Rheumatoid arthritis is a sysrenmic autoimmune disease which mainly affects joints that affects millions of patients in the world. Protein therapeutic is one of the important treatment against this disease. In order to perform precised protien delivery, engineered exosomes are significant tools. This review includes the pathophysiology of rheumatoid arthritis and therapeutic targets, introduction of exosomes, strategies of engineering exosomes and the evaluation of engineered exosome-based protein drug delivery systems. The research shows that exosome is a good material for target protein delivery due to its accuracy and biocompatibility. The efficiency is significantly increased comparing with other delivery system. However, there are still some limitation for this method, such as high cost and low cargo loading efficiency. This review calls for the medical industry's attention on this kind of new technique to improve the engineeringf strategies and reduce the costs, in order to put this method in use for more patients.

Cancer is still a major cause of death worldwide, and the old ways of treating cancer have defects, such as systemic toxicity, quick drug resistance, and poor targeting. Given the favorable features of the tumour microenvironment, conventional therapy has shown limited efficacy, thus, new nanocarrier-based drug delivery systems are needed. This review will introduce the necessary biological and physical characteristics of the tumour microenvironment and present current responsive nanoparticle platforms, such as lipid-based, polymer-based, inorganic, biological, and hybrid systems, associated with their construction patterns, therapeutic effects, and preclinical progress. Preclinical data show that these nanocarriers improve tumour accumulation and realise controlled, localised drug release. However, clinical translation still faces many problems, such as poor manufacturing feasibility, unstable circulation, extended-term biosafety risks, tumour heterogeneity, and a lack of standardised evaluation systems. Another reason is that the preclinical model may not be in the same environment as a person. The following are some promising directions for this paper: multimodal analysis, optimisation with additional data from artificial intelligence (AI), and descendant models of patients. The above ways can help to solve the problems caused by translation and provide new directions for the development of cancer therapy.

Skin aging is a complicated biological process that is associated with structural and functional progressive degradation; one of its core driving mechanisms is the disruption of epigenetic regulation. Among potential anti-aging intervention strategies, partial reprogramming has attracted widespread attention recently. It aims to reverse the epigenetic state of senescent cells towards a younger direction while not eliminating each specialized identity of cells. This paper systematically illustrates the research progress of epigenetic partial reprogramming in rejuvenating skin aging. Starting from the mechanism connection between epigenetic erosion and cellular identity loss, it analyses the experimental evidence in animal models, in human fibroblasts, and in vitro skin tissues, while emphasizing the crucial obstacles when translating this technology to clinical use. Current findings indicate that partial reprogramming is capable of reversing aging-related epigenetic markers while, to some extent, recovering some cellular functions, such as collagen synthesis, migration ability, and extracellular matrix remodeling, etc. However, all this evidence stems from preclinical investigation, yet has not been fully verified in terms of the safety, persistence, and functional significance of reprogramming effects in intact human skin. This review concludes that partial reprogramming has potential as an experimental strategy, but whether it could be developed into a real clinically feasible intervention depends on whether future investigation could gain substantive breakthroughs in terms of precisely controlling the intensity of reprogramming, maintaining cell identity, ensuring long-term safety, and achieving tissue-specific delivery..