Activated Cdk1 complexes translocate into the nucleus during prophase where phosphorylate numerous substrates in order to enhance their activation as the cells progresses trough prophase, prometaphase, and metaphase.Recently we identified a new player: FEZ1/LZTS1 that contributes to the fine-tuning of the molecular events that determine progression through mitosis, and here will review its role in cancer development and in M phase regulation..     ///    Fez1/Lzts1 a new mitotic regulator implicated in cancer development.. 