Abstract
FoxM1 activates genes that regulate S–G2–M cell-cycle progression and, when overexpressed, is associated with poor clinical outcome in multiple cancers. Here we identify FoxM1 as a tumor suppressor in mice that, through its N-terminal domain, binds to and inhibits Ect2 to limit the activity of RhoA GTPase and its effector mDia1, a catalyst of cortical actin nucleation. FoxM1 insufficiency impedes centrosome movement through excessive cortical actin polymerization, thereby causing the formation of nonperpendicular mitotic spindles that missegregate chromosomes and drive tumorigenesis in mice. Importantly, low FOXM1 expression correlates with RhoA GTPase hyperactivity in multiple human cancer types, indicating that suppression of the newly discovered Ect2–RhoA–mDia1 oncogenic axis by FoxM1 is clinically relevant. Furthermore, by dissecting the domain requirements through which FoxM1 inhibits Ect2 guanine nucleotide-exchange factor activity, we provide mechanistic insight for the development of pharmacological approaches that target protumorigenic RhoA activity.
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Data availability
RNA-sequencing data have been deposited in the Gene Expression Omnibus under the accession number GSE130410. Source data are provided with this paper. All other data supporting the findings of this study are available from the corresponding author on reasonable request.
References
Jaffe, A. B. & Hall, A. Rho GTPases: biochemistry and biology. Annu. Rev. Cell Dev. Biol. 21, 247–269 (2005).
Olson, M. F., Ashworth, A. & Hall, A. An essential role for Rho, Rac, and Cdc42 GTPases in cell cycle progression through G1. Science 269, 1270–1272 (1995).
Gerhard, R. et al. Glucosylation of Rho GTPases by Clostridium difficile toxin A triggers apoptosis in intestinal epithelial cells. J. Med. Microbiol. 57, 765–770 (2008).
Provenzano, P. P. & Keely, P. J. Mechanical signaling through the cytoskeleton regulates cell proliferation by coordinated focal adhesion and Rho GTPase signaling. J. Cell Sci. 124, 1195–1205 (2011).
Haga, R. B. & Ridley, A. J. Rho GTPases: regulation and roles in cancer cell biology. Small GTPases 7, 207–221 (2016).
Gomez del Pulgar, T., Benitah, S. A., Valeron, P. F., Espina, C. & Lacal, J. C. Rho GTPase expression in tumourigenesis: evidence for a significant link. Bioessays 27, 602–613 (2005).
Horiuchi, A. et al. Up-regulation of small GTPases, RhoA and RhoC, is associated with tumor progression in ovarian carcinoma. Lab. Invest. 83, 861–870 (2003).
Li, X. R. et al. Overexpression of RhoA is associated with poor prognosis in hepatocellular carcinoma. Eur. J. Surg. Oncol. 32, 1130–1134 (2006).
Kamai, T. et al. Overexpression of RhoA, Rac1, and Cdc42 GTPases is associated with progression in testicular cancer. Clin. Cancer Res. 10, 4799–4805 (2004).
Engers, R. et al. Prognostic relevance of increased Rac GTPase expression in prostate carcinomas. Endocr. Relat. Cancer 14, 245–256 (2007).
Orgaz, J. L., Herraiz, C. & Sanz-Moreno, V. Rho GTPases modulate malignant transformation of tumor cells. Small GTPases 5, e29019 (2014).
Porter, A. P., Papaioannou, A. & Malliri, A. Deregulation of Rho GTPases in cancer. Small GTPases 7, 123–138 (2016).
Fields, A. P. & Justilien, V. The guanine nucleotide exchange factor (GEF) Ect2 is an oncogene in human cancer. Adv. Enzyme Regul. 50, 190–200 (2010).
Tatsumoto, T., Xie, X., Blumenthal, R., Okamoto, I. & Miki, T. Human ECT2 is an exchange factor for Rho GTPases, phosphorylated in G2/M phases, and involved in cytokinesis. J. Cell Biol. 147, 921–928 (1999).
Bandla, S. et al. Comparative genomics of esophageal adenocarcinoma and squamous cell carcinoma. Ann. Thorac. Surg. 93, 1101–1106 (2012).
Sonoda, G. et al. Comparative genomic hybridization detects frequent overrepresentation of chromosomal material from 3q26, 8q24, and 20q13 in human ovarian carcinomas. Genes Chromosomes Cancer 20, 320–328 (1997).
Kim, J. E., Billadeau, D. D. & Chen, J. The tandem BRCT domains of Ect2 are required for both negative and positive regulation of Ect2 in cytokinesis. J. Biol. Chem. 280, 5733–5739 (2005).
Justilien, V., Jameison, L., Der, C. J., Rossman, K. L. & Fields, A. P. Oncogenic activity of Ect2 is regulated through protein kinase C iota-mediated phosphorylation. J. Biol. Chem. 286, 8149–8157 (2011).
Saito, S. et al. Deregulation and mislocalization of the cytokinesis regulator ECT2 activate the Rho signaling pathways leading to malignant transformation. J. Biol. Chem. 279, 7169–7179 (2004).
Justilien, V. et al. Ect2-dependent rRNA synthesis is required for KRAS-TRP53-driven lung adenocarcinoma. Cancer Cell 31, 256–269 (2017).
Laoukili, J. et al. FoxM1 is required for execution of the mitotic programme and chromosome stability. Nat. Cell Biol. 7, 126–136 (2005).
Pilarsky, C., Wenzig, M., Specht, T., Saeger, H. D. & Grutzmann, R. Identification and validation of commonly overexpressed genes in solid tumors by comparison of microarray data. Neoplasia 6, 744–750 (2004).
Halasi, M. & Gartel, A. L. Targeting FOXM1 in cancer. Biochem. Pharmacol. 85, 644–652 (2013).
Barger, C. J., Branick, C., Chee, L. & Karpf, A. R. Pan-cancer analyses reveal genomic features of FOXM1 overexpression in cancer. Cancers (Basel) 11, 251 (2019).
Krupczak-Hollis, K. et al. The mouse Forkhead Box m1 transcription factor is essential for hepatoblast mitosis and development of intrahepatic bile ducts and vessels during liver morphogenesis. Dev. Biol. 276, 74–88 (2004).
Thompson, S. L., Bakhoum, S. F. & Compton, D. A. Mechanisms of chromosomal instability. Curr. Biol. 20, R285–R295 (2010).
Nam, H. J., Naylor, R. M. & van Deursen, J. M. Centrosome dynamics as a source of chromosomal instability. Trends Cell Biol. 25, 65–73 (2015).
Kanakkanthara, A. et al. Cyclin A2 is an RNA binding protein that controls Mre11 mRNA translation. Science 353, 1549–1552 (2016).
van Ree, J. H., Nam, H. J., Jeganathan, K. B., Kanakkanthara, A. & van Deursen, J. M. Pten regulates spindle pole movement through Dlg1-mediated recruitment of Eg5 to centrosomes. Nat. Cell Biol. 18, 814–821 (2016).
Park, H. J. et al. An N-terminal inhibitory domain modulates activity of FoxM1 during cell cycle. Oncogene 27, 1696–1704 (2008).
Laoukili, J. et al. Activation of FoxM1 during G2 requires cyclin A/Cdk-dependent relief of autorepression by the FoxM1 N-terminal domain. Mol. Cell. Biol. 28, 3076–3087 (2008).
Chugh, P. & Paluch, E. K. The actin cortex at a glance. J. Cell Sci. 131, https://doi.org/10.1242/jcs.186254 (2018).
Rosenblatt, J., Cramer, L. P., Baum, B. & McGee, K. M. Myosin II-dependent cortical movement is required for centrosome separation and positioning during mitotic spindle assembly. Cell 117, 361–372 (2004).
Bovellan, M. et al. Cellular control of cortical actin nucleation. Curr. Biol. 24, 1628–1635 (2014).
Matthews, H. K. et al. Changes in Ect2 localization couple actomyosin-dependent cell shape changes to mitotic progression. Dev. Cell 23, 371–383 (2012).
Basant, A. & Glotzer, M. Spatiotemporal regulation of Rhoa during cytokinesis. Curr. Biol. 28, R570–R580 (2018).
Piekny, A. J. & Glotzer, M. Anillin is a scaffold protein that links RhoA, actin, and myosin during cytokinesis. Curr. Biol. 18, 30–36 (2008).
Chugh, P. et al. Actin cortex architecture regulates cell surface tension. Nat. Cell Biol. 19, 689–697 (2017).
Foster, C. T., Gualdrini, F. & Treisman, R. Mutual dependence of the MRTF-SRF and YAP-TEAD pathways in cancer-associated fibroblasts is indirect and mediated by cytoskeletal dynamics. Genes Dev. 31, 2361–2375 (2017).
Yu, O. M. et al. YAP and MRTF-A, transcriptional co-activators of RhoA-mediated gene expression, are critical for glioblastoma tumorigenicity. Oncogene 37, 5492–5507 (2018).
Wang, Y. et al. Comprehensive molecular characterization of the hippo signaling pathway in cancer. Cell Rep. 25, e1305 (2018).
Oka, T., Mazack, V. & Sudol, M. Mst2 and Lats kinases regulate apoptotic function of Yes kinase-associated protein (YAP). J. Biol. Chem. 283, 27534–27546 (2008).
Dupont, S. et al. Role of YAP/TAZ in mechanotransduction. Nature 474, 179–183 (2011).
Feng, X. et al. Hippo-independent activation of YAP by the GNAQ uveal melanoma oncogene through a trio-regulated rho GTPase signaling circuitry. Cancer Cell 25, 831–845 (2014).
Guy, C. T., Cardiff, R. D. & Muller, W. J. Induction of mammary tumors by expression of polyomavirus middle T oncogene: a transgenic mouse model for metastatic disease. Mol. Cell. Biol. 12, 954–961 (1992).
Nobis, M. et al. A RhoA-FRET biosensor mouse for intravital imaging in normal tissue homeostasis and disease contexts. Cell Rep. 21, 274–288 (2017).
Glotzer, M. The molecular requirements for cytokinesis. Science 307, 1735–1739 (2005).
Fields, A. P., Ali, S. A., Justilien, V. & Murray, N. R. Protein kinase Ciota: a versatile oncogene in the lung. Mol. Cell. Oncol. 5, e1190886 (2018).
Thompson, L. L., Jeusset, L. M., Lepage, C. C. & McManus, K. J. Evolving therapeutic strategies to exploit chromosome instability in cancer. Cancers (Basel) 9, 151 (2017).
Chan, K. S., Koh, C. G. & Li, H. Y. Mitosis-targeted anti-cancer therapies: where they stand. Cell Death Dis. 3, e411 (2012).
Bakhoum, S. F. et al. Chromosomal instability drives metastasis through a cytosolic DNA response. Nature 553, 467–472 (2018).
Bolhaqueiro, A. C. F. et al. Ongoing chromosomal instability and karyotype evolution in human colorectal cancer organoids. Nat. Genet. 51, 824–834 (2019).
Burrell, R. A. & Swanton, C. Tumour heterogeneity and the evolution of polyclonal drug resistance. Mol. Oncol. 8, 1095–1111 (2014).
Jamal-Hanjani, M. et al. Tracking the evolution of non-small-cell lung cancer. N. Engl. J. Med. 376, 2109–2121 (2017).
McGranahan, N. & Swanton, C. Biological and therapeutic impact of intratumor heterogeneity in cancer evolution. Cancer Cell 27, 15–26 (2015).
Turajlic, S. & Swanton, C. Metastasis as an evolutionary process. Science 352, 169–175 (2016).
Babu, J. R. et al. Rae1 is an essential mitotic checkpoint regulator that cooperates with Bub3 to prevent chromosome missegregation. J. Cell Biol. 160, 341–353 (2003).
Moffat, J. et al. A lentiviral RNAi library for human and mouse genes applied to an arrayed viral high-content screen. Cell 124, 1283–1298 (2006).
Mitchell, C. & Willenbring, H. A reproducible and well-tolerated method for 2/3 partial hepatectomy in mice. Nat. Protoc. 3, 1167–1170 (2008).
Aziz, K. et al. Ccne1 overexpression causes chromosome instability in liver cells and liver tumor development in mice. Gastroenterology 157, 210–226.e12 (2019).
Jeganathan, K. B., Malureanu, L. & van Deursen, J. M. The Rae1–Nup98 complex prevents aneuploidy by inhibiting securin degradation. Nature 438, 1036–1039 (2005).
Nam, H. J. & van Deursen, J. M. Cyclin B2 and p53 control proper timing of centrosome separation. Nat. Cell Biol. 16, 538–549 (2014).
Macedo, J. C. et al. FoxM1 repression during human aging leads to mitotic decline and aneuploidy-driven full senescence. Nat. Commun. 9, 2834 (2018).
Goldman, M. J. et al. Visualizing and interpreting cancer genomics data via the Xena platform. Nat. Biotechnol. 38, 675–678 (2020).
Ritchie, M. E. et al. limma powers differential expression analyses for RNA-sequencing and microarray studies. Nucleic Acids Res. 43, e47 (2015).
Acknowledgements
We thank B. Childs, R. Naylor and C. Sieben for helpful discussions, and G. Nelson for managing the mouse colony. We thank the transgenic and gene knockout core at Mayo Clinic for generation of all mutant mouse strains, D. Billadeau (Mayo Clinic, Rochester) for the Cofilin 1 antibody, G. Razidlo (Mayo Clinic, Rochester) for Cytochalasin D and GST-PBD construct, S. Kaufmann (Mayo Clinic, Rochester) for H1299 and A549 cell lines and R. Thaler for assistance with the in vitro GEF activity assay. The human tumor results shown here are in whole or part based upon data generated by TCGA Research Network: https://www.cancer.gov/tcga. This work was supported by NIH grant nos. R01 CA096985, CA126828 and CA168709 to J.M.v.D. J.F.L is supported by Mayo Clinic Graduate School of Biomedical Sciences and J.A.K. by NIH grant no. T32 GM65841.
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J.F.L. and J.M.v.D. designed experiments, interpreted data and wrote the manuscript with input from all authors. I.S., C.Z. and H.L. performed RNA sequencing and systems biology analyses. J.A.K. performed experiments pertaining to ROCK-myosin signaling with J.F.L. J.Z. generated the Foxm1 mutant mouse model. B.A.D. and D.J.K. assisted with recombinant protein production and conducted in vitro binding experiments in collaboration with J.F.L. K.B.J. and J.F.L. performed biochemical experiments, and R.F.V. immunofluorescence and histological assessments on mouse tissues with J.F.L. A.P.F., Y.Y. and D.Z. collaborated with J.F.L. on FoxM1-Ect2 binding studies. D.J.B. assisted with data interpretation and statistical analyses. J.M.v.D. supervised and directed all aspects of the study.
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Extended data
Extended Data Fig. 1 Generation of Foxm1 knockout and hypomorphic alleles.
a, Copy number variability (CNV) of the FOXM1 gene in the indicated TCGA cohort. b, Schematic representation of the gene targeting strategy used to generate Foxm1 hypomorph (H) and knockout (–) alleles. c, Quantification of FoxM1 protein levels in MEFs and lung tissue. PonS staining of blotted proteins was used as loading control. d, Western blot analysis of FoxM1 in lysates of the indicated tissues. Western blots are representative of at least 3 independent MEF lines or mice per genotype. e, Overall survival analysis of human colorectal cancer patients from the TCGA COADREAD cohort with indicated FOXM1 gene expression (n = 214 > 10.51, n = 216 < 10.51). Significance determined by Log Rank Test. See source file for uncropped immunoblots.
Extended Data Fig. 2 FoxM1 insufficiency does not perturb common CIN causing mechanisms.
a, MEFs in metaphase with misaligned chromosomes after monastrol washout assay. (See methods). b, Time taken from nuclear envelope breakdown (NEBD) to anaphase onset in MEFs expressing H2B-mRFP. c, Quantification of MEFs with indicated spindle defect. d, Quantification of G2-phase cells with premature centrosome disjunction. (n = 3 independent MEF lines in (a-d). e, Time taken for centrosomes to separate after disjunction to NEBD in MEFs expressing H2B-YFP and γTubulin-tdTomato. (n = 3 + /+ and 4 –/H independent MEF lines). Data represent mean ± s.e.m. None of the analyses were statistically significant after performing one-way ANOVA with Tukey’s correction (a–d) or two-tailed unpaired t-test (e). Scale bar, 10 μm. See source file for original data.
Extended Data Fig. 3 FoxM1 non-transcriptionally regulates centrosome movement independent of Eg5.
a, Left: Images of MEFs in prophase immunostained for Eg5 and γtubulin. Right: Quantification of Eg5 signal at centrosomes. b, Schematic representation and western blot analysis of tdTomato(tdT)-tagged FoxM1 cDNA constructs. N-terminal domain (NTD), Forkhead domain (FHD), Transactivation domain (TAD). Western blots are representative of 3 independent MEF lines per group. c, Quantification of prophases with slow centrosome movement and d, metaphases with non-perpendicular spindles in Foxm1–/H MEFs expressing indicated cDNA constructs. e, Chromosome segregation analysis of MEFs expressing H2B-mRFP as in c. f, Chromosome segregation analysis of Foxm1+/+ MEFs stably expressing FoxM11–232. (n = 3 independent MEF lines per genotype in (a, c–f). g, Representative cell cycle profiles of the indicated propidium iodide-stained MEFs. h, Quantification of cells in the indicated stage of the cell cycle as in g. (n = 6 independent MEF lines per genotype in (g, h). Data represent mean ± s.e.m. Differences are not statistically significant in a, f. Statistics: a, c–e, h one-way ANOVA with Tukey’s correction; f, two-tailed paired t-test. Scale bar, 5 μm. See source file for original data and uncropped immunoblots.
Extended Data Fig. 4 FoxM1 insufficiency does not hyperactivate ROCK-Myosin-II signaling.
a, Left: Images of the indicated MEFs stained for TRITC-Phalloidin and phospho-histoneH3Ser10. Right: Quantification of cortical actin intensity (n = 3 independent MEF lines). b, Left: Images of the indicated MEFs stained with TRITC-Phalloidin. Right: Quantification of cortical actin intensity in telophase (n = 3 independent MEF lines) c, Left: Images of MEFs stained for myosin light chain (MLC2). Right: Quantification of cortical MLC2 intensity (n = 5 independent MEF lines). d, Quantification of cortical actin intensity and e, non-perpendicular spindles in mitotic Foxm1–/– MEFs treated with the indicated drugs for 4 h (n = 3 independent MEF lines). f, Chromosome segregation analysis of MEFs as in d. g, Western blot analysis of MEFs of the indicated genotypes. Western blots are representative of 3 independent experiments. h, Densitometric quantification of band intensity of indicated proteins (n = 9 MEF lines analyzed across 3 independent experiments). i, Left: Images of MEFs stained with phospho-myosin light chain (pMLC2Ser19). Right: Quantification of cortical pMLC2 intensity (n = 7 independent MEF lines). Data represent mean ± s.e.m. Statistics: a–e, h, i one-way ANOVA with Tukey’s correction; f, two-tailed paired t-test. Scale bars, 10 μm. See source file for original data and uncropped immunoblots.
Extended Data Fig. 5 FoxM1 insufficiency does not alter Rac1 and Cdc42 Rho GTPases.
a, Western blot analysis of Foxm1–/– MEFs lentivirally transduced with the indicated shRNAs. PonS staining was used as loading control. b–d, Foxm1–/– MEFs stably expressing indicated shRNAs analyzed for cortical actin intensity (b), incidence of slow centrosome movement in prophase (c), and non-perpendicular spindles in metaphase (d) (n = 5 independent MEF lines in (b–d). e, Left: Western blot analysis of the indicated MEF lysates. β-actin served as a loading control. Right: Densitometric quantification of signals from indicated proteins in the indicated MEFs (n = 9 MEF lines analyzed across 3 independent experiments). f, Left: Western blot analysis of the indicated MEFs. PonS staining was used as loading control. Right: Densitometric quantification of signals from the indicated proteins (n = 9 MEF lines analyzed across 3 independent experiments). All western blots are representative of at least 3 independent experiments. Data represent mean ± s.e.m. Statistics: b–d, one-way ANOVA with Sidak’s correction; e, f, two-tailed unpaired t-test. See source file for original data and uncropped immunoblots.
Extended Data Fig. 6 Ect2 overexpression phenocopies FoxM1 insufficiency.
a, FoxM1 immunoprecipitation from A549 cells, H1299 cells and primary HSFs. b, HA immunoprecipitation from whole-cell mitotic MEF extracts stably expressing indicated FoxM1 cDNA constructs. c, HA immunoprecipitation from extracts of wildtype-MEFs stably expressing HA-FoxM11–232 subject to sub-cellular fractionation: C, cytoplasmic fraction; and N, nuclear fraction. d, Quantification of cortical actin intensity in indicated MEFs stably expressing HA-FoxM11–1232 or empty vector (EV) (n = 3 independent MEF lines). e, Western blot analysis of wildtype (WT) MEFs stably expressing empty-vector (EV) or HA-Ect2. PonS served as loading control. f, Left: Images of MEFs stained with TRITC-Phalloidin Right: Quantification of cortical actin intensity of MEFs as in e (n = 3 independent MEF lines). g, Quantification of prophases with slow centrosome movement and h) metaphases with non-perpendicular spindles as in e. (n = 3 independent MEF lines). i, Chromosome counts and j, chromosome segregation analysis of P5 MEFs as in e. (n = 3 independent MEF lines). All western blots are representative of at least 3 independent experiments or MEF lines. Data represent mean ± s.e.m. Statistics: d, one-way ANOVA with Tukey’s correction; f–j, two-tailed paired t-test. Scale bar, 5 μm. See source file for original data and uncropped immunoblots.
Extended Data Fig. 7 FoxM1-independent cortical actin hypernucleation slows centrosome movement and yields non-perpendicular spindles.
a, Western blot analysis of primary HSFs lentivirally transduced with scramble (shScr) or two independent FOXM1 shRNAs (shFOXM1). PonS staining of blotted proteins served as loading control. b, Left: Images of the indicated metaphases stained with TRITC-Phalloidin as in a. Right: Quantification of cortical actin intensity (n = 3 independent fibroblast lines for shFOXM1 groups and 6 independent lines for shScr group). c, Left: Images of prophases immunostained with γtubulin as in a. Right: Quantification of prophases with slow centrosome movement. (n = 3 independent fibroblast lines for shFOXM1 groups and 6 independent lines for shScr group). d, Quantification of metaphases with non-perpendicular spindles as in a. (n = 3 independent fibroblast lines for shFOXM1 groups and 6 independent lines for shScr group). e, Chromosome segregation analysis of HSFs expressing H2B-mRFP as in a. (n = 3 independent fibroblast lines for shScr and shFOXM1 #2 groups and 4 independent lines for shFOXM1 #1 group). f, Western blot analysis of wildtype MEFs stably expressing the indicated shRNAs. g, Left: Images of wildtype MEFs stably expressing the indicated shRNAs stained with TRITC-Phalloidin. Right: Quantification of cortical actin intensity in wildtype MEFs stably expressing the indicated shRNAs (n = 3 independent MEF lines). h–k, Wildtype MEFs stably expressing the indicated shRNAs analyzed for slow centrosome movement in prophase (h), non-perpendicular spindles in metaphase (i), aneuploidy rates (chromosome counts on metaphase spreads) (j), and chromosome segregation defects (k). (n = 3 independent MEF lines). l, Western blot analysis of the indicated MEFs. m–p, Quantification of cortical actin intensity (m), quantification of prophases with slow centrosome movement (n), metaphases with non-perpendicular spindles (o), aneuploidy rates (chromosome counts on metaphase spreads) on the indicated P5 MEFs (p) (n = 5 independent MEF lines per genotype). q, Quantification of cortical actin and cortical phospho-MLC2Ser19 intensity in Foxm1–/– MEFs after the indicated treatments for 4 h. (n = 3 independent MEF lines). r, Quantification of prophases with slow centrosome movement of wildtype MEFs stably transduced with scr or Capzb shRNA, after treatment with 10 μM ROCK inhibitor Y-27632 for 4 h (n = 5 independent MEF lines). All western blots are representative of at least 3 HSF or MEF lines. Data represent mean ± s.e.m. Statistics: b–k, q, r, one-way ANOVA with Sidak’s correction, m–p, two-tailed unpaired t-test. Scale bar, 5 μm. See source file for original data and uncropped immunoblots.
Extended Data Fig. 8 NTDT corrects mitotic defects caused by Foxm1 insufficiency by inhibiting Ect2-RhoA signaling.
a, Schematic for the generation of NTDT mice. b, Chromosome counts performed on MEFs of indicated genotypes (n = 3 independent MEF lines). c-f, MEFs of indicated genotypes analyzed for cortical actin intensity in metaphase (c), slow centrosome movement in prophase (d), non-perpendicular spindles in metaphase (e), and chromosome segregation errors (f). (n = 3 independent MEF lines). g, Top: Western blot analysis of GTP-bound (active) and total RhoA in indicated mammary tumor extracts. Bottom: Densitometric quantification of RhoA signals. (n = 16 PyVT and 15 PyVT; NTDT tumors analyzed across 3 independent experiments). h–j, Epithelial cells derived from MMTV-PyVT primary tumors, treated with vehicle (Veh) or 3 μg/ml RhoA inhibitor (C3) for 4 h and quantified for non-perpendicular spindles (h), lagging chromosome incidence (i), and cortical actin intensity (j), (n = 3 independent tumor derived lines). k, Western blot analysis of mammary epithelial tumor cells derived from MMTV-PyVT primary tumors lentivirally transduced with the indicated shRNAs. l–n, MMTV-PyVT epithelial tumor cells quantified for non-perpendicular spindles (l), lagging chromosome incidence (m), and cortical actin intensity (n). (n = 7 independent tumor derived lines). All western blots are representative of at least 3 independent experiments or tumor lines. Data represent mean ± s.e.m. Statistics: b–f, one-way ANOVA with Tukey’s correction; g, two-tailed unpaired t-test h–n, two-tailed paired t-test. See source file for original data and uncropped immunoblots.
Extended Data Fig. 9 Hypothetical model for how FoxM1 controls cortical actin nucleation.
Ect2 hyperactivity has been linked to overactive Rho GTPases in human cancers. How Ect2 can become hyperactive remains incompletely understood. Here we identify FoxM1 as a key inhibitor of Ect2 activity and that its complete or partial loss results in increased signaling through the Ect2-RhoA-mDia- signaling axis. We find that FoxM1 binds to Ect2 via its NTD, thereby inhibiting Ect2-mediated activation of RhoA without impacting the activities of two other Rho GTPases, Rac1 and Cdc42 activity. RhoA regulates the actomyosin network through two effectors mDia1, which stimulates actin polymerization, and ROCK which stimulates contractility through MLC activation and F-actin stabilization through LIMK (not shown). We find that FoxM1 selectively inhibits Ect2-mediated activation of mDia1, implying that RhoA activity toward ROCK is independently controlled. Cortical actin hypernucleation resulting from FoxM1 insufficiency slows movement of centrosomes along the cortex, yielding non-perpendicular spindles enriched for merotelic MT-kinetochore attachments that promote aneuploidization and providing a rate of genetic heterogeneity that stimulates tumor formation. FoxM1 independent mechanisms of cortical actin hypernucleation produce the same phenotype, which can be ameliorated by inhibiting myosin activity, indicating that rigidity of the actomyosin cortex is a key determinant of centrosome movement and spindle symmetry.
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Limzerwala, J.F., Jeganathan, K.B., Kloeber, J.A. et al. FoxM1 insufficiency hyperactivates Ect2–RhoA–mDia1 signaling to drive cancer. Nat Cancer 1, 1010–1024 (2020). https://doi.org/10.1038/s43018-020-00116-1
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DOI: https://doi.org/10.1038/s43018-020-00116-1
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