Type IV collagen-derived angiogenesis inhibitor: canstatin low expressing in brain-invasive meningiomas using liquid chromatography-mass spectrometry (LC-MS/MS).

PURPOSE: Brain invasion in meningiomas is considered an indicator of more aggressive behavior and worse prognosis. But the precise definition and the prognostic role of brain invasion remains unsolved duo to lacking a standardized workflow of surgical sampling and the histopathological detection. Searching for molecular biomarker expression correlating with brain invasion, could contribute to establish a molecular pathological diagnosis without problems of subjective interobserver variation and deeply understand the mechanism of brain invasion and develop innovative therapeutic strategies. METHODS: We utilized liquid chromatography tandem mass spectrometry to quantify protein abundances between non-invasive meningiomas (n = 21) and brain-invasive meningiomas (n = 21) spanning World Health Organization grades I and III. After proteomic discrepancies were analyzed, the 14 most up-regulated or down-regulated proteins were recorded. Immunohistochemical staining for glial fibrillary acidic protein and most likely brain invasion-related proteins was performed in both groups. RESULTS: A total of 6498 unique proteins were identified in non-invasive and brain-invasive meningiomas. Canstatin expression in the non-invasive group was 2.1-fold that of the brain-invasive group. The immunohistochemical staining showed canstatin expressed in both groups, and the non-invasive group showed stronger staining for canstatin in the tumor mass (p = 0.0132) than the brain-invasive group, which showed moderate intensity. CONCLUSION: This study demonstrated the low expression of canstatin in meningiomas with brain invasion, a finding that provide a basis for understanding the mechanism of brain invasion of meningiomas and may contribute to establish molecular pathological diagnosis and identify novel therapeutic targets for personalized care.

PINCH mRNA overexpression in colorectal carcinomas correlated with VEGF and FAS mRNA expression.

BACKGROUND: Particularly interesting new cysteine-histidine-rich protein (PINCH) was found to be up-regulated in the stroma of colorectal carcinomas (CRCs) in our previous studies and was involved in angiogenesis through activation of fibroblasts in extracellular matrix (ECM) in response to tumors. Here, we examined PINCH mRNA expression in colorectal cancer and investigated its relationship with the clinicopathological features and proliferation cell nuclear antigen (PCNA), vascular endothelial growth factor (VEGF) and FAS. MATERIALS AND METHODS: The primary cancer tissues, adjacent noncancerous tissues and the proximal and distant margins of normal mucosa were collected from 81 colorectal cancer patients during surgery. PINCH, PCNA, VEGF and FAS mRNA expression was examined by reverse transcriptional PCR (RT-PCR). RESULTS: PINCH mRNA expression was significantly increased in primary tumors compared with that in adjacent noncancerous tissues, and the proximal and distant margins of normal mucosa (p<0.0001). Expression of PINCH mRNA in colon cancer tended to be higher than expression in rectal cancer (p=0.051). Tumors which had infiltrated through the wall of the colorectum trended to have higher PINCH mRNA expression (p=0.073). PINCH mRNA expression in primary tumors was positively related to the expression of PCNA mRNA (r=0.534, p=0.010), VEGF mRNA (r=0.431, p=0.022) and FAS mRNA (r=0.542, p=0.012). CONCLUSION: PINCH mRNA was overexpressed in colorectal cancer and associated with PCNA mRNA, VEGF mRNA and FAS mRNA expression. PINCH mRNA was involved in the development of colorectal cancer and might play a role in the epithelial mesenchymal transition in the rectum differently than in the colon, through the adenomatous polyposis coli (APC)/catenin pathway.

Construction of novel conditional transgenic vectors for molecular therapy based on the Tet-On system and flanked with insulators in a single plasmid.

Regulated expression of a gene of interest is crucial for transgenic research, as well as for safe and efficacious gene therapy. The most commonly used conditional expression system requires the generation of two transgenic strains, one carrying an inducible promoter and the other a transactivator. The generation of conditional transgenic models using this method is costly and time consuming. In this study, we report the design and construction of novel simplified gene delivery vectors that integrate both the regulatory and responsive elements in a single vector. The Tet-On system was used and integrated the inducible promoter and transactivator in a single plasmid, between which a copy of an insulator was inserted to minimize interference between the two units. Another copy of an insulator was inserted upstream of the transgene cassette to eliminate transgene silencing and to lower basal expression. The two insulators were in the same orientation. To further decrease basal expression, the most powerful repressor domain containing a 'kruppel-associated box' of the zinc finger protein NK10 was used and fused to TetR in one of the two vectors. The function of this system was confirmed after in?vitro transient transfection. The two conditional plasmids were successfully constructed, and the expression of the gene of interest was regulated tightly in vitro. In conclusion, the vectors described here may be useful for gene therapy applications, as well as for the establishment of conditional animal models.