Overexpression of Sigma1 Receptor and Its Positive Associations With Pathologic TNM Classification in Esophageal Squamous Cell Carcinoma

Abstract

SummarySigma1 receptor (sigma1R), a significant protein, has been found to be frequently upregulated in human tumor cells and tissues. It has been demonstrated that sigma1R is involved in proliferation and adhesion of cancer cells. However, the significance of sigma1R expression in esophageal squamous cell carcinoma (ESCC) remains unclear. In this article, by a series of methods, the authors examined the expression of sigma1R protein in ESCC cell lines and tissues. Flow cytometry indicated intense staining of sigma1R in ESCC cells. Immunocytochemistry staining demonstrated that sigma1R was mainly distributed in cytoplasm and nucleus in ESCC cell lines. Western blotting was performed to characterize the relative expression of sigma1R in different ESCC cell lines. Moreover, different levels of sigma1R were presented from normal epithelium to carcinoma by immunohistochemistry analysis, which demonstrated that sigma1R was highly expressed in tumors. Association analysis showed significant correlations between total sigma1R protein levels and pathologic TNM (pTNM) classification of tumors (r=0.216, p=0.011). Furthermore, the sigma1R in the nucleus was significantly correlated with pTNM classification and lymph node metastasis (r=0. 263, p=0.002, and r=0.269, p=0.002, respectively). These data indicated that sigma1R may serve as a potential predictive factor for pTNM classification and tumor development in ESCC. (J Histochem Cytochem 60:457-466, 2012)

Sigma-1 receptor (σ1R) is downregulated in hepatic malignant tumors and regulates HepG2 cell proliferation, migration and apoptosis

“…A novel finding in the present study was that σ1R was expressed at low levels in HCC, and that there was a statistically significant difference between its expression levels in benign hepatic tissue and HCC (P<0.01). The decreased expression of σ1R in HCC was an interesting phenomenon, which was inconsistent with former studies in other tumor types (16,18,25). We considered that this contradiction may indicate a different molecular biological function in HCC compared with other tumor types.…”

“…Additionally, the upregulation of σ1R was reported to correlate with the biological behavior of tumors, such as proliferation, adhesion and cell death (14,16). Our previous study showed that σ1R was overexpressed in human esophageal squamous cell carcinoma and that the overexpression of σ1R was significantly associated with the pathological TNM classification and lymph node metastasis (18). However, the expression of σ1R and its biological relevance in HCC have not yet been identified.…”

Combined detection of serum autoantibodies as diagnostic biomarkers in esophagogastric junction adenocarcinoma

“…Immunohistochemistry was performed using 2-step protocol according to the manufacturer’s instructions (PV-9000 Polymer Detection System, ZSGB-BIO, Beijing, China) as described previously [ 15 ]. Rabbit polyclonal antibodies against p53, NY-ESO-1, MMP-7, Hsp70, PRDX6, and Bmi-1 (all 1:200; Immunosoft, Zhoushan, China) were incubated overnight at 4 °C.…”

A three-protein signature and clinical outcome in esophageal squamous cell carcinoma

“…TMA construction has been described in our previous studies [37-40]. Two tissue cores of 1.8 mm in diameter were taken from the donor blocks and transferred to the recipient paraffin block at defined array positions.…”

“…Immunohistochemistry was carried out by a two-step protocol (PV-9000 Polymer Detection System, ZSGB-BIO, Beijing, China) as previously described [40]. …”