Specific Binding of D-Amino Neuraminic Acid To Ganglioside Studied in Prostate Cancer Cells

Abstract

Aim: The aim of this study was to investigate the cellular binding site of human D-Amino Neuraminic Acid (KDN, 2-keto-3-deoxy-D-glycero-D-galacto-nononic acid). The KDN molecule is a member of the sialic acid family, and its expression increases in cancer cells. KDN has been shown to bind to Monosialodihexosyl Ganglioside (GM3) in trout sperm. Materials and Methods: In this study, a prostate cancer cell line (DU145) was used. Each experimental group was divided into 3 groups: Control, Glucosylceramide synthase (GCS) enzyme inhibitor Genz-123346-treated, and GM3 synthesis inhibitor Triptolide-treated. Each group was stained using the immunocytochemical method for GM3, Disialosyllactosylceramide (GD3) and KDN. Fourier Transform Infrared (FTIR) Spectroscopy analysis was performed to elucidate the cellular changes after treatment. Results: The group of non-treated number 1 cells stained positive with GM3, GD3 and KDN, and the GCS enzyme was blocked with the Genz-123346 group of number 2 cells stained positive only with KDN. Furthermore, the group of GD3 synthase inhibitor Triptolide treated number 3 cells stained positive with GM3 and KDN. FTIR measurements showed apoptotic characteristics with Triptolide, while Genz-123346 did not have a negative effect on cell viability. There was a reduction in sugar structures and the results obtained with immunocytochemical staining were reinforced with FTIR. Conclusions: Determining the location of the bound KDN is important for the selection of new targets for cancer treatment research. KDN has been shown to be not inhibited by GM3 inhibition and GD3 inhibition. KDN can be on GM3 as well as connected to different places or can be free. In this study, it was demonstrated that it would not bind to any of the gangliosides in the pure GM or GD series.