The glycome of one of the largest and most exposed human organs, the skin, as well as
glycan changes associated with non-
melanoma skin cancers have not been studied in detail to date.
Skin cancers such as
basal cell carcinoma (BCC) and
squamous cell carcinoma (SCC) are among the most frequent types of
cancers with rising incidence rates in the aging population. We investigated the healthy human skin N- and O-glycome and its changes associated with BCC and SCC. Matched patient samples were obtained from frozen biopsy and
formalin-fixed
paraffin-embedded tissue samples for glycomics analyses using two complementary glycomics approaches: porous graphitized
carbon nano-liquid chromatography electro spray ionization tandem mass spectrometry and capillary gel electrophoresis with
laser induced fluorescence detection. The human skin N-glycome is dominated by complex type N-
glycans that exhibit almost similar levels of α2-3 and α2-6 sialylation.
Fucose is attached exclusively to the N-
glycan core. Core 1 and core 2 type O-
glycans carried up to three
sialic acid residues. An increase of oligomannose type N-
glycans and core 2 type O-
glycans was observed in BCC and SCC, while α2-3 sialylation levels were decreased in SCC but not in BCC. Furthermore,
glycopeptide analyses provided insights into the
glycoprotein candidates possibly associated with the observed N-
glycan changes, with
glycoproteins associated with binding events being the most frequently identified class.