The present invention provides methods and compositions for treatment, screening, diagnosis and prognosis of cancer, such as lymphoma, myeloma, leukaemia, thyroid cancer, bladder cancer, breast cancer, gastric cancer, esophagus cancer, head and neck cancer and skin cancer, for monitoring the effectiveness of cancer, such as lymphoma, myeloma, leukaemia, thyroid cancer, bladder cancer, breast cancer, gastric cancer, esophagus cancer, head and neck cancer and skin cancer treatment, and for drug development.LA INVENCIÓN PROPORCIONA A LY75 COMO TERAPÉUTICO DEL CÁNCER Y OBJETIVO DE DIAGNÓSTICO