ODZ1 allows glioblastoma to sustain invasiveness through a Myc-dependent transcriptional upregulation of RhoA

Long-term survival remains low for most patients with glioblastoma (GBM), which reveals the need for markers of disease outcome and novel therapeutic targets. We describe that ODZ1 (also known as TENM1), a type II transmembrane protein involved in fetal brain development, plays a crucial role in the invasion of GBM cells. Differentiation of glioblastoma stem-like cells drives the nuclear translocation of an intracellular fragment of ODZ1 through proteolytic cleavage by signal peptide peptidase-like 2a. The intracellular fragment of ODZ1 promotes cytoskeletal remodelling of GBM cells and invasion of the surrounding environment both in vitro and in vivo. Absence of ODZ1 by gene deletion or downregulation of ODZ1 by small interfering RNAs drastically reduces the invasive capacity of GBM cells. This activity is mediated by an ODZ1-triggered transcriptional pathway, through the E-box binding Myc protein, that promotes the expression and activation of Ras homolog family member A (RhoA) and subsequent activation of Rho-associated, coiled-coil containing protein kinase (ROCK). Overexpression of ODZ1 in GBM cells reduced survival of xenografted mice. Consistently, analysis of 122 GBM tumour samples revealed that the number of ODZ1-positive cells inversely correlated with overall and progression-free survival. Our findings establish a novel marker of invading GBM cells and consequently a potential marker of disease progression and a therapeutic target in GBM.

Microarterial sutureless sleeve anastomosis using a polymeric adhesive: an experimental study

A new technique for microarterial sutureless anastomosis that involves telescoping one vessel into the other and placing a microdrop of a polymeric adhesive (iso-propyl-cyanoacrylate) is described. Sixty-six anastomoses were performed in rat femoral arteries with a patency rate of 95 percent. Light and electron microscopic studies were conducted at regular intervals, starting immediately to 90 days postoperative. From this experimental study, it appears that the described method of anastomosis is faster and easier to perform and at least as reliable as the conventional end-to-end suture anastomosis. In addition, it was observed that tissue reaction to the glue remained primarily adventitial and did not disturb vessel patency.