scholarly journals Platinum-Based Drugs Differentially Affect the Ultrastructure of Breast Cancer Cell Types

2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Shadia Al-Bahlani ◽  
Buthaina Al-Dhahli ◽  
Kawther Al-Adawi ◽  
Abdurahman Al-Nabhani ◽  
Mohamed Al-Kindi

Breast cancer (BC) is the most common cause of cancer-related death worldwide. Although platinum-based drugs (PBDs) are effective anticancer agents, responsive patients eventually become resistant. While resistance of some cancers to PBDs has been explored, the cellular responses of BC cells are not studied yet. Therefore, we aim to assess the differential effects of PBDs on BC ultrastructure. Three representative cells were treated with different concentrations and timing of Cisplatin, Carboplatin, and Oxaliplatin. Changes on cell surface and ultrastructure were detected by scanning (SEM) and transmission electron microscope (TEM). In SEM, control cells were semiflattened containing microvilli with extending lamellipodia while treated ones were round with irregular surface and several pores, indicating drug entry. Prolonged treatment resembled distinct apoptotic features such as shrinkage, membrane blebs, and narrowing of lamellipodia with blunt microvilli. TEM detected PBDs’ deposits that scattered among cellular organelles inducing structural distortion, lumen swelling, chromatin condensation, and nuclear fragmentation. Deposits were attracted to fat droplets, explained by drug hydrophobic properties, while later they were located close to cell membrane, suggesting drug efflux. Phagosomes with destructed organelles and deposits were detected as defending mechanism. Understanding BC cells response to PBDs might provide new insight for an effective treatment.

2012 ◽  
Vol 18 (3) ◽  
pp. 462-469 ◽  
Author(s):  
Rebecca S.Y. Wong ◽  
Ammu K. Radhakrishnan ◽  
Tengku Azmi Tengku Ibrahim ◽  
Soon-Keng Cheong

AbstractTocotrienols are isomers of the vitamin E family, which have been reported to exert cytotoxic effects in various cancer cells. Although there have been some reports on the effects of tocotrienols in leukemic cells, ultrastructural evidence of tocotrienol-induced apoptotic cell death in leukemic cells is lacking. The present study investigated the effects of three isomers of tocotrienols (alpha, delta, and gamma) on a human T lymphoblastic leukemic cell line (CEM-SS). Cell viability assays showed that all three isomers had cytotoxic effects (p < 0.05) on CEM-SS cells with delta-tocotrienol being the most potent. Transmission electron microscopy showed that the cytotoxic effects by delta- and gamma-tocotrienols were through the induction of an apoptotic pathway as demonstrated by the classical ultrastructural apoptotic changes characterized by peripheral nuclear chromatin condensation and nuclear fragmentation. These findings were confirmed biochemically by the demonstration of phosphatidylserine externalization via flow cytometry analysis. This is the first study showing classical ultrastructural apoptotic changes induced by delta- and gamma-tocotrienols in human T lymphoblastic leukemic cells.


2019 ◽  
Vol 67 (3) ◽  
pp. 127-139
Author(s):  
Ahmed Al-Emam ◽  
Mubarak Al-Shraim ◽  
Refaat Ali Eid ◽  
Abdul-Moneim Jamil ◽  
Mahmoud Fawzy Moustafa ◽  
...  

In this study, the effect of Euphorbia peplus aqueous extract on human breast cancer cell line MCF7 was examined. The short and long term cytotoxicity were evaluated using sulphorhodamine B and clonogenic assays respectively. Scanning and transmission electron microscopy were employed to examine Euphorbia peplus-induced ultrastructural changes in MCF7 cells. The sulphorhodamine B assay revealed that Euphorbia peplus inhibits the growth of MCF7 with an IC50 of 30.32 μg/ml. The clonogenic assay proved that Euphorbia peplus' growth inhibitory effect is long lasting. The ultrastructural examination demonstrated that Euphorbia peplus extract induces MCF7 cell death. Scanning electron microscopy showed apoptotic blebbing. Transmission electron microscopy displayed cellular shrinkage, the formulation of apoptotic bodies, mitochondrial changes, nuclear shrinkage, chromatin condensation, autophagic vacuoles, and necrotic changes. In summary, Euphorbia peplus has displayed growth inhibitory activity against MCF7 cells and induces cell death predominantly via apoptosis and could be exploited as a breast cancer treatment after further evaluation.


Author(s):  
Upasana Yadav ◽  
Yogesh Vanjari ◽  
Kritika Laxmikeshav ◽  
Ramya Tokala ◽  
Praveen Kumar Niggula ◽  
...  

Objective: To synthesize a series of phenanthrene-thiazolidinedione hybrids and explore their cytotoxic potential against human cancer cell lines of A-549 (lung cancer), HCT-116 and HT-29 (colon cancer), MDA MB-231 (triple negative breast cancer), BT-474 (breast cancer) and (mouse melanoma) B16F10 cells. Methods: A new series of phenanthrene-thiazolidinedione hybrids was synthesized via Knoevenagel condensation of phenanthrene-9-carbaldehyde and N-alkylated thiazolidinediones. The cytotoxicity (IC50) of the synthesized compounds was determined by MTT assay. Apoptotic assays like (AO/EB) and DAPI staining, cell cycle analysis, JC-1 staining and Annexin V binding assay studies were performed for the most active compound (Z)-3-(4-bromobenzyl)-5-((2,3,6,7- tetramethoxyphenanthren-9-yl)methylene)thiazolidine-2,4-dione (17b). Molecular docking, dynamics and evaluation of pharmacokinetic (ADME/T) properties were also carried out by using Schrödinger. Results and Discussion: From the series of tested compounds, 17b unveiled promising cytotoxic action with IC50 value of 0.985 ± 0.02 μM on HCT-116 human colon cancer cells. The treatment of HCT-116 cells with 17b demonstrated distinctive apoptotic morphology like shrinkage of cells, horseshoe shaped nuclei formation and chromatin condensation. Flow-cytometry analysis revealed the G0/G1 phase cell cycle arrest in a dose dependent fashion. The AO/EB, DAPI, DCFDA, Annexin-V and JC-1 staining studies were performed in order to determine the effect of compound on cell viability. Computational studies were performed by using Schrödinger to determine the stability of the ligand with the DNA. Conclusion: The current study provides an insight on developing a series of phenanthrene thiazolidinedione derivatives as potential DNA interactive agents which might aid in colon cancer therapy.


Author(s):  
Juan Mora-Galindo ◽  
Jorge Arauz-Contreras

The zinc iodide-osmium tetroxide (ZIO) technique is presently employed to study both, neural and non neural tissues. Precipitates depends on cell types and possibly cell metabol ism as well.Guinea pig cecal mucosa, already known to be composed of epithelium with cells at different maturation stages and lamina propria which i s formed by morphologically and functionally heterogeneous cell population, was studied to determine the pat tern of ZIO impregnation. For this, adult Guinea pg cecal mucosa was fixed with buffered 1.2 5% g 1 utara 1 dehyde before incubation with ZIO for 16 hours, a t 4°C in the dark. Further steps involved a quick sample dehydration in graded ethanols, embedding in Epon 812 and sectioning to observe the unstained material under a phase contrast light microscope (LM) and a transmission electron microscope (TEM).


Author(s):  
M. K. Lamvik

When observing small objects such as cellular organelles by scanning electron microscopy, it is often valuable to use the techniques of transmission electron microscopy. The common practice of mounting and coating for SEM may not always be necessary. These possibilities are illustrated using vertebrate skeletal muscle myofibrils.Micrographs for this study were made using a Hitachi HFS-2 scanning electron microscope, with photographic recording usually done at 60 seconds per frame. The instrument was operated at 25 kV, with a specimen chamber vacuum usually better than 10-7 torr. Myofibrils were obtained from rabbit back muscle using the method of Zak et al. To show the component filaments of this contractile organelle, the myofibrils were partially disrupted by agitation in a relaxing medium. A brief centrifugation was done to clear the solution of most of the undisrupted myofibrils before a drop was placed on the grid. Standard 3 mm transmission electron microscope grids covered with thin carbon films were used in this study.


Author(s):  
Anuradha Thakur ◽  
Kamalpreet Kaur ◽  
Praveen Sharma ◽  
Ramit Singla ◽  
Sandeep Singh ◽  
...  

Background: Breast cancer (BC) is a leading cause of cancer-related deaths in women next to skin cancer. Estrogen receptors (ERs) play an important role in the progression of BC. Current anticancer agents have several drawbacks such as serious side effects and the emergence of resistance to chemotherapeutic drugs. As coumarins possess minimum side effect along with multi-drug reversal activity, it has a tremendous ability to regulate a diverse range of cellular pathways that can be explored for selective anticancer activity. Objectives: Synthesis and evaluation of new coumarin analogues for anti-proliferative activity on human breast cancer cell line MCF-7 along with exploration of binding interaction of the compounds for ER-α target protein by molecular docking. Method: In this study, the anti-proliferative activity of C-3 substituted coumarins analogues (1-17) has been evaluated against estrogen receptor-positive MCF-7 breast cancer cell lines. Molecular interactions and ADME study of the compounds were analyzed by using Schrodinger software. Results: Among the synthesized analogues 12 and 13 show good antiproliferative activity with IC50 values 1and 1.3 µM respectively. Molecular docking suggests a remarkable binding pose of all the seventeen compounds. Compounds 12 and 13 were found to exhibit dock score of -4.10 kcal/mol and -4.38 kcal/mol respectively. Conclusion: Compounds 12 and 13 showed the highest activity followed by 1 and 5. ADME properties of all compounds were in the acceptable range. The active compounds can be taken for lead optimization and mechanistic interventions for their in vivo study in the future.


Separations ◽  
2021 ◽  
Vol 8 (1) ◽  
pp. 8
Author(s):  
Kollur Shiva Prasad ◽  
Shashanka K Prasad ◽  
Ravindra Veerapur ◽  
Ghada Lamraoui ◽  
Ashwini Prasad ◽  
...  

Herein we report the synthesis of zinc oxide nanoparticles (ZnONPs) using Withania somnifera root extract (WSE) as an effective chelating agent. The microscopic techniques viz., X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and selected area electron diffraction (SAED) were employed to analyze the as-obtained ZnONPs. The crystalline planes observed from the XRD pattern agrees with the hexagonal wurtzite structure of the as-prepared ZnONPs. The aggregations and agglomerations observed in the SEM images indicated that the size of the as-prepared ZnONPs was between 30 and 43 nm. The interplanar distance between the lattice fringes observed in the HRTEM image was found to be 0.253 nm, which is in good agreement with the (100) plane obtained in the XRD pattern. Furthermore, the anti-breast cancer cytotoxic evaluation was carried out using the MCF-7 cell line, and the results showed significant cytotoxic effects in a dose-dependent manner.


Insects ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 640
Author(s):  
Natalia R. Moyetta ◽  
Fabián O. Ramos ◽  
Jimena Leyria ◽  
Lilián E. Canavoso ◽  
Leonardo L. Fruttero

Hemocytes, the cells present in the hemolymph of insects and other invertebrates, perform several physiological functions, including innate immunity. The current classification of hemocyte types is based mostly on morphological features; however, divergences have emerged among specialists in triatomines, the insect vectors of Chagas’ disease (Hemiptera: Reduviidae). Here, we have combined technical approaches in order to characterize the hemocytes from fifth instar nymphs of the triatomine Dipetalogaster maxima. Moreover, in this work we describe, for the first time, the ultrastructural features of D. maxima hemocytes. Using phase contrast microscopy of fresh preparations, five hemocyte populations were identified and further characterized by immunofluorescence, flow cytometry and transmission electron microscopy. The plasmatocytes and the granulocytes were the most abundant cell types, although prohemocytes, adipohemocytes and oenocytes were also found. This work sheds light on a controversial aspect of triatomine cell biology and physiology setting the basis for future in-depth studies directed to address hemocyte classification using non-microscopy-based markers.


2021 ◽  
pp. 131198
Author(s):  
Derya Osmaniye ◽  
Begum Nurpelin Saglik ◽  
Serkan Levent ◽  
Sinem Ilgın ◽  
Yusuf Ozkay ◽  
...  

2008 ◽  
Vol 28 (24) ◽  
pp. 7487-7503 ◽  
Author(s):  
Poornima Bhat-Nakshatri ◽  
Guohua Wang ◽  
Hitesh Appaiah ◽  
Nikhil Luktuke ◽  
Jason S. Carroll ◽  
...  

ABSTRACT Estrogen regulates several biological processes through estrogen receptor α (ERα) and ERβ. ERα-estrogen signaling is additionally controlled by extracellular signal activated kinases such as AKT. In this study, we analyzed the effect of AKT on genome-wide ERα binding in MCF-7 breast cancer cells. Parental and AKT-overexpressing cells displayed 4,349 and 4,359 ERα binding sites, respectively, with ∼60% overlap. In both cell types, ∼40% of estrogen-regulated genes associate with ERα binding sites; a similar percentage of estrogen-regulated genes are differentially expressed in two cell types. Based on pathway analysis, these differentially estrogen-regulated genes are linked to transforming growth factor β (TGF-β), NF-κB, and E2F pathways. Consistent with this, the two cell types responded differently to TGF-β treatment: parental cells, but not AKT-overexpressing cells, required estrogen to overcome growth inhibition. Combining the ERα DNA-binding pattern with gene expression data from primary tumors revealed specific effects of AKT on ERα binding and estrogen-regulated expression of genes that define prognostic subgroups and tamoxifen sensitivity of ERα-positive breast cancer. These results suggest a unique role of AKT in modulating estrogen signaling in ERα-positive breast cancers and highlights how extracellular signal activated kinases can change the landscape of transcription factor binding to the genome.


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