Properties and gene expression profiling of acquired radioresistance in mouse breast cancer cells

Abstract

Background: Acquired radioresistant cells exhibit many characteristic changes which may influence cancer progression and further treatment options. The purpose of this study is to investigate the changes of radioresistant human epidermal growth factor receptor 2 (HER2)-positive breast cancer cells on both phenotypic and molecular levels. Methods:We established an acquired radioresistant cell line from its parental NF639 cell line (HER2positive) by fractionated radiation and assessed changes in cellular morphology, proliferation, migration, anti-apoptosis activity, basal reactive oxygen species (ROS) level and energy metabolism. RNA-sequencing (RNA-seq) was also used to reveal the potential regulating genes and molecular mechanisms associated with the acquired changed phenotypes. Real-time PCR was used to validate the results of RNA-seq.Results: The NF639R cells exhibited increased radioresistance and enhanced activity of proliferation, migration and anti-apoptosis, but decreased basal ROS. Two main energy metabolism pathways, mitochondrial respiration and glycolytic, were also upregulated. Furthermore, 490 differentially expressed genes were identified by RNA-seq. Enrichment analysis based on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes showed many differently expressed genes were significantly enriched in cell morphology, proliferation, migration, anti-apoptosis, antioxidation, tumor stem cells and energy metabolism and the signaling cascades such as the transforming growth factor-β, Wnt, Hedgehog, vascular endothelial growth factor, retinoic acid-inducible gene I (RIG-I)-like receptor, Toll-like receptor and nucleotide oligomerization domain (NOD)-like receptor were significantly altered in NF639R cells. Conclusions:In clinical radiotherapy, repeat radiotherapy for short-term recurrence of breast cancer may result in enhanced radioresistance and promote malignant progression. Our research provided hints to understand the tumor resistance to radiotherapy de novo and recurrence with a worse prognosis following radiotherapy.

PI3K/AKT/mTOR pathway, hypoxia, and glucose metabolism: Potential targets to overcome radioresistance in small cell lung cancer

“…High glycolytic states of cancers significantly correlate with radiation resistance and aggressive biological behavior. 15 , 16 The Warburg effect is involved in resistance to radiotherapy and/or chemotherapy. 17 The PPP is another branch of glucose metabolism, and tumor cells upregulate the PPP to produce reductive metabolites and detoxify chemoradiotherapy-induced reactive oxygens species (ROS).…”

Extracellular Vesicles and Cancer Stem Cells in Tumor Progression: New Therapeutic Perspectives

“…CSCs are also resistant to radiotherapies and their induced damage [ 97 ]. There are different signaling pathways involved in radioresistance, such as phosphatidylinositol3-kinase (PI3K), mitogen-activated protein kinase (MAPK), sirtuin (SIRT) pathways, Wnt/β-catenin signaling, interleukin 22 receptor subunit alpha 1/signal transducer and activator of transcription 3 (IL22RA1/STAT3) signaling, and sonic hedgehog signaling [ 98 ]. In regard to breast cancer, radioresistant MDA-MB-231 breast cancer cells (RT-R-MDA-MB-231 cells) are malignant cells with a high metastatic activity, proliferation rate, and expression of CSC and EMT markers [ 99 ].…”

The Role of the CREB Protein Family Members and the Related Transcription Factors in Radioresistance Mechanisms

“…Most tumour cells show high levels of constitutive NF-κB activity, with increased cell survival promoted through antagonism of apoptotic pathways [65]. A key role of the NF-κB pathway is the promotion of the innate immune response through transcription of proinflammatory mediators, including chemokines, cytokines, antimicrobial peptides, and adhesion molecules [66,67]. The NF-κB family members include NF-κB1 (p50, p105), NF-κB2 (p52, p100), RelA (p65), c-Rel, and RelB [68].…”