ABSTRACT
Ferroptosis is a novel type of iron-dependent non-apoptotic pathway that regulates cell death and shows unique mechanisms including causing lipid peroxide accumulation, sensitizing drug-resistant cancers, priming immunity by immunogenic cell death, and cooperatively acting with other anticancer modalities for eradicating aggressive malignancies and tumor relapse. Recently, there has been a great deal of effort to design and develop anticancer biocompatible polymeric nanoplatforms including polypeptide and PEGylated ones to achieve effective ferroptosis therapy (FT) and synergistic combination therapies including chemotherapy (CT), photodynamic therapy (PDT), sonodynamic therapy (SDT), photothermal therapy (PTT), gas therapy (GT) including nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H2 S), and immunotherapy (IT). To be noted, the combo therapies such as FT-CT, FT-PTT, FT-GT, and FT-IT are attracting much efforts to fight against intractable and metastatic tumors as they can generate synergistic antitumor effects and immunogenic cell death (ICD) effects or modulate immunosuppressive tumor microenvironments to initiate strong antitumor immunity and memory effects. The polymeric Fenton nano-agents with good biosafety and high anticancer efficacy will provide a guarantee for their applications. In this review, various biocompatible polymer-modified nanoplatforms designed for FT and combo treatments are summarized for anticancer therapies and discussed for potential clinical transitions.
Subject(s)
Ferroptosis , Nanoparticles , Neoplasms , Photochemotherapy , Humans , Combined Modality Therapy , Immunotherapy , Polymers , Cell Line, Tumor , Neoplasms/drug therapy , Nanoparticles/therapeutic use , Tumor MicroenvironmentABSTRACT
Two-step anodization has been widely used because it can produce highly self-organized anodic TiO2nanotubes, but the differences in morphology and current-time curve of one-step anodization and two-step anodization are rarely reported. Here, one-step anodization and two-step anodization were conducted at different voltages. By comparing the FESEM image of anodic TiO2nanotubes fabricated by one-step anodization and two-step anodization, it was found that the variation of morphology characteristics is same with voltage. The distinction of morphology and current-time curve between one-step anodization and two-step anodization at the same voltage were analyzed: the nanotube average growth rate and porosity of two-step anodization are greater than that of one-step anodization. In the current-time curve, the duration of stage I and stage II in two-step anodization are significantly shorter than one-step anodization. The traditional field-assisted dissolution theory cannot explain the three stages of the current-time curves and their physics meaning under different voltages in the same fluoride electrolyte. Here, the distinction between one-step anodization and two-step anodization was clarified successfully by the theories of ionic current and electronic current and oxygen bubble mould.
