TP53 and ovarian cancer: In contrast, in ovarian cancer, where p53 is the most common genetic alteration, a number of in vitro studies have shown an apoptotic effect of vitamin D. Notably, in ovarian cancer cell lines, vitamin D has been shown to have an apoptotic effect that is p53-independent via the activation of caspase 9 and the downregulation of telomerase, either via decreasing its stability or via suppressed expression induced by miR-498 [9].