scholarly journals Coibamide A Targets Sec61 to Prevent Biogenesis of Secretory and Membrane Proteins

2019 ◽  
Author(s):  
Dale Tranter ◽  
Anja Paatero ◽  
Shinsaku Kawaguchi ◽  
Soheila Kazemi ◽  
Jeffrey D. Serrill ◽  
...  
Keyword(s):  
Cancer Cell ◽  
Protein Import ◽  
Human Cancer ◽  
Binding Mode ◽  
Marine Natural Product ◽  
Resistance Mutations ◽  
Human Cancer Cells ◽  
Channel Inhibition ◽  
Coibamide A ◽  
Nci60 Panel

Coibamide A (CbA) is a marine natural product with potent antiproliferative activity against human cancer cells and a unique selectivity profile. Despite promising antitumor activity, the mechanism of cytotoxicity and specific cellular target remain unknown. Here, we develop an optimized synthetic CbA photoaffinity probe (photo-CbA) and use it to demonstrate that CbA directly targets the Sec61α subunit of the trimeric Sec61 translocon. CbA binding to Sec61 results in broad substrate-nonselective inhibition of ER protein import and potent cytotoxicity against specific cancer cell lines. CbA targets a lumenal cavity of Sec61α that is partially shared with known Sec61 inhibitors, yet profiling against resistance conferring Sec61α mutations identified from human HCT116 cells suggests a distinct binding mode for CbA. Specifically, despite conferring strong resistance to all previously known Sec61 inhibitors, the Sec61α mutant R66I remains sensitive to CbA. A further unbiased screen for Sec61α resistance mutations identified the CbA-resistant mutation S71P, which confirms non-identical binding sites for CbA and apratoxin A and supports the susceptibility of the Sec61 plug region for channel inhibition. Remarkably, CbA, apratoxin A andipomoeassin F do not display comparable patterns of potency and selectivity in the NCI60 panel of human cancer cell lines.Our work connecting CbA activity with selective prevention of secretory and membrane protein biogenesis by inhibition of Sec61 opens up possibilities for developing new Sec61 inhibitors with improved drug-like properties that are based on the coibamide pharmacophore.

scholarly journals Coibamide A Targets Sec61 to Prevent Biogenesis of Secretory and Membrane Proteins

2019 ◽  
Author(s):  
Dale Tranter ◽  
Anja Paatero ◽  
Shinsaku Kawaguchi ◽  
Soheila Kazemi ◽  
Jeffrey D. Serrill ◽  
...  
Keyword(s):  
Cancer Cell ◽  
Protein Import ◽  
Human Cancer ◽  
Binding Mode ◽  
Marine Natural Product ◽  
Resistance Mutations ◽  
Human Cancer Cells ◽  
Channel Inhibition ◽  
Coibamide A ◽  
Nci60 Panel

Coibamide A (CbA) is a marine natural product with potent antiproliferative activity against human cancer cells and a unique selectivity profile. Despite promising antitumor activity, the mechanism of cytotoxicity and specific cellular target remain unknown. Here, we develop an optimized synthetic CbA photoaffinity probe (photo-CbA) and use it to demonstrate that CbA directly targets the Sec61α subunit of the trimeric Sec61 translocon. CbA binding to Sec61 results in broad substrate-nonselective inhibition of ER protein import and potent cytotoxicity against specific cancer cell lines. CbA targets a lumenal cavity of Sec61α that is partially shared with known Sec61 inhibitors, yet profiling against resistance conferring Sec61α mutations identified from human HCT116 cells suggests a distinct binding mode for CbA. Specifically, despite conferring strong resistance to all previously known Sec61 inhibitors, the Sec61α mutant R66I remains sensitive to CbA. A further unbiased screen for Sec61α resistance mutations identified the CbA-resistant mutation S71P, which confirms non-identical binding sites for CbA and apratoxin A and supports the susceptibility of the Sec61 plug region for channel inhibition. Remarkably, CbA, apratoxin A andipomoeassin F do not display comparable patterns of potency and selectivity in the NCI60 panel of human cancer cell lines.Our work connecting CbA activity with selective prevention of secretory and membrane protein biogenesis by inhibition of Sec61 opens up possibilities for developing new Sec61 inhibitors with improved drug-like properties that are based on the coibamide pharmacophore.

scholarly journals Secretoglobin 3A2 eliminates human cancer cells through pyroptosis

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Shigetoshi Yokoyama ◽  
Shun Nakayama ◽  
Lei Xu ◽  
Aprile L. Pilon ◽  
Shioko Kimura
Keyword(s):  
Cancer Cells ◽  
Cell Lines ◽  
Cancer Cell ◽  
Human Cancer ◽  
Cancer Cell Lines ◽  
Innate Immune ◽  
Innate Immune Cells ◽  
Lung Cancer Cell ◽  
Small Cell Lung ◽  
Human Cancer Cells

AbstractNon-canonical inflammasome activation that recognizes intracellular lipopolysaccharide (LPS) causes pyroptosis, the inflammatory death of innate immune cells. The role of pyroptosis in innate immune cells is to rapidly eliminate pathogen-infected cells and limit the replication niche in the host body. Whether this rapid cell elimination process of pyroptosis plays a role in elimination of cancer cells is largely unknown. Our earlier study demonstrated that a multi-functional secreted protein, secretoglobin (SCGB) 3A2, chaperones LPS to cytosol, and activates caspase-11 and the non-canonical inflammasome pathway, leading to pyroptosis. Here we show that SCGB3A2 exhibits marked anti-cancer activity against 5 out of 11 of human non-small cell lung cancer cell lines in mouse xenographs, while no effect was observed in 6 of 6 small cell lung cancer cell lines examined. All SCGB3A2-LPS-sensitive cells express syndecan 1 (SDC1), a SCGB3A2 cell surface receptor, and caspase-4 (CASP4), a critical component of the non-canonical inflammasome pathway. Two epithelial-derived colon cancer cell lines expressing SDC1 and CASP4 were also susceptible to SCGB3A2-LPS treatment. TCGA analysis revealed that lung adenocarcinoma patients with higher SCGB3A2 mRNA levels exhibited better survival. These data suggest that SCGB3A2 uses the machinery of pyroptosis for the elimination of human cancer cells via the non-canonical inflammasome pathway, and that SCGB3A2 may serve as a novel therapeutic to treat cancer, perhaps in combination with immuno and/or targeted therapies.

scholarly journals Chimeric antigen receptors that trigger phagocytosis

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Meghan A Morrissey ◽  
Adam P Williamson ◽  
Adriana M Steinbach ◽  
Edward W Roberts ◽  
Nadja Kern ◽  
...  
Keyword(s):  
Cancer Cells ◽  
Cancer Cell ◽  
Immune Cell ◽  
Human Cancer ◽  
Antibody Fragment ◽  
Cell Number ◽  
Antigen Receptors ◽  
Chimeric Antigen Receptors ◽  
Cell Therapies ◽  
Human Cancer Cells

Chimeric antigen receptors (CARs) are synthetic receptors that reprogram T cells to kill cancer. The success of CAR-T cell therapies highlights the promise of programmed immunity and suggests that applying CAR strategies to other immune cell lineages may be beneficial. Here, we engineered a family of Chimeric Antigen Receptors for Phagocytosis (CAR-Ps) that direct macrophages to engulf specific targets, including cancer cells. CAR-Ps consist of an extracellular antibody fragment, which can be modified to direct CAR-P activity towards specific antigens. By screening a panel of engulfment receptor intracellular domains, we found that the cytosolic domains from Megf10 and FcRɣ robustly triggered engulfment independently of their native extracellular domain. We show that CAR-Ps drive specific engulfment of antigen-coated synthetic particles and whole human cancer cells. Addition of a tandem PI3K recruitment domain increased cancer cell engulfment. Finally, we show that CAR-P expressing murine macrophages reduce cancer cell number in co-culture by over 40%.

scholarly journals T-cell co-stimulation in combination with targeting FAK drives enhanced anti-tumor immunity

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Marta Canel ◽  
David Taggart ◽  
Andrew H Sims ◽  
David W Lonergan ◽  
Irene C Waizenegger ◽  
...  
Keyword(s):  
T Cell ◽  
Cancer Cell ◽  
Tumor Immunity ◽  
Checkpoint Inhibitors ◽  
Human Cancer ◽  
Complete Regression ◽  
Murine Tumors ◽  
Epithelial Cancers ◽  
Human Cancer Cells ◽  
Cell Expression

Focal Adhesion Kinase (FAK) inhibitors are currently undergoing clinical testing in combination with anti-PD-1 immune checkpoint inhibitors. However, which patients are most likely to benefit from FAK inhibitors, and what the optimal FAK/immunotherapy combinations are, is currently unknown. We identify that cancer cell expression of the T-cell co-stimulatory ligand CD80 sensitizes murine tumors to a FAK inhibitor and show that CD80 is expressed by human cancer cells originating from both solid epithelial cancers and some hematological malignancies in which FAK inhibitors have not been tested clinically. In the absence of CD80, we identify that targeting alternative T-cell co-stimulatory receptors, in particular OX-40 and 4-1BB in combination with FAK, can drive enhanced anti-tumor immunity and even complete regression of murine tumors. Our findings provide rationale supporting the clinical development of FAK inhibitors in combination with patient selection based on cancer cell CD80 expression, and alternatively with therapies targeting T-cell co-stimulatory pathways.

scholarly journals Deficiency of Ku Induces Host Cell Exploitation in Human Cancer Cells

2021 ◽  
Vol 9 ◽  
Author(s):  
Okay Saydam ◽  
Nurten Saydam
Keyword(s):  
Host Cell ◽  
Cancer Cells ◽  
Cell Line ◽  
Cancer Cell ◽  
Cancer Metastasis ◽  
Human Cancer ◽  
Therapy Resistance ◽  
Host Cells ◽  
Human Cancer Cells ◽  
Parasitic Lifestyle

Cancer metastasis is the major cause of death from cancer (Massague and Obenauf, 2016; Steeg, 2016). The extensive genetic heterogeneity and cellular plasticity of metastatic tumors set a prime barrier for the current cancer treatment protocols (Boumahdi and de Sauvage, 2020). In addition, acquired therapy resistance has become an insurmountable obstacle that abolishes the beneficial effects of numerous anti-cancer regimens (De Angelis et al., 2019; Boumahdi and de Sauvage, 2020). Here we report that deficiency of Ku leads to the exploitation of host cells in human cancer cell line models. We found that, upon conditional deletion of XRCC6 that codes for Ku70, HCT116 human colorectal cancer cells gain a parasitic lifestyle that is characterized by the continuous cycle of host cell exploitation. We also found that DAOY cells, a human medulloblastoma cell line, innately lack nuclear Ku70/Ku86 proteins and utilize the host-cell invasion/exit mechanism for maintenance of their survival, similarly to the Ku70 conditionally-null HCT116 cells. Our study demonstrates that a functional loss of Ku protein promotes an adaptive, opportunistic switch to a parasitic lifestyle in human cancer cells, providing evidence for a previously unknown mechanism of cell survival in response to severe genomic stress. We anticipate that our study will bring a new perspective for understanding the mechanisms of cancer cell evolution, leading to a shift in the current concepts of cancer therapy protocols directed to the prevention of cancer metastasis and therapy resistance.

scholarly journals System-Wide Analysis of Protein Acetylation and Ubiquitination Reveals a Diversified Regulation in Human Cancer Cells

Biomolecules ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 411 ◽  
Author(s):  
Hiroko Kozuka-Hata ◽  
Aya Kitamura ◽  
Tomoko Hiroki ◽  
Aiko Aizawa ◽  
Kouhei Tsumoto ◽  
...  
Keyword(s):  
Cancer Cells ◽  
Cancer Cell ◽  
Translational Control ◽  
Large Scale ◽  
Human Cancer ◽  
Initiation Factor ◽  
Protein Acetylation ◽  
Human Cancer Cell Lines ◽  
Human Cancer Cells ◽  
Lysine Modification

Post-translational modifications are known to be widely involved in the regulation of various biological processes, through the extensive diversification of each protein function at the cellular network level. In order to unveil the system-wide function of the protein lysine modification in cancer cell signaling, we performed global acetylation and ubiquitination proteome analyses of human cancer cells, based on high-resolution nanoflow liquid chromatography–tandem mass spectrometry, in combination with the efficient biochemical enrichment of target modified peptides. Our large-scale proteomic analysis enabled us to identify more than 5000 kinds of ubiquitinated sites and 1600 kinds of acetylated sites, from representative human cancer cell lines, leading to the identification of approximately 900 novel lysine modification sites in total. Very interestingly, 236 lysine residues derived from 141 proteins were found to be modified with both ubiquitination and acetylation. As a consequence of the subsequent motif extraction analyses, glutamic acid (E) was found to be highly enriched at the position (−1) for the lysine acetylation sites, whereas the same amino acid was relatively dispersed along the neighboring residues of the lysine ubiquitination sites. Our pathway analysis also indicated that the protein translational control pathways, such as the eukaryotic initiation factor 2 (EIF2) and the ubiquitin signaling pathways, were highly enriched in both of the acetylation and ubiquitination proteome data at the network level. This report provides the first integrative description of the protein acetylation and ubiquitination-oriented systematic regulation in human cancer cells.

scholarly journals Pharmacological Targeting of STING-Dependent IL-6 Production in Cancer Cells

2022 ◽  
Vol 9 ◽  
Author(s):  
Sumaiah S. Al-Asmari ◽  
Aleksandra Rajapakse ◽  
Tomalika R. Ullah ◽  
Geneviève Pépin ◽  
Laura V. Croft ◽  
...  
Keyword(s):  
Dna Damage ◽  
Cancer Cells ◽  
Colony Formation ◽  
Human Cancer ◽  
Type I ◽  
Type I Ifn ◽  
Human Cancer Cells ◽  
Rapid Production ◽  
Nci60 Panel ◽  
Sting Pathway

Activation of the STING pathway upon genotoxic treatment of cancer cells has been shown to lead to anti-tumoral effects, mediated through the acute production of interferon (IFN)-β. Conversely, the pathway also correlates with the expression of NF-κB-driven pro-tumorigenic genes, but these associations are only poorly defined in the context of genotoxic treatment, and are thought to correlate with a chronic engagement of the pathway. We demonstrate here that half of the STING-expressing cancer cells from the NCI60 panel rapidly increased expression of pro-tumorigenic IL-6 upon genotoxic DNA damage, often independent of type-I IFN responses. While preferentially dependent on canonical STING, we demonstrate that genotoxic DNA damage induced by camptothecin (CPT) also drove IL-6 production through non-canonical STING signaling in selected cancer cells. Consequently, pharmacological inhibition of canonical STING failed to broadly inhibit IL-6 production induced by CPT, although this could be achieved through downstream ERK1/2 inhibition. Finally, prolonged inhibition of canonical STING signaling was associated with increased colony formation of MG-63 cells, highlighting the duality of STING signaling in also restraining the growth of selected cancer cells. Collectively, our findings demonstrate that genotoxic-induced DNA damage frequently leads to the rapid production of pro-tumorigenic IL-6 in cancer cells, independent of an IFN signature, through canonical and non-canonical STING activation; this underlines the complexity of STING engagement in human cancer cells, with frequent acute pro-tumorigenic activities induced by DNA damage. We propose that inhibition of ERK1/2 may help curb such pro-tumorigenic responses to DNA-damage, while preserving the anti-proliferative effects of the STING-interferon axis.

scholarly journals A Novel and Efficient Approach for Screening Cancer Cell Specific Monoclonal Antibodies

2019 ◽  
Author(s):  
Xin-Hui Pei
Keyword(s):  
Monoclonal Antibodies ◽  
Cancer Cells ◽  
Cancer Cell ◽  
Human Liver ◽  
Human Cancer ◽  
Human Cells ◽  
Specific Antibodies ◽  
Human Cancer Cells ◽  
Normal Human ◽  
Normal Human Cells

AbstractCancer cell specific antibodies are pivotal tools in developing new immunotherapies for treating cancers. However, acquirement of cancer cell specific antibodies is time-consuming and often arduous. To circumvent such a barrier, we developed a novel antibody-screening method that can be used to efficiently produce cancer cell specific antibodies by an ‘antibody filter’ mechanism. First, we used normal human cells to perform the immunization in mice and collected the antisera. Second, we used human cancer cells together with the antisera against normal human cells to immunize another batch of mice. Theoretically, the antisera were able to neutralize the antigens from normal human cells, and therefore specific antigens only expressed in cancer cells could take advantage of the immunization. Third, we screened positive clones that are specific for cancer cells but not normal cells. Using this conceptual method, we successfully obtained 11 monoclonal antibodies that are specific for a human liver cancer cells line (HepG2) but not for a normal human liver cell line (HH). In addition, these clones failed to recognize other human cancer cells originated from different tissues, further highlighting the specificity. Collectively, we provide a novel and effective approach for screening cancer cell specific monoclonal antibodies, which may significantly facilitate the development of new anti-cancer therapeutics.

scholarly journals Antiproliferation effect of sulforaphene isolated from radish (Raphanus sativus L.) seeds on A549 cells

2020 ◽  
Vol 63 (1) ◽  
Author(s):  
Sooyeon Lim ◽  
Jin-Chul Ahn ◽  
Eun Jin Lee ◽  
Jongkee Kim
Keyword(s):  
Cancer Cells ◽  
Cell Lines ◽  
Cancer Cell ◽  
Human Cancer ◽  
A549 Cells ◽  
Cancer Cell Lines ◽  
Human Cancer Cells ◽  
Induced Apoptosis ◽  
Ht 29 ◽  
A549 Lung

Abstract Sulforaphene (SFE), a major isothiocyanate in radish seeds, is a close chemical relative of sulforaphane (SFA) isolated from broccoli seeds and florets. The anti-proliferative mechanisms of SFA against cancer cells have been well investigated, but little is known about the potential anti-proliferative effects of SFE. In this study, we showed that SFE purified from radish seeds inhibited the growth of six cancer cell lines (A549, CHO, HeLa, Hepa1c1c7, HT-29, and LnCaP), with relative half maximal inhibitory concentration values ranging from 1.37 to 3.31 μg/mL. Among the six cancer cell lines, SFE showed the greatest growth inhibition against A549 lung cancer cells, where it induced apoptosis by changing the levels of poly(ADP-ribose) polymerase and caspase-3, -8, and -9. Our results indicate that SFE from radish seeds may have significant anti-proliferative potency against a broad range of human cancer cells via induction of apoptosis.

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