Romidepsin and belinostat synergize the antineoplastic effect of bortezomib in mantle cell lymphoma

Luca Paoluzzi, Luigi Scotto, Enrica Marchi, Jasmine Zain, Venkatraman E. Seshan, Owen A. O'Connor

Research output: Contribution to journalArticle

52 Scopus citations


Purpose: Romidepsin and belinostat are inhibitors of histone deacetylases (HDACI). HDACIs are known to induce cell death in malignant cells through multiple mechanisms, including upregulation of death receptors and induction of cell cycle arrest. They are also known to be prodifferentiating. Mantle cell lymphoma (MCL) is an aggressive subtype of non-Hodgkin lymphoma characterized by the t(11;14) (q13;q32) translocation leading to the overexpression of cyclin D1. Experimental Design: Assays for cytotoxicty including mathematical analysis for synergism, flow-cytometry, immunoblottings, and a xenograft severe combined immunodeficient beige mouse model were used to explore the in vitro and in vivo activity of romidepsin and/or belinostat alone or in combination with the proteasome inhibitor bortezomib in MCL. Results: In vitro, romidepsin and belinostat exhibited concentration-dependent cytotoxicity against a panel of MCL cell lines. Both HDACI showed strong synergism when combined with the proteasome inhibitor bortezomib in MCL. An HDACI plus bortezomib also induced potent mitochondrial membrane depolarization and apoptosis, whereas no significant apoptosis was observed in peripheral blood mononuclear cells from healthy donors with the combination. These events were associated with a decrease in cyclin D1 and Bcl-XL, and an increase in accumulation of acetylated histone H3, acetylated α-tubulin, and Noxa in cell lines. In a severe combined immunodeficient beige mouse model of MCL, the addition of belinostat to bortezomib enhanced efficacy compared with either drug alone. Conclusions: Collectively, these data strongly suggest that HDACI such as romidepsin or belinostat in combination with a proteasome inhibitor could represent a novel and rationale platform for the treatment of MCL.

Original languageEnglish (US)
Pages (from-to)554-565
Number of pages12
JournalClinical Cancer Research
Issue number2
Publication statusPublished - Jan 15 2010
Externally publishedYes


ASJC Scopus subject areas

  • Oncology
  • Cancer Research

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