International Journal of Molecular Sciences Article TRAP1 Regulates Wnt/β-Catenin Pathway through LRP5/6 Receptors Expression Modulation 1, 1, 1 1 Giacomo Lettini y, Valentina Condelli y, Michele Pietrafesa , Fabiana Crispo , Pietro Zoppoli 1 , Francesca Maddalena 1, Ilaria Laurenzana 1 , Alessandro Sgambato 1, Franca Esposito 2,* and Matteo Landriscina 1,3,* 1 Laboratory of Pre-Clinical and Translational Research, IRCCS, Referral Cancer Center of Basilicata, 85028 Rionero in Vulture, PZ, Italy;
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[email protected] (A.S.) 2 Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, 80131 Naples, Italy 3 Medical Oncology Unit, Department of Medical and Surgical Sciences, University of Foggia, 71100 Foggia, Italy * Correspondence:
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[email protected] (M.L.); Tel.: +39-081-7463-145 (F.E.); +39-0881-736-426 (M.L.) These authors have contributed equally to this work. y Received: 4 September 2020; Accepted: 10 October 2020; Published: 13 October 2020 Abstract: Wnt/β-Catenin signaling is involved in embryonic development, regeneration, and cellular differentiation and is responsible for cancer stemness maintenance. The HSP90 molecular chaperone TRAP1 is upregulated in 60–70% of human colorectal carcinomas (CRCs) and favors stem cells maintenance, modulating the Wnt/β-Catenin pathway and preventing β-Catenin phosphorylation/degradation. The role of TRAP1 in the regulation of Wnt/β-Catenin signaling was further investigated in human CRC cell lines, patient-derived spheroids, and CRC specimens.