Detection of N-Glycolyl GM3 Ganglioside in Neuroectodermal Tumors by Immunohistochemistry: An Attractive Vaccine Target for Aggressive Pediatric Cancer

Abstract

The N-glycolylated ganglioside NeuGc-GM3 has been described in solid tumors such as breast carcinoma, nonsmall cell lung cancer, and melanoma, but is usually not detected in normal human cells. Our aim was to evaluate the presence of NeuGc-GM3 in pediatric neuroectodermal tumors by immunohistochemistry. Twenty-seven archival cases of neuroblastoma and Ewing sarcoma family of tumors (ESFT) were analyzed. Formalin-fixed, paraffin-embedded tumor samples were cut into 5 μm sections. The monoclonal antibody 14F7, a mouse IgG1 that specifically recognizes NeuGc-GM3, and a peroxidase-labeled polymer conjugated to secondary antibodies were used. Presence of NeuGc-GM3 was evident in 23 of 27 cases (85%), with an average of about 70% of positive tumors cells. Immunoreactivity was moderate to intense in most tumors, showing a diffuse cytoplasmic and membranous staining, although cases of ESFT demonstrated a fine granular cytoplasmic pattern. No significant differences were observed between neuroblastoma with and without NMYC oncogene amplification, suggesting that expression of NeuGc-GM3 is preserved in more aggressive cancers. Until now, the expression of N-glycolylated gangliosides in pediatric neuroectodermal tumors has not been investigated. The present study evidenced the expression of NeuGc-GM3 in a high proportion of neuroectodermal tumors, suggesting its potential utility as a specific target of immunotherapy.

Differential expression profiles of glycosphingolipids in human breast cancer stem cells vs. cancer non-stem cells

“…Aberrant expression of carbohydrate structures in cancer, including GSLs, has been known for decades (61,62), and GSLs in tumor cells have been shown to change their structure and organization in the membrane to promote tumor progression (60). In addition to GSLs indicated to be associated with CSCs in this study, the following were found to be highly expressed in human cancer but either absent or present in negligible amounts in normal cells/tissues: (i) blood group A-like antigens expressed in tumor cells of blood group O or B patients [the structure is GalNAcα1-O-Ser/Thr, termed Tn (63)(64)(65); (ii) sialyl 2-6Tn antigen [i.e., NeuAcα2-6GalNAcα1-O-Ser/Thr (66)]; and (iii) extended type-I antigen [i.e., Le a on Le a (67) or Le b on Le a (68,69)].…”

Immunoreactivity of the 14F7 Mab raised against N‐Glycolyl GM3 Ganglioside in retinoblastoma tumours

“…With this score, we could classify tumours in positive and negative for the expression of NeuGc-GM3. Positive tumours were considered when the score value was at or above 5 that was the cut-off, being negatives those under this value (Scursoni et al 2011). …”

“…This variant contains glycolylated sialic acid, which is not detected in normal human tissues and fluids, including the healthy retina (Higashi et al 1988;Marquina et al 1996;Scursoni et al 2010Scursoni et al , 2011Blanco et al 2011Blanco et al , 2012Blanco et al , 2013Zhong et al 2012;Lahera et al 2014). Human cells lack of the enzyme cytidine monophospho-N-acetylneuraminic acid hydroxylase, which regulates its synthesis (Irie & Suzuki 1998;Malykh et al 2001).…”

“…Human cells lack of the enzyme cytidine monophospho-N-acetylneuraminic acid hydroxylase, which regulates its synthesis (Irie & Suzuki 1998;Malykh et al 2001). The limited expression of NeuGc-GM3 in human normal tissues, as well as its presence in different tumours, indicates that this variant of GM3 could be a good candidate for immunotherapy to different tumours (Neninger et al 2007;Fernandez et al 2010;Scursoni et al 2011). Thus, the 14F7 antibody that recognises this epitope represents a promising alternative to immunotherapy treatments.…”

“…Thus, the 14F7 antibody that recognises this epitope represents a promising alternative to immunotherapy treatments. Using the 14F7 antibody, our group reported that neuroblastoma and other neuroectodermic tumours express NeuGc-GM3 in a high proportion of cases (Scursoni et al 2010(Scursoni et al , 2011. There is limited published evidence reporting the presence of NeuGc-GM3 in retinoblastoma cell lines (Higashi et al 1988), and none of these studies has evaluated its expression and cell distribution on histopathological grounds in different disease stages and clinical situations.…”