Doublecortin-like Kinase 1 Expression Research Articles

DCLK1 is detectable in plasma of patients with Barrett's esophagus and esophageal adenocarcinoma.

Doublecortin-like kinase 1 (DCLK1), a putative tumor stem cell marker has been shown to be highly expressed in the stromal and epithelial compartments in colon and pancreatic cancer as well as Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC). To prospectively investigate whether the immunohistochemical expression of DCLK1 was associated with detectable DCLK1 plasma expression in patients with existing BE and EAC. Immunohistochemistry was performed on paraffin-embedded sections using DCLK1 antibody and scored based on staining intensity and tissue involvement. Purified human plasma samples were subjected to Western blot and ELISA analysis. Forty (40) patients were enrolled: 10 controls (normal endoscopy) and 30 with BE/EAC (13 nondysplastic BE [NDBE], 9 dysplastic BE [DBE] and 8 EAC). Mean epithelial DCLK1 staining was as follows: controls = 0.11, NDBE = 3.83, DBE = 6.0, EAC = 7.17. Mean stromal DCLK1 staining was as follows: NDBE = 5.83, DBE = 5.375, EAC = 10.83. DCLK1 was detected by plasma Western blot in 1 control and in all patients with BE/EAC p < 0.0005. Plasma DCLK1 was elevated by ELISA in EAC compared to other groups, p < 0.05. Increased expression of DCLK1 was observed in the epithelium, stroma and plasma of patients with BE/EAC. Furthermore, the presence of detectable DCLK1 in plasma of BE/EAC patients may provide a less invasive, detection tool in those patients as well as represent a novel molecular marker distinguishing between normal esophageal mucosa and BE or EAC.

Expression of doublecortin-like kinase 1 in human gastric cancer and its correlation with prognosis

To investigate the expression of doublecortin-like kinase 1(DCLK1)in gastric cancer and its prognostic significance. The expression of DCLK1 was examined by immunohistochemical staining of paraffin-embedded tumor specimens from 122 patients who underwent curative gastrectomy for gastric cancer at Peking Union Medical College Hospital between July 2002 and December 2006. Survival curves were described by the Kaplan-Meier method and compared by the Log-rank test. Univariate and multivariate analysis was performed with the Cox proportional hazard model. The expression of DCLK1 in tumor cells was significantly upregulated in 51 of 122 patients. High expression of DCLK1 in tumor cells was strongly correlated with pN stage(P=0.029)and lymphovascular invasion(P=0.029). Kaplan-Meier analysis revealed that patients with DCLK1 high expression had a significantly lower 5-year overall survival(OS)rate than that of patients with DCLK1 low expression(39. 0% vs. 65. 8%, P=0.001), as well as a significantly lower 5-year disease-free survival(DFS)rate(37. 0% vs. 64. 5%, P=0.001). Univariate and multivariate analyses showed that DCLK1 expression(both P=0.036)was an independent factor for predicting OS and DFS rate. High expression of DCLK1 in gastric cancer cells is associated with pN stage and lymphovascular invasion. It may be a predictor for poor survival in patients undergoing surgery for gastric cancer.