Risk Stratification by Tissue GAD1 Expression Level in Curatively Resected Esophageal Squamous Cell Carcinoma.

BACKGROUND/AIM: To improve patient management, new biomarkers are required that stratify prognosis. Here we focused on glutamic acid decarboxylase 1 (GAD1), which is associated with proliferation of lung cancer cells, and investigated its expression and function in esophageal squamous cell carcinoma (ESCC). MATERIALS AND METHODS: We evaluated changes in the proliferative potential of ESCC cell lines using small interfering RNA-mediated GAD1 knockdown techniques. We analyzed GAD1 protein expression using a tissue microarray (TMA) and measured GAD1 mRNA expression to evaluate correlations between the expression level of each tissue and postoperative outcomes of two independent cohorts (the TMA and mRNA cohorts) of patients who underwent radical esophagectomy. RESULTS: GAD1 knockdown reduced cell proliferation. In the TMA cohort, high GAD1 expression significantly correlated with lymph node metastasis and advanced stage. Disease-free survival was significantly shorter in the group with high GAD1 expression, as was overall survival. Multivariate analysis of overall survival showed that positivity for GAD1 was an independent prognostic factor for poor survival. In the mRNA cohort, GAD1 mRNA expression in ESCC tissues was significantly up-regulated compared with that in adjacent noncancerous mucosal tissues. When patients were divided into high- and low-expression groups according to the median GAD1 mRNA expression level in ESCC tissues, overall survival was significantly shortened in the high GAD1 expression group. The incidence of initial hematogenous recurrence was significantly higher in the group with high GAD1 expression. CONCLUSION: GAD1 expression mediates the proliferative potential of ESCC cells, and a high level may serve as a useful prognostic biomarker for patients with ESCC.

OPLAH Protein Expression Stratifies the Prognosis of Patients With Squamous Cell Carcinoma of the Esophagus.

BACKGROUND/AIM: Squamous cell carcinoma is one of the major subtypes of esophageal carcinoma, and the 5-year overall survival rate of esophageal squamous cell carcinoma patients who underwent curative treatment remains below 40%. We aimed to detect and validate the prognosticators of esophageal squamous cell carcinoma in patients who underwent radical esophagectomy. MATERIALS AND METHODS: Comprehensive analysis of transcriptome and clinical data from The Cancer Genome Atlas revealed OPLAH as one of the differentially expressed genes between esophageal squamous cell carcinoma tissues and normal esophageal mucosa. OPLAH expression changes were significantly associated with a patient prognosis. OPLAH protein levels were further evaluated by immunohisto-chemistry in esophageal squamous cell carcinoma tissues (n=177) as well as in serum samples (n=54) using ELISA. RESULTS: OPLAH mRNA was significantly overexpressed in esophageal squamous cell carcinoma tissues compared to normal esophageal mucosa, and patients with high OPLAH mRNA expression have a significantly poorer prognosis, according to The Cancer Genome Atlas data. The high staining intensity of OPLAH protein in esophageal squamous cell carcinoma tissue clearly stratified patient prognosis. According to multivariable analysis, high OPLAH protein expression was an independent prognostic factor for survival after surgery. Pre-neoadjuvant chemotherapy serum OPLAH protein concentrations were significantly associated with clinical tumor depth and node positivity and, consequently, with advanced clinical stage. The serum OPLAH protein concentration was significantly decreased by neoadjuvant chemotherapy. CONCLUSION: OPLAH protein expression in cancerous tissue and serum may have clinical utility towards stratifying prognosis of patients with esophageal squamous cell carcinoma.

Magnetic Ordering in Sr3YCo4O10+x.

Transition-metal oxides often exhibit complex magnetic behavior due to the strong interplay between atomic-structure, electronic and magnetic degrees of freedom. Cobaltates, especially, exhibit complex behavior because of cobalt's ability to adopt various valence and spin state configurations. The case of the oxygen-deficient perovskite Sr3YCo4O10+x (SYCO) has attracted considerable attention because of persisting uncertainties about its structure and the origin of the observed room temperature ferromagnetism. Here we report a combined investigation of SYCO using aberration-corrected scanning transmission electron microscopy and density functional theory calculations. Guided by theoretical results on Co-O distances projected on different planes, the atomic-scale images of several different orientations, especially of the fully oxygenated planes, allow the unambiguous extraction of the underlying structure. The calculated magnetic properties of the new structure are in excellent agreement with the experimental data.