Bladder cancer (BC) is a complex disease with multiple clinical manifestations and treatment challenges, and current standard-of-care therapies remain limited and unfavorable. Theranostics, the integration of diagnostic and therapeutic technologies, has emerged as a promising strategy to address these challenges. The rapid development of nanomedicine has been a source of hope for the improvement of BC therapies and diagnostics by reducing side effects, enhancing tumor suppression, and overcoming drug resistance. Metal nanoparticles (NPs), inorganic NPs, polymer NPs, etc. have their respective advantages and show encouraging potential in the therapy of BC. In this review, we provide an overview on the state of the art in nanotechnology-based theranostics for BC, offering insights into the design and discovery of novel NPs for future BC management.

It is widely acknowledged that sialyl Lewis X (sLeX), the composition and linkage of which are N-acetylneuraminic acid (Neu5Ac) α2-3 galactose (Gal) β1-4 [fucose (Fuc) α1-3] N-acetylglucosamine, is usually attached to the cell surface. It presents as a terminal structure on either glycoproteins or glycolipids and has been demonstrated to be related to various biological processes, such as fertilization and selectin binding. Due to the vital role of sLeX, its synthesis as well as its determination approaches have attracted considerable attention from many researchers. In this review, the focus is sLeX on glycoproteins. The biological importance of sLeX in fertilization and development, immunity, cancers, and other aspects will be first introduced. Then the chemical and enzymatic synthesis of sLeX including the contributions from more than 15 international research groups will be described, followed by a brief view of the sLeX detection focusing on monosaccharides and linkages. This review is valuable for those readers who are interested in the chemistry and biology of sLeX.