Sialyl-di-Lewis (SdiLe)

Sialyl-di-Lewis refers to a class of complex tumor-associated carbohydrate antigens (TACAs), primarily Sialyl-di-Lewis a (SdiLea) and Sialyl-di-Lewis x (SdiLex), which are overexpressed on the surface of various malignant cells. These molecules are sialylated and fucosylated glycans that play critical roles in cell-cell recognition, adhesion, and the metastatic spread of tumors by acting as ligands for selectins. Sialyl-di-Lewis a is particularly significant as a therapeutic target in gastrointestinal, pancreatic, and colorectal cancers, where it is found on glycoproteins and associated with poor clinical outcomes. Unlike the related CA19-9 antigen, Sialyl-di-Lewis a exhibits a more restricted distribution in normal tissues, making it a highly specific target for immunotherapy. Current drug development efforts include monoclonal antibodies like FG129 and its chimeric version CH129, as well as antibody-drug conjugates designed to deliver cytotoxic agents directly to tumor cells. Additionally, Sialyl-di-Lewis x is known to mediate the adhesion of Helicobacter pylori to the gastric mucosa and is a target for selectin inhibitors in inflammatory diseases. These antigens function as biomarkers for cancer diagnosis and monitoring, with high expression levels often correlating with advanced disease stages. Overall, they represent a promising avenue for selective cancer therapy due to their high tumor specificity and functional involvement in malignancy.

Other names

Sialyl-di-Lewis aSialyl-di-Lewis xSdiLeaSdiLexSialyl-dimeric-Lewis aSialyl-dimeric-Lewis xTumor-associated carbohydrate antigen (TACA)

Antibody-dependent cellular cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), targeted delivery of cytotoxic payloads, and inhibition of selectin-mediated cell adhesion.