Induction of \u3cem\u3eIL19\u3c/em\u3e Expression through JNK and cGAS-STING Modulates DNA Damage–Induced Cytokine Production

Cytokine production is a critical component of cell-extrinsic responses to DNA damage and cellular senescence. Here, we demonstrated that expression of the gene encoding interleukin-19 (IL-19) was enhanced by DNA damage through pathways mediated by c-Jun amino-terminal kinase (JNK) and cGAS-STING and that IL19 expression was required for the subsequent production of the cytokines IL-1, IL-6, and IL-8. IL19 expression was stimulated by diverse cellular stresses, including inhibition of the DNA replication checkpoint kinase ATR (ataxia telangiectasia and Rad3-related protein), oncogene expression, replicative exhaustion, oxidative stress, and DNA double-strand breaks. Unlike the production of IL-6 and IL-8, IL19 expression was not affected by abrogation of signaling by the IL-1 receptor (IL-1R) or the mitogen-activated protein kinase p38. Instead, the DNA damage–induced production of IL-1, IL-6, and IL-8 was substantially reduced by suppression of IL19 expression. The signaling pathways required to stimulate IL19 expression selectively depended on the type of DNA-damaging agent. Reactive oxygen species and the ASK1-JNK pathway were critical for responses to ionizing radiation (IR), whereas the cGAS-STING pathway stimulated IL19 expression in response to either IR or ATR inhibition. Whereas induction of IL1, IL6, and IL8 by IR depended on IL19 expression, the cGAS-STING–dependent induction of the immune checkpoint gene PDL1 after IR and ATR inhibition was independent of IL19. Together, these results suggest that IL-19 production by diverse pathways forms a distinct cytokine regulatory arm of the response to DNA damage

Characterization and use of the interaction between ATR suppression and p53 deficiency

p53 influences a staggering array of cellular processes that ultimately impact diverse aspects of normal physiology. Importantly, the majority of human cancers are functionally deficient in p53, and loss of this critical tumor suppressor is often associated with resistance to conventional chemotherapy. Efforts to identify novel therapeutic approaches to p53-deficienct malignancies have suggested that the ATR-CHK1 pathway may be a useful target, as suppression of ATR or CHK1 is especially toxic to model organisms lacking p53. Unfortunately, the precise nature of this interaction has remained poorly understood and its potential for use in a therapeutic setting is currently unclear. This thesis presents a detailed characterization of a synthetic lethal interaction between complete ATR loss and p53 deficiency in non-malignant tissues and provides evidence that this deleterious outcome is partly the product of a non-cell autonomous interaction. These findings are then applied to the clinically relevant problem of p53-deficient malignancies in the development and use of a novel genetic system to conditionally suppress, rather than eliminate, ATR in adult tissues and model p53-deficient cancers

Characterization and use of the interaction between ATR suppression and p53 deficiency

p53 influences a staggering array of cellular processes that ultimately impact diverse aspects of normal physiology. Importantly, the majority of human cancers are functionally deficient in p53, and loss of this critical tumor suppressor is often associated with resistance to conventional chemotherapy. Efforts to identify novel therapeutic approaches to p53-deficienct malignancies have suggested that the ATR-CHK1 pathway may be a useful target, as suppression of ATR or CHK1 is especially toxic to model organisms lacking p53. Unfortunately, the precise nature of this interaction has remained poorly understood and its potential for use in a therapeutic setting is currently unclear. This thesis presents a detailed characterization of a synthetic lethal interaction between complete ATR loss and p53 deficiency in non-malignant tissues and provides evidence that this deleterious outcome is partly the product of a non-cell autonomous interaction. These findings are then applied to the clinically relevant problem of p53-deficient malignancies in the development and use of a novel genetic system to conditionally suppress, rather than eliminate, ATR in adult tissues and model p53-deficient cancers

Oncogenic stress sensitizes murine cancers to hypomorphic suppression of ATR

Oncogenic Ras and p53 loss-of-function mutations are common in many advanced sporadic malignancies and together predict a limited responsiveness to conventional chemotherapy. Notably, studies in cultured cells have indicated that each of these genetic alterations creates a selective sensitivity to ataxia telangiectasia and Rad3-related (ATR) pathway inhibition. Here, we describe a genetic system to conditionally reduce ATR expression to 10% of normal levels in adult mice to compare the impact of this suppression on normal tissues and cancers in vivo. Hypomorphic suppression of ATR minimally affected normal bone marrow and intestinal homeostasis, indicating that this level of ATR expression was sufficient for highly proliferative adult tissues. In contrast, hypomorphic ATR reduction potently inhibited the growth of both p53-deficient fibrosarcomas expressing H-rasG12V and acute myeloid leukemias (AMLs) driven by MLL-ENL and N-rasG12D. Notably, DNA damage increased in a greater-than-additive fashion upon combining ATR suppression with oncogenic stress (H-rasG12V, K-rasG12D, or c-Myc overexpression), indicating that this cooperative genome-destabilizing interaction may contribute to tumor selectivity in vivo. This toxic interaction between ATR suppression and oncogenic stress occurred without regard to p53 status. These studies define a level of ATR pathway inhibition in which the growth of malignancies harboring oncogenic mutations can be suppressed with minimal impact on normal tissue homeostasis, highlighting ATR inhibition as a promising therapeutic strategy

Predictors of Mortality in HPV-Associated Oropharynx Carcinoma Treated With Surgery Alone.

© 2019 The American Laryngological, Rhinological and Otological Society, Inc. Objective: Survival outcomes for human papillomavirus-associated oropharynx squamous cell carcinoma (HPV + OPSCC) treated with surgery alone are unclear. To increase understanding, we assessed overall survival (OS) outcomes using the national cancer database (NCDB). Methods: We conducted a retrospective analysis of OS of 736 NCDB HPV + OPSCC patients who underwent surgery alone from 2010 to 2014 using univariate and multivariate analyses and the Kaplan-Meir method. Results: Multivariable analysis found the following independent risk factors for death: American Joint Commission on Cancer (AJCC) 8th edition pathologic stage(p)N2 versus pN0 disease (hazard ratio [HR], 5.5; P = 0.000006), macroscopic extranodal extension (ENE) versus non-ENE (HR, 4.9; P \u3c 0.02), a positive lymph nodes (LN) percentage of ≥10% (HR, 4.2; P = 0.0002), and five or more positive LNs (HR, 4.9; P = 0.00004). Three-year OS was significantly worse for AJCC 8th edition pN2 versus pN0 but not for 7th edition pN2 versus pN0 disease. Five-year OS was significantly worse for positive versus negative surgical margins, AJCC 8th edition stage II versus I, and either microscopic or macroscopic ENE versus non-ENE positive LNs. For 523 (71%) AJCC 8th edition stage I patients and for 283 (38%) patients who were pT1–T2, with negative margins, pN0–N1, with ≤4 pathologic LNs, without ENE, and with \u3e20 LNs removed during neck dissection, the 3-year OS rates were 93% and 95%, respectively, and the 5-year OS rates were 91% and 95%, respectively. Conclusion: In the context of the lack of detail and possible inaccuracies found in the NCDB, surgery alone for AJCC 8th edition stage I HPV + OPSCC, particularly pT1–T2, pN0–N1 with ≤4 pathologic LNs, without ENE, and with negative surgical margins has a high OS. Level of Evidence: 4 Laryngoscope, 130:E423–E435, 2020

Predictors of Mortality in HPV-Associated Oropharynx Carcinoma Treated With Surgery Alone

© 2019 The American Laryngological, Rhinological and Otological Society, Inc. Objective: Survival outcomes for human papillomavirus-associated oropharynx squamous cell carcinoma (HPV + OPSCC) treated with surgery alone are unclear. To increase understanding, we assessed overall survival (OS) outcomes using the national cancer database (NCDB). Methods: We conducted a retrospective analysis of OS of 736 NCDB HPV + OPSCC patients who underwent surgery alone from 2010 to 2014 using univariate and multivariate analyses and the Kaplan-Meir method. Results: Multivariable analysis found the following independent risk factors for death: American Joint Commission on Cancer (AJCC) 8th edition pathologic stage(p)N2 versus pN0 disease (hazard ratio [HR], 5.5; P = 0.000006), macroscopic extranodal extension (ENE) versus non-ENE (HR, 4.9; P \u3c 0.02), a positive lymph nodes (LN) percentage of ≥10% (HR, 4.2; P = 0.0002), and five or more positive LNs (HR, 4.9; P = 0.00004). Three-year OS was significantly worse for AJCC 8th edition pN2 versus pN0 but not for 7th edition pN2 versus pN0 disease. Five-year OS was significantly worse for positive versus negative surgical margins, AJCC 8th edition stage II versus I, and either microscopic or macroscopic ENE versus non-ENE positive LNs. For 523 (71%) AJCC 8th edition stage I patients and for 283 (38%) patients who were pT1–T2, with negative margins, pN0–N1, with ≤4 pathologic LNs, without ENE, and with \u3e20 LNs removed during neck dissection, the 3-year OS rates were 93% and 95%, respectively, and the 5-year OS rates were 91% and 95%, respectively. Conclusion: In the context of the lack of detail and possible inaccuracies found in the NCDB, surgery alone for AJCC 8th edition stage I HPV + OPSCC, particularly pT1–T2, pN0–N1 with ≤4 pathologic LNs, without ENE, and with negative surgical margins has a high OS. Level of Evidence: 4 Laryngoscope, 130:E423–E435, 2020