Since STAT5 activation in the various cancers is dependent on the phosphorylation by various tyrosine kinases, for example JAK2, Bcr-Abl, Flt3 and Src, targeting the tyrosine kinases to inhibit the activation of STAT5 is a feasible way of treating cancers dependent on STAT5 signalling. The gene discussed is STAT5A; the disease is cancer.