Anti-tumoral effect of desmethylclomipramine in lung cancer stem cells.

Abstract

Lung cancer is the most feared of all cancers because of its heterogeneity and resistance to available treatments. Cancer stem cells (CSCs) are the cell population responsible for lung cancer chemoresistance and are a very good model for testing new targeted therapies. Clomipramine is an FDA-approved antidepressant drug, able to inhibit in vitro the E3 ubiquitin ligase Itch and potentiate the pro-apoptotic effects of DNA damaging induced agents in several cancer cell lines. Here, we investigated the potential therapeutic effect of desmethylclomipramine (DCMI), the active metabolite of Clomipramine, on the CSCs homeostasis. We show that DCMI inhibits lung CSCs growth, decreases their stemness potential and increases the cytotoxic effect of conventional chemotherapeutic drugs. Being DCMI an inhibitor of the E3 ubiquitin ligase Itch, we also verified the effect of Itch deregulation on CSCs survival. We found that the siRNA-mediated depletion of Itch induces similar anti-proliferative effects on lung CSCs, suggesting that DCMI might exert its effect, at least in part, by inhibiting Itch. Notably, Itch expression is a negative prognostic factor in two primary lung tumors datasets, supporting the potential clinical relevance of Itch inhibition to circumvent drug resistance in the treatment of lung cancer.

• Authors: Lucilla Bongiorno-Borbone, Arianna Giacobbe, Mirco Compagnone, Adriana Eramo, Ruggero De Maria, Angelo Peschiaroli, Gerry Melino
• Journal: Oncotarget (Oncotarget) Vol. 6 Issue 19 Pg. 16926-38 (Jul 10 2015) ISSN: 1949-2553 [Electronic] United States
• PMID: 26219257 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents
• Repressor Proteins
• desmethylclomipramine
• ITCH protein, human
• Ubiquitin-Protein Ligases
• Clomipramine

Topics

• Adenocarcinoma (genetics, mortality, pathology)
• Antineoplastic Agents (pharmacology)
• Blotting, Western
• Cell Line, Tumor
• Cell Proliferation (drug effects)
• Cells, Cultured
• Clomipramine (analogs & derivatives, pharmacology)
• Drug Resistance, Neoplasm (drug effects)
• Flow Cytometry
• Humans
• Kaplan-Meier Estimate
• Lung Neoplasms (genetics, mortality, pathology)
• Neoplastic Stem Cells (drug effects)
• RNA Interference
• Repressor Proteins (genetics)
• Ubiquitin-Protein Ligases (genetics)