Prognostic impact of cytoplasmatic EGFR upregulation in patients with oral squamous cell carcinoma: A pilot study

Abstract

In various tumors, epidermal growth factor-receptor (EGFR) serves a role in tumorigenesis and has an impact on survival. Usually the EGF-receptor is located on the surface of the cell membrane and is involved in various signaling pathways. The dimerization of EGFR with other ErbB family proteins, such as HER2, is important for the tumor progression. Nevertheless, a second EGFR-associated signaling pathway appears to be important for tumor cells, which is cytoplasmic/nuclear EGFR. The present study examined the influence of membranous or cytoplasmic localized EGFR on the prognosis of patients with oral squamous cell carcinoma (OSCC). Slides from 45 OSCC tumor samples were stained against EGFR using immunohistochemistry and analysed by the Remmele score system. The association with histopathological parameters and survival data was analyzed. Cytoplasmatic EGFR localization was identified as an independent predictive biomarker for overall survival in the examined OSCC cohort according to multivariate Cox regression analysis. Positive cytoplasmatic EGFR staining was correlated with a higher risk of early death (RR=3.0; P=0.035), while membranous EGFR localization did not affect patient survival. To the best of our knowledge, the present study is the first study to demonstrate that cytoplasmatic-localized EGFR is an independent prognostic biomarker for the overall survival of patients with OSCC.

Postoperative Prognostic Predictors of Bile Duct Cancers: Clinical Analysis and Immunoassays of Tissue Microarrays

“…To our knowledge, this study is the first to evaluate the prognostic effect according to the location of EGFR in CCAs. 35 - 37…”

“…To our knowledge, this study is the first to evaluate the prognostic effect according to the location of EGFR in CCAs. [35][36][37] Downregulation of EGFR by endocytosis and lysosomal degradation has been regarded a key mechanism of signal attenuation. 38 Therefore, impaired downregulation of signaling receptors is strongly associated with carcinogenesis by leading to increased and uncontrolled receptor signaling.…”