Prognostic value of stem cell markers in esophageal and esophagogastric junction cancer: a meta-analysis

Effect of two surgical approaches on the lung function and prognosis of patients with combined esophagogastric cancer

BACKGROUND

Adenocarcinoma of the esophagogastric junction has a center of origin within 5 cm of the esophagogastric junction. Surgical resection remains the main treatment. A transthoracic approach is recommended for Siewert I adenocarcinoma of the esophagogastric junction and a transabdominal approach is recommended for Siewert III adenocarcinoma of the esophagogastric junction. However, there is a need to determine the optimal surgical approach for Siewert II adenocarcinoma of the esophagogastric junction to improve lung function and the prognosis of patients.

AIM

To investigate and compare the surgical effects, postoperative changes in pulmonary function, and prognoses of two approaches to treating combined esophagogastric cancer.

METHODS

One hundred and thirty-eight patients with combined esophagogastric cancer treated by general and thoracic surgeries in our hospital were selected. They were divided into group A comprising 70 patients (transabdominal approach) and group B comprising 68 patients (transthoracic approach) based on the surgical approach. The indexes related to surgical trauma, number of removed lymph nodes, indexes of lung function before and after surgery, survival rate, and survival duration of the two groups were compared 3 years after surgery.

RESULTS

The duration of surgery, length of hospital stay, and postoperative drainage duration of the patients in group A were shorter than those of the patients in group B, and the volume of blood loss caused by surgery was lower for group A than for group B (P < 0.05). At the one-month postoperative review, the first second, maximum ventilation volume, forceful lung volume, and lung volume values were higher for group A than for group B (P < 0.05). Preoperatively, the QLQ-OES18 scale scores of the patients in group A were higher than those in group B on re-evaluation at 3 mo postoperatively (P < 0.05). The surgical complication rate of the patients in group A was 10.00%, which was lower than that of patients in group B, which was 23.53% (P < 0.05).

CONCLUSION

Transabdominal and transthoracic surgical approaches are comparable in treating combined esophagogastric cancer; however, the former results in lesser surgical trauma, milder changes in pulmonary function, and fewer complications.

Esophageal cancer stem cells reduce hypoxia-induced apoptosis by inhibiting the GRP78-perk-eIF2α-ATF4-CHOP pathway in vitro

Background

Due to the abnormal angiogenesis, cancer stem cells (CSCs) in esophageal cancer (EC) have the characteristics of a hypoxic microenvironment. However, they can resist hypoxia-induced apoptosis. the molecular mechanism underlying the resistance of esophageal CSCs to hypoxia-induced apoptosis is currently unclear. Therefore, this study will investigate the molecular mechanism based on CHOP-mediated endoplasmic reticulum stress.

Methods

CD44+CD24- cells in EC9706 cells were screened by fluorescence-activated cell sorting (FACS). To clarify which apoptosis pathway esophageal CSCs resist hypoxia-induced cell apoptosis through, the effects of hypoxia on apoptosis were detected by nuclear staining, flow cytometry, and JC-1 reagent, the effects of hypoxia on the expression of apoptosis-related proteins were detected by western blotting (WB) assay and quantitative polymerase chain reaction (qPCR) assay. To clarify the mechanisms of CD44+CD24- cells resistance to hypoxia-induced apoptosis is achieved by inhibiting the activation of endoplasmic reticulum stress (ERS) pathway, silenced CHOP and PERK cell lines of EC9706 cells and overexpressed CHOP and PERK cell lines of CD44+CD24- cells were constructed, the effects of hypoxia on apoptosis, cell cycle, and mitochondrial membrane potential were detected by flow cytometry and JC-1 reagent. WB assay and qPCR assay were used to detect the expressions of apoptosis-related proteins and ERS-related proteins.

Results

Hypoxia significantly induce apoptosis and cycle arrest of EC9706 cells (P<0.05), but did not affect apoptosis and cycle of CD44+CD24- cells (P>0.05). Hypoxia considerably induced the activation of mitochondrial and ERS apoptosis pathways in EC9706 cells (P<0.05), but did not affect Fas receptor apoptosis pathways (P>0.05). The three apoptosis pathways were not affected by hypoxia in CD44+CD24- cells (P>0.05). Silencing the CHOP and PERK gene inhibited hypoxia-induced apoptosis of EC9706 cells (P<0.05). CHOP and PERK overexpression promoted hypoxia-induced apoptosis of CD44+CD24- cells (P<0.05), whereas mitochondrial membrane permeability inhibitors inhibited hypoxia-induced apoptosis of CD44+CD24- cells overexpressed CHOP gene.

Conclusions

CD44+CD24- tumor stem cells in EC resist to hypoxia-induced apoptosis by the inhibition of ERS-mediated mitochondrial apoptosis pathway, which suggested that ERS pathway can serve as a potential target for reducing EC treatment resistance in clinical treatment.

High expression of guanine nucleotide-binding protein-like-3-like is associated with poor prognosis in esophageal cancer

Guanine nucleotide-binding protein-like-3-like (GNL3L) is required for processing ribosomal pre-rRNA and cell proliferation and is upregulated in many types of cancer. This study is aimed to investigate the clinical significance of GNL3L in esophageal cancer. The mRNA and protein expression levels of GNL3L were determined by using quantitative real-time polymerase chain reaction and immunohistochemistry, respectively. GNL3L was localized in both cytoplasm and nucleus. The expression levels of GNL3L in esophageal cancer tissues were significantly higher than those in adjacent nonmalignant tissues. High GNL3L expression was associated with pathologic type and poor differentiation. Patients with high GNL3L expression had shorter overall survival (OS) than those with low GNL3L expression. Multivariate Cox regression analysis revealed that GNL3L expression was an independently predictive factor for the OS of patient with esophageal cancer. The Gene Expression Profiling Interactive Analysis (GEPIA) databases also showed that GNL3L was upregulated in esophageal cancer, which was closely associated with an unfavorable prognosis of patients with esophageal cancer. Taken together, our findings suggest that GNL3L is upregulated in esophageal cancer, which is linked to the progression of the disease. As a result, GNL3L could be used as a biomarker for esophageal cancer.

Expression of CD44 and CD133 stem cell markers in squamous cell carcinoma of esophagus

Context

Role of cancer stem cells in the esophageal carcinogenesis is not clear.

Aim

To assess the expression of CD44 and CD133 cancer stem cell markers in esophageal squamous cell carcinoma (ESCC) and its predisposing lesions by immunohistochemistry.

Setting and Design

Prospective study as a part of an intramural research project.

Materials and Methods

Tissues samples were obtained with endoscopic biopsy and from surgically resected esophageal specimens. Fifty cases each of histopathologically diagnosed cases of esophageal squamous cell carcinoma and its predisposing lesions (mild, moderate, and severe dysplasia and esophagitis) were evaluated for stem cell marker CD44 and C133 by immunohistochemistry using a scoring system.

Statistical Analysis

Chi-square test, analysis of variance (ANOVA), post-hoc tests (Tukey-HSD) were used as appropriate for data analysis. Two sided P < 0.05 was considered as significant.

Results

CD44 expression was significantly higher in ESCC as compared to dysplasia and esophagitis (mean IS 7.92 ± 1.45 vs. 6.34 ± 0.80 vs 5.15 ± 0.86 respectively, P < 0.001). CD133 expression was also significantly higher in ESCC as compared to dysplasia (mean IS 6.82 ± 1.57 vs. 1.00 ± 0.00 respectively, P < 0.001) while esophagitis showed no expression. CD44 and CD133 expressions were significantly higher in poorly differentiated ESCC than moderately differentiated and well differentiated lesions (CD44 mean IS 6.94 ± 1.44 vs 8.17 ± 1.38 vs. 8.63 ± 1.02 respectively, P < 0.001 and CD 133 mean IRS 5.63 ± 0.81 vs 6.00 ± 00 vs. 9.0 ± 00 respectively, P < 0.001).

Conclusion

Significantly higher expression of CD44 and CD133 cancer stem cell markers in ESCC as compared to its predisposing lesions (esophagitis and dysplasia) suggests its role in esophageal carcinogenesis.