Hsp90 is part of the class of molecular chaperone proteins that plays a central role in the assembly of multi-protein chaperone complexes and regulates folding, stability and function of many client proteins that are oncogenic drivers of lung adenocarcinoma subsets such as mutant EGFR, wild-type CRAF, mutant BRAF, wild-type and mutant HER2, and EML4-ALK fusion protein positive NSCLC. The gene discussed is ALK; the disease is lung adenocarcinoma.