Also, p53 silencing significantly reduced the antiproliferative effects of 5-fluorouracil and methotrexate or doxorubicin, in human cancer cell lines harboring wild type (wt) p53 [78] and treatment of human leukemia and lymphoma cell lines with CX-5461, a selective inhibitor of Pol I transcription [7], was much more effective in cells with wt p53 in comparison with those with mutated p53 [75, 79]. Here, TP53 is linked to leukemia.