As such, in order to confirm that the phenotype observed in HNSCC cell lines treated with LRRK2-IN-1 indeed resulted from a direct inhibition of DCLK1 activity, we utilized a DCLK1 specific small interfering RNA (siRNA) to reduce its expression in selected HNSCC cell lines (JHU-011, JHU-022, JHU-029 and SCC22b) with high endogenous DCLK1 expression. The gene discussed is LRRK2; the disease is head and neck squamous cell carcinoma.