Role of cyclin E and p53 expression in progression of early gastric cancer

Background. To elucidate the role that cyclin E overexpression plays in the progression of early gastric cancer, we examined the expression of cyclin E and p53, as abnormal p53 expression is linked with cyclin E overexpression in exerting adverse affects on the cell cycle. Methods. Specimens from 108 early gastric cancers were stained by an immunohistochemical method, using anti-cyclin E and anti-p53 antibodies. Results. The positivity rate of cyclin E expression in early gastric cancer was 33% (36/108). Cyclin E-positive tumors invaded more deeply (P < 0.05), infiltrated lymphatic vessels more frequently (P < 0.01), showed a higher incidence of differentiated cancer (P < 0.01), and more often expressed p53 (P < 0.01) than cyclin E-negative tumors. Differentiated cancers showing coexpression of cyclin E and p53 were more likely to metastasize to the lymph nodes. Conclusions. Overexpression of cyclin E may promote the progression of early gastric cancer. Received for publication on Apr. 27, 1998; accepted on Nov. 17, 1998     

Comparison of short inversion time inversion recovery (STIR) and fat-saturated (chemsat) techniques for background fat intensity suppression in cervical and thoracic MR imaging

The purpose of this study was to compare short inversion time inversion recovery (STIR) fast spin-echo (FSE), and fat-saturated T2-weighted FSE sequences in terms of uniformity of fat suppression and lesion conspicuity for magnetic resonance (MR) imaging of the neck and thorax. STIR FSE and fat-saturated T2-weighted FSE images were scored for uniformity of fat suppression (n = 40) and lesion conspicuity (n = 35). Five-point rank score analyses were utilized by three experienced radiologists. The mean scores of STIR and fat-saturated FSE techniques for uniformity of fat suppression were 4.3 and 2.3, respectively (P < 0.0001). The mean scores of STIR and fat-saturated FSE techniques for lesion conspicuity were 4.2 and 3.5, respectively (P < 0.0001). Insufficient fat suppression was prominent in the mandible, supraclavicular region, anterior mediastinum, epipericardial fat, and subdiaphragmatic fat. In addition, fat-saturated T2-weighted FSE showed inadvertent water suppression in 25%. The STIR FSE technique was superior to the fat-saturated FSE technique for cervical and thoracic MR imaging.     

Tomographic features of serous retinal detachment in Vogt-Koyanagi-Harada syndrome.

To clarify the nature of serous retinal detachment in Vogt-Koyanagi-Harada (VKH) syndrome, 42 consecutive eyes of 21 patients with acute phase VKH syndrome were examined using optical coherence tomography (OCT). OCT revealed two patterns of serous retinal detachment. Twenty-nine eyes (69%) had a true retinal detachment, 17 eyes (40%) had intraretinal fluid accumulation in the outer retina, and 4 eyes had both. Intraretinal fluid accumulation appeared as an oval space in the outer retina. On fluorescein angiography, the eyes with intraretinal fluid accumulation showed more severe dye leakage from the retinal pigment epithelium.     

Role of caspase-1 subfamily in cytotoxic cytokine-induced oligodendrocyte cell death

Oligodendrocytes are myelin forming cells in mammalian central nervous system. About 50% of oligodendrocytes (OLGs) undergo cell death in normal development. In addition, OLG cell deaths have been observed in demyelinating diseases including multiple sclerosis (MS). Clinical observations and in vitro cell culture studies have suggested that cytokines mediate OLG cell damage in multiple sclerosis (MS). Among the cytokines, tumor necrosis factor (TNF) is thought to be one of the mediators responsible for the damage of OLGs in MS. The administration of TNF-alpha to primary cultures of OLGs induced DNA fragmentation, and significantly decreased the number of live OLGs. Chemical inhibitors Ac-YVAD-CHO (a specific inhibitor of caspase-1 (ICE)-like proteases) enhanced the survival of TNF-alpha treated OLGs better than Ac-DEVD-CHO (a specific inhibitor of caspase-3 (CPP32)-like proteases). These results indicate that caspase-1-mediated cell-death pathway are activated in TNF-induced OLG cell death. Caspase-11 is involved in activation of caspase-1. Oligodendrocytes from caspase-11-deficient mice are partially resistant to TNF-induced OLG cell death. Our results suggest that the inhibition of caspase-1 sufamily may be a novel therapeutic approach to treat MS.     

A case of recurrent cholangitis after bile duct injury during laparoscopic cholecystectomy: Value of scintigraphy with Tc-99m GSA and hepatobiliary scintigraphy for indication of lobectomy

A 39-year-old woman with acute cholecystitis and gallstones underwent laparoscopic cholecystectomy. She suffered from recurrent episodes of cholangitis due to injury of the major bile ducts during laparoscopic cholecystectomy. Hepatobiliary scintigraphy with Tc-99m Sn-N-pyridoxyl-5-methyltryptophan was performed. Although normal bile excretion was found from the left hepatic duct to the percutaneous transhepatic biliary drainage (PTBD) tube, excretion from the right hepatic lobe was prolonged. Scintigraphy with Tc-99m diethylenetriaminepentaacetic acid-galactosyl human serum albumin demonstrated atrophy of the right hepatic lobe and enlargement of the left hepatic lobe. Cholangiography via the PTBD tube revealed complete obstruction of the left hepatico-jejunal anastomosis and could not enhance the right intrahepatic bile duct. A right hepatic lobectomy was performed because of the atrophy, glissonitis and the absence of an appropriate bile duct for reconstruction. Postoperatively she was active and exhibited no evidence of recurrent cholangitis.     

Induction of apoptosis and cell cycle arrest by imexon in human pancreatic cancer cell lines

Imexon is an aziridine-containing small molecule currently in Phase I clinical trials. This agent has been shown to bind to thiols and increase intracellular oxidants, inducing apoptosis in hematologic cancer cells. Pancreatic cancers are known to be sensitive to oxidation, suggesting this disease may be an appropriate target for this agent. The current report examines the activity of imexon in pancreatic cells. Imexon induced concentration-dependent and time-dependent apoptosis in a panel of six human pancreatic carcinoma cell (PCC) lines. The mean IC₅₀ (SD) for growth inhibition by the SRB assay was 200 (101) µM for a 48 h exposure with a range of 64–358 µM. Cell killing was schedule-dependent, favoring exposure times ≥48 h. Imexon-treated MiaPaCa-2 cells underwent non-lethal growth arrest following exposure to concentrations ≤200 µM for 48 h. When concentrations were increased to 300 µM for ≥48 h, the MiaPaCa-2 cells arrested in G₂ phase and activated caspases 3, 8, and 9 were detected. After a 72 h exposure to the IC₈₀ concentration of imexon, cells exhibited a loss of mitochondrial membrane potential detected by CMXRos staining. However, there was no loss of reduced cellular thiols unless very high concentrations of ≥400 µM were used. In contrast, reactive oxygen species (ROS) were elevated in a dose-dependent fashion, starting at very low imexon concentrations. Imexon also significantly inhibited MiaPaCa-2 tumor growth in SCID mice at 100 mg/kg/d for 9 d. The tumor growth inhibition (% T/C) was 27% of control, and the tumor growth delay was 21 d, indicating an active agent by NCI standards. The levels of imexon that are cytotoxic in human PCC’s are achievable based on the preliminary results of the ongoing Phase I trial. Imexon appears to be active against PCCs in vitro and has an entirely novel mechanism of action involving G₂ arrest, accumulation of ROS, and the induction of apoptosis.     

An association between plasma levels of 8-isoprostane and alcohol drinking habits in Japanese volunteers]

Lipid peroxidation and oxidative stress may play a certain role in the pathogenesis of pressure-induced atherosclerosis, and alcohol related diseases. Recently, 8-isoprostane in biological fluids has been reported to be a reliable marker for lipid peroxidation and oxidative stress in vivo. In the present study, we developed an ELISA method for 8-isoprostane which has high sensitivity, intra- and inter-assay reproducibility and wide dynamic assay range. Using this method, we examined the effects of drinking and smoking habits on plasma levels of 8-isoprostane in healthy subjects. A total of 157 apparently healthy volunteers was assayed for plasma 8-isoprostane. Subjects were divided into three groups according to their alcohol consumption. Group I is non- or few-drinkers, Group II includes subjects who drink once or twice a week, and subjects of Group III intake 3 to 5 times a week or almost every day. In addition, the same population was divided into two groups, 96 non-smokers and 61 smokers. Plasma 8-isoprostane was extracted with ODS gel followed by NH2 Sep-Pak column. The 8-isoprostane fractions thus separated were assayed by a commercial ELISA kit (Cayman Chemical). The plasma 8-isoprostane was estimated to be 20.9 +/- 93 pg/ml in a total of 157 volunteers (83 male, 74 female). The plasma 8-isoprostane levels were elevated in the Group III (26.6 +/- 9.5 pg/ml) compared with Group I (20.3 +/- 6.1 pg/mL, p<0.0001) and Group II (20.9 +/- 5.7 pg/ml, p<0.001). Significant increase of the plasma 8-isoprostane was observed only in habitual drinkers of females, but not in those of males. On the other hand, no significant difference of the plasma 8-isoprostane levels were observed between non-smokers (21.5 +/- 7.3 pg/ml) and smokers (22.8 +/- 7.4 pg/ml, p>0.05). We suppose that plasma 8-isoprostane may increase in the habitual drinkers due to the oxidization stress induced by alcohol intake, and it may become a useful marker to estimate drinking habit     

Sarcoma-like tumor originating from oligodendroglioma

We present a case of sarcoma occurring at a site of resected oligodendroglioma without preceding radiotherapy or chemotherapy. Oligosarcoma occurring at sites of resected oligodendroglioma or anaplastic oligodendroglioma with sarcomatous components are rare. Although meningioma or sarcoma-like lesions are sometimes reported after glioma-targeted radiotherapy, those without preceding radiotherapy are quite rare. Moreover, cases of sarcoma without oligodendroglial components occurring at a site of resected oligodendroglioma have never been reported. In this case, fluorescent in situ hybridization analysis revealed 1p/19q co-deletion in both the first tumor and second tumors. Additionally, immunohistochemistry revealed mutated isocitrate dehydrogenase 1 in both tumors. Taken together, these findings suggest a monoclonal tumor origin. Consequently, this case may indicate a new mechanism of development of sarcomatous lesions occurring at the site of a resected glioma.