PLK4 and thyroid gland undifferentiated (anaplastic) carcinoma: Zhu et al. have demonstrated an overexpression of PLK4 in anaplastic thyroid cancer cell lines and inhibition of PLK4 resulted in decreased cell viability, induction of apoptosis, G2/M phase cell-cycle arrest, and deactivated Wnt/β-catenin pathway in C643 and 8305C cells.128