MAGEA4 and bladder transitional cell carcinoma: Among these, chromosome X-encoded CT antigens antigens are highly expressed in BLCA.28,29 An early study identified increased expression of MAGEA1 (21% of cases) and MAGEA3 (35% of cases) in primary transitional cell carcinoma of the bladder.30 Further research linked elevated expression of several MAGE genes with advanced disease stages, with MAGEA9 and MAGEA4 being particularly associated with metastasis and recurrence.