C-Jun is a protein that plays a crucial role in regulating gene expression. It is part of the AP-1 transcription factor complex, which is involved in various cellular processes, including cell growth, differentiation, and apoptosis (programmed cell death). C-Jun is activated in response to various stimuli, such as stress and growth factors, allowing it to influence the activity of specific genes. In addition to its role in normal cellular functions, C-Jun is also implicated in several diseases, including cancer. Abnormal regulation of C-Jun can lead to uncontrolled cell proliferation and survival, contributing to tumor development. Understanding C-Jun's functions can help researchers develop targeted therapies for related conditions.