bims-istrec 2022-12-11 papers

bims-istrec

Biomed News

on Integrated stress response in cancer

Issue of 2022–12–11
seven papers selected by
the Vincenzo Ciminale lab, Istituto Oncologico Veneto

Isoquercitrin Induces Endoplasmic Reticulum Stress and Immunogenic Cell Death in Gastric Cancer Cells.
Saikosaponin D Inducing Apoptosis and Autophagy through the Activation of Endoplasmic Reticulum Stress in Glioblastoma.
Small-molecule inhibitors of the PERK-mediated Unfolded Protein Response signaling pathway in targeted therapy for colorectal cancer.
Exploring and validating the metastasis mechanism of pathenolide interfering with cutaneous melanoma through ER stress-dependent apoptosis based on the network pharmacology.
BRCA1 mediates protein homeostasis through the ubiquitination of PERK and IRE1.
Drug resistance mechanisms create targetable proteostatic vulnerabilities in Her2+ breast cancers.
Upregulation of Glutaminyl Cyclase Contributes to ERS-Induced Apoptosis in PC12 Cells.

Biochem Genet. 2022 Dec 08.

Isoquercitrin Induces Endoplasmic Reticulum Stress and Immunogenic Cell Death in Gastric Cancer Cells.

Jiang Liu, LiJun Ren, HaoWen Wang, Zuowei Li.

  Isoquercitrin is a natural flavonoid quercetin with anti-inflammatory, anti-anaphylactic, antiviral, and anticancer activities. Here, we investigated the effect of isoquercitrin on immunogenic cell death (ICD) of gastric cancer (GC). The effect of isoquercitrin on GC cell lines (AGS and HGC-27) was evaluated using cell counting kit-8 assays, colony formation assays, Annexin V/PI apoptosis detection kit, western blot analysis, JC-1 staining, immunofluorescence assays, and enzyme-linked immunosorbent assay. Isoquercitrin at doses greater than 20 μM had significant inhibitory effects on the survival of GC cell lines, including HGC-27, AGS, MKN-45, and SNU-1. Isoquercitrin treatment decreased GC cell colony formation in a dose-dependent manner and induced apoptosis accompanied by downregulation of BCL-2 and upregulation of BAX, cleaved caspase-3, and caspase-12. In addition, isoquercitrin promoted the disruption of mitochondrial membrane potential in GC cells. The GC cell surface levels of calreticulin (CRT) and extracellular levels of CRT, ATP, and HMGB1 were enhanced by treatment with isoquercitrin. The protein levels of HMGB1, HSP70, and HSP90 were upregulated by isoquercitrin in a dose-dependent manner. Moreover, the endoplasmic reticulum (ER) stress inhibitor 4-phenylbutyrate reversed isoquercitrin-induced ICD in GC cells. Overall, our data suggested that isoquercitrin induces ER stress and ICD in GC cells. Isoquercitrin may be a candidate anticancer drug for the treatment of GC.

Keywords:  Endoplasmic reticulum stress; Gastric cancer; Immunogenic cell death; Isoquercitrin; Progression

DOI:  https://doi.org/10.1007/s10528-022-10309-1
Biomed Res Int. 2022 ;2022 5489553

Saikosaponin D Inducing Apoptosis and Autophagy through the Activation of Endoplasmic Reticulum Stress in Glioblastoma.

Guimei Liu, Yuehong Guan, Yongxian Liu, Yaping Wang, Jing Zhang, Yusi Liu, Xiaobin Liu.

Saikosaponin D (SSD), a saponin derivative, is extracted from Bupleurum falcatum. It exhibits an inhibitory effect on a number of tumor cells and is relatively safe when used at therapeutic doses. However, its effects on glioblastoma multiforme (GBM) have not been fully explored. This study is aimed at investigating the cytotoxic effects of SSD in GBM cell lines. SSD induces apoptosis and autophagy by activating endoplasmic reticulum (ER) stress in GBM cells. GBM cell proliferation activity and morphology were observed using the Cell Counting Kit-8 assay and hematoxylin and eosin staining. Hoechst 33258 fluorescence staining and flow cytometry were performed to assess apoptosis. Western blotting and immunocytochemical staining were used to detect protein expression and distribution. SSD significantly inhibited the proliferation of RG-2, U87-MG, and U251 cells in a dose-dependent manner, and the proportion of apoptotic cells increased significantly. Additionally, the expressions of ER-, apoptosis-, and autophagy-related proteins were significantly upregulated and distributed in the cytoplasm and nucleus. Therefore, SSD may be considered a novel treatment option for GBM. This study demonstrated the anti-GBM effect of SSD from the perspectives of cell apoptosis and autophagy.

DOI: https://doi.org/10.1155/2022/5489553
Pol Przegl Chir. 2022 Mar 15. 94(6): 17-25

Small-molecule inhibitors of the PERK-mediated Unfolded Protein Response signaling pathway in targeted therapy for colorectal cancer.

Wioletta Rozpedek-Kaminska, Danuta Piotrzkowska, Grzegorz Galita, Dariusz Pytel, Ewa Kucharska, Łukasz Dziki, Adam Dziki, Ireneusz Majsterek.

 Introduction: The newest data has reported that endoplasmic reticulum (ER) stress and PERK-dependent Unfolded Protein Response (UPR) signaling pathway may constitute a key factor in colorectal cancer (CRC) pathogenesis on the molecular level. Nowadays used anti-cancer treatment strategies are still insufficient, since patients suffer from various side effects that are directly evoked via therapeutic agents characterized by non-specific action in normal and cancer cells. Aim: Thereby, the main aim of the presented research was to analyze the effectiveness of the small-molecule PERK inhibitor NCI 12487 in an in vitro cellular model of CRC. Materials and methods: The study was performed on colorectal cancer HT-29 and normal human colon epithelial CCD 841 CoN cell lines. The cytotoxicity was measured by XTT assay, evaluation of apoptosis was performed by caspase-3 assay, whereas cell cycle analysis via the propidium iodide (PI) staining. Results: Results obtained have demonstrated that the investigated compound is selective only for HT-29 cancer cells, since at 25 μM concentration it significantly decreased HT-29 cells viability in a dose- and time-dependent manner, evoked increased caspase-3 activity and arrest in the G2/M phase of the cell cycle. Moreover, NCI 12487 compound markedly decreased HT-29 cells viability, increased caspase-3 activity and percentage of cells in sub-G0/G1, thus promoted apoptosis of cancer HT-29 cells with induced ER stress conditions. Conclusion: Thus, based on the results obtained in this study it may be concluded that small-molecule modulators of the PERK-dependent UPR signaling pathway may constitute an innovative, targeted treatment strategy against CRC.

Keywords: PERK inhibitors; apoptosis; cancer treatment; colorectal cancer; endoplasmic reticulum stress; unfolded protein response

DOI: https://doi.org/10.5604/01.3001.0015.7948
Phytochem Anal. 2022 Dec 07.

Exploring and validating the metastasis mechanism of pathenolide interfering with cutaneous melanoma through ER stress-dependent apoptosis based on the network pharmacology.

Li-Ping Liu, Ning Liu, Han-Ni Zhang, Ding Li.

   BACKGROUND: This study aimed to explore the mechanism of parthenolide in inhibiting melanoma metastasis through network pharmacology and cell experiment.
MATERIALS AND METHODS: This research obtained the targets of the drug from the HERB database and PubChem database, the differential expression gene of metastatic cutaneous melanoma was obtained by differentially expression gene analysis of four Gene Expression Omnibus (GEO) datasets. The intersection of drug targets and differentially expression genes were considered to be related to drugs that inhibit metastasis of cutaneous melanoma. The STRING database was used to construct the protein-protein interaction (PPI) network, and cytohubba package in Cytoscape software was used to rank the PPI network targets. The enrichment analysis was used to screen out the relevance Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and gene ontology to explain the underlying mechanism of drug inhibiting the cutaneous melanoma metastatic; cell viability, apoptosis, cell migration and protein levels were assessed using cell counting kit-8 (CCK-8) assay, Annexin V-FITC/PI assay, wound healing assay, respectively. Finally, combining pathway maps and literature, we detected ATF4 and proteins upstream and downstream of ATF4 through Western blot.
RESULTS: A total of 87 targets were screened out from the drug databases, and a total of 1635 differentially expression genes was obtained from the differentially expression genes analysis of GEO datasets, a total of nine targets (VEGFA, ANXA5, ICAM1, SELE, NFKBIA, ATF4, CTNNB1, SELP and HPGDS) were considered to be related to drugs that inhibit metastasis of cutaneous melanoma. The result of enrichment analysis showed that the drug inhibits the metastatic of cutaneous melanoma through multiple pathways such as TNF signalling pathway, lipid and atherosclerosis and fluid shear stress and atherosclerosis, relevance multiple biological processes, cellular components and molecular function; cell experiments showed that parthenolide could inhibit tumour cell migration and induce a decrease of cell viability. Flow cytometry results showed that parthenolide induced tumour cell apoptosis. Western blot results suggested that parthenolide exerted therapeutic effects by regulating ATF4 protein and its upstream and downstream proteins, namely endoplasmic reticulum (ER) stress signalling pathway.
CONCLUSION: Parthenolide induces ER stress-dependent apoptosis in melanoma cells.

Keywords:  ER stress; apoptosis; cutaneous melanoma; network pharmacology; parthenolide

DOI:  https://doi.org/10.1002/pca.3193
iScience. 2022 Dec 22. 25(12): 105626

BRCA1 mediates protein homeostasis through the ubiquitination of PERK and IRE1.

Robert Hromas, Gayathri Srinivasan, Ming Yang, Aruna Jaiswal, Taylor A Totterdale, Linda Phillips, Austin Kirby, Nazli Khodayari, Mark Brantley, Elizabeth A Williamson, Kimi Y Kong.

  Tumors with BRCA1 mutations have poor prognoses due to genomic instability. Yet this genomic instability has risks and BRCA1-deficient (def) cancer cells must develop pathways to mitigate these risks. One such risk is the accumulation of unfolded proteins in BRCA1-def cancers from increased mutations due to their loss of genomic integrity. Little is known about how BRCA1-def cancers survive their genomic instability. Here we show that BRCA1 is an E3 ligase in the endoplasmic reticulum (ER) that targets the unfolded protein response (UPR) stress sensors, Eukaryotic Translation Initiation Factor 2-alpha Kinase 3 (PERK) and Serine/Threonine-Protein Kinase/Endoribonuclease Inositol-Requiring Enzyme 1 (IRE1) for ubiquitination and subsequent proteasome-mediated degradation. When BRCA1 is mutated or depleted, both PERK and IRE1 protein levels are increased, resulting in a constitutively activated UPR. Furthermore, the inhibition of protein folding or UPR signaling markedly decreases the overall survival of BRCA1-def cancer cells. Our findings define a mechanism used by the BRCA1-def cancer cells to survive their increased unfolded protein burden which can be used to develop new therapeutic strategies to treat these cancers.

Keywords:  Cancer; Cell biology; Functional aspects of cell biology

DOI:  https://doi.org/10.1016/j.isci.2022.105626
PLoS One. 2022 ;17(12): e0256788

Drug resistance mechanisms create targetable proteostatic vulnerabilities in Her2+ breast cancers.

Navneet Singh, Lindsey Romick-Rosendale, Miki Watanabe-Chailland, Lisa M Privette Vinnedge, Kakajan Komurov.

Oncogenic kinase inhibitors show short-lived responses in the clinic due to high rate of acquired resistance. We previously showed that pharmacologically exploiting oncogene-induced proteotoxic stress can be a viable alternative to oncogene-targeted therapy. Here, we performed extensive analyses of the transcriptomic, metabolomic and proteostatic perturbations during the course of treatment of Her2+ breast cancer cells with a Her2 inhibitor covering the drug response, resistance, relapse and drug withdrawal phases. We found that acute Her2 inhibition, in addition to blocking mitogenic signaling, leads to significant decline in the glucose uptake, and shutdown of glycolysis and of global protein synthesis. During prolonged therapy, compensatory overexpression of Her3 allows for the reactivation of mitogenic signaling pathways, but fails to re-engage the glucose uptake and glycolysis, resulting in proteotoxic ER stress, which maintains the protein synthesis block and growth inhibition. Her3-mediated cell proliferation under ER stress during prolonged Her2 inhibition is enabled due to the overexpression of the eIF2 phosphatase GADD34, which uncouples protein synthesis block from the ER stress response to allow for active cell growth. We show that this imbalance in the mitogenic and proteostatic signaling created during the acquired resistance to anti-Her2 therapy imposes a specific vulnerability to the inhibition of the endoplasmic reticulum quality control machinery. The latter is more pronounced in the drug withdrawal phase, where the de-inhibition of Her2 creates an acute surge in the downstream signaling pathways and exacerbates the proteostatic imbalance. Therefore, the acquired resistance mechanisms to oncogenic kinase inhibitors may create secondary vulnerabilities that could be exploited in the clinic.

DOI: https://doi.org/10.1371/journal.pone.0256788
Biomed Res Int. 2022 ;2022 4154697

Upregulation of Glutaminyl Cyclase Contributes to ERS-Induced Apoptosis in PC12 Cells.

Qi Shang, Xi Yu, Na Ouyang, Pan Xu, Xiaojie Chen, Yinan Wang, Chenyang Li, Xiaojuan Wang, Xifeng Lu, Chenshu Xu, Haiqiang Wu.

Glutaminyl cyclase (QC) is responsible for converting the N-terminal glutaminyl and glutamyl of the proteins into pyroglutamate (pE) through cyclization. It has been confirmed that QC catalyzes the formation of neurotoxic pE-modified Aβ in the brain of AD patients. But the effects of upregulated QC in diverse diseases have not been much clear until recently. Here, RNA sequencing was applied to identify differentially expressed genes (DEGs) in PC12 cells with QC overexpressing or knockdown. A total of 697 DEGs were identified in QC overexpressing cells while only 77 in QC knockdown cells. Multiple bioinformatic approaches revealed that the DEGs in QC overexpressing group were enriched in endoplasmic reticulum stress (ERS) related signaling pathways. The gene expression patterns of 23 DEGs were confirmed by RT-qPCR, in which the genes related to ERS showed the highest consistency. We also revealed the protein levels of GRP78, PERK, CHOP, and PARP-1, and caspase family was significantly upregulated by overexpressing QC. Moreover, overexpressing QC significantly increased apoptosis of PC12 cells in a time dependent manner. However, no significant alteration was observed in QC knockdown cells. Therefore, our study indicated that upregulated QC could induce ERS and apoptosis, which consequently trigger diseases by catalyzing the generation of pE-modified mediators.

DOI: https://doi.org/10.1155/2022/4154697