title: Apicidin and docetaxel combination treatment drives CTCFL expression and HMGB1 release acting as potential antitumor immune response inducers in metastatic breast cancer cells.
abstract: Currently approved combination regimens available for the treatment of metastatic tumors, such as breast cancer, have been shown to increase response rates, often at the cost of a substantial increase in toxicity. An ideal combination strategy may consist of agents with different mechanisms of action leading to complementary antitumor activities and safety profiles. In the present study, we investigated the effects of the epigenetic modulator apicidin in combination with the cytotoxic agent docetaxel in tumor breast cell lines characterized by different grades of invasiveness. We report that combined treatment of apicidin and docetaxel, at low toxicity doses, stimulates in metastatic breast cancer cells the expression of CTCF-like protein and other cancer antigens, thus potentially favoring an antitumor immune response. In addition, apicidin and docetaxel co-treatment specifically stimulates apoptosis, characterized by an increased Bax/Bcl-2 ratio and caspase-8 activation. Importantly, following combined exposure to these agents, metastatic cells were also found to induce signals of immunogenic apoptosis such as cell surface expression of calreticulin and release of considerable amounts of high-mobility group box 1 protein, thus potentially promoting the translation of induced cell death into antitumor immune response. Altogether, our results indicate that the combined use of apicidin and docetaxel, at a low toxicity profile, may represent a potential innovative strategy able to activate complementary antitumor pathways in metastatic breast cancer cells, associated with a potential control of metastatic growth and possible induction of antitumor immunity.
authors.affiliation: Department of Hematology, Oncology and Molecular Medicine, Istituto Superiore di Sanita, 00161 Rome, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Buoncervello
authors.forename: Paola
authors.initials: P
authors.lastname: Borghi
authors.forename: Giulia
authors.initials: G
authors.lastname: Romagnoli
authors.forename: Francesca
authors.initials: F
authors.lastname: Spadaro
authors.forename: Filippo
authors.initials: F
authors.lastname: Belardelli
authors.forename: Elena
authors.initials: E
authors.lastname: Toschi
authors.forename: Lucia
authors.initials: L
authors.lastname: Gabriele
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects / Q000276:immunology; D001943:Breast Neoplasms / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000276:immunology; D003713:Dendritic Cells / Q000187:drug effects / Q000276:immunology; D000077143:Docetaxel; D004357:Drug Synergism; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D024243:HMGB1 Protein / Q000235:genetics* / Q000276:immunology; D006801:Humans; D056747:Immunomodulation / Q000187:drug effects; D009362:Neoplasm Metastasis; D010456:Peptides, Cyclic / Q000008:administration & dosage / Q000494:pharmacology*; D043823:Taxoids / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: C456540:CTCFL protein, human; D004268:DNA-Binding Proteins; D024243:HMGB1 Protein; D010456:Peptides, Cyclic; D043823:Taxoids; C102351:apicidin; D000077143:Docetaxel