RB1 and ovarian cancer: Whereas in cervical cancer strong p16INK4a overexpression can be observed in virtually all high-grade dysplastic and cancerous cases as a consequence of functional inactivation of pRb by the E7 protein of high-risk HPV, high p16INK4a protein levels characterise only a subgroup of patients with advanced-stage ovarian cancers associated with a worse prognosis.