scholarly journals G-Protein Inwardly Rectifying Potassium Channel 1 (GIRK1) Knockdown Decreases Beta-Adrenergic, MAP Kinase and Akt Signaling in the MDA-MB-453 Breast Cancer Cell Line

2008 ◽  
Vol 1 ◽  
pp. BCBCR.S629
Author(s):  
Michael W. Hance ◽  
Madhu S. Dhar ◽  
Howard K. Plummer

Previous data from our laboratory have indicated that there is a functional link between the beta-adrenergic receptor signaling pathway and the G-protein inwardly rectifying potassium channel (GIRK1) in breast cancer cell lines and that these pathways are involved in growth regulation of these cells. To determine functionality, MDA-MB-453 breast cancer cells were stimulated with ethanol, known to open GIRK channels. Decreased GIRK1 protein levels were seen after treatment with 0.12% ethanol. In addition, serum-free media completely inhibited GIRK1 protein expression. This data indicates that there are functional GIRK channels in breast cancer cells and that these channels are involved in cellular signaling. In the present research, to further define the signaling pathways involved, we performed RNA interference (siRNA) studies. Three stealth siRNA constructs were made starting at bases 1104, 1315, and 1490 of the GIRK1 sequence. These constructs were transfected into MDA-MB-453 cells, and both RNA and protein were isolated. GIRK1, β2-adrenergic and 18S control levels were determined using real-time PCR 24 hours after transfection. All three constructs decreased GIRK1 mRNA levels. However, β2 mRNA levels were unchanged by the GIRK1 knockdown. GIRK1 protein levels were also reduced by the knockdown, and this knockdown led to decreases in beta-adrenergic, MAP kinase and Akt signaling.

2020 ◽  
Vol 21 (9) ◽  
pp. 3337 ◽  
Author(s):  
Hana Jin ◽  
Hye Jung Kim

The inflammasomes are reported to be associated with tumor progression. In our previous study, we determined that extracellular ATP enhances invasion and tumor growth by inducing inflammasome activation in a P2Y purinergic receptor 2 (P2Y2R)-dependent manner. However, it is not clear which inflammasome among the diverse complexes is associated with P2Y2R activation in breast cancer. Thus, in this study, we determined which inflammasome components are regulated by P2Y2R activation and are involved in tumor progression in breast cancer cells and radiotherapy-resistant (RT-R)-breast cancer cells. First, we found that NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3); NLR family caspase activation and recruitment domain (CARD) containing 4 (NLRC4); apoptosis-associated speck-like protein containing a CARD complex (ASC); and caspase-1 mRNA levels were upregulated in RT-R-MDA-MB-231 cells compared to MDA-MB-231 cells, whereas tumor necrosis factor-α (TNF-α) or ATP treatment induced NLRC4, ASC, and caspase-1 but not NLRP3 protein levels. Moreover, TNF-α or ATP increased protein levels of NLRC4, ASC, and caspase-1 in a P2Y2R-dependent manner in MDA-MB-231 and RT-R-MDA-MB-231 cells. In addition, P2Y2R activation by ATP induced the secretion of IL-1β and VEGF-A, as well as invasion, in MDA-MB-231 and RT-R-MDA-MB-231 cells, which was inhibited by NLRC4, ASC, and caspase-1 small interfering RNA (siRNA). Taken together, this report suggests that P2Y2R activation by ATP induces tumor invasion and angiogenesis through inflammasome activation, specifically by regulating the inflammasome components NLRC4, ASC, and caspase-1.


1995 ◽  
Vol 14 (3) ◽  
pp. 391-394 ◽  
Author(s):  
S Y James ◽  
A G Mackay ◽  
K W Colston

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.


2020 ◽  
Vol 9 ◽  
pp. 1812
Author(s):  
Solmaz Rahmani Barouji ◽  
Arman Shahabi ◽  
Mohammadali Torbati ◽  
Seyyed Mohammad Bagher Fazljou ◽  
Ahmad Yari Khosroushahi

Background: Mummy (Iranian pure shilajit) is a remedy with possessing anti-inflammatory, antioxidant and anticancer activities. This study aimed to examine mummy effects on epithelial-mesenchymal transition (EMT) and invasiveness of MCF-7 and MDA-MB-231 breast cancer (BC) cell lines with underlying its mechanism. Materials and Methods: The dose-dependent inhibitory effect of the mummy on cell proliferation in vitro was determined using the MTT assay.  Flow cytometry and 4’,6-diamidino-2-phenylindole dihydrochloride staining were respectively used for quantitative and qualitative analysis of cellular apoptosis, and gene expression analysis was conducted using real-time PCR. Results: MDA-MB-231 showed more sensitivity than the MCF-7 cell line to the anticancer activity of mummy, while mummy did not exhibit significant cell cytotoxicity against human normal cells (MCF-10A). The gene expression profile demonstrated a significant decrease in TGF-β1, TGF-βR1, TWIST1, NOTCH1, CTNNB1, SRC along with an increase in E-cadherin mRNA levels in mummy treated cells compared to the untreated control group (P≤0.05). Conclusion: Mummy triggers inhibition of EMT and metastasis in breast cancer cells mainly through the downregulation of TGFβ1 activity, and more studies required to find its specific anticancer activity with details. [GMJ.2020;9:e1812]


2009 ◽  
Vol 37 (01) ◽  
pp. 159-167 ◽  
Author(s):  
Mi-Kyung Park ◽  
Hyeok-Yi Kwon ◽  
Woong-Shick Ahn ◽  
Sumi Bae ◽  
Mee-Ra Rhyu ◽  
...  

We studied the estrogenic activity and cellular effect of wild yam extract in MCF-7 human breast cancer cells. The extract increased the activity of the progesterone receptor and pS2 genes at the mRNA levels in human breast cancer MCF-7 cells, although the effects were not as prominent as those of 17β-estradiol (E2). Western blot analysis showed that the level of estrogen receptor α protein was down-regulated after treatment with E2 or wild yam extract. Wild yam extract also inhibited proliferation of MCF-7 cells. These data indicate that wild yam extract acts as a weak phytoestrogen and protects against proliferation in human breast carcinoma MCF-7 cells.


2021 ◽  
Vol 17 (8) ◽  
pp. 1545-1553
Author(s):  
Chuanguang Xiao ◽  
Xiaohong Wang ◽  
Jiacheng Shen ◽  
Yanjie Xia ◽  
Shusheng Qiu ◽  
...  

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.


2020 ◽  
Author(s):  
Shoukai Zong ◽  
Wei Dai ◽  
Wencheng Fang ◽  
Xiangting Guo ◽  
Kai Wang

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.


2020 ◽  
Vol 2020 ◽  
pp. 1-12 ◽  
Author(s):  
Xiao-jun Gou ◽  
Huan-huan Bai ◽  
Li-wei Liu ◽  
Hong-yu Chen ◽  
Qi Shi ◽  
...  

Objective. To explore the ability of asiatic acid to interfere with the invasion and proliferation of breast cancer cells by inhibiting WAVE3 expression and activation through the PI3K/AKT signaling pathway. Methods. The MDA-MB-231 cells with strong invasiveness were screened by transwell assay, and plasmids with high expression of WAVE3 were constructed for transfection. The transfection effect and protein expression level of plasmids were verified by PCR and WB. The effects of asiatic acid on cell proliferation and invasion were investigated by flow cytometry. The xenografted tumor models in nude mice were established to study the antitumor activity of asiatic acid. Results. Asiatic acid significantly inhibited the activity of MDA-MB-231 cells, and the expression level of WAVE3 increased significantly in the tissue of ductal carcinoma in situ and was lower than that in the metastasis group. After plasmid transfection, the mRNA and protein expression of WAVE3 increased significantly in the cells. Asiatic acid at different concentrations had an impact on cell apoptosis and invasion and could significantly inhibit the expression of WAVE3, P53, p-PI3K, p-AKT, and other proteins. The T/C(%) of asiatic acid (50 mg/kg) for MDA-MB-231(F10) xenografted tumor in nude mice was 46.33%, with a tumor inhibition rate of 59.55%. Asiatic acid could significantly inhibit the growth of MDA-MB-231 (F10) xenografted tumors in nude mice (p<0.05). Conclusions. Asiatic acid interferes with the ability of breast cancer cells to invade and proliferate by inhibiting WAVE3 expression and activation and the mechanism of action may be related to the PI3K/AKT signaling pathway.


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