Changes in the properties of membrane tethers in response to HP1α depletion in MCF7 cells

Author(s):  
Susav Pradhan ◽  
Martin A.K. Williams ◽  
Tracy K. Hale
Keyword(s):  
2018 ◽  
Vol 6 (10) ◽  
Author(s):  
Hosam Zaghloul ◽  
Doaa A. Shahin ◽  
Ibrahim El- Dosoky ◽  
Mahmoud E. El-awady ◽  
Fardous F. El-Senduny ◽  
...  

Antisense oligonucleotides (ASO) represent an attractive trend as specific targeting molecules but sustain poor cellular uptake meanwhile superparamagnetic iron oxide nanoparticles (SPIONs) offer stability of ASO and improved cellular uptake. In the present work we aimed to functionalize SPIONs with ASO targeting the mRNA of Cyclin B1 which represents a potential cancer target and to explore its anticancer activity. For that purpose, four different SPIONs-ASO conjugates, S-M (1–4), were designated depending on the sequence of ASO and constructed by crosslinking carboxylated SPIONs to amino labeled ASO. The impact of S-M (1–4) on the level of Cyclin B1, cell cycle, ROS and viability of the cells were assessed by flowcytometry. The results showed that S-M3 and S-M4 reduced the level of Cyclin B1 by 35 and 36%, respectively. As a consequence to downregulation of Cyclin B1, MCF7 cells were shown to be arrested at G2/M phase (60.7%). S-M (1–4) led to the induction of ROS formation in comparison to the untreated control cells. Furthermore, S-M (1–4) resulted in an increase in dead cells compared to the untreated cells and SPIONs-treated cells. In conclusion, targeting Cyclin B1 with ASO-coated SPIONs may represent a specific biocompatible anticancer strategy.


2002 ◽  
Vol 7 (2) ◽  
pp. 128-132
Author(s):  
Won-Chul Park ◽  
Joo-Young Son ◽  
Sook-Hyun Chung ◽  
Woon-Gun An
Keyword(s):  

Author(s):  
Chuan Chen ◽  
Ziyue Zhao ◽  
Qian Dong ◽  
XueHui Gao ◽  
Huibin Xu ◽  
...  

Background:: Xanthones are a class of heterocyclic natural products, which are promising sources of anticancer leads. Phomoxanthone B(PXB)and Phomoxanthone A(PXA)are xanthone dimers. PXA is well studied as an anti-cancer agent, but PXB is not. In our study, PXB was isolated from the endophytic fungus Phomopsis sp. By254. Objective:: The purpose of this study was to identify the underlying anti-tumor mechanisms of PXB in breast cancer MCF7 cell line. Methods:: Apoptosis, cell cycle, proliferation, invasion and migration assays were used to assess the antitumor activity of PXB. RNA sequencing was used to analyze the effect of PXB treatment on gene expression in MCF7 cells. Results:: PXB showed cytotoxicity toward a variety of tumor cells, especially MCF7 cells. PXB inhibited the migration and invasion, arrested cell cycle at G2/M phase and induced apoptosis associated with caspase-3 activation in MCF7 cells. The detailed transcriptome analysis revealed that PXB affected several pathways related to tumorigenesis, metabolisms-, and oxidative phosphorylation in MCF7 cells. KEGG transcriptome analysis revealed that PXB upregulated pro-survival signal pathways such as MAPK, PI3K-AKT and STAT3 pathways. We found that PXB also significantly upregulated the expression of IL24, DDIT3 and XAF1, which may contribute to PXB-induced apoptosis. We further found that PXB may downregulate oxidative phosphorylation by decreasing the expression of electron transport chain genes, especially MT-ND1, which is a potential unfavorable prognostic marker for ER-positive breast cancer. Conclusion:: PXB exerts strong cytotoxicity against human tumor cells and has a potential for ER-positive breast cancer treatment.


Author(s):  
Abdel Qader Al Bawab ◽  
Malek Zihlif ◽  
Yazan Jarrar ◽  
Ahmad Saleh

Background: Hypoxia (deprived oxygen in tissues) may induce molecular and genetic changes in cancer cells. Objective: Investigating the genetic changes of glucose metabolism in breast cancer cell line (MCF7) after exposure to continuous hypoxia (10 and 20 cycles exposure of 72 hours continuously on a weekly basis). Method: Gene expression of MCF7 cells was evaluated using real-time polymerase chain reaction- array method. Furthermore, cell migration and wound healing assays were also applied. Results: It was found that 10 episodes of continuous hypoxia activated Warburg effect in MCF7 cells via the significant up-regulation of genes involved in glycolysis (ANOVA, p value < 0.05). The molecular changes were associated with the ability of MCF7 cells to divide and migrate. Interestingly, after 20 episodes of continuous hypoxia, the expression glycolysis mediated genes has dropped significantly (from 30 to 9 folds). This could be attributed to the adaptive ability of cancer cells. Conclusion: It is concluded that 10 hypoxic episodes increased the survival rate and the aggressiveness of MCF7 cells and induced Warburg effect by up-regulation of the glycolysis mediating genes expression.


2019 ◽  
Vol 9 (1) ◽  
pp. 76-85 ◽  
Author(s):  
R. Nithya ◽  
K. Siram ◽  
R. Hariprasad ◽  
H. Rahman

Background: Paclitaxel (PTX) is a potent anticancer drug which is highly effective against several cancers. Solid lipid nanoparticles (SLNs) loaded with anticancer drugs can enhance its toxicity against tumor cells at low concentrations. Objective: To develop and characterize SLNs of PTX (PSLN) to enhance its toxicity against cancerous cells. Method: The solubility of PTX was screened in various lipids. Solid lipid nanoparticles of PTX (PSLN) were developed by hot homogenization method using Cutina HR and Gelucire 44/14 as lipid carriers and Solutol HS 15 as a surfactant. PSLNs were characterized for size, morphology, zeta potential, entrapment efficiency, physical state of the drug and in vitro release profile in 7.4 pH phosphate buffer saline (PBS). The ability of PTX to enhance toxicity towards cancerous cells was tested by performing cytoxicity assay in MCF7 cell line. Results: Solubility studies of PTX in lipids indicated better solubility when Cutina HR and Gelucire 44/14 were used. PSLNs were found to possess a neutral zeta potential with a size range of 155.4 ± 10.7 nm to 641.9 ± 4.2 nm. In vitro release studies showed a sustained release profile for PSLN over a period of 48 hours. SLNs loaded with PTX were found to be more toxic in killing MCF7 cells at a lower concentration than the free PTX.


2018 ◽  
Vol 10 (1) ◽  
pp. 102
Author(s):  
Robby Hertanto ◽  
Wilson Bastian ◽  
Paramita . ◽  
Melva Louisa

Objective: The aim of the present study was to determine whether curcumin (CM) can prevent drug sensitivity of breast cancer (BC) cells when E andβ-E2 are administered together and whether the underlying mechanism involves modulation of drug efflux transporters.Methods: MCF7 BC cells were treated with the vehicle only, E+β-E2, or E+β-E2+CM repeatedly for 8 weeks. Afterward, the cells were harvested,counted, and isolated for total RNA extraction. Total RNA was then processed into cDNA and further processed for the determination of mRNAexpression patterns of drug efflux transporters (P-glycoprotein, BCRP, and MRP1).Results: Decreased sensitivity of BC cells was shown by the increased cell viability of MCF7 cells after 8 weeks. This condition was accompanied withincreased mRNA expression of P-glycoprotein, BCRP, and MRP1 in cells treated with E+β-E2, as compared with the vehicle only. CM, administered incombination with E+β-E2, resulted in decreased cell viability versus E and β-E2 and also decreased in mRNA expression of P-glycoprotein, BCRP, andMRP1.Conclusion: CM partially reversed the sensitivity loss of BC cells to E in the presence of β-E2 by modulating drug efflux transporters.


Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 558
Author(s):  
Jin Kyung Seok ◽  
Eun-Hee Hong ◽  
Gabsik Yang ◽  
Hye Eun Lee ◽  
Sin-Eun Kim ◽  
...  

Oxidized phospholipids are well known to play physiological and pathological roles in regulating cellular homeostasis and disease progression. However, their role in cancer metastasis has not been entirely understood. In this study, effects of oxidized phosphatidylcholines such as 1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphocholine (POVPC) on epithelial-mesenchymal transition (EMT) and autophagy were determined in cancer cells by immunoblotting and confocal analysis. Metastasis was analyzed by a scratch wound assay and a transwell migration/invasion assay. The concentrations of POVPC and 1-palmitoyl-2-glutaroyl-sn-glycero-phosphocholine (PGPC) in tumor tissues obtained from patients were measured by LC-MS/MS analysis. POVPC induced EMT, resulting in increase of migration and invasion of human hepatocellular carcinoma cells (HepG2) and human breast cancer cells (MCF7). POVPC induced autophagic flux through AMPK-mTOR pathway. Pharmacological inhibition or siRNA knockdown of autophagy decreased migration and invasion of POVPC-treated HepG2 and MCF7 cells. POVPC and PGPC levels were greatly increased at stage II of patient-derived intrahepatic cholangiocarcinoma tissues. PGPC levels were higher in malignant breast tumor tissues than in adjacent nontumor tissues. The results show that oxidized phosphatidylcholines increase metastatic potential of cancer cells by promoting EMT, mediated through autophagy. These suggest the positive regulatory role of oxidized phospholipids accumulated in tumor microenvironment in the regulation of tumorigenesis and metastasis.


2021 ◽  
Vol 22 (13) ◽  
pp. 6768
Author(s):  
Afsaneh Malekzadeh Shafaroudi ◽  
Ali Sharifi-Zarchi ◽  
Saeid Rahmani ◽  
Nahid Nafissi ◽  
Seyed Javad Mowla ◽  
...  

miR-29b2 and miR-29c play a suppressive role in breast cancer progression. C1orf132 (also named MIR29B2CHG) is the host gene for generating both microRNAs. However, the region also expresses longer transcripts with unknown functions. We employed bioinformatics and experimental approaches to decipher C1orf132 expression and function in breast cancer tissues. We also used the CRISPR/Cas9 technique to excise a predicted C1orf132 distal promoter and followed the behavior of the edited cells by real-time PCR, flow cytometry, migration assay, and RNA-seq techniques. We observed that C1orf132 long transcript is significantly downregulated in triple-negative breast cancer. We also identified a promoter for the longer transcripts of C1orf132 whose functionality was demonstrated by transfecting MCF7 cells with a C1orf132 promoter-GFP construct. Knocking-out the promoter by means of CRISPR/Cas9 revealed no alterations in the expression of the neighboring genes CD46 and CD34, while the expression of miR-29c was reduced by half. Furthermore, the promoter knockout elevated the migration ability of the edited cells. RNA sequencing revealed many up- and downregulated genes involved in various cellular pathways, including epithelial to mesenchymal transition and mammary gland development pathways. Altogether, we are reporting here the existence of an additional/distal promoter with an enhancer effect on miR-29 generation and an inhibitory effect on cell migration.


2021 ◽  
Vol 22 (4) ◽  
pp. 2056
Author(s):  
Kitti Andreidesz ◽  
Balazs Koszegi ◽  
Dominika Kovacs ◽  
Viola Bagone Vantus ◽  
Ferenc Gallyas ◽  
...  

Triple-negative breast cancer (TNBC) has a poor prognosis as the therapy has several limitations, most importantly, treatment resistance. In this study we examined the different responses of triple-negative breast cancer line MDA-MB-231 and hormone receptor-positive breast cancer line MCF7 to a combined treatment including olaparib, a poly-(ADP ribose) polymerase (PARP) inhibitor, oxaliplatin, a third-generation platinum compound and LY294002, an Akt pathway inhibitor. We applied the drugs in a single, therapeutically relevant concentration individually and in all possible combinations, and we assessed the viability, type of cell death, reactive oxygen species production, cell-cycle phases, colony formation and invasive growth. In agreement with the literature, the MDA-MB-231 cells were more treatment resistant than the MCF7 cells. However, and in contrast with the findings of others, we detected no synergistic effect between olaparib and oxaliplatin, and we found that the Akt pathway inhibitor augmented the cytostatic properties of the platinum compound and/or prevented the cytoprotective effects of PARP inhibition. Our results suggest that, at therapeutically relevant concentrations, the cytotoxicity of the platinum compound dominated over that of the PARP inhibitor and the PI3K inhibitor, even though a regression-based model could have indicated an overall synergy at lower and/or higher concentrations.


Sign in / Sign up

Export Citation Format

Share Document