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Background: Metabolic plasticity gives cancer cells the ability to shift between signaling pathways to facilitate their growth and survival. This study investigates the role of glucose deprivation in the presence and absence of beta-hydroxybutyrate (BHB) in growth, death, oxidative stress and the stemness features of lung cancer cells., Methods and Results: A549 cells were exposed to various glucose conditions, both with and without beta-hydroxybutyrate (BHB), to evaluate their effects on apoptosis, mitochondrial membrane potential, reactive oxygen species (ROS) levels using flow cytometry, and the expression of CD133, CD44, SOX-9, and β-Catenin through Quantitative PCR. The activity of superoxide dismutase, glutathione peroxidase, and malondialdehyde was assessed using colorimetric assays. Treatment with therapeutic doses of BHB triggered apoptosis in A549 cells, particularly in cells adapted to glucose deprivation. The elevated ROS levels, combined with reduced levels of SOD and GPx, indicate that oxidative stress contributes to the cell arrest induced by BHB. Notably, BHB treatment under glucose-restricted conditions notably decreased CD133 expression, suggesting a potential inhibition of cell survival through the downregulation of CD133 levels. Additionally, the simultaneous decrease in mitochondrial membrane potential and increase in ROS levels indicate the potential for creating oxidative stress conditions to impede tumor cell growth in such environmental settings., Conclusion: The induced cell death, oxidative stress and mitochondria impairment beside attenuated levels of cancer stem cell markers following BHB administration emphasize on the distinctive role of metabolic plasticity of cancer cells and propose possible therapeutic approaches to control cancer cell growth through metabolic fuels., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Background: Considering the advantages of using medicinal herbs as supplementary treatments to sensitize conventional anti-cancer drugs, studying functional mechanisms and regulatory effects of Echinacea purpurea (as a non-cannabinoid plant) and Cannabis sativa (as a cannabinoid plant) are timely and required. The potential effects of such herbs on lung cancer cell growth, apoptosis, cell cycle distribution, cellular reactive oxygen species (ROS) level, caspase activity and their cannabinomimetic properties on the CB2 receptor are addressed in the current study., Methods: The cytotoxic effect of both herb extracts on the growth of lung cancer cells (A549) was assessed using the MTT assay. The annexin-V-FITC staining and propidium iodide (PI) staining methods were applied for the detection of apoptosis and cell cycle distribution using flow cytometry. The cellular level of ROS was measured using 7'-dichlorofluorescin diacetate (DCFH-DA) as a fluorescent probe in flow cytometry. The caspase 3 activity was assessed using a colorimetric assay Kit., Results: Echinacea purpurea (EP) root extract induced a considerable decrease in A549 viable cells, showing a time and dose-dependent response. The cell toxicity of EP was accompanied by induction of early apoptosis and cell accumulation at the sub G1 phase of the cell cycle. The elevation of cellular ROS level and caspase 3 activity indicate ROS-induced caspase-dependent apoptosis following the treatment of A549 cells by EP extract. The observed effects of EP extract on A549 growth and death were abrogated following blockage of CB2 using AM630, a specific antagonist of the CB2 receptor. Increasing concentrations of Cannabis sativa (CS) induced A549 cell death in a time-dependent manner, followed by induction of early apoptosis, cell cycle arrest at sub G1 phase, elevation of ROS level, and activation of caspase 3. The CB2 blockage caused attenuation of CS effects on A549 cell death which revealed consistency with the effects of EP extract on A549 cells., Conclusions: The pro-apoptotic effects of EP and CS extracts on A549 cells and their possible regulatory role of CB2 activity might be attributed to metabolites of both herbs. These effects deserve receiving more attention as alternative anti-cancer agents.

Background: Visfatin is a novel adipokine and proinflammatory cytokine which is implicated in breast cancer progression. The exact proliferative and anti-apoptotic mechanisms of visfatin are still under debate. In this study, the effect of extracellular visfatin on proliferation and apoptosis of breast cancer cells were investigated considering key regulatory molecules in these procedures., Methods: BrdU (Bromodeoxyuridine) experiment was used to assess cell proliferation in response to visfatin treatment. Cell viability and apoptosis were assessed using MTT assay and flowcytometry, respectively. Phosphorylation levels of AKT and ERK1/2 as well as survivin levels and Poly ADP ribose polymerase (PARP) cleavage were investigated by western blot analysis., Results: Visfatin induced proliferation of MCF-7 and MDA-MB-231 cells, an effect that was repressed by using AKT and ERK1/2 inhibitors, indicating involvement of these two signaling pathways in the proliferative effect of visfatin. Similarly, phosphorylation of AKT and ERK1/2 were elevated by visfatin treatment. On the other hand, visfatin improved cell viability and prevented TNF-α-induced apoptosis as well as PARP cleavage. Visfatin also exerted a protective effect on survivin., Conclusion: The results of this study suggest that visfatin induces breast cancer cell proliferation through AKT/PI3K and ERK/MAPK activation and protects against apoptosis in these cells. Thus increased visfatin levels may augment breast cancer development and attenuate treatment efficiency in breast cancer patients., (Copyright © 2017 Elsevier Inc. All rights reserved.)

NAD is mainly biosynthesized by the enzymatic action of nicotinamide phosphoribosyltransferase (NAMPT) through the salvage pathway. NAD is indispensable for the proper function and metabolism of all living cells, including cancer cells. Our previous researches revealed that inhibition of NAMPT by miRNA (miR) could suppress NAD levels and thereby hinder the growth and promotion of breast cancer (BC). Therefore, the current study was undertaken to investigate the inhibitory effects of miR-613 on NAMPT and BC cells' survival. Bioinformatics analysis and luciferase reporter assay confirmed that NAMPT 3′-untranslated region is a direct target for miR-613. The expression of miR-613 was noticed to be significantly decreased in both clinical tissue samples and BC cells by real-time PCR. Following transfection with miR-613 mimic, the expression of miR-613 was elevated in the BC cells leading to inhibition of NAMPT expression at both mRNA and protein level as measured by real-time PCR and western blotting, respectively. Inhibition of NAMPT led to a remarkable reduction in the concentration of NAD in the BC cells. The transfection also declined cell viability roughly 40% in MD Anderson-Metastatic Breast-231 (MDA-MB-231) cells. Consistently, the apoptosis rate was remarkably increased, around 65% in these cells as assayed by labeling the cells with Annexin V-fluorescein isothiocyanate (FITC) and Propidium Iodide. Targeting the NAMPT-mediated NAD salvage pathway by miR-613 is a novel approach for managing BC, which is worth further investigation. [ABSTRACT FROM AUTHOR]

Background: Nicotinamide phosphoribosyltransferase (NAMPT) enzyme acts as the major enzyme in the nicotinamide adenine dinucleotide (NAD) synthesis salvage pathway. Deregulation of NAD could be associated with progression of several cancers such as breast cancer. Here, the consequence of NAMPT inhibition by miR-154 was investigated on breast cancer cells.Methods: MDA-MB-231 and MCF-7 cancer cell lines were transfected with the mimic and inhibitors of miR-154-5p and their corresponding negative controls. Consequently, levels of NAMPT and NAD were assayed employing qRT-PCR, Western blotting and enzymatic method, respectively. Subsequently, flow cytometry and colorimetric methods were performed to evaluate apoptosis and cell viability. Bioinformatics analyses as well as luciferase assay were done to investigate whether the 3'-UTR of NAMPT is directly targeted by miR-154.Results: According to the obtained results, NAMPT was recognized as a target for binding of miR-154 and the levels of this miRNA was inversely associated with both mRNA and protein levels of NAMPT in breast cancer cell lines. Functionally, miR-154 inhibited the NAD salvage pathway leading to a remarkable decrease in cell viability and increased rate of cell death. When breast cancer cells were simultaneously treated with doxorubicin and miR-154 mimic, cell viability was considerably reduced compared to treatment with doxorubicin alone in both cell lines.Conclusions: It was concluded that the inhibition of NAD production by miR-154 might be introduced as an appropriate therapeutic approach in order to improve breast cancer outcome either alone or in combination with other conventional chemotherapeutic agents. [ABSTRACT FROM AUTHOR]

Breast cancer (BC) is the most prevalent cause of cancer-related death in women worldwide. BC is frequently associated with elevated levels of nicotinamide phosphoribosyltransferase (NAMPT) in blood and tumor tissue. MicroRNA-494 (miR-494) has been described to play key anti-tumor roles in human cancers. The aim of the present study was to investigate the inhibitory effect of miR-494 on NAMPT-mediated viability of BC cells. In this experimental study, MCF-7 and MDA-MB-231 cells were cultured and then transfected with miR-494 mimic, miR-494 inhibitor and their negative controls. The mRNA and protein expression of NAMPT were assessed using real-time PCR and Western blotting, respectively. Subsequently, intracellular NAD levels were determined by a colorimetric method. Finally, cell apoptosis was examined by flow cytometry. Bioinformatics evaluations predicted NAMPT as a miR-494 target gene which was confirmed by luciferase reporter assay. Our results showed an inverse relationship between the expression of miR-494 and NAMPT in both MCF-7 and MDA-MB-231 cell lines. miR-494 significantly down-regulated NAMPT mRNA and protein expression and was also able to reduce the cellular NAD content. Cell viability was decreased following miR-494 up-regulation. In addition, apoptosis was induced in MCF-7 and MDA-MB-231 cells by miR-494 mimic. Our findings indicate that miR-494 acts as a tumor suppressor and has an important effect in suppressing the growth of BC cells through NAMPT. Therefore, miR-494 might be considered as a novel therapeutic target for the management of human breast cancer. [ABSTRACT FROM AUTHOR]

Nicotinamide phosphoribosyltransferase (NAMPT), a rate-limiting enzyme involved in nicotinamide adenine dinucleotide (NAD) salvage pathway, is overexpressed in many human malignancies such as breast cancer. This enzyme plays a critical role in survival and growth of cancer cells. MicroRNAs (miRNAs) are among the most important regulators of gene expression, and serve as potential targets for diagnosis, prognosis, and therapy of breast cancer. Therefore, the aim of this study was to assess the effect of NAMPT inhibition by miR-381 on breast cancer cell survival. MCF-7 and MDA-MB-231 cancer cell lines were transfected with miR-381 mimic, inhibitor, and their corresponding negative controls (NCs). Subsequently, the level of NAMPT and NAD was assessed using real-time PCR, immuno-blotting, and enzymatic methods, respectively. In order to evaluate apoptosis, cells were labelled with Annexin V-FITC and propidium iodide and analyzed by flow cytometry. Bioinformatics analysis was performed to recognize whether NAMPT 3'-untranslated region (UTR) is a direct target of miR-381 and the results were authenticated by the luciferase reporter assay using a vector containing the 3'-UTR sequence of NAMPT. Our results revealed that the 3'-UTR of NAMPT was a direct target of miR-381 and its up-regulation decreased NAMPT gene and protein expression, leading to a notable reduction in intracellular NAD and subsequently cell survival and induction of apoptosis. It can be concluded that miR-381 has a vital role in tumor suppression by down-regulation of NAMPT, and it can be a promising candidate for breast cancer therapy. [ABSTRACT FROM AUTHOR]

Fibrosis as the hallmark of adipose tissue dysfunction which is associated with insulin resistance and type 2 diabetes, results from deposition of excess extra cellular matrix components like collagen and increased cell death. Here we investigated the effect of antidiabetic drug, Metformin, on the factors that play role in fibrosis such as; integrin/ERK pathway, collagen VI, MMP2, MMP9, apoptosis markers including DAPK1, DAPK3, DAP, SIVA, necrosis markers including RIPK1, RIPK3, and MLKL in insulin resistant and hypertrophied adipocytes. 3T3-L1 adipocytes after differentiation to insulin resistant and hypertrophied cells, treated with Metformin, and the gene expression of aforementioned factors assayed by real time PCR. The protein expression of collagen VI and ERK assayed by western blotting. The expression of integrins changed from 0.5 to 6-fold in hypertrophied adipocyte versus adipocyte. Apoptosis and necrosis markers increased >1.5-fold in insulin resistant and hypertrophied adipocytes. Also ECM components and ERK activation increased >2-fold and 1.5-fold, respectively in insulin resistant and hypertrophied adipocytes. Metformin caused reduction of activity of integrin/ERK pathway in Metformin treated insulin resistant and hypertrophied adipocytes compared to untreated group. Metformin also reduced collagen VI in both gene and protein expression level, MMP2 and MMP9 in gene expression, and also the expression of apoptosis and necrosis gene. Metformin with reduction of ECM component as collagen VI, MMP2 and MMP9, integrin/ERK pathway, necrosis markers as RIPK1, RIPK3 and MLKL, and apoptosis markers including DAP, DAPK1, DAPK3 and SIVA effects on fibrosis in insulin resistant and hypertrophied adipocytes in vitro. [ABSTRACT FROM AUTHOR]