Irradiation Induces Gasdermin E-Triggered Tumor Immunity to Inhibit Esophageal Carcinoma Cell Survival.

Gasdermin E (GSDME), an executor of pyroptosis, can be activated by caspase-3 and has been recognized as a tumor suppressor in various human cancers. In addition, caspase-3/GSDME signal-induced pyroptosis is a form of immunogenic cell death (ICD). In this study, we aimed to understand the association between radiotherapy and caspase-3/GSDME signal-related ICD in esophageal carcinoma (EC) cells. The expression of caspase-3 and GSDME in two EC cell lines, ECA-109 and KYSE-150, was silenced or overexpressed by transfection with specific siRNAs or overexpression vectors. Cells were subjected to 0-8 Gy irradiation, and cell death was evaluated by CCK-8 assay, annexin V-FITC staining, lactate dehydrogenase (LDH) detection kit, Western blotting, and immunofluorescence. Irradiation in both EC cell lines promoted dose-dependent viability loss and apoptosis. More specifically, 8 Gy X-ray increased the apoptosis rate from 4.1 to 12.8% in ECA-109 cells and from 4.6 to 21.1% in KYSE-150 cells. In irradiated EC cells, the levels of LDH release and caspase-3/GSDME cleavage were increased. Caspase-3 silencing inhibited irradiation-induced GSDME cleavage and EC cell death. Furthermore, we identified the death of EC cells suppressed by caspase-3 siRNA, and the levels of CRT, HMGB1, HSP70, and HSP90 were also markedly downregulated by caspase-3 siRNA. Similarly, GSDME silencing diminished irradiation-induced EC cell death and the levels of ICD markers. Overexpression of caspase-3 and GSDME accelerated irradiation-induced ICD. In summary, irradiation in EC cells induces GSDME-mediated pyroptosis and activates ICD to inhibit esophageal carcinoma cell survival.

The effects of air pollution on mortality and clinicopathological features of esophageal cancer.

This study aimed to estimate the associations between air pollution and esophageal cancer. In the ecologic cross-sectional study, correlation analyses were made between city-level mean concentrations of particulate matter less than 10µm in aerodynamic diameter (PM10), SO2, NO2 and city-level age-standardized mortality rates of esophageal cancer in Shandong Province, China. PM10 (p=0.046) and NO2 (p=0.03) both had significant linear correlations with esophageal cancer mortality rates. After introducing smoking as a risk factor in models of multiple linear regression analyses, PM10 was still an independent risk factor that increased esophageal cancer mortality rates. This study further compared clinicopathological features of 1,255 eligible esophageal squamous cell carcinoma patients by dividing them into different pollution level groups. There was statistically significant difference in gender distributions (p=0.02) between groups after subgroup analysis. Female patients accounted for a higher proportion in the high PM10 level group than in the low PM10 level group. It suggested that females were more sensitive to higher PM10 level pollution. The features that manifested the degree of malignancy of esophageal cancer, including primary tumor invasion, regional lymph nodes metastasis, histological grade, stage, lymph-vascular invasion and tumor size demonstrated no statistically significant difference between groups.

Down-regulation of stromal caveolin-1 expression in esophageal squamous cell carcinoma: a potent predictor of lymph node metastases, early tumor recurrence, and poor prognosis.

BACKGROUND: Recent studies have identified loss of stromal caveolin-1 (Cav-1) expression as a new prognostic histological characteristic in various types of human cancers. However, the clinical and pathological significance of stromal Cav-1 expression in esophageal squamous cell carcinoma (ESCC) remains largely unknown. We examined Cav-1 expression in both tumor and stromal cells in ESCC tissue by immunohistochemical analysis to evaluate its clinicopathological significance and prognostic value. METHODS: A total of 110 patients with ESCC who underwent surgical resection were included in this study. The expression of Cav-1 in both tumor and stromal cells in esophageal tumor tissues was examined immunohistochemically. RESULTS: Cav-1 expression was found in the cytoplasm of both tumor and stromal cells. Tumor Cav-1 overexpression was observed in 37.3 % tumors, which correlated to deeper tumor invasion (p = 0.038). Down-regulation of stromal Cav-1 expression was observed in 40.9 % tumors. The stromal Cav-1 down-regulation group had more lymph node metastases and more locoregional recurrences than those with higher expression (p = 0.020 and p = 0.002, respectively). In addition, down-regulation of stromal Cav-1 expression was associated with shorter disease-free survival (p < 0.001) and overall survival (p < 0.001). Multivariate analysis revealed that down-regulation of stromal Cav-1 expression was an independent prognostic factor for both disease-free survival (p = 0.028) and overall survival (p = 0.007). CONCLUSIONS: Down-regulation of stromal Cav-1 expression in ESCC had high malignant potential. It predicts high-risk of lymph node metastases and locoregional recurrence, and it could be a powerful prognostic marker for patients with ESCC.

Detection of D2-40 monoclonal antibody-labeled lymphatic vessel invasion in esophageal squamous cell carcinoma and its clinicopathologic significance.

OBJECTIVE: This study aims to investigate the clinicopathologic significance of lymphatic vessel invasion (LVI) labeled by D2-40 monoclonal antibody in esophageal squamous cell carcinoma (ESCC). METHODS: Immunohistochemical assay was used to detect the expression of D2-40 and LVI in 107 ESCC patients. Then, the correlation between the clinicopathologic feature and the overall survival time of the patients was analyzed. RESULTS: The lymph node metastasis rates were 70% and 21% in the LVI-positive and LVI-negative groups, respectively. The nodal metastasis rate was higher in the LVI-positive group than in the LVI-negative group. Multivariate regression analysis showed that LVI was related to nodal metastasis (P<0.001). The median survival time of the patients was 26 and 43 months in the LVI-positive and LVI-negative groups, respectively. Although univariate regression analysis showed significant difference between the two groups (P=0.014), multivariate regression analysis revealed that LVI was not an independent prognostic factor for overall survival in the ESCC patients (P=0.062). Lymphatic node metastasis (P=0.031), clinical stage (P=0.019), and residual tumor (P=0.026) were the independent prognostic factors. CONCLUSION: LVI labeled by D2-40 monoclonal antibody is a risk factor predictive of lymph node metastasis in ESCC patients.

Tumor-stroma ratio is an independent predictor for survival in esophageal squamous cell carcinoma.

OBJECTIVE: Tumor-stroma ratio (TSR) has been identified as a new and practicable prognostic histological characteristic of solid tumors. The aim of this study was to evaluate the prognostic value of TSR in resected esophageal squamous cell carcinoma (ESCC). METHODS: A total of 95 patients who underwent esophagectomy for ESCC were included in this study. TSR was assessed visually on the hematoxylin-eosin-stained tissue sections of surgical specimens by two independent observers. Patients with more than 50% intratumor stroma were quantified as the stroma-rich group and those with less than 50% as the stroma-poor group. RESULTS: No significant differences were observed in patient, tumor, and treatment characteristics between the stroma-rich and stroma-poor groups. The 3-year overall survival and disease-free survival rates were 64% and 57%, respectively, in the stroma-poor group, and 23% and 23%, respectively, in the stroma-rich group. Both 3-year overall and disease-free survival rates in the stroma-poor group were significantly better than those in the stroma-rich group (p < 0.01). In a multivariate analysis, TSR was identified as a highly significant prognostic factor for 3-year overall survival (hazard ratio 3.450; p = 0.001) and 3-year disease-free survival (hazard ratio 2.995; p = 0.001), independent of pTNM stage and radicality of the primary tumor. CONCLUSION: Stroma-rich tumors were associated with poor prognosis and an increased risk of relapse, which may serve as a new prognostic histological characteristic in ESCC. TSR is simple and quick to determine, is reproducible, and could be easily incorporated in routine histological evaluation.