Cancer cell lines, including 2D, 3D, and co-cultures, are vital for cancer research, drug discovery, and personalized medicine. Recent advancements like microfluidic systems and primary tumor cultures enhance their in vivo relevance. Exosomes, nano-vesicles from cells, show promise in promoting hair growth and regeneration by improving the scalp environment. Validation and 3D models further improve research accuracy and pave the way for transformative healthcare solutions.