Abstract 4735: Expression of Notch1 and Numb in small cell lung cancer

Abstract

Abstract Background: Notch signaling plays an important role in tumorigenesis. Numb represses intracellular Notch signaling. Previous studies have demonstrated that Notch signaling suppresses the proliferation of small cell lung cancer (SCLC) cell lines. However, in SCLC, the association between Notch1 and Numb expression and clinicopathological factors or prognosis has remained unclear. In this study, we evaluated the expression of Notch1 and Numb in SCLC. Methods: We immunohistochemically assessed 125 SCLCs that were surgically resected at 16 institutions participating in either the Hokkaido Lung Cancer Clinical Study Group Trial (HOT) or the Fukushima Investigative Group for Healing Thoracic Malignancy (FIGHT) between 2003 and 2013. Correlations between Notch1 or Numb expression and various clinicopathological features were evaluated. Results: Notch1 expression was associated with ECOG performance status. Numb expression was associated with age, sex, and pathological histology (SCLC or Combined SCLC). Analysis of cellular biological expression did not demonstrate a significant correlation between the expression of Notch1 and of Numb. Multivariate Cox regression analysis showed that high Notch1 expression was an independent favorable prognostic factor for SCLC (hazard ratio = 0.503, P = 0.023). Conclusions: We demonstrate that Notch1 expression, but not Numb, is associated with prognosis in SCLC and may provide a novel prognostic marker of SCLC. Citation Format: Hajime Kikuchi, Jun Sakakibara-Konishi, Megumi Furuta, Hiroshi Yokouchi, Hiroshi Nishihara, Shigeo Yamazaki, Uramoto Hidetaka, Fumihiro Tanala, Masao Harada, Kenji Akie, Fumiko Sugaya, Yuka Fujita, Kei Takamura, Tetsuya Kojima, Toshiyuki Harada, Mitsunori Higuchi, Osamu Honjo, Yoshinori Minami, Naomi Watanabe, Satoshi Oizumi, Hiroyuki Suzuki, Takashi Ishida, Hiotoshi Dosaka-Akita, Hiroshi Isobe, Mitsuru Munakata, Masaharu Nishimura. Expression of Notch1 and Numb in small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4735. doi:10.1158/1538-7445.AM2017-4735