Low level of FOXL1 indicates a worse prognosis for gastric cancer patients.

The aim of this study was to detect forkhead box L1 (FOXL1) expression in gastric cancer (GC) and to analyze its association with the prognosis of GC patients. Immunohistochemical staining, Western blotting, and quantitative reverse transcriptase polymerase chain reaction were performed to detect FOXL1 tissue expression in 109 GC patients. Clinicopathological characteristics and survival data were retrospectively analyzed to discover the clinical importance of FOXL1 expression. The chi-square test was used to analyze the relationship between FOXL1 expression and the clinicopathological characteristics. Survival curves were plotted by using the Kaplan-Meier method and compared using the log-rank test. Survival data were evaluated using univariate and multivariate Cox regression analyses. The expression of FOXL1 messenger RNA (mRNA) was significantly higher in adjacent normal samples than in the tumor tissues (P = 0.043). Clinicopathological analysis showed that FOXL1 expression was significantly correlated with depth of invasion (P = 0.017), lymph node metastasis (P = 0.019), and distant metastasis (P = 0.047). FOXL1-negative as opposed to the FOXL1-positive patients had lower 5-year overall survival (14.06 vs. 37.78 %, P < 0.001). Multivariate analysis suggested that FOXL1 expression might be an independent prognostic indicator (hazard ratio = 0.307, 95 % confidence interval, 0.187-0.505; P < 0.001) for GC patients. In conclusion, our findings provide evidence that FOXL1 might serve as a candidate tumor suppressor and a potential prognostic biomarker for GC.

Prognostic value of mixed lineage kinase domain-like protein expression in the survival of patients with gastric caner.

The aim of this study was to detect mixed lineage kinase domain-like protein (MLKL) expression in gastric cancer (GC) and to analyze its association with the prognosis of GC patients. Immunohistochemical staining, Western blotting, and quantitative reverse-transcriptase polymerase chain reaction were performed to detect MLKL tissue expression in 117 GC patients. Clinicopathological characteristics and survival data were retrospectively analyzed to discover the clinical importance of MLKL expression. The chi-square test was used to analyze the relationship between MLKL expression and the clinicopathological characteristics. Survival curves were plotted by using the Kaplan-Meier method and compared using the log-rank test. Survival data were evaluated using univariate and multivariate Cox regression analyses. The expression of MLKL mRNA was significantly higher in adjacent normal samples than in the tumor tissues (P = 0.003). Clinicopathological analysis showed that MLKL expression was significantly correlated with age (P = 0.013), histologic type (P = 0.049), differentiation grade (P < 0.001), depth of invasion (P = 0.022), and lymph node metastasis (P = 0.003). Low MLKL expression was significantly associated with decreased overall survival (median 29 months vs. 56 months, P < 0.001). Multivariate analysis suggested that MLKL expression might be an independent prognostic indicator (HR = 0.645, 95 % CI, 0.446-1.165, P = 0.002) for GC patients. In conclusion, our findings provide evidence that MLKL might serve as a candidate tumor suppressor and a potential prognostic biomarker for GC.

Autocrine Sonic hedgehog signaling promotes gastric cancer proliferation through induction of phospholipase Cγ1 and the ERK1/2 pathway.

BACKGROUND: Sonic hedgehog (SHH) plays critical roles in cell growth and development. Tumor cells express SHH, which can promote cell proliferation and epithelial-to-mesenchymal transition. However, the autocrine SHH pathway has not been described in gastric cancer. The aim of this study was to explore molecular mechanisms underlying autocrine SHH signaling in gastric cancer cells. METHODS: SHH expression was assessed using immunohistochemistry and the results were compared with clinicopathologic parameters, including survival. Using gastric cancer cell lines, we measured SHH mRNA and protein expression, and studied the effects of SHH signaling on cell proliferation and SHH secretion. We also studied the effects of an inhibitor of PLC-γ1 on phosphorylation of phospholipase Cγ1 and extracellular signal-regulated kinases (ERK)1/2. RESULTS: SHH protein expression in gastric cancer tissue was significantly higher compared with that in normal gastric tissue (P < 0.001), and the increased expression was significantly associated with pT staging (P = 0.004), pN staging (P = 0.018), pM staging (P = 0.006), and pTNM staging (P < 0.001). In multivariate analyses, overall survival in gastric cancer was significantly shorter in cases with high SHH expression (HR = 1.734, 95% CI: 1.109-2.713, P = 0.016). The AGS and SGC-7901 gastric cancer cell lines expressed SHH mRNA and protein. In these cell lines, SHH promoted carcinogenesis through activation of the PLCγ1-ERK1/2 pathway, resulting in increased cell proliferation and survival. CONCLUSIONS: Increased SHH expression is associated with shorter survival in gastric cancer patients, and SHH could represent a useful biomarker or therapeutic target for this disease.