Long non-coding RNA CASC9 promotes gefitinib resistance in NSCLC by epigenetic repression of DUSP1

Abstract Resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), such as gefitinib, has greatly affected clinical outcomes in non-small cell lung cancer (NSCLC) patients. The long noncoding RNAs (lncRNAs) are known to regulate tumorigenesis and cancer progression, but their contributions to NSCLC gefitinib resistance remain poorly understood. In this study, by analyzing the differentially expressed lncRNAs in gefitinib-resistant cells and gefitinib-sensitive cells in the National Institute of Health GEO dataset, we found that lncRNA CASC9 expression was upregulated, and this was also verified in resistant tissues. Gain and loss of function studies showed that CASC9 inhibition restored gefitinib sensitivity both in vitro and in vivo, whereas CASC9 overexpression promoted gefitinib resistance. Mechanistically, CASC9 repressed the tumor suppressor DUSP1 by recruiting histone methyltransferase EZH2, thereby increasing the resistance to gefitinib. Furthermore, ectopic expression of DUSP1 increased gefitinib sensitivity by inactivating the ERK pathway. Our results highlight the essential role of CASC9 in gefitinib resistance, suggesting that the CASC9/EZH2/DUSP1 axis might be a novel target for overcoming EGFR-TKI resistance in NSCLC.

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PKCδ-mediated SGLT1 upregulation confers the acquired resistance of NSCLC to EGFR TKIs

Oncogene ◽

10.1038/s41388-021-01889-0 ◽

2021 ◽

Author(s):

Chia-Hung Chen ◽

Bo-Wei Wang ◽

Yu-Chun Hsiao ◽

Chun-Yi Wu ◽

Fang-Ju Cheng ◽

...

Keyword(s):

Glucose Uptake ◽

Kinase Inhibitors ◽

Acquired Resistance ◽

Growth Factor Receptor ◽

Tki Treatment ◽

Nsclc Patients ◽

Egfr Tki ◽

Egfr Tkis

AbstractThe tyrosine kinase inhibitors (TKIs) targeting epidermal growth factor receptor (EGFR) have been widely used for non-small cell lung cancer (NSCLC) patients, but the development of acquired resistance remains a therapeutic hurdle. The reduction of glucose uptake has been implicated in the anti-tumor activity of EGFR TKIs. In this study, the upregulation of the active sodium/glucose co-transporter 1 (SGLT1) was found to confer the development of acquired EGFR TKI resistance and was correlated with the poorer clinical outcome of the NSCLC patients who received EGFR TKI treatment. Blockade of SGLT1 overcame this resistance in vitro and in vivo by reducing glucose uptake in NSCLC cells. Mechanistically, SGLT1 protein was stabilized through the interaction with PKCδ-phosphorylated (Thr678) EGFR in the TKI-resistant cells. Our findings revealed that PKCδ/EGFR axis-dependent SGLT1 upregulation was a critical mechanism underlying the acquired resistance to EGFR TKIs. We suggest co-targeting PKCδ/SGLT1 as a potential strategy to improve the therapeutic efficacy of EGFR TKIs in NSCLC patients.

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

Cell Death and Disease ◽

10.1038/s41419-020-03316-w ◽

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.

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Rare variants in KDR, encoding VEGF Receptor 2, are associated with tetralogy of Fallot

Genetics in Medicine ◽

10.1038/s41436-021-01212-y ◽

2021 ◽

Author(s):

Doris Škorić-Milosavljević ◽

Najim Lahrouchi ◽

Fernanda M. Bosada ◽

Gregor Dombrowsky ◽

Simon G. Williams ◽

...

Keyword(s):

Exome Sequencing ◽

Tetralogy Of Fallot ◽

Large Scale ◽

Rare Variants ◽

Growth Factor Receptor ◽

Vegf Receptor ◽

Loss Of Function ◽

Endothelial Growth Factor

Abstract Purpose Rare genetic variants in KDR, encoding the vascular endothelial growth factor receptor 2 (VEGFR2), have been reported in patients with tetralogy of Fallot (TOF). However, their role in disease causality and pathogenesis remains unclear. Methods We conducted exome sequencing in a familial case of TOF and large-scale genetic studies, including burden testing, in >1,500 patients with TOF. We studied gene-targeted mice and conducted cell-based assays to explore the role of KDR genetic variation in the etiology of TOF. Results Exome sequencing in a family with two siblings affected by TOF revealed biallelic missense variants in KDR. Studies in knock-in mice and in HEK 293T cells identified embryonic lethality for one variant when occurring in the homozygous state, and a significantly reduced VEGFR2 phosphorylation for both variants. Rare variant burden analysis conducted in a set of 1,569 patients of European descent with TOF identified a 46-fold enrichment of protein-truncating variants (PTVs) in TOF cases compared to controls (P = 7 × 10-11). Conclusion Rare KDR variants, in particular PTVs, strongly associate with TOF, likely in the setting of different inheritance patterns. Supported by genetic and in vivo and in vitro functional analysis, we propose loss-of-function of VEGFR2 as one of the mechanisms involved in the pathogenesis of TOF.

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Spironolactone, a Classic Potassium-Sparing Diuretic, Reduces Survivin Expression and Chemosensitizes Cancer Cells to Non-DNA-Damaging Anticancer Drugs

Cancers ◽

10.3390/cancers11101550 ◽

2019 ◽

Vol 11 (10) ◽

pp. 1550 ◽

Cited By ~ 2

Author(s):

Tomomi Sanomachi ◽

Shuhei Suzuki ◽

Keita Togashi ◽

Asuka Sugai ◽

Shizuka Seino ◽

...

Keyword(s):

Cancer Cells ◽

Kinase Inhibitors ◽

Xenograft Model ◽

Growth Factor Receptor ◽

Survivin Expression ◽

Mouse Xenograft Model ◽

Anti Cancer ◽

Underlying Mechanisms

Spironolactone, a classical diuretic drug, is used to treat tumor-associated complications in cancer patients. Spironolactone was recently reported to exert anti-cancer effects by suppressing DNA damage repair. However, it currently remains unclear whether spironolactone exerts combinational effects with non-DNA-damaging anti-cancer drugs, such as gemcitabine and epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). Using the cancer cells of lung cancer, pancreatic cancer, and glioblastoma, the combinational effects of spironolactone with gemcitabine and osimertinib, a third-generation EGFR-TKI, were examined in vitro with cell viability assays. To elucidate the underlying mechanisms, we investigated alterations induced in survivin, an anti-apoptotic protein, by spironolactone as well as the chemosensitization effects of the suppression of survivin by YM155, an inhibitor of survivin, and siRNA. We also examined the combinational effects in a mouse xenograft model. The results obtained revealed that spironolactone augmented cell death and the suppression of cell growth by gemcitabine and osimertinib. Spironolactone also reduced the expression of survivin in these cells, and the pharmacological and genetic suppression of survivin sensitized cells to gemcitabine and osimertinib. This combination also significantly suppressed tumor growth without apparent adverse effects in vivo. In conclusion, spironolactone is a safe candidate drug that exerts anti-cancer effects in combination with non-DNA-damaging drugs, such as gemcitabine and osimertinib, most likely through the suppression of survivin.

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Macroautophagy is dispensable for growth of KRAS mutant tumors and chloroquine efficacy

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1515617113 ◽

2015 ◽

Vol 113 (1) ◽

pp. 182-187 ◽

Cited By ~ 124

Author(s):

Christina H. Eng ◽

Zuncai Wang ◽

Diane Tkach ◽

Lourdes Toral-Barza ◽

Savuth Ugwonali ◽

...

Keyword(s):

Anticancer Agents ◽

Kinase Inhibitors ◽

Cell Types ◽

Loss Of Function ◽

Growth And Survival ◽

Oncogenic Mutations ◽

Cellular Context ◽

Genetic Stratification

Macroautophagy is a key stress-response pathway that can suppress or promote tumorigenesis depending on the cellular context. Notably, Kirsten rat sarcoma (KRAS)-driven tumors have been reported to rely on macroautophagy for growth and survival, suggesting a potential therapeutic approach of using autophagy inhibitors based on genetic stratification. In this study, we evaluated whether KRAS mutation status can predict the efficacy to macroautophagy inhibition. By profiling 47 cell lines with pharmacological and genetic loss-of-function tools, we were unable to confirm that KRAS-driven tumor lines require macroautophagy for growth. Deletion of autophagy-related 7 (ATG7) by genome editing completely blocked macroautophagy in several tumor lines with oncogenic mutations in KRAS but did not inhibit cell proliferation in vitro or tumorigenesis in vivo. Furthermore, ATG7 knockout did not sensitize cells to irradiation or to several anticancer agents tested. Interestingly, ATG7-deficient and -proficient cells were equally sensitive to the antiproliferative effect of chloroquine, a lysosomotropic agent often used as a pharmacological tool to evaluate the response to macroautophagy inhibition. Moreover, both cell types manifested synergistic growth inhibition when treated with chloroquine plus the tyrosine kinase inhibitors erlotinib or sunitinib, suggesting that the antiproliferative effects of chloroquine are independent of its suppressive actions on autophagy.

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Role of PARP1-mediated autophagy in EGFR-TKI resistance in non-small cell lung cancer

Scientific Reports ◽

10.1038/s41598-020-77908-z ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Zhimin Zhang ◽

Xiaojuan Lian ◽

Wei Xie ◽

Jin Quan ◽

Maojun Liao ◽

...

Keyword(s):

Lung Cancer ◽

Kinase Inhibitors ◽

Growth Factor Receptor ◽

Advanced Lung Cancer ◽

Tki Resistance ◽

Geo Dataset ◽

Epidermal Growth

AbstractResistance to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) has become the main clinical challenge of advanced lung cancer. This research aimed to explore the role of PARP1-mediated autophagy in the progression of TKI therapy. PARP1-mediated autophagy was evaluated in vitro by CCK-8 assay, clonogenic assay, immunofluorescence, and western blot in the HCC-827, H1975, and H1299 cells treated with icotinib (Ico), rapamycin, and AZD2281 (olaparib) alone or in combination. Our results and GEO dataset analysis confirmed that PARP1 is expressed at lower levels in TKI-sensitive cells than in TKI-resistant cells. Low PARP1 expression and high p62 expression were associated with good outcomes among patients with NSCLC after TKI therapy. AZD2281 and a lysosomal inhibitor reversed resistance to Ico by decreasing PARP1 and LC3 in cells, but an mTOR inhibitor did not decrease Ico resistance. The combination of AZD2281 and Ico exerted a markedly enhanced antitumor effect by reducing PARP1 expression and autophagy in vivo. Knockdown of PARP1 expression reversed the resistance to TKI by the mTOR/Akt/autophagy pathway in HCC-827IR, H1975, and H1299 cells. PARP1-mediated autophagy is a key pathway for TKI resistance in NSCLC cells that participates in the resistance to TKIs. Olaparib may serve as a novel method to overcome the resistance to TKIs.

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miR551b Regulates Colorectal Cancer Progression by Targeting the ZEB1 Signaling Axis

Cancers ◽

10.3390/cancers11050735 ◽

2019 ◽

Vol 11 (5) ◽

pp. 735 ◽

Cited By ~ 2

Author(s):

Kwang Seock Kim ◽

Dongjun Jeong ◽

Ita Novita Sari ◽

Yoseph Toni Wijaya ◽

Nayoung Jun ◽

...

Keyword(s):

Colorectal Cancer ◽

Cell Lines ◽

Cancer Progression ◽

Epithelial Mesenchymal Transition ◽

Ectopic Expression ◽

Xenograft Model ◽

Mesenchymal Transition ◽

Normal Tissues

Our current understanding of the role of microRNA 551b (miR551b) in the progression of colorectal cancer (CRC) remains limited. Here, studies using both ectopic expression of miR551b and miR551b mimics revealed that miR551b exerts a tumor suppressive effect in CRC cells. Specifically, miR551b was significantly downregulated in both patient-derived CRC tissues and CRC cell lines compared to normal tissues and non-cancer cell lines. Also, miR551b significantly inhibited the motility of CRC cells in vitro, including migration, invasion, and wound healing rates, but did not affect cell proliferation. Mechanistically, miR551b targets and inhibits the expression of ZEB1 (Zinc finger E-box-binding homeobox 1), resulting in the dysregulation of EMT (epithelial-mesenchymal transition) signatures. More importantly, miR551b overexpression was found to reduce the tumor size in a xenograft model of CRC cells in vivo. Furthermore, bioinformatic analyses showed that miR551b expression levels were markedly downregulated in the advanced-stage CRC tissues compared to normal tissues, and ZEB1 was associated with the disease progression in CRC patients. Our findings indicated that miR551b could serve as a potential diagnostic biomarker and could be utilized to improve the therapeutic outcomes of CRC patients.

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c-Src Associates with ErbB2 through an Interaction between Catalytic Domains and Confers Enhanced Transforming Potential

Molecular and Cellular Biology ◽

10.1128/mcb.01731-08 ◽

2009 ◽

Vol 29 (21) ◽

pp. 5858-5871 ◽

Cited By ~ 42

Author(s):

Richard Marcotte ◽

Lixin Zhou ◽

Harold Kim ◽

Calvin D. Roskelly ◽

William J. Muller

Keyword(s):

Kinase Inhibitors ◽

Catalytic Domain ◽

Growth Factor Receptor ◽

Src Tyrosine Kinase ◽

Increased Sensitivity ◽

Epidermal Growth ◽

Egfr Family ◽

Egfr Mutant

ABSTRACT Previous studies have demonstrated that c-Src tyrosine kinase interacts specifically with ErbB2, but not with other members of the epidermal growth factor receptor (EGFR) family. To identify the site of interaction, we recently used a chimeric EGFR/ErbB2 receptor approach to show that c-Src requires the kinase region of ErbB2 for binding. Here, we demonstrate that retention of a conserved amino acid motif surrounding tyrosine 877 (referred to here as EGFRYHAD) is sufficient to confer binding to c-Src. Surprisingly the association of c-Src was not dependent on its SH2 or SH3 domain or on the phosphorylation or kinase activity of the receptor. We further show that the chimeric EGFRs that contain the Y877 motif are transforming in vitro and in vivo following ligand stimulation. Transformation was also partially dependent on sustained activation of Stat3. Finally, we demonstrate that EGFRs with mutations in the catalytic domain, originally identified in lung cancer and conferring increased sensitivity to gefitinib and erlotinib, two EGFR kinase inhibitors, gained the capacity to bind c-Src. Moreover, transformation by these EGFR mutants was inhibited by Src inhibitors regardless of their sensitivities to gefitinib and erlotinib. These observations have important implications for understanding the molecular basis for resistance to EGFR inhibitors and implicate c-Src as a critical signaling molecule in EGFR mutant-induced transformation.

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A Positive Feedback Loop of lncRNA MIR31HG-miR-361-3p -YY1 Accelerates Colorectal Cancer Progression Through Modulating Proliferation, Angiogenesis, and Glycolysis

Frontiers in Oncology ◽

10.3389/fonc.2021.684984 ◽

2021 ◽

Vol 11 ◽

Author(s):

Tao Guo ◽

Defeng Liu ◽

Shihao Peng ◽

Meng Wang ◽

Yangyang Li

Keyword(s):

Colorectal Cancer ◽

Cancer Progression ◽

Positive Feedback ◽

Feedback Loop ◽

Luciferase Reporter ◽

Loss Of Function ◽

Positive Feedback Loop ◽

Related Proteins

BackgroundColorectal cancer (CRC) is a common malignant tumor with high metastatic and recurrent rates. This study probes the effect and mechanism of long non-coding RNA MIR31HG on the progression of CRC cells.Materials and MethodsQuantitative real-time PCR (qRT-PCR) was used to analyze the expression of MIR31HG and miR-361-3p in CRC tissues and normal tissues. Gain- or loss-of-function assays were conducted to examine the roles of MIR31HG, miR-361-3p and YY1 transcription factor (YY1) in the CRC progression. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and colony formation experiment were conducted to test CRC cell proliferation. CRC cell invasion was determined by Transwell assay. The glucose detection kit and lactic acid detection kit were utilized to monitor the levels of glucose and lactate in CRC cells. The glycolysis level in CRC cells was examined by the glycolytic stress experiment. Western blot was performed to compare the expression of glycolysis-related proteins (PKM2, GLUT1 and HK2) and angiogenesis-related proteins (including VEGFA, ANGPT1, HIF1A and TIMP1) in HUVECs. The binding relationships between MIR31HG and miR-361-3p, miR-361-3p and YY1 were evaluated by the dual-luciferase reporter assay and RNA immunoprecipitation (RIP).ResultsMIR31HG was up-regulated in CRC tissues and was associated with poorer prognosis of CRC patients. The in-vitro and in-vivo experiments confirmed that overexpressing MIR31HG heightened the proliferation, growth, invasion, glycolysis and lung metastasis of CRC cells as well as the angiogenesis of HUVECs. In addition, MIR3HG overexpression promoted YY1 mRNA and protein level, and forced overexpression of YY1 enhanced MIR31HG level. Overexpressing YY1 reversed the tumor-suppressive effect mediated by MIR31HG knockdown. miR-361-3p, which was inhibited by MIR31HG overexpression, repressed the malignant behaviors of CRC cells. miR-361-3p-mediated anti-tumor effects were mostly reversed by upregulating MIR31HG. Further mechanism studies illustrated that miR-361-3p targeted and negatively regulated the expression of YY1.ConclusionThis study reveals that MIR31HG functions as an oncogenic gene in CRC via forming a positive feedback loop of MIR31HG-miR-361-3p-YY1.

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Linc00473 potentiates cholangiocarcinoma progression by modulation of DDX5 expression via miR-506 regulation

10.21203/rs.3.rs-25881/v2 ◽

2020 ◽

Author(s):

Lining Huang ◽

Xingming Jiang ◽

Zhenglong Li ◽

Jinglin Li ◽

Xuan Lin ◽

...

Keyword(s):

Cell Lines ◽

Cancer Progression ◽

Luciferase Reporter ◽

Loss Of Function ◽

Qrt Pcr ◽

Competitive Endogenous Rnas ◽

Rna Immunoprecipitation ◽

Underlying Mechanisms

Abstract Background: Cholangiocarcinoma (CCA) is a mortal cancer with high mortality, whereas the function and mechanism of occurrence and progression of CCA are still mysterious. Long non-coding RNAs (lncRNAs) could function as important regulators in carcinogenesis and cancer progression. Growing evidences have indicated that the novel lncRNA linc00473 plays an important role in cancer progression and metastasis. However, its function and molecular mechanism in CCA remain unknown. Methods: The linc00473 expression in CCA tissues and cell lines was analyzed using qRT-PCR. Gain- and loss-of-function experiments were conducted to investigate the biological functions of linc00473 both in vitro and in vivo. Insights into the underlying mechanisms of competitive endogenous RNAs (ceRNAs) were determined by bioinformatics analysis, dual-luciferase reporter assays, qRT-PCR arrays, RNA immunoprecipitation (RIP) and rescue experiments. Results: Linc00473 was highly expressed in CCA tissues and cell lines. Linc00473 knockdown inhibited CCA growth and metastasis. Furthermore, linc00473 acted as miR-506 sponge and regulated its target gene DDX5 expression. Rescue assays verified that linc00473 modulated the tumorigenesis of CCA by regulating miR-506. Conclusions: The data indicated that linc00473 played an oncogenic role in CCA growth and metastasis, and could serve as a novel molecular target for treating CCA.

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