In vivocontrolled release and prolonged antitumor effects of 2-methoxyestradiol solid lipid nanoparticles incorporated into a thermosensitive hydrogel

In situ Hydrogels for Effective Treatment of Cancer: Strategies and Polymers Used

Cancer is a worldwide health ailment with no known boundaries in terms of mortality and occurrence rates, thus is one of the biggest threats to humankind. Hence, there is an absolute need to develop novel therapeutics to bridge the infirmities associated with chemotherapy and conventional surgical methodologies including impairment of normal tissue, compromised drug efficiency and an escalation in side effects. In lieu of this, there's been a surge in curiosity towards development of injectable hydrogels for cancer therapy because local administration of the active pharmaceutical agent offers encouraging advantages such as providing higher effective dose at target site, prolonged retention time of drug, ease of administration, mitigation of dose in vivo ,improved patient compliance. Furthermore, due to its biocompatible nature such systems can significantly reduce the side effects that occur on long-term exposure to chemotherapy. The present review details the most recent advancements in in-situ gel forming polymers (natural and synthetic), polymeric cross-linking methodologies and in-situ gelling mechanisms, focusing on their clinical benefits in cancer therapy.

Multiple local therapeutics based on nano-hydrogel composites in breast cancer treatment

The locoregional recurrence of breast cancer after tumor resection represents several clinical challenges, and conventional post-surgical adjuvant therapeutics always bring about significant systemic side effects. Thus, the local therapy strategy has received considerable interest in breast cancer treatment, and hydrogels can function as ideal platforms due to their remarkable properties such as good biocompatibility, biodegradability, flexibility, and multifunctionality. The nano-hydrogel composites can further incorporate the advantages of nanomaterials into the hydrogel system, to fabricate hierarchical structures for stimulating controlled multi-stage release of different therapeutic agents and improving the synergistic effects of combination therapy. In this review, the problems of clinical treatments of breast cancer and properties of hydrogels in current biomedical applications are briefly overviewed. The focus is on recent advances in local therapy based on nano-hydrogel composites for both monotherapy (chemotherapy, photothermal and photodynamic therapy) and combination therapy (dual chemotherapy, photothermal chemotherapy, photothermal immunotherapy, radio-chemotherapy). Moreover, the challenges and perspectives in the development of advanced nano-hydrogel systems are also discussed.

Availability of polymeric nanoparticles for specific enhanced and targeted drug delivery

Over the past 20–30 years there has been quite a number of studies interested in polymeric nanoparticle (PNP) systems as a pharmaceutical approach for poorly soluble drugs, peptide drugs, gene and antibodies. Now, the products based on the PNP technologies are used in the fields of medical science, pharmaceutical science, tissue engineering and clothing, food and housing. This review focuses attention on PNPs for specific enhanced and targeted drug delivery of therapeutic drugs including peptide drugs as well as drug delivery applications of such systems. Outcomes from recent studies on polymers, how to make PNPs, pharmacokinetics and pharmacodynamics of PNPs, and the release profiles from PNPs and related systems are also described, including their pharmacokinetics and pharmacodynamics, if available. In addition, the latest PNP trends and will be described.

Prostate carcinoma cell growth-inhibiting hydrogel supports axonal regeneration in vitro

Prostate cancer is the most common malignant tumor in men. Radical prostatectomy, the most common surgical therapy, is typically accompanied by erectile dysfunction and incontinence due to severing of the axons of the plexus prostaticus. To date, no reconstructive therapy is available as the delicate network of severed nerve fibers preclude the transplantation of autologous nerves or synthetic tube implants. Here, we present an injectable hydrogel as a regenerative matrix that polymerizes in situ and thus, adapts to any given tissue topography. The two-component hydrogel was synthesized from a hydrolyzed collagen fraction and stabilized by enzymatic crosslinking with transglutaminase. Physical analysis employing osmolarity measurements and cryosectioning revealed an isotonic, microstructured network that polymerized within 2min and displayed pronounced adhesion to abdominal tissue. Cell culturing demonstrated the biocompatibility of the gel and a general permissiveness for various neuronal and non-neuronal cell types. No effect on cell adhesion, survival and proliferation of cells was observed. A chemotherapeutic drug was integrated into the hydrogel to reduce the risk of fibrosis and tumor relapse. Significantly, when the hydrogel was employed as a drug release depot in vitro, aversive fibroblast- and prostate carcinoma cell growth was inhibited, while axonal outgrowth from peripheral nervous system explants remained completely unaffected. Taken together, these results suggest that the gel's adequate viscoelastic properties and porous microstructure, combined with its tissue adhesion and neuritotrophic characteristics in the presence of a cell type-specific cytostatic, may constitute an appropriate hydrogel implant applicable to patients suffering from prostatectomy associated side effects.