scholarly journals HDAC6 Regulates Radiosensitivity of Non-Small Cell Lung Cancer by Promoting Degradation of Chk1

Cells ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 2237
Author(s):  
Niko Moses ◽  
Mu Zhang ◽  
Jheng-Yu Wu ◽  
Chen Hu ◽  
Shengyan Xiang ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Cell Cycle ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
E3 Ligase ◽  
Small Cell ◽  
Cell Cycle Checkpoint ◽  
Small Cell Lung ◽  
Ubiquitin E3 Ligase

We have previously discovered that HDAC6 regulates the DNA damage response (DDR) via modulating the homeostasis of a DNA mismatch repair protein, MSH2, through HDAC6’s ubiquitin E3 ligase activity. Here, we have reported HDAC6’s second potential E3 ligase substrate, a critical cell cycle checkpoint protein, Chk1. We have found that HDAC6 and Chk1 directly interact, and that HDAC6 ubiquitinates Chk1 in vivo and in vitro. Specifically, HDAC6 interacts with Chk1 via the DAC1 domain, which contains its ubiquitin E3 ligase activity. During the cell cycle, Chk1 protein levels fluctuate, peaking at the G2 phase, subsequently resolving via the ubiquitin-proteasome pathway, and thereby allowing cells to progress to the M phase. However, in HDAC6 knockdown non-small cell lung cancer (NSCLC) cells, Chk1 is constitutively active and fails to resolve post-ionizing radiation (IR), and this enhanced Chk1 activity leads to preferential G2 arrest in HDAC6 knockdown cells accompanied by a reduction in colony formation capacity and viability. Depletion or pharmacological inhibition of Chk1 in HDAC6 knockdown cells reverses this radiosensitive phenotype, suggesting that the radiosensitivity of HDAC6 knockdown cells is dependent on increased Chk1 kinase activity. Overall, our results highlight a novel mechanism of Chk1 regulation at the post-translational level, and a possible strategy for sensitizing NSCLC to radiation via inhibiting HDAC6’s E3 ligase activity.

scholarly journals HDAC6 Regulates Radiosensitivity of Non-Small Cell Lung Cancer by Promoting Degradation of Chk1

2020 ◽  
Author(s):  
Niko Moses ◽  
Mu Zhang ◽  
Jheng-Yu Wu ◽  
Chen Hu ◽  
Shengyan Xiang ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
E3 Ligase ◽  
Radiation Sensitivity ◽  
Small Cell ◽  
Cell Cycle Checkpoint ◽  
Small Cell Lung ◽  
M Phase

ABSTRACTWe previously discovered that HDAC6 regulates the DNA damage response via modulating the homeostasis of a DNA mismatch repair protein, MSH2, through HDAC6’s ubiquitin E3 ligase activity. Here, we have reported HDAC6’s second E3 ligase substrate, a critical cell cycle checkpoint protein, Chk1. We have found that HDAC6 and Chk1 directly interact, and that HDAC6 ubiquitinates Chk1 in vivo. Typical Chk1 protein levels fluctuate, peaking at G2 and subsequently resolving via the ubiquitin-proteasome pathway. However, in HDAC6 knockdown cells, Chk1 is constitutively active and fails to resolve post-ionizing radiation (IR), leading to increased radiation sensitivity. Upon IR treatment, a greater proportion of HDAC6 knockdown cells accumulated at G2/M phase when compared with control cells. Depletion or inhibition of Chk1 in HDAC6 knockdown cells renders those cells radiosensitive, suggesting that persistently high level of Chk1 could lead cells to arrest at G2/M phase and eventually, apoptosis. Clinically, we found that high levels of phosphorylated Chk1 (p-Ser317) are associated with a better overall survival in a cohort of non-small cell lung cancer (NSCLC) patients, suggesting a link between active Chk1 and lung cancer development. Overall, our results highlight a novel mechanism of Chk1 regulation at the protein level, and a possible strategy for sensitizing NSCLC to radiation via inhibiting the activity of HDAC6’s E3 ligase.

scholarly journals MiR-106b-5p Promotes Proliferation and Inhibits Apoptosis by Regulating BTG3 in Non-Small Cell Lung Cancer

2017 ◽  
Vol 44 (4) ◽  
pp. 1545-1558 ◽  
Author(s):  
Ke Wei ◽  
Chunfeng Pan ◽  
Guoliang Yao ◽  
Bin Liu ◽  
Teng Ma ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Cell Cycle ◽  
Small Cell Lung Cancer ◽  
Cell Lines ◽  
Cell Lung Cancer ◽  
Small Cell ◽  
Luciferase Assay ◽  
Small Cell Lung

Background/Aims: MicroRNAs have been validated to play a crucial role in tumorigenesis of non-small cell lung cancer (NSCLC). Although miR-106b-5p has been reported to play a vital role in various malignancies the physiological function of miR-106b-5p in NSCLC still remain unknown. In this study, we investigated the role of miR-106b-5p in NSCLC. Methods: Quantitative real-time polymerase chain reaction was conducted to estimate the expression of miR-106b-5p and BTG3 in both NSCLC tissues and cell lines. The effects of miR-106b-5p on proliferation were determined in vitro using CCK-8 proliferation assays, 5-ethynyl-2’-deoxyuridine (EdU) incorporation, colony formation assays and cell-cycle assays and the in vivo effects were evaluated by a mouse tumorigenicity model. Cell apoptosis and cell cycle was investigated by flow cytometric analysis in vitro. The molecular mechanism underlying the relevance between miR-106b-5p and BTG3 was confirmed by luciferase assay and western blot. Results: In current study, we found a relatively higher miR-106b-5p and lower BTG3 expression in NSCLC specimens and cell lines. BTG3 was verified as a direct target of miR-106b-5p by luciferase assay. In vitro, over-expression of miR-106b-5p promoted proliferation and inhibited apoptosis by down-regulating BTG3 expression. In vivo, miR-106b-5p promoted xenograft tumor formation. Conclusion: Our findings revealed for the first time that miR-106b-5p plays a tumorigenesis role in NSCLC progression by down-regulating BTG3 expression, which may lead to a novel insight to the potential biomarker and novel therapeutic strategies for NSCLC patients.

scholarly journals (−)-Epigallocatechin-3-gallate derivatives combined with cisplatin exhibit synergistic inhibitory effects on non-small-cell lung cancer cells

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Jing Wang ◽  
Peiyuan Sun ◽  
Qi Wang ◽  
Pan Zhang ◽  
Yuna Wang ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Cell Cycle ◽  
Small Cell Lung Cancer ◽  
Cell Lines ◽  
Cell Lung Cancer ◽  
Small Cell ◽  
Egfr Signaling ◽  
Small Cell Lung ◽  
Egfr Signaling Pathway

Abstract Background Non-small-cell lung cancer (NSCLC) is the leading cause of cancer-related death worldwide. The inhibition of epidermal growth factor receptor (EGFR) signaling by tyrosine kinase inhibitors or monoclonal antibodies plays a key role in NSCLC treatment. Unfortunately, these treatment strategies are limited by eventual resistance and cell lines with differential EGFR status. Therefore, new therapeutic strategies for NSCLC are urgently required. Methods To improve the stability and absorption of (−)-epigallocatechin-3-gallate (EGCG), we synthesized a series of EGCG derivatives. The antitumor activities of EGCG derivatives with or without cisplatin were investigated in vitro and vivo. Cell proliferation, cell cycle distribution and apoptosis were measured in NSCLC cell lines and in vivo in a NCI-H441 xenograft model. Results We found that the EGCG derivatives inhibited cell viability and colony formation, caused cell cycle redistribution, and induced apoptosis. More importantly, the combination of the EGCG derivative and cisplatin led to increased growth inhibition, caused cell cycle redistribution, and enhanced the apoptosis rate compared to either compound alone. Consistent with the experiments in vitro, EGCG derivatives plus cisplatin significantly reduced tumor growth. Conclusions The combination treatment was found to inhibit the EGFR signaling pathway and decrease the expression of p-EGFR, p-AKT, and p-ERK in vitro and vivo. Our results suggest that compound 3 is a novel potential compound for NSCLC patients.

scholarly journals Radiosensitization of Non-Small Cell Lung Cancer Cells by the Plk1 Inhibitor Volasertib Is Dependent on the p53 Status

Cancers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1893 ◽  
Author(s):  
Jolien Van den Bossche ◽  
Andreas Domen ◽  
Marc Peeters ◽  
Christophe Deben ◽  
Ines De Pauw ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Cell Cycle ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Apoptotic Cell ◽  
Flow Cytometric Analysis ◽  
Small Cell ◽  
Therapeutic Effects ◽  
Small Cell Lung

Polo-like kinase 1 (Plk1), a master regulator of mitotic cell division, is highly expressed in non-small cell lung cancer (NSCLC) making it an interesting drug target. We examined the in vitro therapeutic effects of volasertib, a Plk1 inhibitor, in combination with irradiation in a panel of NSCLC cell lines with different p53 backgrounds. Pretreatment with volasertib efficiently sensitized p53 wild type cells to irradiation. Flow cytometric analysis revealed that significantly more cells were arrested in the G2/M phase of the cell cycle after the combination therapy compared to either treatment alone (p < 0.005). No significant synergistic induction of apoptotic cell death was observed, but, importantly, significantly more senescent cells were detected when cells were pretreated with volasertib before irradiation compared to both monotherapies alone (p < 0.001), especially in cells with functional p53. Consequently, while most cells with functional p53 showed permanent growth arrest, more p53 knockdown/mutant cells could re-enter the cell cycle, resulting in colony formation and cell survival. Our findings assign functional p53 as a determining factor for the observed radiosensitizing effect of volasertib in combination with radiotherapy for the treatment of NSCLC.

Abstract PR10: Exploiting the G2-M cell cycle checkpoint dependency in small cell lung cancer (SCLC) using pharmacological inhibitors of CHK1 and WEE1

2016 ◽  
Author(s):  
Triparna Sen ◽  
Pan Tong ◽  
Catherine Allison Stewart ◽  
Sandra Cristea ◽  
You Hong-Fan ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Cell Cycle ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Small Cell ◽  
Cell Cycle Checkpoint ◽  
Small Cell Lung ◽  
M Cell ◽  
Cycle Checkpoint

scholarly journals CBIO-01. THERAPEUTIC IMPLICATIONS OF CONDITIONAL VULNERABILITIES CAUSED BY TTFIELDS EXPOSURE IN NOVEL COMBINATION THERAPIES FOR NON-SMALL CELL LUNG CANCER AND BRAIN METASTASES FROM NON-SMALL CELL LUNG CANCER

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii15-ii16
Author(s):  
Narasimha Kumar Karanam ◽  
Michael Story
Keyword(s):  
Lung Cancer ◽  
Cell Cycle ◽  
Dna Repair ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Replication Stress ◽  
Small Cell ◽  
Cell Cycle Checkpoint ◽  
Small Cell Lung ◽  
Cycle Checkpoint

Abstract Tumor Treating Fields (TTFields) are low-intensity, intermediate frequency, alternating electric fields which are FDA-approved for glioblastoma and malignant pleural mesothelioma. Clinical trials are ongoing for other solid tumor cancers, including lung, pancreatic, and ovarian cancers. The initial mechanism for tumor cell killing identified for TTFields exposure was through the disruption of mitosis. Subsequently, it has been shown that TTFields causes replication stress and down-regulates DNA repair and cell cycle checkpoint genes. Here, relative quantitative proteomics were employed to elucidate the cause for the downregulation of DNA repair and cell cycle checkpoint genes. STRING database analysis of differentially expressed proteins revealed interaction networks that included cell cycle, DNA damage repair and replication, and transcriptional and translational regulation. Upstream analysis of key genes associated with cell cycle checkpoint and DNA repair identified reduced expression of the transcriptional activators E2F1 and E2F2 and increased expression of the transcriptional repressor E2F6, suggesting that TTFields affects the CDK–RB–E2F axis. This axis is known to control the transcriptional machinery of the key regulators of cell cycle progression and genome replication fidelity, hence may explain the reduced DNA repair capacity and replication fork maintenance in TTFields-exposed cells. The current study results suggest that TTFields-exposure causes a conditional vulnerability environment that renders cells more susceptible to chemotherapeutic agents that block interfere with the E2F-RB-CDK4/6 axis, inducing DNA damage and replication stress. TTFields-exposure synergistically enhanced the efficacy of the E2F inhibitor HLM006474 with or without the CDK4/6 inhibitor abemaciclib. TTFields plus either or combination of cisplatin and etoposide (known enhancers of replication stress) synergistically enhanced cell killing. These results suggest that the combination of cisplatin and etoposide together with TTFields would be beneficial for non-small cell lung cancer patients and patients with brain metastases from non-small cell lung cancer.

Investigation of in vitro Activities of Cu2ZnSnS4 Nanoparticles in Human Non-Small Cell Lung Cancer

2021 ◽  
pp. 102304
Author(s):  
Suleyman Gokhan Colak ◽  
Canan Vejselova Sezer ◽  
Ruken Esra Demirdogen ◽  
Mine Ince ◽  
Fatih Mehmet Emen ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Small Cell ◽  
Small Cell Lung

scholarly journals Elevating CDCA3 levels in non-small cell lung cancer enhances sensitivity to platinum-based chemotherapy

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Katrina Kildey ◽  
Neha S. Gandhi ◽  
Katherine B. Sahin ◽  
Esha T. Shah ◽  
Eric Boittier ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Genome Instability ◽  
Small Cell ◽  
Small Cell Lung ◽  
Protein Levels ◽  
Platinum Based Chemotherapy ◽  
Platinum Agents

AbstractPlatinum-based chemotherapy remains the cornerstone of treatment for most non-small cell lung cancer (NSCLC) cases either as maintenance therapy or in combination with immunotherapy. However, resistance remains a primary issue. Our findings point to the possibility of exploiting levels of cell division cycle associated protein-3 (CDCA3) to improve response of NSCLC tumours to therapy. We demonstrate that in patients and in vitro analyses, CDCA3 levels correlate with measures of genome instability and platinum sensitivity, whereby CDCA3high tumours are sensitive to cisplatin and carboplatin. In NSCLC, CDCA3 protein levels are regulated by the ubiquitin ligase APC/C and cofactor Cdh1. Here, we identified that the degradation of CDCA3 is modulated by activity of casein kinase 2 (CK2) which promotes an interaction between CDCA3 and Cdh1. Supporting this, pharmacological inhibition of CK2 with CX-4945 disrupts CDCA3 degradation, elevating CDCA3 levels and increasing sensitivity to platinum agents. We propose that combining CK2 inhibitors with platinum-based chemotherapy could enhance platinum efficacy in CDCA3low NSCLC tumours and benefit patients.

Inhibition of yes-associated protein suppresses migration, invasion, and metastasis in non-small cell lung cancer in vitro and in vivo

2021 ◽  
Author(s):  
Tomoya Takeda ◽  
Masanobu Tsubaki ◽  
Shuji Genno ◽  
Takuya Matsuda ◽  
Yuuta Yamamoto ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Small Cell ◽  
Invasion And Metastasis ◽  
Small Cell Lung

scholarly journals Mimicking Tumor Hypoxia in Non-Small Cell Lung Cancer Employing Three-Dimensional In Vitro Models

Cells ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 141
Author(s):  
Iwona Ziółkowska-Suchanek
Keyword(s):  
Lung Cancer ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Tumor Hypoxia ◽  
Three Dimensional ◽  
In Vitro Models ◽  
Small Cell ◽  
Small Cell Lung ◽  
Multicellular Tumor Spheroid

Hypoxia is the most common microenvironment feature of lung cancer tumors, which affects cancer progression, metastasis and metabolism. Oxygen induces both proteomic and genomic changes within tumor cells, which cause many alternations in the tumor microenvironment (TME). This review defines current knowledge in the field of tumor hypoxia in non-small cell lung cancer (NSCLC), including biology, biomarkers, in vitro and in vivo studies and also hypoxia imaging and detection. While classic two-dimensional (2D) in vitro research models reveal some hypoxia dependent manifestations, three-dimensional (3D) cell culture models more accurately replicate the hypoxic TME. In this study, a systematic review of the current NSCLC 3D models that have been able to mimic the hypoxic TME is presented. The multicellular tumor spheroid, organoids, scaffolds, microfluidic devices and 3D bioprinting currently being utilized in NSCLC hypoxia studies are reviewed. Additionally, the utilization of 3D in vitro models for exploring biological and therapeutic parameters in the future is described.

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