Abstract B17: Interleukin-17 and -22 expression in non-small cell lung cancer

Background: In non-small cell lung cancer (NSCLC) the TNM staging remains standard for prognostic assessment and therapy decisions. Nevertheless, stage-specific outcomes vary significantly, indicating a need for additional prognosticators. In this retrospective study we wanted to assess the role of the mediator interleukin-22 (IL-22), as IL-22 is known to be involved in various lung diseases and to be elevated in lung cancer patients. Moreover, we evaluated interleukin-17 (IL-17), which also depicts a proinflammatory cytokine, but seems to play a dual role in antitumor immunity. We asked the question of their link to prognosis, therapy response and recurrence. Methods: Tissue microarrays (TMAs) were generated from formalin-fixed, paraffin embedded tissue of 138 curatively resected patients with stage IA-IV NSCLC. TMAs included each three cores from the tumor center (CT) and invasive margin (IM), selected from areas with the most dense lymphocytic infiltrates. IL-22 and IL-17 expression of the tissue was analyzed by immunohistochemistry via cytoplasmic staining (double-staining: IL-22, CD3 resp. IL-17, CD3). Results: IL-22 expression status in adeno and SCC does not seem to have a prognostic impact on survival, regardless of the localization. However, a high IL-22 CT/IM ratio in adenocarcinoma is clearly linked to longer overall survival; this cannot be seen in SCC. For IL-17 a distinct tendency is visible for adeno and SCC in the invasive margin as well as in the tumor center—interestingly, this is more clear for SCC. In SCC a high CT/IM ratio for IL-17 seems to have a positive prognostic impact on overall survival. Patient numbers will be enlarged to validate these findings. Conclusion: The cytokines IL-22 and IL-17 seem—depending on histology and location—to have a prognostic impact on overall survival in NSCLC. In previous experiments we showed that multispectral assessment of CD8 and PD-L1 has a clear correlation with clinical outcome. Adding cytokines to this method might open novel avenues for predicting clinical outcome and therapeutic efficacy in NSCLC. Citation Format: Julia Stump, Yue Jiang, Clara Karches, Javier Suarez Gosalvez, Jens Neumann, Sebastian Kobold, Rudolf Hatz, Hauke Winter, Amanda Tufman, Rudolf M. Huber, Simone Reu. Interleukin-17 and -22 expression in non-small cell lung cancer [abstract]. In: Proceedings of the Fifth AACR-IASLC International Joint Conference: Lung Cancer Translational Science from the Bench to the Clinic; Jan 8-11, 2018; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(17_Suppl):Abstract nr B17.