TP53 and colorectal cancer: It has previously been reported that treatment of a colorectal cancer cell line with low doses of doxorubicin induces senescence rather than apoptosis,27 but it has also been suggested that in cells that are unable to induce apoptosis, senescence may act as a ‘backup’ response, strongly contributing to the treatment outcome.28 Furthermore, our results are supported by several in vivo studies, indicating that upon chemotherapy treatment, the role of p53 as a tumor suppressor may be mediated through induction of senescence rather than apoptosis.29,30