https://doi.org/10.1177/0300891620930803 Tumori Journal 1–10 © Fondazione IRCCS Istituto Nazionale dei Tumori 2020 Article reuse guidelines: sagepub.com/journals-permissions DOI: 10.1177/0300891620930803 journals.sagepub.com/home/tmj TJ Tumori Journal Association of high TUBB3 with resistance to adjuvant docetaxel- based chemotherapy in gastric cancer: translational study of ITACA-S Maria Di Bartolomeo 1 , Alessandra Raimondi 1 , Fabiola Cecchi 2 , Daniel V.T. Catenacci 3 , Sarit Schwartz 2 , Shankar Sellappan 2 , Yuan Tian 2 , Rosalba Miceli 4 , Alessandro Pellegrinelli 5 , Elisa Giommoni 6 , Enrico Aitini 7 , Francesca Spada 8 , Gerardo Rosati 9 , Alberto Marchet 10 , Francesca Pucci 11 , Alberto Zaniboni 12 , Stefano Tamberi 13 , Tiziana Pressiani 14 , Gianni Sanna 15 , Maurizio Cantore 16 , Stefania Mosconi 17 , Paola Bolzoni 18 , Carmine Pinto 19 , Lorenza Landi 20 , Hector Josè Soto Parra 21 , Luigi Cavanna 22 , Salvatore Corallo 1 , Antonia Martinetti 1 , Todd A. Hembrough 2 and Filippo Pietrantonio 1,23 Abstract Background: No predictive markers for chemotherapy activity have been validated in gastric cancer (GC). The potential value of class III β-tubulin (TUBB3) as biomarker for prognosis and resistance to taxane-based therapy was reported. Methods: We analyzed GC samples of patients enrolled in the Intergroup Trial of Adjuvant Chemotherapy in Adenocarcinoma of the Stomach (ITACA-S), a randomized adjuvant study comparing 5-fluorouracil/leucovorin (5-FU/LV) and docetaxel-based sequential chemotherapy. TUBB3 was quantitated by selected reaction monitoring mass spectrometry and patients were stratified using a threshold of 750 attomoles per microgram (amol/μg). Cox proportional 1 Department of Medical Oncology, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy 2 NantOmics, Rockville, MD 3 Department of Medicine, University of Chicago, Chicago, IL 4 Department of Medical Statistics, Biometry, and Bioinformatics, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy 5 Pathology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy 6 Medical Oncology, Azienda Ospedaliera-Università Careggi, Firenze, Italy 7 Medical Oncology, Ospedale di Suzzara, Mantova, Italy 8 Gastrointestinal Oncology and Neuroendocrine Tumors, Istituto Oncologico Europeo, Milan, Italy 9 Medical Oncology, Azienda Ospedaliera “San Carlo,” Potenza, Italy 10 Surgery, Oncology and Gastroenterology Department, Azienda Ospedaliera di Padova, Padova, Italy 11 Medical Oncology, Azienda Ospedaliera di Parma, Parma, Italy 12 Oncology Department, Istituto Ospedaliero Fondazione Poliambulanza, Brescia, Italy 13 Oncology Department, AUSL Romagna, Ravenna, Italy 14 Medical Oncology and Hematology, Istituto Clinico Humanitas, Rozzano, Milan, Italy 15 Medical Oncology, Istituto Ospedaliero dell’Università di Sassari, Sassari, Italy 16 Medical Oncology, Azienda Ospedaliera “Carlo Poma,” Mantova, Italy 17 Medical Oncology, ASST Papa Giovanni XXIII, Bergamo, Italy 18 Medical Oncology, Presidio Ospedaliero “Serbelloni” di Gorgonzola, Melegnano, Italy 19 Medical Oncology, Arcispedale Santa Maria Nuova Azienda Ospedaliera di Reggio Emilia, Reggio Emilia, Italy 20 Medical Oncology, Presidio Ospedaliero di Livorno, Livorno, Italy 21 Medical Oncology, Policlinico Vittorio Emanuele, Presidio Gaspare Rodolico, Catania, Italy 22 Oncology-Hematology Department, Ospedale Civile “Guglielmo da Saliceto,” Piacenza, Italy 23 Department of Oncology and Hemato-oncology, University of Milan, Milan, Italy Corresponding author: Maria Di Bartolomeo, MD, Department of Medical Oncology, Fondazione IRCCS Istituto Nazionale dei Tumori, Via G. Venezian, 1, Milan 20133, Italy. Email: maria.dibartolomeo@istitutotumori.mi.it 930803TMJ 0 0 10.1177/0300891620930803Tumori JournalDi Bartolomeo et al. research-article 2020 Original Research Article