Targeted inhibition of Hedgehog-GLI signaling by novel acylguanidine derivatives inhibits melanoma cell growth by inducing replication stress and mitotic catastrophe.

Abstract

Aberrant activation of the Hedgehog (HH) signaling is a critical driver in tumorigenesis. The Smoothened (SMO) receptor is one of the major upstream transducers of the HH pathway and a target for the development of anticancer agents. The SMO inhibitor Vismodegib (GDC-0449/Erivedge) has been approved for treatment of basal cell carcinoma. However, the emergence of resistance during Vismodegib treatment and the occurrence of numerous side effects limit its use. Our group has recently discovered and developed novel and potent SMO inhibitors based on acylguanidine or acylthiourea scaffolds. Here, we show that the two acylguanidine analogs, compound (1) and its novel fluoride derivative (2), strongly reduce growth and self-renewal of melanoma cells, inhibiting the level of the HH signaling target GLI1 in a dose-dependent manner. Both compounds induce apoptosis and DNA damage through the ATR/CHK1 axis. Mechanistically, they prevent G2 to M cell cycle transition, and induce signs of mitotic aberrations ultimately leading to mitotic catastrophe. In a melanoma xenograft mouse model, systemic treatment with 1 produced a remarkable inhibition of tumor growth without body weight loss in mice. Our data highlight a novel route for cell death induction by SMO inhibitors and support their use in therapeutic approaches for melanoma and, possibly, other types of cancer with active HH signaling.

• Authors: Silvia Pietrobono, Roberta Santini, Sinforosa Gagliardi, Francesca Dapporto, David Colecchia, Mario Chiariello, Cosima Leone, Massimo Valoti, Fabrizio Manetti, Elena Petricci, Maurizio Taddei, Barbara Stecca
• Journal: Cell death & disease (Cell Death Dis) Vol. 9 Issue 2 Pg. 142 (02 02 2018) ISSN: 2041-4889 [Electronic] England
• PMID: 29396391 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Guanidines
• Hedgehog Proteins
• Smoothened Receptor
• Zinc Finger Protein GLI1

Topics

• Animals
• Apoptosis (drug effects)
• Cell Cycle Checkpoints (drug effects)
• Cell Line, Tumor
• Cell Proliferation (drug effects)
• Cell Self Renewal
• Cell Survival (drug effects)
• DNA Damage
• DNA Replication (drug effects)
• Female
• Guanidines (pharmacology)
• Hedgehog Proteins (metabolism)
• Humans
• Inhibitory Concentration 50
• Melanoma (pathology)
• Mice, Nude
• Mitosis (drug effects)
• Neoplastic Stem Cells (drug effects, metabolism, pathology)
• Signal Transduction
• Smoothened Receptor (metabolism)
• Stress, Physiological
• Xenograft Model Antitumor Assays
• Zinc Finger Protein GLI1 (metabolism)