STAT5A and head and neck squamous cell carcinoma: Especially for SCC, blockade of STAT5B in a xenograft model in head and neck squamous cell carcinoma (HNSCC) resulted in tumor growth inhibition [20], and the constitutive activation of STAT5A was one of the early events in tobacco mediated-oral squamous cell carcinoma (OSCC) in the eastern Indian population [21].