Mine landslide susceptibility assessment using IVM, ANN and SVM models considering the contribution of affecting factors.

The fragile ecological environment near mines provide advantageous conditions for the development of landslides. Mine landslide susceptibility mapping is of great importance for mine geo-environment control and restoration planning. In this paper, a total of 493 landslides in Shangli County, China were collected through historical landslide inventory. 16 spectral, geomorphic and hydrological predictive factors, mainly derived from Landsat 8 imagery and Global Digital Elevation Model (ASTER GDEM), were prepared initially for landslide susceptibility assessment. Predictive capability of these factors was evaluated by using the value of variance inflation factor and information gain ratio. Three models, namely artificial neural network (ANN), support vector machine (SVM) and information value model (IVM), were applied to assess the mine landslide sensitivity. The receiver operating characteristic curve (ROC) and rank probability score were used to validate and compare the comprehensive predictive capabilities of three models involving uncertainty. Results showed that ANN model achieved higher prediction capability, proving its advantage of solve nonlinear and complex problems. Comparing the estimated landslide susceptibility map with the ground-truth one, the high-prone area tends to be located in the middle area with multiple fault distributions and the steeply sloped hill.

Survivin expression and serum levels in pancreatic cancer.

BACKGROUND: Survivin, an inhibitor of apoptosis, is overexpressed in pancreatic ductal adenocarcinoma (PDAC). Its expression is known to be associated with poor clinical outcome. However, to our knowledge, there has been no study to characterize its usefulness as a serum marker for human pancreatic cancer. Furthermore, the relation between survivin expression and the serum level of survivin has not been widely studied in PDAC. We performed this study to investigate the expression and serum level of survivin in PDAC and its clinical significance as a prognostic factor. METHODS: We performed immunohistochemical staining for survivin in formalin-fixed, paraffin-embedded blocks from 80 PDAC tissues. The serum level of survivin from the patients (n = 80) and age-matched healthy volunteers (n = 80) were analyzed by enzyme-linked immunosorbent assays (ELISAs) prior to surgical resection. Levels of expression were correlated with clinicopathological parameters. RESULTS: Serum survivin concentrations were significantly elevated in patients with PDAC when compared with healthy sera (P < 0.001). High serum survivin levels were significantly associated with perineural invasion, venous invasion, lymph node status (N stage), cell differentiation, and recurrence but not with the tumor size, age, gender of the patients, or tumor location. The median overall survival time of the group with normal serum survivin levels was longer than that of the group with elevated serum survivin. The independent factors associated with overall survival were advanced pancreatic cancer and elevated serum survivin level. Of the 80 cases of PDAC, 65 (81.25 %) were positive for survivin expression. There were significant associations between survivin expression and perineural invasion, venous invasion, and lymph node status. A significant difference in overall survival was associated with survivin expression. CONCLUSIONS: Patients with elevated serum survivin level and high survivin expression at diagnosis demonstrated a poor outcome. Detection of serum survivin or tissue survivin expression may predict the prognosis of patients with PDAC.

Gradually elevated expression of Gankyrin during human hepatocarcinogenesis and its clinicopathological significance.

Gankyrin is an important oncoprotein that is overexpressed in human hepatocellular carcinoma (HCC). However, the gradual alteration of Gankyrin in successive stages during human HCC development and the mechanism of Gankyrin-mediated hepatocarcinogenesis remain largely unknown. In this study, we evaluated the pattern and level of Gankyrin protein expression using immunohistochemistry in various liver tissues, including normal liver, chronic hepatitis, cirrhosis, adenomatous hyperplasia (AH), and HCC tissues, to analyze its clinicopathological significance. Furthermore, we stably transfected the shRNA-Gan vector, which targets human Gankyrin, into HepG2 cells to assess the role of Gankyrin in cell proliferation and tumorigenicity. The expression level of Gankyrin in the cytoplasm, nucleus, and whole cell was gradually elevated during consecutive stages of hepatocarcinogenesis. The nuclear Gankyrin level in AH was significantly higher than that in normal liver, chronic hepatitis, and cirrhotic tissues. The cytoplasmic, nuclear, and total cellular Gankyrin expression levels in HCC were significantly correlated with capsular invasion and intrahepatic metastasis. Silencing Gankyrin expression using shRNA-Gan repressed tumor cell proliferation, tumorigenicity, migration, and invasion in vitro. Our findings demonstrate that Gankyrin is aberrantly expressed beginning at the initiation stage and plays an important role in the initiation, promotion, and progression of hepatocarcinogenesis.