PLK1 inhibition exhibits strong anti-tumoral activity in CCND1-driven breast cancer metastases with acquired palbociclib resistance

Nom de la revue
Nature Communications
Elodie Montaudon, Joanna Nikitorowicz-Buniak, Laura Sourd, Ludivine Morisset, Rania El Botty, Léa Huguet, Ahmed Dahmani, Pierre Painsec, Fariba Nemati, Sophie Vacher, Walid Chemlali, Julien Masliah-Planchon, Sophie Château-Joubert, Camilla Rega, Mariana Ferreira Leal, Nikiana Simigdala, Sunil Pancholi, Ricardo Ribas, André Nicolas, Didier Meseure, Anne Vincent-Salomon, Cécile Reyes, Audrey Rapinat, David Gentien, Thibaut Larcher, Mylène Bohec, Sylvain Baulande, Virginie Bernard, Didier Decaudin, Florence Coussy, Muriel Le Romancer, Guillaume Dutertre, Zakia Tariq, Paul Cottu, Keltouma Driouch, Ivan Bièche, Lesley-Ann Martin, Elisabetta Marangoni

AbstractA significant proportion of patients with oestrogen receptor (ER) positive breast cancers (BC) develop resistance to endocrine treatments (ET) and relapse with metastatic disease. Here we perform whole exome sequencing and gene expression analysis of matched primary breast tumours and bone metastasis-derived patient-derived xenografts (PDX). Transcriptomic analyses reveal enrichment of the G2/M checkpoint and up-regulation of Polo-like kinase 1 (PLK1) in PDX. PLK1 inhibition results in tumour shrinkage in highly proliferating CCND1-driven PDX, including different RB-positive PDX with acquired palbociclib resistance. Mechanistic studies in endocrine resistant cell lines, suggest an ER-independent function of PLK1 in regulating cell proliferation. Finally, in two independent clinical cohorts of ER positive BC, we find a strong association between high expression of PLK1 and a shorter metastases-free survival and poor response to anastrozole. In conclusion, our findings support clinical development of PLK1 inhibitors in patients with advanced CCND1-driven BC, including patients progressing on palbociclib treatment.