Rice bran is rich in bioactive compounds, but its potential for cosmeceutical applications remains insufficiently explored. In this study, we investigated the anti-melanogenic effects of a 70% ethanol extract of rice bran prepared by ultrasonication in distilled water. The extract was evaluated for DPPH radical scavenging activity, cytotoxicity, tyrosinase inhibition, melanin production, and associated signaling pathways in B16F10 murine melanoma cells. The rice bran extract exhibited DPPH radical scavenging activity and showed no cytotoxicity in B16F10 cells. It also inhibited tyrosinase activity in a dose-dependent manner and suppressed melanin synthesis in B16F10 cells. Mechanistically, the extract reduced the TRP1, TRP2, and MITF protein levels, while increasing the phosphorylation of Erk and Akt in B16F10 cells. In addition, treatment with PD98059 or LY294002 attenuated the extract-induced downregulation of MITF and altered MITF phosphorylation. These findings suggest that rice bran extract may serve as a potential cosmeceutical ingredient for controlling melanogenesis, warranting further cosmeceutical investigation.
Epigenetic alterations are increasingly being evaluated as diagnostic biomarkers and risk-stratification tools in surgical pathology and cytopathology. The clinical implementation of epigenetic biomarkers requires more than the demonstration of disease-associated molecular changes. DNA methylation, histone modifications, chromatin remodeling, and non-coding RNAs may provide clinically relevant information, but their clinical value depends on reproducibility, specimen adequacy, analytical robustness, interpretability, and suitability for clinical reporting. These requirements are particularly relevant in cytopathology and molecular testing of body fluid specimens, where specimens may have low cellularity or suboptimal nucleic acid quality, and morphological interpretation may be equivocal. Urothelial carcinoma represents an informative model because urine-based methylation assays illustrate both the potential and the limitations of epigenetic translation. These assays have been explored as adjunctive tools to cytology in selected diagnostic and surveillance settings, without replacing guideline-based cystoscopic follow-up. This editorial introduces the Special Issue "Epigenetics in Diagnostic Pathology: Translational Biomarkers, Technologies, and Clinical Impact" and supports a translational approach grounded in diagnostic pathology, in which epigenetic biomarkers are evaluated according to their capacity to generate reliable diagnostic evidence in routine clinical specimens.
