Acute DNA damage activates the tumour suppressor p53 to promote radiation-induced lymphoma

作者：Lee Chang Lung; Castle Katherine D; Moding Everett J; Blum Jordan M; Williams Nerissa; Luo Lixia; Ma Yan; Borst Luke B; Kim Yongbaek; Kirsch David G^*

来源：Nature Communications, 2015, 6(1): 8477.

DOI：10.1038/ncomms9477

Genotoxic cancer therapies, such as chemoradiation, cause haematological toxicity primarily by activating the tumour suppressor p53. While inhibiting p53-mediated cell death during cancer therapy ameliorates haematologic toxicity, whether it also impacts carcinogenesis remains unclear. Here we utilize a mouse model of inducible p53 short hairpin RNA (shRNA) to show that temporarily blocking p53 during total-body irradiation (TBI) not only ameliorates acute toxicity, but also improves long-term survival by preventing lymphoma development. Using KrasLA1 mice, we show that TBI promotes the expansion of a rare population of thymocytes that express oncogenic Kras(G12D). However, blocking p53 during TBI significantly suppresses the expansion of Kras(G12D)- expressing thymocytes. Mechanistically, bone marrow transplant experiments demonstrate that TBI activates p53 to decrease the ability of bone marrow cells to suppress lymphoma development through a non-cell-autonomous mechanism. Together, our results demonstrate that the p53 response to acute DNA damage promotes the development of radiation-induced lymphoma.

• 出版日期2015-9