Nucleic acid therapeutics are emerging as a promising class of medicines, offering unique therapeutic options for cancer at the gene level. However, the druggability of nucleic acid therapeutics is fundamentally restricted by their low stability, poor membrane permeability, and low bioavailability, necessitating the use of delivery vectors. Various delivery vectors have been developed for nucleic acid therapeutics. The fate of established nucleic acid delivery systems (NADS) in vivo substantially affects the delivery efficiency and therapeutic efficacy. The physicochemical properties of NADS (such as size, charge, shape, etc) are crucial for the interaction of NADS with various biological barriers in the body, thereby determining the fate of NADS in the body. Nanoparticle (NP) size is an important parameter defining the blood circulation, distribution, tumor accumulation, and cellular uptake of NADS. This mini-review briefly introduces the various biological barriers of NADS in cancer treatment and focuses on the influence of the particle size of delivery vectors on the in vivo fate of NADS and their therapeutic efficacy, which provides new insights into the rational design of NADS.

With the continuous development of nanomaterials, nanofibers prepared by electrospinning have gradually occupied people’s vision because of their unique advantages, such as crisscross network and extracellular matrix-mimicking structure, high drug loading efficiency, and sustained release kinetics. Traditionally, electrospun fibers are mainly used as filter materials, wound dressings, and tissue engineering scaffolds, while their wide applications are limited to cancer nanomedicine applications due to their dense network structure. In recent years, two-dimensional fiber membranes have been transformed into short fibers that can be reconstructed to form fibrous rings or microspheres for cancer theranostics. Herein, this paper provides an overview of the recent advances in the design of electrospun short fibers that retain the advantages of nanofibers with good dispersibility for different nanomedicine applications, including cancer cell capture, cancer treatments, and cancer theranostics. The rational preparation of electrospun short fibers that are available to boost the development of nanomedicine is also discussed.

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.