Neuromedin B receptor antagonist suppresses tumor angiogenesis and tumor growth in vitro and in vivo

School of Dentistry, Pusan National University, Yangsan 626-870, South Korea.
Cancer letters (Impact Factor: 5.62). 08/2011; 312(1):117-27. DOI: 10.1016/j.canlet.2011.08.014
Source: PubMed


Neuromedin B (NMB), a member of the mammalian bombesin-like peptide family, and its receptor were aberrantly expressed in vascularized solid tumors. Here, the NMB receptor (NMB-R) antagonist PD168368 specifically inhibited both NMB-induced in vivo and in vitro angiogenesis. In addition, PD168368 showed growth inhibitory effects on MDA-MB-231 breast cancer cells by inducing cell cycle arrest and apoptosis. Furthermore, PD168368 effectively suppressed tumor growth in a xenograft model of breast tumor in vivo. Overall, NMB-R antagonist exhibited a significant antitumor activity by simultaneously inhibiting neovascularization and cancer cell growth, thereby suggesting that NMB-R could be a potential therapeutic target for cancer treatment.

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    • "Several lines of evidence indicate that mammalian bombesin-like peptide receptors, including the GRP and NMB receptors, are frequently overexpressed by a variety of tumor cell lines and tumor specimens from patients with lung, colorectal, gastric, prostate, and breast cancers [8,10,25-27]. Overexpression of bombesin-like peptide receptors promotes tumor development and progression by stimulating cancer cell proliferation and migration [28-30]. Recently, targeting GRP receptor (GRP-R) represents a useful therapeutic strategy to treat some human malignancies [31,32]. "
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