Cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha can play pathogenetic or protective roles in stroke. They are increased in the brain after experimental ischemia and in the CSF of patients with stroke. However, their presence in the periphery is still controversial. To determine the source and time-course of cytokines in blood of stroke patients, IL-6 and TNF-alpha release from blood cells and serum levels were determined in 40 patients on days 1 through 2, 4, 10, 30, and 90 after stroke. Twenty healthy age-matched volunteers were used as controls. IL-6 and TNF-alpha release from stimulated blood cells was increased in stroke patients, compared to controls. A peak response (+224%) was observed at day 4 for IL-6, while TNF-alpha release was largely and significantly increased (about three-fold compared to controls) from day 1 to 2 until day 90 after stroke. The increase in IL-6 release was significantly higher in ischemic, compared to hemorrhagic strokes, at days 1 and 4. Circulating IL-6 was increased at each time point. The ischemic processes in the CNS induces a long-lasting activation of IL-6 and TNF-alpha production in peripheral blood cells, which are a major source of serum cytokines after stroke.

Previously, we have identified aloe-emodin (AE) as a new type of anticancer agent, with activity that is based on apoptotic cell death promoted by a neuroectodermal tumorspecific drug uptake. We attempt to clarify the intracellular target of AE and the apoptosis-signaling pathway activated by AE in neuroblastoma cell lines. Two-photon excitation microscopy and spectroscopic titrations documented that AE is highly concentrated in susceptible cells and binds to DNA. One of the most important mediators of apoptotic response to genotoxic stimuli, such as anticancer agents, is the p53 tumor suppressor gene. To evaluate the role played by p53 in AE-induced apoptosis a p53 mutant cell line, which lacks transcriptional activity of p53 targeted genes, was tested. AE displayed a reduced growth inhibitory and proapoptotic activity in p53 mutant cells (SK-N-BE(2c)) with respect to the p53 wild-type line (SJ-N-KP). This effect was not caused by a reduced drug uptake in the mutant neuroblastoma cell line but was related to a different apoptotic cell phenotype. Whereas SJ-N-KP cells were susceptible to a p53 transcription-dependent pathway of apoptosis, SK-N-BE(2c) cells underwent apoptosis with up-regulation of p53 expression but not of p53-target genes. After AE treatment p53 translocates to the mitochondria inter-membrane space in both neuroblastoma cell lines. Due to its high accumulation in neuroectodermal tumor cells AE could also kill tumor cells harboring p53 mutant genes. This property would further contribute to AE specific anti-tumor activity and might be exploitable in the clinic.

Abstract-During the "response-to-injury" process after a mechanical insult to the porcine coronary arteries, the adventitial cells acquire the structural characteristics of myofibroblasts before being incorporated into smooth muscle (SM) layer.We assessed whether the SM-specific SM22 protein can be used as a tracer of adventitial cell-myofibroblast differentiation in the mild balloon injury of rabbit carotid artery. To achieve this goal, we used 2 monoclonal anti-SM22 antibodies (E-11 and 1-B8) and a molecular probe for the SM22␣ mRNA isoform in immunocytochemical and in situ hybridization experiments. The differentiation profile and the migratory and proliferative ability of activated adventitial cells were evaluated by a panel of antibodies to some SM and nonmuscle antigens and pulse-and end-labeling with bromo-deoxyuridine, respectively. In adventitial cells, SM22 antigenicity and SM22␣ mRNA were detectable at days 2 and 4 and, to a lesser extent, at days 7 and 21 after injury, particularly near the adventitia-media interface and mostly colocalizing with bromo-deoxyuridine-positive cells. The pulse-labeling experiments showed that the large majority of these cells penetrated the outermost layer of the tunica media without migrating to the subendothelial region. The phenotypic features of activated migrating and nonmigrating adventitial cells resembled those of vimentin-actin myofibroblast subtype and fetal-type SM cells. These findings indicate that a direct exposure of adventitia to the lumen is not required for phenotypic changes and proliferation/migration of these cells. After comparison of the SM22 expression in arterial vessels during early stages of development, we hypothesize that in the injured carotid artery the mural incorporation of adventitial cells and the spatiotemporal activation of SM22 expression are reminiscent of the vascular morphogenetic process and suggest the existence of a stem cell-like reservoir in adventitia. The early adventitial upregulation of SM22 expression in the injured vessel might be related to a multistep transition process in which nonmuscle cells are converted to myofibroblasts and, possibly, to SM cells. (Arterioscler Thromb Vasc Biol.

No abstract

The ability of viruses to selectively target, replicate within, and destroy tumour cells without deleterious effects in normal cells (oncolysis), makes the use of viruses as an attractive tool for cancer treatment. Pancreatic adenocarcinoma, being insensitive to traditional therapy and having a rather poor prognosis, represents a suitable target to evaluate viral oncolysis as a novel therapeutic approach. Herpes simplex virus (HSV) has been reported to produce an oncolytic effect in cells overexpressing Ras. As Ras signalling is frequently aberrant in pancreatic cancer, we compared four pancreatic cell lines (which differ in the presence of mutated or wild-type ras) for their ability to support growth of g34.5-replication attenuated HSV-1 (R3616). Our data show that permissiveness to viral replication is neither associated with enhanced Ras signalling nor with defective PKR activity. By contrast, we provide evidence that disregulation of the PI 3-kinase signalling pathway allows conditionally replication-defective R3616 virus to overcome the cellular antiviral activity.

The E-11 and 1-B8 monoclonal antibodies raised to the smooth muscle (SM)-specific SM22 protein from pig stomach were used to study the in vivo and in vitro phenotypic characteristics of myofibroblasts (MF) and SM cells (SMC) from the bladder detrusor muscle and serosal thickening of male rabbit. The 22-kDa SM22 band found in the SM extract appeared to be composed of distinct isoforms when examined in non-equilibrium two-dimensional gel electrophoresis (2D-EF): alpha (the most basic), beta, gamma, and delta (the most acidic) in the ratio of 34(alpha):23(beta):36(gamma):8(delta). Western blots of 2D-electrophoresed bladder extracts treated with E-11 and 1-B8 showed that alpha, beta, and delta, but not gamma isoforms were labeled with E-11, whereas alpha, beta, and gamma isoforms were stained with 1-B8. This differential immunoreactivity was not influenced by phosphorylation. The tissue distribution of SM22 immunostaining was heterogeneous in the bladder SM and serosal thickening developed as a consequence of partial outflow obstruction of the urinary bladder. At the cellular level, the 1-B8 and E-11 antibodies stained the SMC in a "diffuse" (the whole cytoplasm) and "honeycomb" (the peripheral cytoplasm) manner, whereas MF immunostaining was quite homogeneous. The two antibodies also reacted with cultured primary bladder SMC and MF grown in low serum conditions showing a heterogeneous SM22 cell distribution but an identical subcellular localization, i.e., the actin-containing filamentous network, distinguishable in part from that found in vivo. The immunocytochemical, Western blotting and 2D-EF patterns of MF from thickened serosa indicated that the gamma isoform alone is expressed in this tissue. This SM22 variant appeared before the completion of the cellular transition from MF to fully differentiated SMC. This pattern is reminiscent of bladder ontogenesis where SM22 expression in the developing bladder wall precedes that of SM myosin. Taken together these data suggest that: (i) SM22 isoforms are differently assorted in MF vs. SMC; (ii) SM22 is a SMC-lineage marker inasmuch as its expression occurs in an experimental condition characterized by a time-related cell phenotypic transition from MF to SMC, and (iii) cell conversion ability of serosal cells in the adult might take place via the reactivation of a specific "foetal" gene programme.