Molecular signature refers to specific patterns or characteristics found at the molecular level that can be used to identify or classify different biological processes or diseases. These signatures can be derived from various molecular data sources, such as gene expression, methylation patterns, protein levels, and metabolites. By analyzing these molecular signatures, researchers can gain insights into the underlying mechanisms of diseases, identify potential biomarkers for diagnosis or prognosis, and develop targeted therapies. Molecular signature analysis is commonly used in fields such as genomics, oncology, personalized medicine, and drug development.