Abstract 2509: Abundant glucocorticoid receptor (GR) expression in human tumors: A tissue microarray study on more more than 18,000 tumors

Abstract The glucocorticoid receptor (GR, or GCR) is a nuclear receptor protein for cortisol and other glucocorticoids and regulates the transcription of thousands of genes involved in metabolism, development, stress, and inflammatory response. In cancer, both an oncogenic and a tumor suppressive function of GR has been proposed. To comprehensively evaluate GR expression in normal and tumorous tissues, a tissue microarray containing 18,570 samples from 147 different tumor types and subtypes and 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry (IHC). GR positivity was found in 76.3% of 14,349 interpretable cancers, including 18.5% with weak, 19.6% with moderate, and 38.3% with strong positivity. GR positivity of at least a fraction of tumors was found in all 147 analyzed tumor types and at least one strongly GR positive tumor was found in 136 tumor types. 77 of our 147 tumor entities showed GR positivity of variable intensity in all analyzed cases. 43 further tumor entities showed GR positivity in 80-99.9% of cases. 21 tumor entities had a GR positivity rate between 50 and 80%, including urothelial carcinoma as well as gastric and esophageal adenocarcinoma. Only 6 tumor types had less than 50% GR positive. These included adenomas (21.7-32.5%), adenocarcinomas (17%) and neuroendocrine carcinomas (45.5%) of the colorectum. Reduced GR staining was significantly associated with adverse histopathological and clinical features in several tumor types. Low GR expression was linked to grade progression in pTa (p<0.0001) and to nodal metastasis in pT2-4 urothelial carcinoma of the urinary bladder (p=0.0051), advanced pT stage (p=0.0006) and estrogen receptor positivity (p=0.0126) in breast carcinomas of no special type (NST), as well as to high grade (p≤0.0076), advanced pT stage (p<0.0001), distant metastasis (p=0.0081), and poor overall survival (p=0.002) in clear cell renal cell carcinoma. GR expression was unrelated to clinic-pathological parameters in gastric, pancreatic, and colorectal adenocarcinoma as well as in serous high-grade carcinoma of the ovary. In summary, our data demonstrate frequent GR expression across all cancer types. Significant associations between reduced GR expression and unfavorable tumor features in some but not all tumor types suggest that the functional importance of GR regulated genes for cancer progression depends on the cell of tumor origin. Citation Format: Christina Tsourlakis, Frederike Wegener, Katharina Möller, Martina Kluth, Claudia Hube-Magg, Christian Bernreuther, Guido Sauter, Andreas H. Marx, Ronald Simon, Till Krech, Christoph Fraune, Natalia Gorbokon, Maximilian Lennartz, Sarah Minner, Florian Viehweger. Abundant glucocorticoid receptor (GR) expression in human tumors: A tissue microarray study on more more than 18,000 tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2509.