Drug Repositioning

of the Phenylpiperazine Derivative

Naftopidil in Prostate Cancer Treatment

8

Kenichiro Ishii, Yoshiki Sugimura, and Masatoshi Watanabe

Abstract

Naftopidil, a selective α1-adrenoceptor antagonist, is commonly used for the

treatment of benign prostatic hyperplasia, a prostatic disease occurring in elderly

men. In drug repositioning studies conducted from our laboratory, we

demonstrated that naftopidil has growth inhibitory effects by inducing G1 cell

cycle arrest in cancer cells, fibroblasts, and vascular endothelial cells. Moreover,

naftopidil has been shown to bind directly to and inhibit the polymerization of

tubulins; thus, naftopidil may exhibit general cytotoxicity in many types of cells.

Recent evidence has supported that additive naftopidil treatment in combination

with chemotherapy could be a new clinical application for the treatment of

prostate cancer.

Keywords

Prostate cancer · Naftopidil · Drug repositioning · Cell cycle · Phenylpiperazine-

based structure

K. Ishii (*)

Department of Oncologic Pathology, Mie University Graduate School of Medicine, Tsu, Mie, Japan

Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of

Medicine, Tsu, Mie, Japan

Department of Nursing, Nagoya University of Arts and Sciences, Nagoya, Aichi, Japan

e-mail: kenishii@med.mie-u.ac.jp; kenishii74@gmail.com; kenishii@nuas.ac.jp

Y. Sugimura

Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of

Medicine, Tsu, Mie, Japan

M. Watanabe

Department of Oncologic Pathology, Mie University Graduate School of Medicine, Tsu, Mie, Japan

# The Author(s), under exclusive license to Springer Nature Singapore Pte

Ltd. 2022

R. C. Sobti, N. S. Dhalla (eds.), Biomedical Translational Research,

https://doi.org/10.1007/978-981-16-9232-1_8

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