No abstract

Alterations in epithelial mucin expression are associated with carcinogenesis, but there are few data in biliary tract cancer (BTC). In pancreatic malignancy, MUC4 is a diagnostic and prognostic tumour marker, whereas MUC5AC has been proposed as a sensitive serological marker for BTC. We assessed MUC4 and MUC5AC expression in (i) prospectively collected bile and serum specimens from 72 patients with biliary obstruction (39 BTC) by real-time reverse transcriptase -PCR (qPCR) and western blot analysis, and (ii) 79 archived biliary tissues (69 BTC) by immunohistochemistry. In bile, MUC4 protein was detected in 27% of BTC and 29% of primary sclerosing cholangitis (PSC) cases, but not in other benign and malignant biliary diseases (Po0.01 and P ¼ 0.06). qPCR revealed a 1.9-fold increased MUC4 mRNA expression in BTC patients' bile compared with benign disease. In archived tissues, MUC4 protein was detected in 37% of BTC but in none of the benign samples (P ¼ 0.03). In serum, MUC5AC was found exclusively in BTC and PSC sera (44% and 13%, respectively; Po0.001 for BTC vs non-BTC) and correlated negatively with BTC survival. Biliary MUC4 and serum MUC5AC are highly specific tumour-associated mucins that may be useful in the diagnosis and formulation of therapeutic strategies in BTC.

No abstract

Stroke is a disease that affects the blood vessels that supply blood to the brain. Although platelets are implicated in the pathophysiology of stroke the mechanism is still not clear and there antiplatelet agents available for the prevention and treatment of stroke. We herein examined the relationship between the potential cytokine, TNF-α platelet activation and apoptosis in acute ischemic stroke patients. We selected 60 patients (mean age 57.9 ± 10.2 years) who had not taken any antiplatelet drugs for 14 days. A group of 45 participants (mean age 51.05 ± 9.07 years) were selected as the control group. For both the patients and for the control group, P-selectin (CD62p) and Annexin-V binding, cytochrome-c levels, caspase-3 gene expression and caspase-3 releasing and plasma TNF-α levels were measured in platelets. The results showed significant increase in plasma TNF-α and platelet Annexin-V, CD62p, cytochrome-c and caspase-3 gene expression in stroke patients compared to the control group. The data of this work suggests that inflammation may have a role in platelet apoptosis in stroke which may suggest a new aspect of the role of inflammation in the development of acute ischemic stroke.

Metal based chemotherapeutic drugs are widely used as an effective method to defeat various cancers. In this study, the mechanism of action of a novel therapeutic agent, [Pd(sac)(terpy)](sac)·4H2O (sac = saccharinate, and terpy = 2,2':6',2″-terpyridine) was studied. To better understand the proteomic changes in response to this agent, we performed nano LC-MS/MS analyses in human breast cancer cells (MDA-MB-231). Thirty proteins were identified to be differentially expressed more than 40% after drug treatment. Many cellular pathways were affected, including proteins involved in DNA repair, apoptosis, energy metabolism, protein folding, cytoskeleton, pre-mRNA maturation, or protein translation. The changes in protein expression were further verified for XRCC5, which plays a role in double strand break (DSB) repair, and ubiquitin, which is involved in protein degradation and apoptosis. The elevated XRCC5 levels were suggestive of increased DSBs. The presence of DSBs was confirmed by smearing of plasmid DNA in vitro and induction of γH2AX foci in vivo. There was also increased intracellular reactive oxygen species (ROS) formation, as detected by 2',7'-dichlorofluorescein diacetate (DCFDA) staining. Scavenging ROS by N-acetylcysteine rescued cell death in response to Pd(II) treatment, potentially explaining how the Pd(II) complex damaged the DNA. The details of this analysis and the significance will be discussed during the scope of this work.

No abstract

Hydrogels are attractive biomaterials for three-dimensional cell culture and tissue engineering applications. The preparation of hydrogels using alginate and gelatin provides cross-linked hydrophilic polymers that can swell but do not dissolve in water. In this work, we first reinforced pure alginate by using polyoxyethylene as a supporting material. In an alginate/PEO sample that contains 20 % polyoxyethylene, we obtained a stable hydrogel for cell culture experiments. We also prepared a stable alginate/gelatin hydrogel by cross-linking a periodate-oxidized alginate with another functional component such as gelatin. The hydrogels were found to have a high fluid uptake. In this work, preparation, characterization, swelling, and surface properties of these scaffold materials were described. Lyophilized scaffolds obtained from hydrogels were used for cell viability experiments, and the results were presented in detail.

Metal-based compounds represent promising anticancer therapeutic agents. In this study, the mechanism of action of a novel metal-based drug, a palladium(II) (Pd) complex ([PdCl(terpy)](sac)·2H2O, terpy=2,2':6',2''-terpyridine and sac=saccharinate), was elucidated. The tested compound induced cytotoxicity in nine different human cancer cell lines that originated from various organs, suggesting a broad spectrum of activity. The IC50 values were significantly higher for noncancerous cells when compared with cancer cells. We found that cells treated with the Pd(II) complex exhibited increased caspase 3/7 activities and condensed/fragmented nuclei, as demonstrated by nuclear staining and DNA laddering. Morphological features, such as cellular shrinkage and blebbing, were also observed, indicating that apoptosis was the primary mechanism of cell death. Pd(II) treatment induced DNA double-stranded breaks both in vitro and in vivo, potentially accounting for the source of stress in these cells. Although caspase 3/7 activities were elevated after Pd(II) treatment, silencing or using inhibitors of caspase 3 did not block apoptosis. Other molecules that could potentially play a role in Pd(II)-induced apoptosis, such as p53 and Bax, were also tested using silencing technology. However, none of these proteins were essential for cell death, indicating either that these molecules do not participate in Pd(II)-induced apoptosis or that other pathways were activated in their absence. Hence, this new molecule might represent a promising anticancer agent that exhibits cytotoxicity in p53-mutant, Bax-mutant, and/or caspase 3-mutant cancer cells.