock of cells grown at high osmolarity, Bacillus subtilis rapidly releases the previously accumulated compatible solute glycine betaine in accordance with the degree of the osmotic downshift. Database searches suggest that B. subtilis possesses one copy of a gene for a mechanosensitive channel of large conductance (mscL) and three copies of genes encoding proteins that putatively form mechanosensitive channels of small conductance (yhdY, yfkC, and ykuT). Detailed mutational analysis of all potential channel-forming genes revealed that a quadruple mutant (mscL yhdY yfkC ykuT) has no growth disadvantage in high-osmolarity media in comparison to the wild type. Osmotic down-shock experiments demonstrated that the MscL channel is the principal solute release system of B. subtilis, and strains with a gene disruption in mscL exhibited a severe survival defect upon an osmotic down-shock. We also detected a minor contribution of the SigB-controlled putative MscS-type channel-forming protein YkuT to cellular survival in an mscL mutant. Taken together, our data revealed that mechanosensitive channels of both the MscL and MscS types play pivotal roles in managing the transition of B. subtilis from hyper- to hypo-osmotic environments.

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Epithelial and fibroblast SPARC expression patterns in oral leukoplakia and oral squamous cell carcinoma

Oral Surgery Oral Medicine Oral Pathology and Oral Radiology ◽

10.1016/j.oooo.2021.10.019 ◽

2021 ◽

Author(s):

Sopee Poomsawat ◽

Theerachai Kosanwat ◽

Ounruean Meesakul ◽

Sirima Sanguansin

Keyword(s):

Squamous Cell Carcinoma ◽

Oral Squamous Cell Carcinoma ◽

Cell Carcinoma ◽

Squamous Cell ◽

Expression Patterns ◽

Oral Leukoplakia ◽

Sparc Expression

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Interplay between Endoplasmic Reticular Stress and Survivin in Colonic Epithelial Cells

Cells ◽

10.3390/cells7100171 ◽

2018 ◽

Vol 7 (10) ◽

pp. 171 ◽

Cited By ~ 8

Author(s):

Rohit Gundamaraju ◽

Ravichandra Vemuri ◽

Wai Chin Chong ◽

Stephen Myers ◽

Shaghayegh Norouzi ◽

...

Keyword(s):

Cell Death ◽

Cancer Cells ◽

Inflammatory Markers ◽

Caspase 3 ◽

Annexin V ◽

Parp Cleavage ◽

Cellular Survival ◽

Unfolded Protein ◽

Proliferative Assay ◽

The Unfolded Protein Response

Sustained endoplasmic reticular stress (ERS) is implicated in aggressive metastasis of cancer cells and increased tumor cell proliferation. Cancer cells activate the unfolded protein response (UPR), which aids in cellular survival and adaptation to harsh conditions. Inhibition of apoptosis, in contrast, is a mechanism adopted by cancer cells with the help of the inhibitor of an apoptosis (IAP) class of proteins such as Survivin to evade cell death and gain a proliferative advantage. In this study, we aimed to reveal the interrelation between ERS and Survivin. We initially verified the expression of Survivin in Winnie (a mouse model of chronic ERS) colon tissues by using immunohistochemistry (IHC) and immunofluorescence (IF) in comparison with wild type Blk6 mice. Additionally, we isolated the goblet cells and determined the expression of Survivin by IF and protein validation. Tunicamycin was utilized at a concentration of 10 µg/mL to induce ERS in the LS174T cell line and the gene expression of the ERS markers was measured. This was followed by determination of inflammatory cytokines. Inhibition of ERS was carried out by 4Phenyl Butyric acid (4PBA) at a concentration of 10 mM to assess whether there was a reciprocation effect. The downstream cell death assays including caspase 3/7, Annexin V, and poly(ADP-ribose) polymerase (PARP) cleavage were evaluated in the presence of ERS and absence of ERS, which was followed by a proliferative assay (EdU click) with and without ERS. Correspondingly, we inhibited Survivin by YM155 at a concentration of 100 nM and observed the succeeding ERS markers and inflammatory markers. We also verified the caspase 3/7 assay. Our results demonstrate that ERS inhibition not only significantly reduced the UPR genes (Grp78, ATF6, PERKandXBP1) along with Survivin but also downregulated the inflammatory markers such as IL8, IL4, and IL6, which suggests a positive correlation between ERS and the inhibition of apoptosis. Furthermore, we provided evidence that ERS inhibition promoted apoptosis in LS174T cells and shortened the proliferation rate. Moreover, Survivin inhibition by YM155 led to a comparable effect as that of ERS inhibition, which includes attenuation of ERS genes and inflammatory markers as well as the promotion of programmed cell death via the caspase 3/7 pathway. Together, our results propose the interrelation between ERS and inhibition of apoptosis assigning a molecular and therapeutic target for cancer treatment.

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Computer Programs for the Analysis of Cellular Survival Data

Radiation Research ◽

10.2307/3577260 ◽

1987 ◽

Vol 112 (2) ◽

pp. 331 ◽

Cited By ~ 110

Author(s):

Norman Albright

Keyword(s):

Survival Data ◽

Computer Programs ◽

Cellular Survival

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The ataxia telangiectasia group D associated gene confers a cellular survival advantage in pancreatic adenocarcinoma

Journal of Surgical Research ◽

10.1016/j.jss.2003.08.131 ◽

2003 ◽

Vol 114 (2) ◽

pp. 240

Author(s):

C.E. Binkley ◽

M.A. Davis ◽

L. Zhang ◽

T.S. Lawrence ◽

C.D. Logsdon ◽

...

Keyword(s):

Pancreatic Adenocarcinoma ◽

Ataxia Telangiectasia ◽

Survival Advantage ◽

Cellular Survival ◽

Group D

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Cell Death and Survival Pathways Involving ATM Protein Kinase

Genes ◽

10.3390/genes12101581 ◽

2021 ◽

Vol 12 (10) ◽

pp. 1581

Author(s):

Toshihiko Aki ◽

Koichi Uemura

Keyword(s):

Cell Death ◽

Protein Kinase ◽

Genotoxic Stress ◽

Short Review ◽

Research Progress ◽

Cellular Protection ◽

Cellular Survival ◽

Cell Death Pathways ◽

Wide Range ◽

Atm Protein

Cell death is the ultimate form of cellular dysfunction, and is induced by a wide range of stresses including genotoxic stresses. During genotoxic stress, two opposite cellular reactions, cellular protection through DNA repair and elimination of damaged cells by the induction of cell death, can occur in both separate and simultaneous manners. ATM (ataxia telangiectasia mutated) kinase (hereafter referred to as ATM) is a protein kinase that plays central roles in the induction of cell death during genotoxic stresses. It has long been considered that ATM mediates DNA damage-induced cell death through inducing apoptosis. However, recent research progress in cell death modality is now revealing ATM-dependent cell death pathways that consist of not only apoptosis but also necroptosis, ferroptosis, and dysfunction of autophagy, a cellular survival mechanism. In this short review, we intend to provide a brief outline of cell death mechanisms in which ATM is involved, with emphasis on pathways other than apoptosis.

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