Bcl-6 (B-cell lymphoma 6) is a zinc finger transcriptional repressor belonging to the BTB-POZ family. It is predominantly expressed in B cells, regulating immune responses and B cell differentiation. Bcl-6 influences the cell cycle and apoptosis by repressing the transcriptional activity of specific target genes. It is localized in lymphoid tissues and involved in various signaling pathways, such as the NF-κB pathway. Specific expression and mutations of the Bcl-6 gene are closely associated with the development of lymphomas.