Biomedicine is constantly evolving to ensure a significant and positive impact on healthcare, which has resulted in innovative and distinct requisites such as hydrogels. Chitosan-based formulations stand out for their versatile utilization in drug encapsulation, transport, and controlled release, which is complemented by their biocompatibility, biodegradability, and non-immunogenic nature. Stimuli-responsive hydrogels, also known as smart hydrogels, have strictly regulated release patterns since they respond and adapt based on various external stimuli. Moreover, they can imitate the intrinsic tissues’ mechanical, biological, and physicochemical properties. These characteristics allow stimuli-responsive hydrogels to provide cutting-edge, effective, and safe treatment. Constant progress in the field necessitates an up-to-date summary of current trends and breakthroughs in the biomedical application of stimuli-responsive chitosan-based hydrogels, which was the aim of this review. General data about hydrogels sensitive to ions, pH, redox potential, light, electric field, temperature, and magnetic field are recapitulated. Additionally, formulations responsive to multiple stimuli are mentioned. Focusing on chitosan-based smart hydrogels, their multifaceted utilization was thoroughly described. The vast application spectrum encompasses neurological disorders, tumors, wound healing, and dermal infections. Available data on smart chitosan hydrogels strongly support the idea that current approaches and developing novel solutions are worth improving. The present paper constitutes a valuable resource for researchers and practitioners in the currently evolving field.

This comprehensive review examines the therapeutic potential of metformin, a well-established diabetes medication, in treating neurodegenerative disorders. Originally used as a first-line treatment for type 2 diabetes, recent studies have begun investigating metformin’s effects beyond metabolic disorders, particularly its neuroprotective capabilities against conditions like Parkinson’s disease, Alzheimer’s disease, Huntington’s disease, and multiple sclerosis. Key findings demonstrate that metformin’s neuroprotective effects operate through multiple pathways: AMPK activation enhancing cellular energy metabolism and autophagy; upregulation of antioxidant defenses; suppression of inflammation; inhibition of protein aggregation; and improvement of mitochondrial function. These mechanisms collectively address common pathological features in neurodegeneration and neuroinflammation, including oxidative stress, protein accumulation, and mitochondrial dysfunction. Clinical and preclinical evidence supporting metformin’s association with improved cognitive performance, reduced risk of dementia, and modulation of pathological hallmarks of neurodegenerative diseases is critically evaluated. While metformin shows promise as a therapeutic agent, this review emphasizes the need for further investigation to fully understand its mechanisms and optimal therapeutic applications in neurodegenerative diseases.

Background/Objectives: AP-2 transcription factors are increasingly recognized as key regulators in cancer biology. The TFAP2E gene, which encodes the AP-2ε transcription factor, remains understudied in cancer compared with other AP-2 family members. The scarcity of studies examining potential AP-2ε targets and related genes limits our understanding of its functional significance. Moreover, related studies have not incorporated a screening step to select the tumor type for justified molecular investigation. Through comparison of tumor–normal expression differences in a pan-cancer spectrum, this study prioritized ovarian serous carcinoma for downstream assessment. Methods: Expression patterns were evaluated using GENT2, GEPIA2, and TNMplot. After prioritizing ovarian serous carcinoma, TFAP2E and related signatures in TCGA-OV were analyzed using transcriptomic and clinical data from GDC and CDR, followed by comparison of findings with the GSE32062 cohort. The workflow included survival and clinicopathological analyses, outcome-independent limma-voom differential expression analysis and WGCNA, MCODE clustering, gene ontology, immune subtype and stemness assessment, PCA, CancerHallmarks enrichment, clinically adjusted Cox and competing-risk survival modeling, and HPA-derived immunostaining evaluation. Additional analyses assessed WGCNA parameter stability and preservation in GSE32062, an outcome-independent MAD-based variability screen, AP-2 family coexpression, and promoter motif enrichment. Results: TFAP2E was downregulated in ovarian cancer across the three queried resources, whereas higher expression was associated with favorable survival across multiple endpoints. Differential expression and WGCNA identified a TFAP2E-associated signature; its ontology indicated GPCR, stimulus responsiveness, and KRAS enrichment for the 933-gene module. The WGCNA pink module was stable across alternative settings, moderately preserved in GSE32062 (Zsummary = 7.86), and enriched in the outcome-independent MAD screening. GSE32062 supported concordant gene expression patterns and showed an association of TFAP2E with progression-free survival. Exploratory immune analyses showed a modestly increased proportion of C5 tumors in the higher-expression groups, whereas differences in stemness were statistically insignificant. The TFAP2E group associations with PFI and DSS in TCGA-OV and with PFS in GSE32062 remained significant after clinical adjustment; Fine-Gray sensitivity analyses gave consistent results for DSS. Immunohistochemistry provided protein-level characterization; eighteen entries differed between representative normal and tumor specimens, with lower tumor staining in fifteen. The seven-gene candidate set showed a clinically adjusted DSS association in TCGA-OV, which was not supported in the GSE32062 evaluation model. Conclusions: TFAP2E expression is associated with survival and a transcriptomic cross-cohort pattern in ovarian serous carcinoma. Covariate-adjusted and competing-risk analyses supported the association but did not establish clinical utility. The highlighted genes remain exploratory candidates for mechanistic investigation.