Journal of Oncology Translational Research

Detection and Characterization by Immunohistochemistry of the NGcGM3 Ganglioside in the Chicken Animal Model of Ovarian Cancer

Abstract

Angel Casaco Parada, Addy Gonzalez Palomo, Dale Buchanan Hales, Karen Hales and Luis Enrique Fernandez

In spite of ovarian cancer mortality rates have tended to level off and decrease during the last years in several countries, the disease is still the gynecological cancer with the highest death rate. The current therapies for ovarian cancer include surgery and chemotherapy based on platinum and a taxane. Nevertheless, these therapies are only efficient at the first stages of the disease and the treatments are lack of specificity, further contributing to the high mortality rates of ovarian cancer. The adult laying hen is a very interesting model for studying the development of the epithelial ovarian cancer since hen develops intense ovulation, spontaneous ovarian cancers and metabolic progression similar to women. It is known that normal chicken cells and human cells have no metabolic pathway for NeuGc biosynthesis due to a partial deletion in the gene that encodes CMP-Neu5Ac hydroxylase. Gangliosides are interesting type of molecules, different from proteins that have been identified as tumor antigens. Mammalian cells have these types of glycosphingolipids on their plasmatic membranes. Due to gangliosides are over-expressed in many tumors compared with the corresponding normal tissues, they are considered as very attractive compounds for immunotherapy, attributing to them a very important role in the growth and metastatic tumor processes. The aim of this study is to elucidate by immunohistochemistry the existence of NeuGc-GM3 in hen ovarian cancers. Slides with normal and cancer ovarian tissues from 3.5 years old chickens were incubated with the very specific anti- NeuGcGM3 ganglioside 14F7 Mab for immunohistochemical studies. These studies showed that the 14F7 Mab immunorecognition was mainly evidenced in epithelial ovarian tumors and not in normal tissues. The presence of NeuGc-containing gangliosides in chicken and human epithelial ovarian cancers makes the chicken an interesting and relevant animal model for further experimental and translational investigations on ganglioside based immunotherapy.