cells Article Glioblastoma Multiforme Stem Cell Cycle Arrest by Alkylaminophenol through the Modulation of EGFR and CSC Signaling Pathways Phuong Doan 1,2,3 , Aliyu Musa 1,4 , Akshaya Murugesan 1,2,5 , Vili Sipilä 1,2 , Nuno R. Candeias 6 , Frank Emmert-Streib 4,7 , Pekka Ruusuvuori 2 , Kirsi Granberg 2,3 , Olli Yli-Harja 2,3,8,9 and Meenakshisundaram Kandhavelu 1,2,3, * 1 Molecular Signaling Lab, Faculty of Medicine and Health Technology, Tampere University, P.O. Box 553, 33101 Tampere, Finland; phuong.doan@tuni.fi (P.D.); aliyu.musa@tuni.fi (A.M.); akshaya.murugesan@tuni.fi (A.M.); vili.sipila@tuni.fi (V.S.) 2 BioMediTech Institute and Faculty of Medicine and Health Technology, Tampere University, Arvo Ylpön katu 34, 33520 Tampere, Finland; pekka.ruusuvuori@tuni.fi (P.R.); kirsi.granberg@tuni.fi (K.G.); olli.yli-harja@tuni.fi (O.Y.-H.) 3 Science Center, Tampere University Hospital, Arvo Ylpön katu 34, 33520 Tampere, Finland 4 Predictive Society and Data Analytics Lab, Faculty of Information Technology and Communication Sciences, Tampere University, 33101 Tampere, Finland; frank.emmert-streib@tuni.fi 5 Department of Biotechnology, Lady Doak College, Thallakulam, Madurai 625002, India 6 LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal; ncandeias@ua.pt 7 Institute of Biosciences and Medical Technology, 33101 Tampere, Finland 8 Computational Systems Biology Group, Faculty of Medicine and Health Technology, Tampere University, P.O. Box 553, 33101 Tampere, Finland 9 Institute for Systems Biology, 1441N 34th Street, Seattle, WA 98103-8904, USA * Correspondence: meenakshisundaram.kandhavelu@tuni.fi; Tel.: +35-8417-4887-72 Received: 19 February 2020; Accepted: 9 March 2020; Published: 10 March 2020   Abstract: Cancer stem cells (CSCs), a small subpopulation of cells existing in the tumor microenvironment promoting cell proliferation and growth. Targeting the stemness of the CSC population would offer a vital therapeutic opportunity. 3,4-Dihydroquinolin-1(2H)-yl)(p-tolyl)methyl)phenol (THTMP), a small synthetic phenol compound, is proposed to play a significant role in controlling the CSC proliferation and survival. We assessed the potential therapeutic effects of THTMP on glioblastoma multiforme (GBM) and its underlying mechanism in various signaling pathways. To fully comprehend the effect of THTMP on the CSCs, CD133 + GBM stem cell (GSC) and CD133 - GBM Non-stem cancer cells (NSCC) population from LN229 and SNB19 cell lines was used. Cell cycle arrest, apoptosis assay and transcriptome analysis were performed for individual cell population. THTMP strongly inhibited NSCC and in a subtle way for GSC in a time-dependent manner and inhibit the resistance variants better than that of temozolomide (TMZ). THTMP arrest the CSC cell population at both G1/S and G2/M phase and induce ROS-mediated apoptosis. Gene expression profiling characterize THTMP as an inhibitor of the p53 signaling pathway causing DNA damage and cell cycle arrest in CSC population. We show that the THTMP majorly affects the EGFR and CSC signaling pathways. Specifically, modulation of key genes involved in Wnt, Notch and Hedgehog, revealed the significant role of THTMP in disrupting the CSCs’ stemness and functions. Moreover, THTMP inhibited cell growth, proliferation and metastasis of multiple mesenchymal patient-tissue derived GBM-cell lines. THTMP arrests GBM stem cell cycle through the modulation of EGFR and CSC signaling pathways. Keywords: GBM stem cells; non-stem cancer cells; resistance population; cell cycle arrest; alkylaminophenol and cell death Cells 2020, 9, 681; doi:10.3390/cells9030681 www.mdpi.com/journal/cells