The pharmacological inhibition of Heat shock protein 90 (Hsp90) with KU711 or KU757 decreased the number of spheres and the percentage of ALDH-positive and CD44-positive cells and the level of BMI1 protein in parental and cisplatin-resistant HNSCC cell lines (Subramanian et al. 2017). The gene discussed is CD44; the disease is head and neck squamous cell carcinoma.