Caspase-8 is a cysteine protease that plays an essential role in apoptosis. Consistently with its canonical proapoptotic function, cancer cells may genetically or epigenetically downregulate its expression. Unexpectedly, Caspase-8 is often retained in cancer, suggesting the presence of alternative mechanisms that may be exploited by cancer cells to their own benefit. In this regard, we reported that Src tyrosine kinase, which is aberrantly activated in many tumors, promotes Caspase-8 phosphorylation on Tyrosine 380 (Y380) preventing its full activation. Here, we investigated the significance of Caspase-8 expression and of its phosphorylation on Y380 in glioblastoma, a brain tumor where both Caspase-8 expression and Src activity are often aberrantly upregulated. Transcriptomic analyses identified inflammatory response as a major target of Caspase-8, and in particular, NFκB signaling as one of the most affected pathways. More importantly, we could show that Src-dependent phosphorylation of Caspase-8 on Y380 drives the assembly of a multiprotein complex that triggers NFκB activation, thereby inducing the expression of inflammatory and pro-angiogenic factors. Remarkably, phosphorylation on Y380 sustains neoangiogenesis and resistance to radiotherapy. In summary, our work identifies a novel interplay between Src kinase and Caspase-8 that allows cancer cells to hijack Caspase-8 to sustain tumor growth.
This is a preview of subscription content, access via your institution
Subscribe to Journal
Get full journal access for 1 year
only $9.92 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Tax calculation will be finalised during checkout.
Get time limited or full article access on ReadCube.
All prices are NET prices.
All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. Additional data related to this paper may be requested from the authors.
Network CGAR. Comprehensive genomic characterization defines human glioblastoma genes and core pathways. Nature. 2008;455:1061–8.
Stupp R, Mason WP, van den Bent MJ, Weller M, Fisher B, Taphoorn MJ, et al. Radiotherapy plus concomitant and adjuvant temozolomide for glioblastoma. N Engl J Med. 2005;352:987–96.
Verhaak RG, Hoadley KA, Purdom E, Wang V, Qi Y, Wilkerson MD, et al. Integrated genomic analysis identifies clinically relevant subtypes of glioblastoma characterized by abnormalities in PDGFRA, IDH1, EGFR, and NF1. Cancer Cell. 2010;17:98–110.
Brennan CW, Verhaak RG, McKenna A, Campos B, Noushmehr H, Salama SR, et al. The somatic genomic landscape of glioblastoma. Cell. 2013;155:462–77.
Bjorge JD, Jakymiw A, Fujita DJ. Selected glimpses into the activation and function of Src kinase. Oncogene. 2000;19:5620–35.
Ahluwalia MS, de Groot J, Liu WM, Gladson CL. Targeting SRC in glioblastoma tumors and brain metastases: rationale and preclinical studies. Cancer Lett. 2010;298:139–49.
Du J, Bernasconi P, Clauser KR, Mani DR, Finn SP, Beroukhim R, et al. Bead-based profiling of tyrosine kinase phosphorylation identifies SRC as a potential target for glioblastoma therapy. Nat Biotechnol. 2009;27:77–83.
Cirotti C, Contadini C, Barilà D. SRC kinase in glioblastoma: news from an old acquaintance. Cancers. 2020;12:1558.
Stupack DG. Caspase-8 as a therapeutic target in cancer. Cancer Lett. 2013;332:133–40.
Fianco G, Mongiardi MP, Levi A, De Luca T, Desideri M, Trisciuoglio D, et al. Caspase-8 contributes to angiogenesis and chemotherapy resistance in glioblastoma. Elife. 2017;6:e22593.
Müller I, Strozyk E, Schindler S, Beissert S, Oo HZ, Sauter T, et al. Cancer cells employ nuclear Caspase-8 to overcome the p53-dependent G2/M checkpoint through cleavage of USP28. Mol Cell. 2020;77:970–84. e977.
Fianco G, Contadini C, Ferri A, Cirotti C, Stagni V, Barilà D. Caspase-8: a novel target to overcome resistance to chemotherapy in glioblastoma. Int J Mol Sci. 2018;19:3798.
Fulda S. Cell death-based treatment of glioblastoma. Cell Death Dis. 2018;9:121.
Cursi S, Rufini A, Stagni V, Condo I, Matafora V, Bachi A, et al. Src kinase phosphorylates caspase-8 on Tyr380: a novel mechanism of apoptosis suppression. Embo J. 2006;25:1895–905.
Powley IR, Hughes MA, Cain K, MacFarlane M. Caspase-8 tyrosine-380 phosphorylation inhibits CD95 DISC function by preventing procaspase-8 maturation and cycling within the complex. Oncogene. 2016;35:5629–40.
Torres VA, Mielgo A, Barila D, Anderson DH, Stupack D. Caspase 8 promotes peripheral localization and activation of Rab5. J Biol Chem. 2008;283:36280–9.
Barbero S, Barila D, Mielgo A, Stagni V, Clair K, Stupack D. Identification of a critical tyrosine residue in caspase 8 that promotes cell migration. J Biol Chem. 2008;283:13031–4.
Barbero S, Mielgo A, Torres V, Teitz T, Shields DJ, Mikolon D, et al. Caspase-8 association with the focal adhesion complex promotes tumor cell migration and metastasis. Cancer Res. 2009;69:3755–63.
Keller N, Ozmadenci D, Ichim G, Stupack D. Caspase-8 function, and phosphorylation, in cell migration. Semin Cell Dev Biol. 2018;82:105–17.
Fianco G, Cenci C, Barilà D. Caspase-8 expression and its Src-dependent phosphorylation on Tyr380 promote cancer cell neoplastic transformation and resistance to anoikis. Exp Cell Res. 2016;347:114–22.
Huang DW, Sherman BT, Lempicki RA. Systematic and integrative analysis of large gene lists using DAVID bioinformatics resources. Nat Protoc. 2009;4:44–57.
Wingender E, Dietze P, Karas H, Knüppel R. TRANSFAC: a database on transcription factors and their DNA binding sites. Nucleic Acids Res. 1996;24:238–41.
Minata M, Audia A, Shi J, Lu S, Bernstock J, Pavlyukov MS, et al. Phenotypic plasticity of invasive edge glioma stem-like cells in response to ionizing radiation. Cell Rep. 2019;26:1893–905. e1897.
Mao P, Joshi K, Li J, Kim SH, Li P, Santana-Santos L, et al. Mesenchymal glioma stem cells are maintained by activated glycolytic metabolism involving aldehyde dehydrogenase 1A3. Proc Natl Acad Sci USA. 2013;110:8644–9.
Humphreys L, Espona-Fiedler M, Longley DB. FLIP as a therapeutic target in cancer. FEBS J. 2018;285:4104–23.
Oztürk S, Schleich K, Lavrik IN. Cellular FLICE-like inhibitory proteins (c-FLIPs): fine-tuners of life and death decisions. Exp Cell Res. 2012;318:1324–31.
Henry CM, Martin SJ. Caspase-8 acts in a non-enzymatic role as a scaffold for assembly of a pro-inflammatory “FADDosome” complex upon TRAIL stimulation. Mol Cell. 2017;65:715–29. e715.
Chaudhary PM, Eby MT, Jasmin A, Kumar A, Liu L, Hood L. Activation of the NF-kappaB pathway by caspase 8 and its homologs. Oncogene. 2000;19:4451–60.
Su H, Bidère N, Zheng L, Cubre A, Sakai K, Dale J, et al. Requirement for caspase-8 in NF-kappaB activation by antigen receptor. Science. 2005;307:1465–8.
Bidère N, Snow AL, Sakai K, Zheng L, Lenardo MJ. Caspase-8 regulation by direct interaction with TRAF6 in T cell receptor-induced NF-kappaB activation. Curr Biol. 2006;16:1666–71.
Rébé C, Cathelin S, Launay S, Filomenko R, Prévotat L, L’Ollivier C, et al. Caspase-8 prevents sustained activation of NF-kappaB in monocytes undergoing macrophagic differentiation. Blood. 2007;109:1442–50.
Moen SH, Westhrin M, Zahoor M, Nørgaard NN, Hella H, Størdal B, et al. Caspase-8 regulates the expression of pro- and anti-inflammatory cytokines in human bone marrow-derived mesenchymal stromal cells. Immun Inflamm Dis. 2016;4:327–37.
Keller N, Mares J, Zerbe O, Grütter MG. Structural and biochemical studies on procaspase-8: new insights on initiator caspase activation. Structure. 2009;17:438–48.
Keller N, Grütter MG, Zerbe O. Studies of the molecular mechanism of caspase-8 activation by solution NMR. Cell Death Differ. 2010;17:710–8.
Bhat KPL, Balasubramaniyan V, Vaillant B, Ezhilarasan R, Hummelink K, Hollingsworth F, et al. Mesenchymal differentiation mediated by NF-κB promotes radiation resistance in glioblastoma. Cancer Cell. 2013;24:331–46.
Pordanjani SM, Hosseinimehr SJ. The Role of NF-kB inhibitors in cell response to radiation. Curr Med Chem. 2016;23:3951–63.
Alhalabi OT, Fletcher MNC, Hielscher T, Kessler T, Lokumcu T, Baumgartner U, et al. A novel patient stratification strategy to enhance the therapeutic efficacy of dasatinib in glioblastoma. Neuro Oncol. 2021;24:39–51.
Stagni V, Mingardi M, Santini S, Giaccari D, Barila D. ATM kinase activity modulates cFLIP protein levels: potential interplay between DNA damage signalling and TRAIL-induced apoptosis. Carcinogenesis. 2010;31:1956–63.
D’Antonio M, D’Onorio De Meo P, Pallocca M, Picardi E, D’Erchia AM, Calogero RA, et al. RAP: RNA-Seq Analysis Pipeline, a new cloud-based NGS web application. BMC Genomics. 2015;16:S3.
Trapnell C, Roberts A, Goff L, Pertea G, Kim D, Kelley DR, et al. Differential gene and transcript expression analysis of RNA-seq experiments with TopHat and Cufflinks. Nat Protoc. 2012;7:562–78.
We thank Maria Pia Gentileschi for kindly providing technical support for irradiation experiments and all the members of our lab for critical reading of the manuscript and for helpful discussion.
This work has been supported by research grants from Associazione Italiana per la Ricerca sul Cancro AIRC-IG2016-n.19069, AIRC-IG2021-n.26230, and Italian Ministry of Health, RF-2016-02362022 to DB; CCo work also been supported by AIRC-IG2016-n.19069 and AIRC-IG2021-n.26230, AF PhD fellowship was supported from MUR; MDM was supported by a FIRC-AIRC fellowship for Italy. The research leading to these results has received funding from AIRC under IG 2020 - ID. 24315 project – P.I. DDB; CCi has been supported by a FIRC-AIRC fellowship for Italy “Filomena Todini”. This work was also supported by United States National Institutes of Health (NIH) grants NS080939, NS116802, and CA258248 (FF).
The authors declare no competing interests.
All procedures involving mice handling and care conformed to protocols approved by the Regina Elena National Cancer Institute (Rome, Italy) in compliance with national (D.L. N.116, G.U., suppl. 40, 18-2-1992 and N. 26, G.U. March 4, 2014) and international (EEC Council Directive 2010/63/EU, OJ L 276/33, 22-09-2010; National Institutes of Health Guide for the Care and Use of Laboratory Animals, US National Research Council, 2011) law and policies. The study was approved by the Italian Ministry of Health (approval number:342/2019-PR).
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Edited by M. Piacentini
About this article
Cite this article
Contadini, C., Ferri, A., Di Martile, M. et al. Caspase-8 as a novel mediator linking Src kinase signaling to enhanced glioblastoma malignancy. Cell Death Differ (2022). https://doi.org/10.1038/s41418-022-01093-x