Voutsadakis IA. expression levels of DANCR were significantly associated with tumor size, TNM stage, lymphatic metastasis and invasion depth. DANCR knockdown inhibited the proliferation of GC cells by inducing cell cycle arrest and cell apoptosis. In addition, DANCR knockdown suppressed gastric cancer growth < 0.001) and 80.0% (52/65) GC tissues showed increased expression of DANCR compared to the adjacent normal tissues (Figure ?(Figure1B).1B). We also examined DANCR expression in normal gastric mucosa epithelial cell line (GES-1) and GC cell lines (BGC-823, L-371,257 MGC-803, HGC-27 and MKN-45). DANCR expression was also upregulated in most GC cell lines compared to that in normal gastric mucosa epithelial cell line (Figure ?(Figure1C).1C). We then analyzed the relationship between DANCR expression and the clinicopathological features. The GC patients with high expression levels of DANCR were prone to have large tumor (= 0.001), lymph node metastasis (= 0.000), GYPA invasion depth (= 0.028) and advanced TNM stage (= 0.009) (Table ?(Table1).1). We developed a receiver operating curve (ROC) to investigate the diagnostic value of DANCR in GC tissues. The area under the ROC curve (AUC) was 0.704 (95% confidence interval (CI), 0.616-0.793, < 0.001, Figure ?Figure1D)1D) and the sensitivity and specificity were 64.6% and 67.7%, respectively. Open in L-371,257 a separate window Figure 1 The relative expression levels of DANCR in the tumor tissues and serum samples of gastric cancer patients and gastric cancer cell lines(A) The relative expression levels of DANCR in gastric cancer (GC) tissues and matched adjacent normal tissues. (B) qRT-PCR analyses of DANCR expression in 65 paired GC tissues and adjacent normal tissues. The results were normalized to adjacent normal tissues and shown as log2 (2-Ct). (C) qRT-PCR analyses of DANCR expression in GC cell lines and normal gastric mucosa epithelial cells. (D) ROC curve for the diagnostic value of DANCR in the tumor tissues of gastric cancer patients. (E) qRT-PCR analyses of DANCR expression in the serum samples of gastric cancer patients (= 55) and healthy controls (= 39). (F) ROC curve for the diagnostic value of DANCR in the serum samples of gastric cancer patients. ***value= 55) and healthy controls (= 39). The results of qRT-PCR showed that the expression of DANCR in the serum of GC patients was higher than that in the serum of healthy controls (< 0.001, Figure ?Figure1E).1E). The correlation between serum DANCR expression levels and the clinicpathological characteristics was analyzed and presented in Table ?Table2.2. We found that the serum levels of DANCR were associated with tumor size (= 0.000), lymphatic metastasis (= 0.000), invasion depth (= 0.017) and TNM stage (= L-371,257 0.000). To further understand the diagnostic value of serum DANCR in GC, ROC curve was constructed. The AUC of serum DANCR was 0.816 (95% CI, 0.727-0.905, < 0.001). The level of sensitivity of serum DANCR manifestation was 72.7%, with the specificity of 79.5% (Figure ?(Figure1F).1F). Moreover, the expression level of serum DANCR in GC is definitely relatively stable (data not demonstrated). Taken collectively, these data show that the manifestation level of DANCR is definitely elevated in the tumor cells and serum of gastric malignancy patients and the improved manifestation of DANCR is definitely associated with the malignant progression of gastric malignancy. Table 2 The correlation between serum DANCR manifestation levels (CCt) and the clinicopathological characteristics of gastric malignancy individuals valueand xenograft tumor model showed the mice injected with sh-DANCR MGC-803 cells developed smaller sizes of tumors than that injected with sh-control MGC-803 cells (Number ?(Figure2D).2D). The percentage of ki-67-positive cells was reduced the tumor cells of mice in sh-DANCR group compared to that in sh-control group (Numbers ?(Numbers2E2E and ?and2F).2F). These findings suggest that DANCR knockdown inhibits the proliferation of GC cells and and < 0.05; **< 0.01; ***< 0.001. DANCR knockdown induces cell cycle arrest and cell apoptosis in GC cells We then examined the effect of DANCR knockdown on cell cycle in GC cells. The results of circulation cytometric analyses showed a decrease in the percentage of cells at S phase and an accumulation in the percentage of cells at G1 phase in DANCR knockdown organizations in comparison with control organizations (Number.