Podcasts about mcf7

BUFFALO, NY- June 17, 2024 – A new research paper was published on the cover of Aging (listed by MEDLINE/PubMed as "Aging (Albany NY)" and "Aging-US" by Web of Science) Volume 16, Issue 11, entitled, “Mitophagy and cancer: role of BNIP3/BNIP3L as energetic drivers of stemness features, ATP production, proliferation, and cell migration.” Mitophagy is a selective form of autophagy which permits the removal of dysfunctional or excess mitochondria. This occurs as an adaptative response to physiological stressors, such as hypoxia, nutrient deprivation, or DNA damage. Mitophagy is promoted by specific mitochondrial outer membrane receptors, among which are BNIP3 and BNIP3L. The role of mitophagy in cancer is being widely studied, and more specifically in the maintenance of cancer stem cell (CSC) properties, such as self-renewal. Given that CSCs are responsible for treatment failure and metastatic capacity, targeting mitophagy could be an interesting approach for CSC elimination. In this new study, researchers Marta Mauro-Lizcano, Federica Sotgia, and Michael P. Lisanti from the University of Salford describe a new model system to enrich sub-populations of cancer cells with high basal levels of mitophagy, based on the functional transcriptional activity of BNIP3 and BNIP3L. “Briefly, we employed a BNIP3(L)-promoter-eGFP-reporter system to isolate cancer cells with high BNIP3/BNIP3L transcriptional activity by flow cytometry (FACS).” The model was validated by using complementary lysosomal and mitophagy-specific probes, as well as the mitochondrially-targeted red fluorescent protein (RFP), namely mt-Keima. High BNIP3/BNIP3L transcriptional activity was accompanied by increases in i) BNIP3/BNIP3L protein levels, ii) lysosomal mass, and iii) basal mitophagy activity. Furthermore, cancer cells with increased BNIP3/BNIP3L transcriptional activity exhibited CSC features, such as greater mammosphere-forming ability and high CD44 levels. “To further explore the model, we also analysed other stemness characteristics in MCF7 and MDA-MB-231 breast cancer cell lines, directly demonstrating that BNIP3(L)-high cells were more metabolically active, proliferative, migratory, and drug-resistant, with elevated anti-oxidant capacity. Therefore, high levels of basal mitophagy appear to enhance CSC features.” DOI - https://doi.org/10.18632/aging.205939 Corresponding authors - Federica Sotgia - fsotgia@gmail.com, and Michael P. Lisanti - michaelp.lisanti@gmail.com Video short - https://www.youtube.com/watch?v=n872jCkc-q8 Sign up for free Altmetric alerts about this article - https://aging.altmetric.com/details/email_updates?id=10.18632%2Faging.205939 Subscribe for free publication alerts from Aging - https://www.aging-us.com/subscribe-to-toc-alerts About Aging-US Aging publishes research papers in all fields of aging research, including but not limited to aging processes (from yeast to mammals), cellular senescence, age-related diseases (such as cancer and Alzheimer's disease) and their prevention and treatment, anti-aging strategies and drug development, and, importantly, the role of signal transduction pathways in aging (such as mTOR) and potential approaches to modulate these signaling pathways to extend lifespan. The journal aims to promote 1) treatment of age-related diseases by slowing down aging, 2) validation of anti-aging drugs by treating age-related diseases, and 3) prevention of cancer by inhibiting aging. (Cancer and COVID-19 are age-related diseases.) Please visit our website at https://www.Aging-US.com​​ and connect with us: Facebook - https://www.facebook.com/AgingUS/ X - https://twitter.com/AgingJrnl Instagram - https://www.instagram.com/agingjrnl/ YouTube - https://www.youtube.com/@AgingJournal LinkedIn - https://www.linkedin.com/company/aging/ Pinterest - https://www.pinterest.com/AgingUS/ Spotify - https://open.spotify.com/show/1X4HQQgegjReaf6Mozn6Mc MEDIA@IMPACTJOURNALS.COM

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.07.20.549847v1?rss=1 Authors: Aarts, M. T., Wagner, M., van der Wal, T., van Boxtel, A. L., van Amerongen, R. Abstract: Progesterone receptor (PR) signaling is required for mammary gland development and homeostasis. A major bottleneck in studying PR signaling is the lack of sensitive assays to measure and visualize PR pathway activity both quantitatively and spatially. Here, we develop new tools to study PR signaling in human breast epithelial cells. First, we generate optimized Progesterone Responsive Element (PRE)-luciferase constructs and demonstrate that these new reporters are a powerful tool to quantify PR signaling activity across a wide range of progesterone concentrations in two luminal breast cancer cell lines, MCF7 and T47D. We also describe a fluorescent lentiviral PRE-GFP reporter as a novel tool to visualize PR signaling at the single-cell level. Our reporter constructs are sensitive to physiological levels of progesterone. Second, we show that low background signaling, and high levels of PR expression are a prerequisite for robustly measuring PR signaling. Increasing PR expression by transient transfection, stable overexpression in MCF7 or clonal selection in T47D, drastically improves both the dynamic range of luciferase reporter assays, and the induction of endogenous PR target genes as measured by qRT-PCR. We find that the PR signaling response differs per cell line, target gene and hormone concentration used. Taken together, our tools allow a more rationally designed approach for measuring PR signaling in breast epithelial cells. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.07.06.547926v1?rss=1 Authors: Pauwels, J., Van de Steene, T., Van de Velde, J., Eyckerman, S., Gevaert, K. Abstract: Extracellular vesicles (EVs), membrane-delimited nanovesicles that are secreted by cells into the extracellular environment, are gaining substantial interest due to their involvement in cellular homeostasis and their contribution to disease pathology. The latter in particular has led to an exponential increase in interest in EVs as they are considered to be circulating packages containing potential biomarkers and are also a possible biological means to deliver drugs in a cell-specific manner. However, several challenges hamper straightforward analysis of EVs as they are generally low abundant and reside in complex biological matrices. These matrices typically contain protein concentrations that vastly exceed those of the EV proteome and contain particles in the same size and density range (e.g. protein aggregates and apolipoprotein particles). Therefore, extensive EV isolation and purification protocols are imperative and many have been developed, including (density) ultracentrifugation, size-exclusion and precipitation methods. Here, we describe an approach based on 300 kDa MWCO filtration, which allows processing of multiple samples in parallel within a reasonable timeframe and at moderate cost. We demonstrate that our strategy is capable of quantitatively retaining EV particles on filters, whilst allowing extensive washing with relatively high percentages of the mild detergent TWEEN-20. In addition, we provide evidence that the retained EVs can be recuperated from the filter for qualitative studies or can be directly lysed on the filter for the recovery of the EV protein cargo for proteome analysis. Applying this strategy on MCF7 conditioned medium using different percentages of serum, we observed dramatic changes in the EV proteome. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.07.06.547935v1?rss=1 Authors: Kalampouka, I., Mould, R. R., Botchway, S. W., Mackenzie, A., Nunn, A. V., Thomas, E. L., Bell, J. D. Abstract: The application of near infrared (NIR)-light to living systems has been suggested as a potential method to enhance tissue repair, decrease inflammation, and possibly mitigate cancer therapy-associated side effects. In this study, we examined the effect of exposing three cell lines: breast cancer (MCF7), non-cancer breast cells (MCF10A), and lung fibroblasts (IMR-90), to 734 nm NIR-light for 20 minutes per day for six days, and measuring changes in cellular senescence. Positive senescent populations were induced using doxorubicin. Flow cytometry was used to assess relative levels of senescence together with mitochondria-related variables. Exposure to NIR-light significantly increased the level of senescence in MCF7 cells (13.5%; P less than 0.01), with no observable effects on MCF10A or IMR-90 cell lines. NIR-induced senescence was associated with significant changes in mitochondria homeostasis, including raised ROS level (36.0%; P less than 0.05) and mitochondrial membrane potential (14.9%; P less than 0.05), with no changes in mitochondrial Ca2+. These results suggest that NIR-light exposure can significantly arrest the proliferation of breast cancer cells via inducing senescence, while leaving non-cancerous cell lines unaffected. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.03.31.534207v1?rss=1 Authors: van Veen, S., Kourti, A., Ausloos, E., Van Asselberghs, J., Van den Haute, C., Baekelandt, V., Eggermont, J., Vangheluwe, P. Abstract: Polyamine homeostasis is disturbed in several human diseases, including cancer, which is hallmarked by increased intracellular polyamine levels and an upregulated polyamine transport system (PTS). So far, the polyamine transporters contributing to the elevated levels of polyamines in cancer cells have not yet been described, despite the fact that polyamine transport inhibitors are considered for cancer therapy. Here, we tested whether upregulation of candidate polyamine transporters of the P5B-transport ATPase family is responsible for the increased PTS in the well-studied breast cancer cell line MCF7 compared to the non-tumorigenic epithelial breast cell line MCF10A. We found that MCF7 cells present elevated expression of a previously uncharacterized P5B-ATPase ATP13A4, which is responsible for the elevated polyamine uptake activity. Furthermore, MCF7 cells are more sensitive to polyamine cytotoxicity, as demonstrated by cell viability, cell death and clonogenic assays. Importantly, overexpression of ATP13A4 WT in MCF10A cells induces a MCF7 polyamine phenotype, with significantly higher uptake of BODIPY-labelled polyamines and increased sensitivity to polyamine toxicity. In conclusion, we establish ATP13A4 as a new polyamine transporter in the human PTS and show that ATP13A4 may play a major role in the increased polyamine uptake of breast cancer cells. ATP13A4 therefore emerges as a candidate therapeutic target for anticancer drugs that block the PTS. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.01.22.525054v1?rss=1 Authors: Kliszczak, M., Moralli, D., Jankowska, J., Bryjka, P., Subha, L., Goncalves, T., Hester, S., Fischer, R., Clynes, D., Green, C. M. Abstract: Hereditary fibrosing poikiloderma (HFP) is a rare human dominant negative disorder caused by mutations in the FAM111B gene that encodes a nuclear trypsin-like serine protease. HFP patients present with symptoms including skin abnormalities, tendon contractures, myopathy and lung fibrosis. We characterised the cellular roles of human FAM111B using U2OS and MCF7 cell lines and report here that the protease interacts with components of the nuclear pore complex. Loss of FAM111B expression resulted in abnormal nuclear shape and reduced telomeric DNA content suggesting that FAM111B protease is required for normal telomere length; we show that this function is independent of telomerase or recombination driven telomere extension. Even though FAM111B-deficient cells were proficient in DNA repair, they showed hallmarks of genomic instability such as increased levels of micronuclei and ultra-fine DNA bridges. Interestingly, FAM111B variants, including mutations that cause HFP, showed more frequent localisation to the nuclear lamina suggesting that accumulation of mutant FAM111B at the nuclear periphery may drive the disease pathology. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

Volume 11, Issue 25 of @Oncotarget reported that the present study was aimed at evaluating the hypothesis that p53 governs the expression and activation of the INSR gene in breast cancer cells. The availability of MCF7 breast cancer-derived cell lines with specific disruption of either the insulin-like growth factor-1 receptor or INSR allowed us to address the impact of the IGF1R and INSR pathways on p53 expression. Wild-type p53 stimulated INSR promoter activity in control cells while disruption of endogenous IGF1R or INSR led to inhibition of promoter activity by p53. Mutant p53 strongly stimulated INSR promoter. Furthermore, p53 directly binds to the INSR promoter in cells with a disrupted IGF1R. Dr. Haim Werner from Tel Aviv University said, "The insulin/insulin-like growth factors (IGFs) create a hormonal network responsible for the regulation of important physiological events throughout life." The classical view that emerged following the cloning and characterization of the INSR and IGF1R genes in the mid-1980s postulated that activation of INSR by insulin leads, predominantly, to metabolic activities. One of the cardinal questions still in need of a biologically plausible rationalization is why the INSR and IGF1R, even though they share the majority of their downstream cytoplasmic targets and signaling pathways, are yet responsible for mediating distinct physiological and pathological activities. Given the emerging evidence of proliferative and potentially anti-apoptotic actions of INSR, the authors investigated in the present paper the regulation of the INSR gene promoter by wild-type and mutant p53 in breast cancer cells. Using cells with specific disruption of the INSR or IGF1R, the authors also assessed the effect of each one of these signaling pathways on p53 expression and activity. The data indicate that: activation of p53 is negatively regulated by IGF1R, as indicated by the augmented phosphorylation of p53 in IGF1R-KD cells; p53 directly binds to the INSR promoter region in cells with a disrupted IGF1R; wild-type p53 represses INSR promoter activity in IGF1R-KD and INSR-KD cells while enhancing promoter activity in control cells; mutant p53 stimulates INSR promoter activity in breast cancer cells. The Werner Research Team concluded in their Oncotarget Research Paper, "we have presented evidence that the INSR gene constitutes a downstream target for p53 action. Whereas wild-type p53 stimulated INSR promoter activity in control MCF7 cells, disruption of endogenous IGF1R or INSR led to inhibition of promoter activity by wild-type p53. Mutant, oncogenic versions of p53, for the most part, strongly stimulated INSR promoter. In addition, p53 exhibits direct binding to the INSR promoter region in cells with a disrupted IGF1R. Taken together, data presented here identifies complex functional and physical interactions between p53 and the INSR pathway. The clinical implications of this interplay in breast cancer needs to be critically assessed." DOI - https://doi.org/10.18632/oncotarget.27645 Full text - https://www.oncotarget.com/article/27645/text/ Correspondence to - Haim Werner - hwerner@post.tau.ac.il Keywords - insulin, insulin-like growth factor-1 (IGF1), insulin receptor, IGF1 receptor, p53 About Oncotarget Oncotarget is a weekly, peer-reviewed, open access biomedical journal covering research on all aspects of oncology. To learn more about Oncotarget, please visit https://www.oncotarget.com or connect with: SoundCloud - https://soundcloud.com/oncotarget Facebook - https://www.facebook.com/Oncotarget/ Twitter - https://twitter.com/oncotarget LinkedIn - https://www.linkedin.com/company/oncotarget Pinterest - https://www.pinterest.com/oncotarget/ Reddit - https://www.reddit.com/user/Oncotarget/ Oncotarget is published by Impact Journals, LLC please visit http://www.ImpactJournals.com or connect with @ImpactJrnls Media Contact MEDIA@IMPACTJOURNALS.COM 18009220957x105

Major advances in understanding and treating breast cancer have been made in the last two decades, yet it remains a significant problem with breast cancer being the most commonly identified cancer and the leading cause of cancer death among women worldwide. For many years breast cancer research has mainly focused on genetically changed cancer cells. However, recently the importance of the stromal compartment surrounding cancer cells in facilitating tumor growth, invasion and metastasis has been widely recognized. Cumulating evidence suggests that in particular carcinoma-associated myofibroblasts play a key role within the tumor stroma and influence many aspects of carcinogenesis. Nevertheless, the cell type of origin as well as the precise mechanisms by which these cells develop has not been conclusively established and remains controversial. The role of human adipose tissue derived stem cells (hASCs) in this context has not been studied so far. hASCs are locally adjacent to epithelial breast cancer cells and might represent early response cells within the tumor stroma. Hence, the aim of this study was to investigate whether carcinoma-associated myofibroblasts may originate from hASCs. The present study revealed that a significant percentage of hASCs differentiate into myofibroblast-like cells expressing alpha smooth muscle actin (α-SMA) and tenascin-C when exposed to conditioned medium from the human epithelial breast cancer cell lines MDMAB231 and MCF7. This process is induced by transforming growth factor beta 1 (TGFβ1) secreted from breast cancer cells. It was shown that conditioned medium from MDMAB231 and MCF7 contains significant amounts of TGFβ1. It could further be demonstrated that the differentiation of hASCs towards myofibroblasts is dependent on TGFβ1 signaling via phosphorylation of Smad2 and Smad3 in hASCs. The induction of myofibroblasts can be abolished using a neutralizing antibody to TGFβ1 as well as by pretreatment of hASCs with SB431542, a selective inhibitor of the TGFβ1 activin receptor-like kinases 4, 5 and 7. Additionally, hASC-derived myofibroblasts exhibit functional properties of carcinoma-associated myofibroblasts such as the increased secretion of the tumor-promoting soluble factors SDF-1α and CCL5. Furthermore hASC-derived myofibroblasts as well as conditioned medium from these cells promote the in vitro invasion of MDAMB231 breast cancer cells. Moreover inhibition of the TGFβ1 signaling pathway in hASCs reduces the potential of these cells to enhance the invasion of breast cancer cells. Overall, the data of the present study suggest that human adipose tissue derived stem cells can differentiate into carcinoma-associated myofibroblast under the influence of TGFβ1 secreted from breast cancer cells in vitro. The differentiation of hASCs towards these tumor-promoting cells can be abolished by targeting the TGFβ1 signaling pathway. Hence, inhibition of the TGFβ1 signaling pathway may prove to be an interesting target for breast cancer therapies. In vivo studies on the cancer microenvironment under special consideration of the interactions between hASCs and cancer cells should be of interest for breast cancer research in the future.

Targeting the cytoskeleton (CSK) of cancer cells offers a valuable strategy in cancer therapy. Whereas drugs which address microtubule CSK such as vinca alkaloids or taxanes are well established in the clinic, compounds binding to the actin CSK are still far away from their therapeutical application. One reason might be the lacking knowledge on their mode of cytotoxicity and moreover their tumor specific mechanism of action. We used the myxobacterial compound Chondramide as a tool to first elucidate the mechanisms of cytotoxicity by actin targeting in different breast cancer cells, namely MCF7 and MDA-MB-231. Chondramide inhibits actin filament assembly and dynamics shown by a fluorescence-based analysis (FRAP) in whole cells and leads to apoptosis characterized by phosphatidylserine exposure, release of cytochrome C from mitochondria and finally activation of caspases (-9 and -3). Detailed analysis revealed, that Chondramide induces apoptosis by enhancing the occurrence of mitochondrial permeability transition (MPT). Known MPT-modulators were found to be affected by Chondramide: Hexokinase II (HkII) bound to the voltage dependent anion channel (VDAC) translocated from the outer mitochondrial membrane to the cytosol and the proapoptotic protein Bad was recruited to the mitochondria. Importantly, PKCε, a prosurvival serine/threonine kinase possessing an actin-binding site and known to regulate the HkII/VDAC interaction as well as Bad phosphoylation was identified as the link between actin CSK and apoptosis induction. PKCε which was found overexpressed in breast cancer cells accumulated in actin bundles induced by Chondramide and lost its activity. The second goal of our work was to inform on a potential tumor specific action of actin binding agents such as Chondramide. As the nontumor breast epithelial cell line MCF-10A in fact shows resistance to Chondramide induced apoptosis and notably express very low level of PKCε we claim that trapping PKCε via Chondramide induced actin hyperpolymerization displays tumor cell specificity. Our work provides a link between targeting the ubiquitously occurring actin CSK and selective inhibition of pro-tumorigenic PKCε, thus setting the stage for actin-stabilizing agents as innovative cancer drugs. This is moreover supported by the in vivo efficacy of Chondramide triggered by abrogation of PKCε signaling shown in a xenograft breast cancer model. For the actin targeting compound Doliculide we could show that Doliculide impairs the dynamics of the actin CSK similar to Chondramide. Moreover, it reduces the proliferation rate and migration of cancer cells and also leads to the induction of apoptosis, thus Doliculide is also an interesting lead structure for further preclinical investigations.

Background: Several secondary metabolites from herbal nutrient products act as weak estrogens (phytoestrogens), competing with endogenous estrogen for binding to the estrogen receptors and inhibiting steroid converting enzymes. However, it is still unclear whether these compounds elicit estrogen dependent transcription of genes at physiological concentrations. Methods: We compare the effects of physiological concentrations (100 nM) of the two phytoestrogens Enterolactone and Quercetin and the suspected phytoestrogen Curcumin on gene expression in the breast cancer cell line MCF7 with the effects elicited by 17-beta-estradiol (E2). Results: All three phytocompounds have weak effects on gene transcription; most of the E2 genes respond to the phytoestrogens in the same direction though to a much lesser extent and in the order Curcumin > Quercetin > Enterolactone. Gene regulation induced by these compounds was low for genes strongly induced by E2 and similar to the latter for genes only weakly regulated by the classic estrogen. Of interest with regard to the treatment of menopausal symptoms, the survival factor Birc5/survivin and the oncogene MYBL1 are strongly induced by E2 but only marginally by phytoestrogens. Conclusion: This approach demonstrates estrogenic effects of putative phytoestrogens at physiological concentrations and shows, for the first time, estrogenic effects of Curcumin. Copyright (C) 2010 S. Karger AG, Basel

Introduction: The HIV protease inhibitor nelfinavir is currently under investigation as a new anti-cancer drug. Several studies have shown that nelfinavir induces cell cycle arrest, endoplasmic reticulum stress, autophagy, and apoptosis in cancer cells. In the present article, the effect of nelfinavir on human breast cancer cells is examined and potential combination treatments are investigated. Methods: The effects of nelfinavir and tamoxifen on the human breast cancer cell lines MCF7, T47 D, MDA-MB-453, and MDA-MB-435 were tested by analysing their influence on cell viability (via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay), apoptosis (annexin binding, poly(ADP-ribose) polymerase cleavage), autophagy (autophagy marker light chain 3B expression), endoplasmic reticulum stress (binding protein and activating transcription factor 3 expression), and the occurrence of oxidative stress (intracellular glutathione level). Results: Nelfinavir induced apoptosis in all four breast cancer cell lines tested, although the extent of autophagy and endoplasmic reticulum stress varied among the cell lines. The concentration of nelfinavir needed for an efficient induction of apoptosis in breast cancer cells could be reduced from 15 mu g/ml to 6 mu g/ml when combined with tamoxifen. At a concentration of 6 mu g/ml, tamoxifen substantially enhanced the endoplasmic reticulum stress reaction in those cell lines that responded to nelfinavir with binding protein (BiP) upregulation (MCF7, T47D), and enhanced autophagy in cell lines that responded to nelfinavir treatment with autophagy marker light chain 3B upregulation (MDA-MB-453). Although tamoxifen has been described to be able to induce oxidative stress at concentrations similar to those applied in this study (6 mu g/ml), we observed that nelfinavir but not tamoxifen reduced the intracellular glutathione level of breast cancer cells within hours of application by up to 32%, suggesting the induction of oxidative stress was an early event and an additional cause of the apoptosis induced by nelfinavir. Conclusions: The results demonstrate that nelfinavir may be an effective drug against breast cancer and could be combined with tamoxifen to enhance its efficacy against breast cancer cells. Moreover, the cytotoxic effect of a tamoxifen and nelfinavir combination was independent of the oestrogen receptor status of the analysed breast cancer cells, suggesting a potential benefit of a combination of these two drugs even in patients with no hormone-responsive tumours. We therefore recommend that clinical studies on nelfinavir with breast cancer patients should include this drug combination to analyse the therapeutic efficacy as well as the safety and tolerability of this potential treatment option.