Glucocorticoid Receptor Expression in 20 Solid Tumor Types Using Immunohistochemistry Assay

Cancer Manag Res. 2017 Mar 6;9:65-72. doi: 10.2147/CMAR.S124475. eCollection 2017.

Abstract

Background: Glucocorticoid receptor (GR) activity plays a role in many aspects of human physiology and may play a crucial role in chemotherapy resistance in a wide variety of solid tumors. A novel immunohistochemistry (IHC) based assay has been previously developed and validated in order to assess GR immunoreactivity in triple-negative breast cancer. The current study investigates the standardized use of this validated assay to assess GR expression in a broad range of solid tumor malignancies.

Methods: Archived formalin-fixed paraffin-embedded tumor bank samples (n=236) from 20 different solid tumor types were analyzed immunohistochemically. Nuclear staining was reported based on the H-score method using differential intensity scores (0, 1+, 2+, or 3+) with the percent stained (out of at least 100 carcinoma cells) recorded at each intensity.

Results: GR was expressed in all tumor types that had been evaluated. Renal cell carcinoma, sarcoma, cervical cancer, and melanoma were those with the highest mean H-scores, indicating high levels of GR expression. Colon, endometrial, and gastric cancers had lower GR staining percentages and intensities, resulting in the lowest mean H-scores.

Conclusion: A validated IHC assay revealed GR immunoreactivity in all solid tumor types studied and allowed for standardized comparison of reactivity among the different malignancies.

Impact: Baseline expression levels of GR may be a useful biomarker when pharmaceutically targeting GR in research or clinical setting.

Keywords: glucocorticoid receptor expression; immunohistochemistry; solid tumors.