A novel spontaneous model of epithelial-mesenchymal transition (EMT) using a primary prostate cancer derived cell line demonstrating distinct stem-like characteristics

Cells acquire the invasive and migratory properties necessary for the invasion-metastasis cascade and the establishment of aggressive, metastatic disease by reactivating a latent embryonic programme: epithelial-to-mesenchymal transition (EMT). Herein, we report the development of a new, spontaneous model of EMT which involves four phenotypically distinct clones derived from a primary tumour-derived human prostate cancer cell line (OPCT-1), and its use to explore relationships between EMT and the generation of cancer stem cells (CSCs) in prostate cancer. Expression of epithelial (E-cadherin) and mesenchymal markers (vimentin, fibronectin) revealed that two of the four clones were incapable of spontaneously activating EMT, whereas the others contained large populations of EMT-derived, vimentin-positive cells having spindle-like morphology. One of the two EMT-positive clones exhibited aggressive and stem cell-like characteristics, whereas the other was non-aggressive and showed no stem cell phenotype. One of the two EMT-negative clones exhibited aggressive stem cell-like properties, whereas the other was the least aggressive of all clones. These findings demonstrate the existence of distinct, aggressive CSC-like populations in prostate cancer, but, importantly, that not all cells having a potential for EMT exhibit stem cell-like properties. This unique model can be used to further interrogate the biology of EMT in prostate cancer

Clinical Significance of Microvessel Count in Patients with Metastatic Liver Cancer Originating from Colorectal Carcinoma.

BACKGROUND: Microvessel count (MVC) has been correlated with patient prognosis in hepatocellular carcinoma. We investigated whether MVC assessed by staining with CD34 antibody was associated with disease-free and overall survival in patients with metastatic liver cancer (MLC). METHODS: We examined relationships between MVC and clinicopathologic factors or postoperative outcomes in 139 MLC patients who underwent hepatectomy between 1990 and 2006. CD34 expression was analyzed by the immunohistochemical method. RESULTS: MVC was associated with fibrous pseudocapsular formation on histological examination. By means of the modern Japanese classification of liver metastasis, poorer survival was associated with higher score, poorly differentiated adenocarcinoma, higher preoperative carcinoembryonic antigen (CEA) level, fibrous pseudocapsular formation, and smaller surgical margin. Shorter disease-free survival was associated with higher score when the Japanese classification of liver metastasis was used, multiple or bilobar tumor, regional lymph node metastasis in primary colon carcinoma, preoperative CEA level, fibrous pseudocapsular formation, and smaller surgical margin (/=406/mm(2)) was associated with decreased disease-free and overall survival by univariate analysis (P = .034 and P = .021, respectively), and higher MVC represented an independently poor prognostic factor in overall survival by Cox multivariate analysis (risk ratio, 2.71; P = .023) in addition to histological differentiation. CONCLUSIONS: Tumor MVC seems to be a useful prognostic marker of MLC patient survival