Effect of Multikinase Inhibitors on Caspase-Independent Cell Death and DNA Damage in HER2-Overexpressing Breast Cancer Cells

Abstract Background Radioresistance can pose a significant obstacle to the effective treatment of breast cancers. Epithelial–mesenchymal transition (EMT) is a critical step in the acquisition of stem cell traits and radioresistance. Here, we investigated whether Maprang seed extract (MPSE), a gallotannin-rich extract of seed from Bouea macrophylla Griffith, could inhibit the radiation-induced EMT process and enhance the radiosensitivity of breast cancer cells. Methods Breast cancer cells were pre-treated with MPSE before irradiation (IR), the radiosensitizing activity of MPSE was assessed using the colony formation assay. Radiation-induced EMT and stemness phenotype were identified using breast cancer stem cells (CSCs) marker (CD24−/low/CD44+) and mammosphere formation assay. Cell motility was determined via the wound healing assay and transwell migration. Radiation-induced cell death was assessed via the apoptosis assay and SA-β-galactosidase staining for cellular senescence. CSCs- and EMT-related genes were confirmed by real-time PCR (qPCR) and Western blotting. Results Pre-treated with MPSE before irradiation could reduce the clonogenic activity and enhance radiosensitivity of breast cancer cell lines with sensitization enhancement ratios (SERs) of 2.33 and 1.35 for MCF7 and MDA-MB231cells, respectively. Pretreatment of breast cancer cells followed by IR resulted in an increased level of DNA damage maker (γ-H2A histone family member) and enhanced radiation-induced cell death. Irradiation induced EMT process, which displayed a significant EMT phenotype with a down-regulated epithelial marker E-cadherin and up-regulated mesenchymal marker vimentin in comparison with untreated breast cancer cells. Notably, we observed that pretreatment with MPSE attenuated the radiation-induced EMT process and decrease some stemness-like properties characterized by mammosphere formation and the CSC marker. Furthermore, pretreatment with MPSE attenuated the radiation-induced activation of the pro-survival pathway by decrease the expression of phosphorylation of ERK and AKT and sensitized breast cancer cells to radiation. Conclusion MPSE enhanced the radiosensitivity of breast cancer cells by enhancing IR-induced DNA damage and cell death, and attenuating the IR-induced EMT process and stemness phenotype via targeting survival pathways PI3K/AKT and MAPK in irradiated breast cancer cells. Our findings describe a novel strategy for increasing the efficacy of radiotherapy for breast cancer patients using a safer and low-cost natural product, MPSE.

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Exploring the Molecular Mechanism of Cinnamic Acid-Mediated Cytotoxicity in Triple Negative MDA-MB-231 Breast Cancer Cells

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520620666200807222248 ◽

2020 ◽

Vol 20 ◽

Author(s):

Ambika Pal ◽

Poulami Tapadar ◽

Ranjana Pal

Keyword(s):

Breast Cancer ◽

Dna Damage ◽

Cell Death ◽

Cancer Cells ◽

Cinnamic Acid ◽

Mtt Assay ◽

Trypan Blue ◽

Breast Cancer Cells ◽

Triple Negative ◽

Caspase 8

Background: Cinnamic acid (CA), also known as 3-phenyl-2-propenoic acid, is a naturally occurring aromatic fatty acid found commonly in cinnamon, grapes, tea, cocoa, spinach and celery. Various studies have identified CA to have anti-proliferative action on glioblastoma, melanoma, prostate and lung carcinoma cells. Objective: Our objective was to investigate the molecular mechanism underlying the cytotoxic effect of CA in killing MDA-MB-231 triple negative breast cancer cells. Methods: We performed MTT assay and trypan blue assay to determine cell viability and cell death, respectively. Comet analysis was carried out to investigate DNA damage of individual cells. Furthermore, AO/EtBr assay and sub-G1 analysis using flowcytometry was used to study apoptosis. Protein isolation followed by immunoblotting was used to observe protein abundance in treated and untreated cancer cells. Results: Using MTT assay we have determined CA to reduce cell viability in MDA-MB-231 breast cancer cells and tumorigenic HEK 293 cells but not in normal NIH3T3 fibroblast cells. Subsequently, trypan blue assay and comet assay showed CA to cause cell death and DNA damage, respectively, in the MDA-MB-231 cells. Using AO/EtBr staining and sub-G1 analysis we further established CA to increase apoptosis. Additionally, immunoblotting showed the abundance of TNFA, TNF receptor 1 (TNFR1) and cleaved caspase-8/-3 pro-apoptotic proteins to increase on CA treatment. Subsequently, blocking of TNFA-TNFR1 signalling by small molecule inhibitor, R-7050, reduced the expression of cleaved caspase-8 and caspase-3 at the protein level. Conclusion: Thus, from the above observations we can conclude that CA is an effective anticancer agent that can induce apoptosis in breast cancer cells via TNFA-TNFR1 mediated extrinsic apoptotic pathway.

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Abstract 4639: Blockade of MDM2-mediated signaling in context of DNA damage increases E2F1 expression and enhances cell death in triple-negative breast cancer cells.

10.1158/1538-7445.am2013-4639 ◽

2013 ◽

Author(s):

Eva Tonsing-Carter ◽

Harlan E. Shannon ◽

Barbara J. Bailey ◽

Lindsey D. Mayo ◽

Karen E. Pollok

Keyword(s):

Breast Cancer ◽

Dna Damage ◽

Cell Death ◽

Cancer Cells ◽

Triple Negative Breast Cancer ◽

Breast Cancer Cells ◽

Triple Negative ◽

E2f1 Expression

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Cucurbita ficifolia Fruit Extract Induces Tp53/Caspase-Mediated Apoptosis in MCF-7 Breast Cancer Cells

BioMed Research International ◽

10.1155/2020/3712536 ◽

2020 ◽

Vol 2020 ◽

pp. 1-11

Author(s):

Ghedeir M. Alshammari ◽

Aristatile Balakrishnan ◽

Ali A. Alshatwi ◽

Abdulrahman Al-Khalifa

Keyword(s):

Breast Cancer ◽

Dna Damage ◽

Cell Death ◽

Programmed Cell Death ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Time Dependent ◽

Fruit Extract ◽

Cucurbita Ficifolia ◽

Mcf 7

The second most biggest cancer worldwide is breast cancer. There is an increasing need for safer, effective, and affordable drug candidates from natural sources to treat breast cancer. In the present investigation, the anticancer effect of Cucurbita ficifolia Bouché (C. ficifolia) fruit extract was tested on the human breast cancer cells such as MCF-7. The cells were exposed with different doses of C. ficifolia, for the assessment of IC50 concentrations on the MCF-7 cell lines for 24 hs. The effect of C. ficifolia fruit extract on morphological and apoptotic changes were evaluated by specific fluorescence staining techniques and real-time PCR in a time-dependent manner for 24 hs and 48 hs. The IC50 value for C. ficifolia fruit extract was found to be 90 μg/mL. Morphological alteration and apoptotic distinctiveness aspect like chromatin condensation and nuclear fragmentation were noticed in C. ficifolia extract exposed breast cancer cells. Further, we observed that C. ficifolia extract-induced programmed cell death in the MCF-7 cells were mediated with the elevated expression of the tumor suppressor gene such as p53 and apoptotic markers such as caspase-8, caspase-9, caspase-3, fatty acid synthase (FAS), Fas-associated protein with death domain (FADD), Bcl-2 homologous antagonist/killer (BAK), and Bcl-2-associated X protein (BAX). These observations established that C. ficifolia significantly concealed the cell division and provoked p53/caspase-mediated programmed cell death. Further, we noticed that this cell death in MCF-7 cells is concentration and time dependent. As evaluated through the comet assay, C. ficifolia induced DNA damage; further upon increasing the duration of the treatment, the DNA damage was higher than before. Thus, our study concludes that C. ficifolia could serve as an effective anticancer agent through vital gene modulation.

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