scholarly journals Resistance to BET inhibitors in lung adenocarcinoma is mediated by casein kinase phosphorylation of BRD4

Oncogenesis ◽  
2021 ◽  
Vol 10 (3) ◽  
Author(s):  
Jack Calder ◽  
Amy Nagelberg ◽  
Jennifer Luu ◽  
Daniel Lu ◽  
William W. Lockwood
Keyword(s):  
Lung Adenocarcinoma ◽  
Cell Lines ◽  
Epithelial Mesenchymal Transition ◽  
Pi3k Pathway ◽  
Resistant Cell ◽  
Casein Kinase ◽  
Model Systems ◽  
Cancer Type ◽  
Mesenchymal Transition ◽  
Bet Inhibitors

AbstractTargeting the epigenome to modulate gene expression programs driving cancer development has emerged as an exciting avenue for therapeutic intervention. Pharmacological inhibition of the bromodomain and extraterminal (BET) family of chromatin adapter proteins has proven effective in this regard, suppressing growth of diverse cancer types mainly through downregulation of the c-MYC oncogene, and its downstream transcriptional program. While initially effective, resistance to BET inhibitors (BETi) typically occurs through mechanisms that reactivate MYC expression. We have previously shown that lung adenocarcinoma (LAC) is inhibited by JQ1 through suppression of FOSL1, suggesting that the epigenetic landscape of tumor cells from different origins and differentiation states influences BETi response. Here, we assessed how these differences affect mechanisms of BETi resistance through the establishment of isogenic pairs of JQ1 sensitive and resistant LAC cell lines. We found that resistance to JQ1 in LAC occurs independent of FOSL1 while MYC levels remain unchanged between resistant cells and their JQ1-treated parental counterparts. Furthermore, while epithelial–mesenchymal transition (EMT) is observed upon resistance, TGF-β induced EMT did not confer resistance in JQ1 sensitive LAC lines, suggesting this is a consequence, rather than a driver of BETi resistance in our model systems. Importantly, siRNA knockdown demonstrated that JQ1 resistant cell lines are still dependent on BRD4 expression for survival and we found that phosphorylation of BRD4 is elevated in resistant LACs, identifying casein kinase 2 (CK2) as a candidate protein mediating this effect. Inhibition of CK2, as well as downstream transcriptional targets of phosphorylated BRD4—including AXL and activators of the PI3K pathway—synergize with JQ1 to inhibit BETi resistant LAC. Overall, this demonstrates that the mechanism of resistance to BETi varies depending on cancer type, with LAC cells developing JQ1 resistance independent of MYC regulation, and identifying CK2 phosphorylation of BRD4 as a potential target to overcome resistance in this cancer.

scholarly journals Piperine Inhibits TGF-β Signaling Pathways and Disrupts EMT-Related Events in Human Lung Adenocarcinoma Cells

Medicines ◽  
2020 ◽  
Vol 7 (4) ◽  
pp. 19 ◽  
Author(s):  
Leonardo Marques da Fonseca ◽  
Lucas Rodrigues Jacques da Silva ◽  
Jhenifer Santos dos Reis ◽  
Marcos André Rodrigues da Costa Santos ◽  
Victoria de Sousa Chaves ◽  
...  
Keyword(s):  
Lung Adenocarcinoma ◽  
Cell Lines ◽  
A549 Cell ◽  
Epithelial Mesenchymal Transition ◽  
Metastatic Cancer ◽  
Breast Adenocarcinoma ◽  
Mesenchymal Transition ◽  
Ic50 Values ◽  
Hepg2 Cell Lines ◽  
Tgf Β1

Background: Piperine, an amide extracted from the Piper spices, exhibits strong anti-tumor properties. However, its effect on the epithelial–mesenchymal transition (EMT) process has never been investigated. Herein, we evaluate the toxic effect of piperine on lung adenocarcinoma (A549), breast adenocarcinoma (MDA-MB-231) and hepatocellular carcinoma (HepG2) cell lines, as well as its ability to inhibit EMT-related events induced by TGF-β1 treatment. Methods: The cell viability was investigated by MTT assay. Protein expression was evaluated by Western blot. Gene expression was monitored by real-time PCR. Zymography assay was employed to detect metalloproteinase (MMP) activity in conditioned media. Cell motility was assessed by the wound-healing and phagokinetic gold sol assays. Results: The results revealed that piperine was cytotoxic in concentrations over 100 µM, showing IC50 values for HepG2, MDA-MB-231 and A549 cell lines of 214, 238 and 198 µM, respectively. In order to investigate whether piperine would reverse the TGF-β1 induced-EMT, the A549 cell line was pretreated with sublethal concentrations of the natural amide followed by the addition of TGF-β1. Besides disrupting EMT-related events, piperine also inhibited both ERK 1/2 and SMAD 2 phosphorylation. Conclusions: These results suggest that piperine might be further used in therapeutic strategies for metastatic cancer and EMT-related disorders.

scholarly journals Fbxw7 is a driver of uterine carcinosarcoma by promoting epithelial-mesenchymal transition

2019 ◽  
Vol 116 (51) ◽  
pp. 25880-25890 ◽  
Author(s):  
Ileana C. Cuevas ◽  
Subhransu S. Sahoo ◽  
Ashwani Kumar ◽  
He Zhang ◽  
Jill Westcott ◽  
...  
Keyword(s):  
Endometrial Cancer ◽  
Epithelial Mesenchymal Transition ◽  
Genetic Model ◽  
Precancerous Lesions ◽  
Lineage Tracing ◽  
Model Systems ◽  
Cancer Type ◽  
Cell Of Origin ◽  
Uterine Carcinosarcoma ◽  
Mesenchymal Transition

Uterine carcinosarcoma is an aggressive variant of endometrial carcinoma characterized by unusual histologic features including discrete malignant epithelial and mesenchymal components (carcinoma and sarcoma). Recent studies have confirmed a monoclonal origin, and comprehensive genomic characterizations have identified mutations such asTp53andPten. However, the biological origins and specific combination of driver events underpinning uterine carcinosarcoma have remained mysterious. Here, we explored the role of the tumor suppressorFbxw7in endometrial cancer through defined genetic model systems. Inactivation ofFbxw7andPtenresulted in the formation of precancerous lesions (endometrioid intraepithelial neoplasia) and well-differentiated endometrioid adenocarcinomas. Surprisingly, all adenocarcinomas eventually developed into definitive uterine carcinosarcomas with carcinomatous and sarcomatous elements including heterologous differentiation, yielding a faithful genetically engineered model of this cancer type. Genomic analysis showed that most tumors spontaneously acquiredTrp53mutations, pointing to a triad of pathways (p53, PI3K, and Fbxw7) as the critical combination underpinning uterine carcinosarcoma, and to Fbxw7 as a key driver of this enigmatic endometrial cancer type. Lineage tracing provided formal genetic proof that the uterine carcinosarcoma cell of origin is an endometrial epithelial cell that subsequently undergoes a prominent epithelial–mesenchymal transition underlying the attainment of a highly invasive phenotype specifically driven by Fbxw7.

scholarly journals Low-Dose Nicotine Activates EGFR Signaling via α5-nAChR and Promotes Lung Adenocarcinoma Progression

2020 ◽  
Vol 21 (18) ◽  
pp. 6829
Author(s):  
Mong-Lien Wang ◽  
Yi-Fan Hsu ◽  
Chih-Hsuan Liu ◽  
Ya-Ling Kuo ◽  
Yi-Chen Chen ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Lung Adenocarcinoma ◽  
Acetylcholine Receptor ◽  
Cell Lines ◽  
Nicotinic Acetylcholine Receptor ◽  
Low Dose ◽  
Epithelial Mesenchymal Transition ◽  
Clinical Specimen ◽  
Nicotinic Acetylcholine ◽  
Mesenchymal Transition

Nicotine in tobacco smoke is considered carcinogenic in several malignancies including lung cancer. The high incidence of lung adenocarcinoma (LAC) in non-smokers, however, remains unexplained. Although LAC has long been less associated with smoking behavior based on previous epidemiological correlation studies, the effect of environmental smoke contributing to low-dose nicotine exposure in non-smoking population could be underestimated. Here we provide experimental evidence of how low-dose nicotine promotes LAC growth in vitro and in vivo. Screening of nicotinic acetylcholine receptor subunits in lung cancer cell lines demonstrated a particularly high expression level of nicotinic acetylcholine receptor subunit α5 (α 5-nAChR) in LAC cell lines. Clinical specimen analysis revealed up-regulation of α 5-nAChR in LAC tumor tissues compared to non-tumor counterparts. In LAC cell lines α 5-nAChR interacts with epidermal growth factor receptor (EGFR), positively regulates EGFR pathway, enhances the expression of epithelial-mesenchymal transition markers, and is essential for low-dose nicotine-induced EGFR phosphorylation. Functionally, low-dose nicotine requires α 5-nAChR to enhance cell migration, invasion, and proliferation. Knockdown of α 5-nAChR inhibits the xenograft tumor growth of LAC. Clinical analysis indicated that high level of tumor α 5-nAChR is correlated with poor survival rates of LAC patients, particularly in those expressing wild-type EGFR. Our data identified α 5-nAChR as an essential mediator for low-dose nicotine-dependent LAC progression possibly through signaling crosstalk with EGFR, supporting the involvement of environmental smoke in tumor progression in LAC patients.

MiR-597 Targeting 14-3-3σ Enhances Cellular Invasion and EMT in Nasopharyngeal Carcinoma Cells

2019 ◽  
Vol 12 (2) ◽  
pp. 105-114 ◽  
Author(s):  
Lisha Xie ◽  
Tao Jiang ◽  
Ailan Cheng ◽  
Ting Zhang ◽  
Pin Huang ◽  
...  
Keyword(s):  
Nasopharyngeal Carcinoma ◽  
Cell Lines ◽  
Western Blotting ◽  
Molecular Mechanisms ◽  
Epithelial Mesenchymal Transition ◽  
Suppressor Gene ◽  
Migration And Invasion ◽  
Mesenchymal Transition ◽  
Downstream Target ◽  
Before And After

Background: Alterations in microRNAs (miRNAs) are related to the occurrence of nasopharyngeal carcinoma (NPC) and play an important role in the molecular mechanism of NPC. Our previous studies show low expression of 14-3-3σ (SFN) is related to the metastasis and differentiation of NPC, but the underlying molecular mechanisms remain unclear. Methods: Through bioinformatics analysis, we find miR-597 is the preferred target miRNA of 14-3-3σ. The expression level of 14-3-3σ in NPC cell lines was detected by Western blotting. The expression of miR-597 in NPC cell lines was detected by qRT-PCR. We transfected miR-597 mimic, miR-597 inhibitor and 14-3-3σ siRNA into 6-10B cells and then verified the expression of 14-3-3σ and EMT related proteins, including E-cadherin, N-cadherin and Vimentin by western blotting. The changes of migration and invasion ability of NPC cell lines before and after transfected were determined by wound healing assay and Transwell assay. Results: miR-597 expression was upregulated in NPC cell lines and repaired in related NPC cell lines, which exhibit a potent tumor-forming effect. After inhibiting the miR-597 expression, its effect on NPC cell line was obviously decreased. Moreover, 14-3-3σ acts as a tumor suppressor gene and its expression in NPC cell lines is negatively correlated with miR-597. Here 14-3-3σ was identified as a downstream target gene of miR-597, and its downregulation by miR-597 drives epithelial-mesenchymal transition (EMT) and promotes the migration and invasion of NPC. Conclusion: Based on these findings, our study will provide theoretical and experimental evidences for molecular targeted therapy of NPC.

scholarly journals Modulating Tumor Cell Functions by Tunable Nanopatterned Ligand Presentation

Nanomaterials ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 212
Author(s):  
Katharina Amschler ◽  
Michael P. Schön
Keyword(s):  
Extracellular Matrix ◽  
Tumor Cell ◽  
Cell Fate ◽  
Epithelial Mesenchymal Transition ◽  
Model Systems ◽  
Cellular Functions ◽  
Biophysical Parameters ◽  
Ligand Density ◽  
Mesenchymal Transition ◽  
Cell Functions

Cancer comprises a large group of complex diseases which arise from the misrouted interplay of mutated cells with other cells and the extracellular matrix. The extracellular matrix is a highly dynamic structure providing biochemical and biophysical cues that regulate tumor cell behavior. While the relevance of biochemical signals has been appreciated, the complex input of biophysical properties like the variation of ligand density and distribution is a relatively new field in cancer research. Nanotechnology has become a very promising tool to mimic the physiological dimension of biophysical signals and their positive (i.e., growth-promoting) and negative (i.e., anti-tumoral or cytotoxic) effects on cellular functions. Here, we review tumor-associated cellular functions such as proliferation, epithelial-mesenchymal transition (EMT), invasion, and phenotype switch that are regulated by biophysical parameters such as ligand density or substrate elasticity. We also address the question of how such factors exert inhibitory or even toxic effects upon tumor cells. We describe three principles of nanostructured model systems based on block copolymer nanolithography, electron beam lithography, and DNA origami that have contributed to our understanding of how biophysical signals direct cancer cell fate.

scholarly journals Overexpression of SERPINA3 promotes tumor invasion and migration, epithelial-mesenchymal-transition in triple-negative breast cancer cells

Breast Cancer ◽  
2021 ◽  
Author(s):  
Yingzi Zhang ◽  
Jiao Tian ◽  
Chi Qu ◽  
Yang Peng ◽  
Jinwei Lei ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Proliferation ◽  
Cell Lines ◽  
Triple Negative Breast Cancer ◽  
Triple Negative ◽  
Epithelial Mesenchymal Transition ◽  
Cell Counting ◽  
Migration And Invasion ◽  
Mesenchymal Transition ◽  
Tnbc Cell

Abstract Background Recent studies have indicated that serpin peptidase inhibitor, clade A, member 3 (SERPINA3) is a potential marker associated with tumor progression, which connoted that SERPINA3 is related to malignant phenotypes in cancer. However, the biological function of SERPINA3 in breast cancer (BC) remains unclear. Methods Bioinformatics data were downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Immunohistochemical staining (IHC) was conducted to determine SERPINA3 expression. With strong aggressive abilities, triple-negative breast cancer (TNBC) cell lines (MDA-MB-231, BT549 and MDA-MB-436) were obtained to examine SERPINA3 expression and functions. Wound healing and Transwell assays were performed to measure cell migration and invasion. Cell Counting Kit-8 (CCK-8) assay was conducted to detect cell proliferation abilities and cell viabilities. Results SERPINA3 was upregulated in BC tissues. Functional assays suggested that overexpression of SERPINA3 significantly promoted cell proliferation, where migration and invasion of TNBC cells were accelerated. Knockdown of SERPINA3 had the opposite effects. These results causing by overexpression of SERPINA3 were also confirmed in non-TNBC cell lines. Overexpression of SERPINA3 remarkably enhanced the epithelial–mesenchymal transition (EMT) by upregulating the EMT markers and EZH2. In addition, the overexpression of SERPINA3 reduced the sensitivity of TNBC cells to cisplatin. Conclusion SERPINA3 can regulate the migration, invasion and EMT of TNBC cells and increased expression of SERPINA3 confers resistance to cisplatin in TNBC cells. We discern it is required for the regulation of BC progression and is a critical target for the clinical treatment of BC.

scholarly journals Long noncoding RNA LINC00941 promotes pancreatic cancer progression by competitively binding miR-335-5p to regulate ROCK1-mediated LIMK1/Cofilin-1 signaling

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jie Wang ◽  
Zhiwei He ◽  
Jian Xu ◽  
Peng Chen ◽  
Jianxin Jiang
Keyword(s):  
Pancreatic Cancer ◽  
Cell Growth ◽  
Cell Lines ◽  
Cancer Progression ◽  
Noncoding Rna ◽  
Epithelial Mesenchymal Transition ◽  
Loss Of Function ◽  
Mesenchymal Transition

AbstractAn accumulation of evidence indicates that long noncoding RNAs are involved in the tumorigenesis and progression of pancreatic cancer (PC). In this study, we investigated the functions and molecular mechanism of action of LINC00941 in PC. Quantitative PCR was used to examine the expression of LINC00941 and miR-335-5p in PC tissues and cell lines, and to investigate the correlation between LINC00941 expression and clinicopathological features. Plasmid vectors or lentiviruses were used to manipulate the expression of LINC00941, miR-335-5p, and ROCK1 in PC cell lines. Gain or loss-of-function assays and mechanistic assays were employed to verify the roles of LINC00941, miR-335-5p, and ROCK1 in PC cell growth and metastasis, both in vivo and in vitro. LINC00941 and ROCK1 were found to be highly expressed in PC, while miR-335-5p exhibited low expression. High LINC00941 expression was strongly associated with larger tumor size, lymph node metastasis, and poor prognosis. Functional experiments revealed that LINC00941 silencing significantly suppressed PC cell growth, metastasis and epithelial–mesenchymal transition. LINC00941 functioned as a molecular sponge for miR-335-5p, and a competitive endogenous RNA (ceRNA) for ROCK1, promoting ROCK1 upregulation, and LIMK1/Cofilin-1 pathway activation. Our observations lead us to conclude that LINC00941 functions as an oncogene in PC progression, behaving as a ceRNA for miR-335-5p binding. LINC00941 may therefore have potential utility as a diagnostic and treatment target in this disease.

scholarly journals Upregulation of LINC01426 promotes the progression and stemness in lung adenocarcinoma by enhancing the level of SHH protein to activate the hedgehog pathway

2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Xiaoli Liu ◽  
Zuwei Yin ◽  
Linping Xu ◽  
Huaimin Liu ◽  
Lifeng Jiang ◽  
...  
Keyword(s):  
Lung Adenocarcinoma ◽  
Bioinformatics Analysis ◽  
Epithelial Mesenchymal Transition ◽  
Mrna Level ◽  
Hedgehog Pathway ◽  
Biological Processes ◽  
Protein Coding ◽  
Mesenchymal Transition ◽  
Functional Roles ◽  
Rip Assay

AbstractLong noncoding RNAs (lncRNAs) play crucial roles in regulating a variety of biological processes in lung adenocarcinoma (LUAD). In our study, we mainly explored the functional roles of a novel lncRNA long intergenic non-protein coding RNA 1426 (LINC01426) in LUAD. We applied bioinformatics analysis to find the expression of LINC01426 was upregulated in LUAD tissue. Functionally, silencing of LINC01426 obviously suppressed the proliferation, migration, epithelial–mesenchymal transition (EMT), and stemness of LUAD cells. Then, we observed that LINC01426 functioned through the hedgehog pathway in LUAD. The effect of LINC01426 knockdown could be fully reversed by adding hedgehog pathway activator SAG. In addition, we proved that LINC01426 could not affect SHH transcription and its mRNA level. Pull-down sliver staining and RIP assay revealed that LINC01426 could interact with USP22. Ubiquitination assays manifested that LINC01426 and USP22 modulated SHH ubiquitination levels. Rescue assays verified that SHH overexpression rescued the cell growth, migration, and stemness suppressed by LINC01426 silencing. In conclusion, LINC01426 promotes LUAD progression by recruiting USP22 to stabilize SHH protein and thus activate the hedgehog pathway.

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