Galanin receptor subtype 2 suppresses cell proliferation and induces apoptosis in p53 mutant head and neck cancer cells.

Abstract

Galanin and its three receptors (GALR1-3) are expressed in many normal tissues, but silenced in some tumors. Contradictory roles for galanin and its receptors in various tumors have been reported. To understand their function, investigations of individual galanin receptors are necessary. In head and neck squamous carcinoma cells (HNSCC) with silenced GALR1 and GALR2, we showed that reexpressed GALR1 suppresses tumor cell proliferation via Erk1/2-mediated effects on cdk inhibitors and cyclin D1. Others showed that GALR2 could induce apoptosis in neuroblastoma cells with wild-type p53, whereas GALR2 stimulated proliferation in small cell lung cancer. In this study, we investigated the role of GALR2 in HNSCC cells that have mutant p53 and do not express GALR1.