The present invention is directed to methods for treating cancer in a subject, such as a cancer of the endocrine system. In some aspects, the method includes administering to the subject one or more of a polo-like kinase 1 inhibitor, a mouse double minute 2 inhibitor, and/or a mitotic catastrophe inducing compound. In other aspects, the method includes measuring an expression level of one or more markers, including caspase 8 and caspase 9, to assess the functionality of the caspase cascade in the subject.