Mitotic apparatus proteins

Mitotic apparatus proteins constitute a complex network of structural, motor, and regulatory proteins essential for the assembly and function of the mitotic spindle during cell division (NIH, PubMed). This group includes microtubules (composed of tubulin), motor proteins such as kinesins (e.g., KIF11/Eg5) and dyneins, and regulatory enzymes like Aurora kinases and Polo-like kinases (PLK1) (UniProt, NIH). These proteins ensure the accurate segregation of chromosomes into daughter cells, a process that is tightly regulated by the spindle assembly checkpoint (PubMed). In many cancers, these proteins are overexpressed or dysregulated to support rapid and uncontrolled cell proliferation, making them significant therapeutic targets (Frontiers in Oncology). Drugs targeting this apparatus, such as taxanes (e.g., paclitaxel) and vinca alkaloids (e.g., vincristine), have long been staples of chemotherapy by disrupting microtubule dynamics (PubChem). Newer therapeutic strategies involve small molecule inhibitors of specific mitotic kinases and kinesins, such as alisertib and volasertib, which aim to achieve more selective mitotic arrest and reduce off-target toxicities like peripheral neuropathy (ClinicalTrials.gov). Despite their efficacy, resistance mechanisms such as tubulin mutations and the upregulation of efflux pumps remain significant clinical challenges (PubMed).

Other names

Mitotic spindle proteinsSpindle apparatus proteinsMitotic network proteinsNuclear mitotic apparatus protein 1 (NuMA1)

Drugs targeting mitotic apparatus proteins primarily act by disrupting the assembly, stability, or dynamics of the mitotic spindle (PubMed). This includes stabilizing microtubules (taxanes) or destabilizing them (vinca alkaloids), inhibiting the activity of essential mitotic kinases such as Aurora A/B and PLK1, or blocking the function of mitotic motor proteins like KIF11/Eg5 (PubChem, NIH). These actions lead to prolonged mitotic arrest at the spindle assembly checkpoint, ultimately triggering programmed cell death (apoptosis) in rapidly dividing cells.