Higher expression of genes involved in O -glycan synthesis in the carcinoma compared to the papillary adenocarcinoma tumors. KEGG pathway analysis was performed using DAVID software. Light gray background – significantly (P < 0.05) higher expression in carcinoma; gray background – no significant difference; frame around background – over twofold difference. The underlined letters C (carcinoma) or P (papillary adenocarcinoma) which follow the gene name indicate the type of tumor in which gene expression is exclusively different from the mammary gland. The direction of the arrows indicates the type of change (up- or downregulation). One arrow – statistically significant (P < 0.05) difference. Two arrows – statistically significant and over twofold difference.