Micropeptides: The Dawn of New Molecular Targets and Therapeutic Agents

Small open reading frames (sORFs) encode micropeptides, which are a promising yet largely untapped resource for creating peptide design templates. Owing to their concise nature and functional efficiency, micropeptides often rely on essential structural elements and brief linear motifs, such as domains for membrane interaction, targeting sequences, and sites for protein–protein interactions, to fulfill their biological functions. This inherent simplicity makes them particularly suitable for a bottom-up design approach aimed at identifying, extracting, and systematically refining functional motifs to develop novel bioactive peptides. This review addresses the critical question of how micropeptides, particularly those involved in tumor regulation, can be explored as emerging therapeutic targets, functional templates for peptide design, and potential future therapeutic agents, by synthesizing current understanding of their mechanisms, functional significance in cancer, and the computational and design strategies for their clinical translation. We examined the current methods for analyzing the sequence and structural characteristics that underpin their functional activity and investigated how these attributes can be leveraged for drug discovery and design. Finally, we underscore the primary challenges and future prospects in converting sORF-encoded micropeptides into clinically relevant molecules with the aim of broadening the current scope of the druggable proteome.