scholarly journals Autophagic cell death, polyploidy and senescence induced in breast tumor cells by the substituted pyrrole JG-03-14, a novel microtubule poison

2007 ◽  
Vol 74 (7) ◽  
pp. 981-991 ◽  
Author(s):  
Christopher R. Arthur ◽  
John T. Gupton ◽  
Glen E. Kellogg ◽  
W. Andrew Yeudall ◽  
Myles C. Cabot ◽  
...  
1996 ◽  
Vol 51 (7) ◽  
pp. 931-940 ◽  
Author(s):  
Frank A. Fornari ◽  
W.David Jarvis ◽  
Steven Grant ◽  
Michael S. Orr ◽  
Joyce K. Randolph ◽  
...  

2020 ◽  
Author(s):  
Tahiyat Alothaim ◽  
Morgan Charbonneau ◽  
Xiaohu Tang

Abstract IntroductionTriple-negative breast cancer (TNBC) is a highly malignant breast cancer type with poor prognosis and lacks effective therapy. TNBC is not responsive to targeted therapy for hormone receptors and often exhibit resistance to current chemotherapeutic agents. Targeting tumor metabolism is an emergent strategy to treat cancer. Therefore, identification of tumor metabolic deregulations and development of effective targeted therapies are urgently needed.MethodsWe performed the epigenetic compound library screening in claudin-high breast tumor cells and identified therapeutical sensitizers to overcome the drug resistance of targeted cysteine-dependence therapy. Gene expression profiling were generated to analyze signaling pathways induced by the combined tubacin and cysteine deprivation treatment. Specific inhibitors, shRNA, and CRISPR/Cas9 gene editing approaches were used to target cellular proteins HDAC6 and PKCγ and examine their roles in cell death. Cell viability, RT-qPCR, and Western blotting assays were performed in cysteine-independent tumor cells to examine the anticancer effects of combined tubacin and cysteine deprivation treatment. ResultsWe found that TNBC has differential death responses to cysteine deprivation and the cysteine-dependence of TNBC corelates with the expression levels of claudin genes in addition to the classical EMT markers. To overcome drug resistance in claudin-high/cysteine-independent breast tumor cells, HDAC6 inhibitors were identified by the epigenetic compound library screening as potent sensitizers that synergize with cysteine deprivation to eradicate cysteine-independent tumor cells. Unexpectedly, HDAC6 knockout did not recapitulate the HDAC6 inhibitors-mediated synthetic lethality, indicating that HDAC6 is not the actual target of HDAC6 inhibitors in this context. Transcriptomic profiling revealed that HDAC6 inhibitors synergizes with cysteine depletion to trigger a profound gene transcriptional program. Notably, a zinc-related gene response was observed to accompany with a prominent increase of labile zinc in cells during cell death. We further showed that activation of PKCγ signaling is required to interfere cellular zinc homeostasis and drive HDAC6 inhibitors-mediated cell death.ConclusionOur study demonstrated that HDAC6 inhibitors function as potent sensitizers to overcome the resistance of cysteine deprivation in claudin-high breast tumor cells. Identification of such sensitizers would make the targeted cysteine-dependence therapy applicable in various subtypes of breast cancer.


Author(s):  
Saeideh Jafarinejad-Farsangi ◽  
Mahnaz Sadat Hashemi ◽  
Seyede Elmira Yazdi Rouholamini ◽  
Sedigheh Gharbi ◽  
Zeinab Ansari-Asl ◽  
...  

Author(s):  
Tatiane Renata Fagundes ◽  
Bruna Bortoleti ◽  
Priscila Camargo ◽  
Vírgínia Concato ◽  
Fernanda Tomiotto-Pellissier ◽  
...  

Background: Conventional therapies for breast cancer is still a challenge due to use of cytotoxic drugs not highly effective with major adverse effects. Thiohydantoins, are biologically active heterocyclic compounds reported by several biological activities, including anticarcinogenic properties, i.e., this work aimed to assess the use of thiohydantoin as a potential antitumor agent against MCF-7 breast cancer cells. Methods: MTT and neutral red assays were used to assess the possible cytotoxic activity of compounds against MCF-7 cells. Cell volume measurement and analysis were performed by flow cytometry, fluorescence analysis was carried out to determine patterns of cell death induced by thiohydantoins. Results: The treatment with micromolar doses of thiohydantoins promoted a decrease in the viability of MCF-7 breast tumor cells. Also were observed the increase in ROS and NO production, reduction in cell volume, loss of membrane integrity, mitochondrial depolarization, and increased fluorescence for annexin V and caspase-3. These findings indicate cell death by apoptosis and increased formation of autophagic vacuoles and stopping the cell cycle in the G1/ G0 phase. Conclusions: Our results indicate that thiohydantoins are cytotoxic to breast tumor cells, and this effect is linked to the increase in ROS production. This phenomenon changes tumorigenic pathways, that lead to a halt of the cell cycle in G1/G0, an important checkpoint for DNA errors, which may have altered the process by which cells produce energy, causing a decrease in mitochondrial viability and thus leading to the apoptotic process. Furthermore, the results indicate increased autophagy, a vital process linked to a decrease in lysosomal viability and considered as a cell death and tumor suppression mechanism.


2010 ◽  
Vol 649 (1-3) ◽  
pp. 135-139 ◽  
Author(s):  
Da Hee Oh ◽  
Jun Soo Bang ◽  
Hyun Mi Choi ◽  
Hyung-In Yang ◽  
Myung Chul Yoo ◽  
...  

BIOCELL ◽  
2018 ◽  
Vol 42 (1) ◽  
pp. 17-24 ◽  
Author(s):  
B. Zhang ◽  
Y. Zhang ◽  
X. Zhang ◽  
Y. LV

Sign in / Sign up

Export Citation Format

Share Document