scholarly journals Complex Mitochondrial Dysfunction Induced by TPP+-Gentisic Acid and Mitochondrial Translation Inhibition by Doxycycline Evokes Synergistic Lethality in Breast Cancer Cells

Cells ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 407 ◽  
Author(s):  
Sebastián Fuentes-Retamal ◽  
Cristian Sandoval-Acuña ◽  
Liliana Peredo-Silva ◽  
Daniela Guzmán-Rivera ◽  
Mario Pavani ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Adaptive Response ◽  
Late Phase ◽  
Mitochondrial Translation ◽  
Chemical Chaperone ◽  
Protein Levels ◽  
Metabolic Remodeling ◽  
Mitochondrial Ribosome ◽  
Triphenylphosphonium Bromide

The mitochondrion has emerged as a promising therapeutic target for novel cancer treatments because of its essential role in tumorigenesis and resistance to chemotherapy. Previously, we described a natural compound, 10-((2,5-dihydroxybenzoyl)oxy)decyl) triphenylphosphonium bromide (GA-TPP+C10), with a hydroquinone scaffold that selectively targets the mitochondria of breast cancer (BC) cells by binding to the triphenylphosphonium group as a chemical chaperone; however, the mechanism of action remains unclear. In this work, we showed that GA-TPP+C10 causes time-dependent complex inhibition of the mitochondrial bioenergetics of BC cells, characterized by (1) an initial phase of mitochondrial uptake with an uncoupling effect of oxidative phosphorylation, as previously reported, (2) inhibition of Complex I-dependent respiration, and (3) a late phase of mitochondrial accumulation with inhibition of α-ketoglutarate dehydrogenase complex (αKGDHC) activity. These events led to cell cycle arrest in the G1 phase and cell death at 24 and 48 h of exposure, and the cells were rescued by the addition of the cell-penetrating metabolic intermediates l-aspartic acid β-methyl ester (mAsp) and dimethyl α-ketoglutarate (dm-KG). In addition, this unexpected blocking of mitochondrial function triggered metabolic remodeling toward glycolysis, AMPK activation, increased expression of proliferator-activated receptor gamma coactivator 1-alpha (pgc1α) and electron transport chain (ETC) component-related genes encoded by mitochondrial DNA and downregulation of the uncoupling proteins ucp3 and ucp4, suggesting an AMPK-dependent prosurvival adaptive response in cancer cells. Consistent with this finding, we showed that inhibition of mitochondrial translation with doxycycline, a broad-spectrum antibiotic that inhibits the 28 S subunit of the mitochondrial ribosome, in the presence of GA-TPP+C10 significantly reduces the mt-CO1 and VDAC protein levels and the FCCP-stimulated maximal electron flux and promotes selective and synergistic cytotoxic effects on BC cells at 24 h of treatment. Based on our results, we propose that this combined strategy based on blockage of the adaptive response induced by mitochondrial bioenergetic inhibition may have therapeutic relevance in BC.

Dihydrotestosterone induces chemo-resistance of triple-negative breast MDA-MB-231 cancer cells towards doxorubicin independent of ABCG2 and miR-328-3p

2021 ◽  
Vol 14 ◽  
Author(s):  
Bayan Al-Momany ◽  
Hana Hammad ◽  
Mamoun Ahram
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Drug Response ◽  
Therapeutic Strategy ◽  
Triple Negative ◽  
Model System ◽  
Cell Resistance ◽  
Protein Levels ◽  
Abcg2 Protein ◽  
Mcf 7

Background: Androgens potentially have an important role in the biology of breast cancer, particularly triple-negative breast cancer (TNBC). Androgen receptor (AR) may offer a novel therapeutic strategy including the use of microRNA (miRNA) molecules. We have previously shown that AR agonist, dihydrotestosterone (DHT), increases the expression of miR-328-3p in the TNBC MDA-MB-231 cells. One target of the latter miRNA is ATP-binding cassette subfamily G member 2 (ABCG2), which modulates the chemo-response of cancer cells by pumping out xenobiotics. Objective: Using MDA-MB-231 cells as a model system for TNBC, we hypothesized that DHT would induce cell sensitivity towards doxorubicin via increasing levels of miR-328-3p and, consequently, reducing ABCG2 levels. Methods: Chemo-response of cells towards doxorubicin, tamoxifen, and mitoxantrone was evaluated using cell viability MTT assay. Cells were transfected with both miR-328-3p mimic or antisense molecules. Real-time PCR was utilized to assess RNA levels and immunoblotting was performed to investigate levels of ABCG2 protein. PCR arrays were used to assess changes in the expression of drug response regulatory genes. Results: Contrary to our hypothesis, treating MDA-MB-231 cells with DHT, no effect towards tamoxifen or mitoxantrone and increased cell resistance towards doxorubicin were noted, concomitant with decreased expression of ABCG2. This under-expression of ABCG2 was also found in MCF-7 and MDA-MB-453 cells treated with DHT. Although miR-328-3p decreased ABCG2 mRNA and protein levels, the miRNA did not alter the chemo-response of cells towards doxorubicin and did not affect DHT-induced chemo-resistance. AR activation slightly decreased the expression of 5 genes, including insulin-like growth factor 1 receptor, that may explain the mechanism of DHT-induced chemo-resistance of cells. Conclusion: DHT regulates chemo-response via a mechanism independent of ABCG2 and miR-328-3p.

VITAMIN D DERIVATIVES IN COMBINATION WITH 9-cis RETINOIC ACID PROMOTE ACTIVE CELL DEATH IN BREAST CANCER CELLS

1995 ◽  
Vol 14 (3) ◽  
pp. 391-394 ◽  
Author(s):  
S Y James ◽  
A G Mackay ◽  
K W Colston
Keyword(s):  
Breast Cancer ◽  
Vitamin D ◽  
Retinoic Acid ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
P53 Protein ◽  
Protein A ◽  
Therapeutic Implications ◽  
Protein Levels ◽  
Mcf 7

ABSTRACT The effects of the novel vitamin D analogue, EB1089 alone, or in combination with the retinoid, 9-cis retinoic acid (9-cis RA) on indices of apoptosis in MCF-7 breast cancer cells have been examined. EB1089 was capable of reducing bcl-2 protein, a suppressor of apoptosis, and increasing p53 protein levels in MCF-7 cell cultures following 96h treatment. In the presence of 9-cis RA, EB1089 acted to further enhance the down-regulation and up-regulation of bcl-2 and p53 respectively. Furthermore, EB1089 induces DNA fragmentation in MCF-7 cells, a key feature of apoptosis, alone and in combination with 9-cis RA in situ. The observation that EB1089 and 9-cis RA act in a cooperative manner to enhance induction of apoptosis in these cells may have therapeutic implications.

scholarly journals Multistability and consequent phenotypic plasticity in AMPK-Akt double negative feedback loop in cancer cells

2020 ◽  
Author(s):  
Adithya Chedere ◽  
Kishore Hari ◽  
Saurav Kumar ◽  
Annapoorni Rangarajan ◽  
Mohit Kumar Jolly
Keyword(s):  
Breast Cancer ◽  
Phenotypic Plasticity ◽  
Cancer Cells ◽  
Cell Population ◽  
Negative Feedback ◽  
Feedback Loop ◽  
Phenotypic Switching ◽  
Negative Feedback Loop ◽  
Double Negative ◽  
Protein Levels

AbstractAdaptation and survival of cancer cells to various stress and growth factor conditions is crucial for successful metastasis. A double-negative feedback loop between two serine/threonine kinases AMPK and Akt can regulate the adaptation of breast cancer cells to matrix-deprivation stress. This feedback loop can generate majorly two phenotypes or cell states: matrix detachment-triggered pAMPKhigh/ pAktlow state, and matrix (re)attachment-triggered pAkthigh/ pAMPKlow state. However, whether these two cell states can exhibit phenotypic plasticity and heterogeneity in a given cell population, i.e., whether they can co-exist and undergo spontaneous switching to generate the other subpopulation, remains unclear. Here, we develop a mechanism-based mathematical model that captures the set of experimentally reported interactions among AMPK and Akt. Our simulations suggest that the AMPK-Akt feedback loop can give rise to two co-existing phenotypes (pAkthigh/ pAMPKlow and pAMPKhigh/pAktlow) in specific parameter regimes. Next, to test the model predictions, we segregated these two subpopulations in MDA-MB-231 cells and observed that each of them was capable of switching to another in adherent conditions. Finally, the predicted trends are supported by clinical data analysis of TCGA breast cancer and pan-cancer cohorts that revealed negatively correlated pAMPK and pAkt protein levels. Overall, our integrated computational-experimental approach unravels that AMPK-Akt feedback loop can generate multistability and drive phenotypic switching and heterogeneity in a cancer cell population.

Luteolin-Loading Her-2 Nanospheres Enhances Targeting and Therapeutic Effects of Breast Cancer

2021 ◽  
Vol 17 (8) ◽  
pp. 1545-1553
Author(s):  
Chuanguang Xiao ◽  
Xiaohong Wang ◽  
Jiacheng Shen ◽  
Yanjie Xia ◽  
Shusheng Qiu ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Water Solubility ◽  
Ultrasonic Method ◽  
Mrna Level ◽  
Therapeutic Effects ◽  
Treatment Benefit ◽  
Protein Levels ◽  
Her 2

Despite the broad anticancer activity, whereas the clinical application of luteolin is hindered by unsatisfactory water solubility and non-targeting. Herein, targeted inhibitory effects of luteolin-loading HER2 nanospheres (Her-2-NPs) were successfully prepared by thin film ultrasonic method. In comparison with the non-targeted nanospheres, Her-2 nanospheres could significantly boost the intake of luteolin in SK-BR-3 cells. The proliferation and apoptosis of breast cancer cells were detected by MTT testing and flow cytometry examination, respectively. Consequently, the expressions of FOXO1 mRNA level was detected using qPCR assay and protein level was detected using Westernblot. We discovered that Luteolin-loading Her-2 nanospheres could significantly hinder the proliferation of breast cancer cells, down-regulation their migration, and up-regulation FOXO1 expression at mRNA and protein levels, reveal a mechanism whereby luteolin interferes with breast cancer. Collectively, these results suggest Her-2-modified nanospheres increases the efficiency of luteolin uptake and thus improves the treatment benefit of breast cancer.

SIK2 Promotes Cisplatin Resistance Induced by Aerobic Glycolysis in Breast Cancer Cells through PI3K/AKT/mTOR Signaling Pathway

2020 ◽  
Author(s):  
Shoukai Zong ◽  
Wei Dai ◽  
Wencheng Fang ◽  
Xiangting Guo ◽  
Kai Wang
Keyword(s):  
Breast Cancer ◽  
Western Blot ◽  
Cancer Cells ◽  
Signaling Pathway ◽  
Breast Cancer Cells ◽  
Cisplatin Resistance ◽  
Aerobic Glycolysis ◽  
Mtor Signaling ◽  
Mtor Signaling Pathway ◽  
Protein Levels

Abstract Objective This study aimed to investigate the effect of SIK2 on cisplatin resistance induced by aerobic glycolysis in breast cancer cells and its potential mechanism. Methods qRT-PCR and Western blot were used to detect SIK2 mRNA and protein levels. Cisplatin (DDP) resistant cell lines of breast cancer cells were established, CCK-8 was used to measure and evaluate the viability, and Transwell was used to evaluate the cell invasion capability. Flow cytometry was adopted to evaluate the apoptosis rate. The glycolysis level was evaluated by measuring glucose consumption and lactic acid production. The protein levels of p-PI3K, p- protein kinase B (Akt) and p-mTOR were determined by western blot. Results SIK2 is highly expressed in breast cancer tissues and cells compared with adjacent tissues and normal human breast epithelial cells, and has higher diagnostic value for breast cancer. Silencing SIK2 expression can inhibit proliferation and invasion of breast cancer cells and induce their apoptosis. In addition, SIK2 knockdown inhibits glycolysis, reverses the resistance of drug-resistant cells to cisplatin, and inhibits PI3K/AKT/mTOR signaling pathway. When LY294002 is used to inhibit PI3K/AKT/mTOR signaling pathway, the effect of Sh-SIK2 on aerobic glycolysis of breast cancer cells can be reversed. Conclusion SIK2 can promote cisplatin resistance caused by aerobic glycolysis of breast cancer cells through PI3K/AKT/mTOR signaling pathway, which may be a new target to improve cisplatin resistance of breast cancer cells.

scholarly journals Screening antiproliferative drug for breast cancer from bisbenzylisoquinoline alkaloid tetrandrine and fangchinoline derivatives by targeting BLM helicase

BMC Cancer ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Wangming Zhang ◽  
Shuang Yang ◽  
Jinhe Liu ◽  
Linchun Bao ◽  
He Lu ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Dna Binding ◽  
Small Molecules ◽  
Cancer Cells ◽  
Small Molecule ◽  
Breast Cancer Cells ◽  
Dna Unwinding ◽  
Protein Levels ◽  
Blm Helicase ◽  
Bisbenzylisoquinoline Alkaloids

Abstract Background The high expression of BLM (Bloom syndrome) helicase in tumors involves its strong association with cell expansion. Bisbenzylisoquinoline alkaloids own an antitumor property and have developed as candidates for anticancer drugs. This paper aimed to screen potential antiproliferative small molecules from 12 small molecules (the derivatives of bisbenzylisoquinoline alkaloids tetrandrine and fangchinoline) by targeting BLM642–1290 helicase. Then we explore the inhibitory mechanism of those small molecules on proliferation of MDA-MB-435 breast cancer cells. Methods Fluorescence polarization technique was used to screen small molecules which inhibited the DNA binding and unwinding of BLM642–1290 helicase. The effects of positive small molecules on the ATPase and conformation of BLM642–1290 helicase were studied by the malachite green-phosphate ammonium molybdate colorimetry and ultraviolet spectral scanning, respectively. The effects of positive small molecules on growth of MDA-MB-435 cells were studied by MTT method, colony formation and cell counting method. The mRNA and protein levels of BLM helicase in the MDA-MB-435 cells after positive small molecule treatments were examined by RT-PCR and ELISA, respectively. Results The compound HJNO (a tetrandrine derivative) was screened out which inhibited the DNA binding, unwinding and ATPase of BLM642–1290 helicase. That HJNO could bind BLM642–1290helicase to change its conformationcontribute to inhibiting the DNA binding, ATPase and DNA unwinding of BLM642–1290 helicase. In addition, HJNO showed its inhibiting the growth of MDA-MB-435 cells. The values of IC50 after drug treatments for 24 h, 48 h and 72 h were 19.9 μmol/L, 4.1 μmol/L and 10.9 μmol/L, respectively. The mRNA and protein levels of BLM helicase in MDA-MB-435 cells increased after HJNO treatment. Those showed a significant difference (P < 0.05) compared with negative control when the concentrations of HJNO were 5 μmol/L and 10 μmol/L, which might contribute to HJNO inhibiting the DNA binding, ATPase and DNA unwinding of BLM helicase. Conclusion The small molecule HJNO was screened out by targeting BLM642–1290 helicase. And it showed an inhibition on MDA-MB-435 breast cancer cells expansion.

scholarly journals Cellular Mechanisms of Metabolic Remodeling During Fluid Sheer Stress-Induced Metastasis

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 322-322
Author(s):  
Tracie Dunn ◽  
Spenser Brown ◽  
Nelli Mnatsakanyan ◽  
Elizabeth Jonas ◽  
Kim Yonghyun ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Energy Metabolism ◽  
Cancer Cells ◽  
Atp Synthase ◽  
Breast Cancer Cells ◽  
Transport Systems ◽  
Cellular Mechanisms ◽  
Sheer Stress ◽  
Metabolic Remodeling ◽  
C Subunit

Abstract Objectives Fluid sheer stress (FSS) is a physical stimuli of circulating tumor cells responsible for development of and progression to cancer. FSS is reported to enhance chemoresistance and proliferation in breast cancer cells. However, cellular mechanisms explaining how FSS contributes to the metastatic phenotype of breast cancer cell are less known. Chemoresistance is highly dependent upon active transport systems, and cell division and growth require ATP. In this study, we hypothesize that FSS contributes to mitochondrial remodeling and leads to alterations in energy metabolism which favor metastasis. Methods MDA-MB-231 human breast cancer cells were exposed to fluid sheer stress (FSS). MDA-MB-231 cells were then grown in culture media for 24 h, and intracellular energy (ATP) and abundance of ATP synthase were analyzed. Results FSS significantly increases intracellular ATP in MDA-MB-231 breast cancer cells. Interestingly, MDA-MB-231 cells retained increased ATP after treatment with the uncoupler FCCP indicating remodeling and decreased reliance on mitochondrial energy metabolism. We then quantified the abundance of ATP synthase, the key enzyme complex that produces mitochondrial ATP. FSS significantly decreased protein levels of the c-subunit of ATP synthase. Conclusions Our data show that FSS causes metabolic remodeling of mitochondria-dependent ATP production. We suggest that the c-subunit of ATP synthase is an important target of FSS-mediated metastasis. Strategies to enhance the abundance or activity of the c-subunit may prevent metabolic remodeling-associated with metastasis in FSS-exposed circulating cancer cells. Funding Sources Alabama Life Research Institute (ALRI) 14,565.

scholarly journals Trastuzumab in combination with AT-101 induces cytotoxicity and apoptosis in Her2 positive breast cancer cells

2020 ◽  
Vol 16 (3) ◽  
pp. 4485-4495
Author(s):  
Gulcan Bulut ◽  
Harika Atmaca ◽  
Burcak Karaca
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Cell Lines ◽  
Breast Cancer Cells ◽  
Breast Cancer Cell Lines ◽  
Her2 Positive ◽  
Protein Levels ◽  
Her2 Positive Breast Cancer ◽  
Synergistic Cytotoxicity ◽  
Positive Breast Cancer

Aim: AT-101 is a polyphenolic compound with potent anti-apoptotic effects in various cancers. In this study, the possible synergistic cytotoxic and apoptotic effect of trastuzumab/AT-101 combination was investigated in HER2-positive breast cancer cell lines. Materials & methods: SKBR-3, MDA-MB-453 and MCF-10A cell lines were treated with a trastuzumab/AT-101 combination. Synergistic cytotoxicity and apoptosis effects were shown and then PI3K and Akt protein levels were studied. Result: The trastuzumab/AT-101 combination induced synergistic cytotoxicity and apoptosis in both breast cancer cells but not in MCF-10A cells. Combination treatment induced cytotoxicity via inhibiting PI3K/AKT but not the MAPK/ERK pathway. Conclusion: The trastuzumab/AT-101 combination may be a good candidate for patients with trastuzumab-resistant Her2-positive breast cancer and inhibition of the PI3K/AKT pathway may be one of the underlying mechanisms.

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