Because of its integral role in microtubule assembly and therefore mitosis, TPX2 is found to be overexpressed in different types of human cancers including hepatocellular carcinoma [25], medullary thyroid cancer [26], bladder carcinoma [27, 28], prostate cancer [29] and estrogen receptor-positive metastatic breast cancer [30], contributing to tumor growth and metastasis. This evidence concerns the gene ESR1 and cancer.