Association of CD94/NKG2A, CD94/NKG2C, and its ligand HLA-E polymorphisms with Behcet's disease

Inhibitory CD94/NKG2A and activating CD94/NKG2C receptors are expressed on natural killer, CD4, and CD8 T cells and recognize human leukocyte antigen (HLA)-E, resulting in the modulation of cytotoxic activity and cytokine production. An imbalance in cytotoxic activity and cytokine production has been implicated in Behcet's disease (BD). The results of this study showed that the NKG2A c.-4258*C, c.338-90*G, and CD94 c.-134*T alleles (P= 0.015, OR = 0.8; P < 0.0001, OR = 0.5; and P= 0.034, OR = 0.8, respectively) were associated with decreased risk and that NKG2A c.284-67_-62del, c.1077*C, and the activating receptor, NKG2C c.305*T were not associated with 345 patients with BD. But a significant difference in NKG2C c.305*T was detected among BD patients with ocular lesions and arthritis (P < 0.0001, OR = 2.1 and P= 0.0001, OR = 1.8, respectively). We already showed in our previous research that HLA-E*0101 also appears to contribute to a reduction in risk through the inhibitory CD94/NKG2A-mediated immune response. This result led us to the analyses of the combined risk of the HLA-E and the NKG2A for BD. Individuals harboring HLA-E*0101, NKG2A c.-4258*C, and c.338-90*G evidenced a reduced risk of BD compared with healthy controls (21.1% vs 40.1%, P < 0.0001, OR = 0.4). By way of contrast, individuals without the HLA-E*0101, NKG2A c.-4258*C, and c.338-90*G alleles evidenced a twofold increased risk of BD (P= 0.014, OR = 2.0). Individuals without HLA-E*0101, NKG2A c.-4258*G/*G, and c.338-90*G evidenced a 4.8-fold increase in BD risk (P= 0.0002, OR = 4.8). Although the effects of these single nucleotide polymorphisms (SNPs) remain unclear, our results indicate that the SNPs of the inhibitory receptor CD94/NKG2A and its haplotypes, as well as its ligand HLA-E, are associated with BD immune systems.

Using pCIN-mIL-4 DNA vector to express mRNA and protein and to improve herpes simplex virus-induced Behcet's disease symptoms in mice

Behcet's disease (BD) is a chronic, recurrent, inflammatory, multisystemic disorder characterized primarily by vasculitis. The etiopathogenesis of BD involves immunogenetics, infectious organisms (streptococcus, herpes simplex virus), immunoregulation and vascular dysfunctions. We previously found that immunoregulation associated with viral infection was important to the development of BD-like symptoms. Recently, we demonstrated that Th2 cytokines up-regulated by Th2 adjuvant were efficient in attenuating or improving these BD-like symptoms. In order to directly augment IL-4 expression, a DNA vector (pCIN-mIL-4) was administered to BD-like mice using the Helios gene gun system. Two injections of the pCIN-mIL-4 vector, spread over 2 weeks, attenuated or improved the mucocutaneous symptoms of 10 out of 12 BD-like mice in our study. The improved mucocutaneous symptoms were crust in face, ulcer in mouth, scruff, back, genital and erythema. This improvement also correlated with induction of IL-4 mRNA in lymph nodes, protein in serum and intracellular IL-4 staining in splenocytes. Normal control mice (n = 10) injected with the pCIN-mIL-4 vector expressed IL-4 mRNA and showed more splenocytes stained with anti-IL-4 antibody (5.77 +/- 0.92%) than did mice injected with the pCIN control vector (3.34 +/- 0.25%; p = 0.02). These findings indicate that an IL-4 DNA vector could be used to express mRNA and protein in vivo and further suggest that such an IL-4 DNA vector could be used as a therapeutic treatment in recurrent inflammation shifted to T helper type 1 cytokine production.

Sodium selenite induces superoxide-mediated mitochondrial damage and subsequent autophagic cell death in malignant glioma cells

Malignant gliomas are resistant to various proapoptotic therapies, such as radiotherapy and conventional chemotherapy. In this study, we show that selenite is preferentially cytotoxic to various human glioma cells over normal astrocytes via autophagic cell death. Overexpression of Akt, survivin, XIAP, Bcl-2, or Bcl-xL failed to block selenite-induced cell death, suggesting that selenite treatment may offer a potential therapeutic strategy against malignant gliomas with apoptotic defects. Before selenite-induced cell death in glioma cells, disruption of the mitochondrial cristae, loss of mitochondrial membrane potential, and subsequent entrapment of disorganized mitochondria within autophagosomes or autophagolysosomes along with degradation of mitochondrial proteins were noted, showing that selenite induces autophagy in which mitochondria serve as the main target. At the early phase of selenite treatment, high levels of superoxide anion were generated and overexpression of copper/zinc superoxide dismutase or manganese superoxide dismutase, but not catalase, significantly blocked selenite-induced mitochondrial damage and subsequent autophagic cell death. Furthermore, treatment with diquat, a superoxide generator, induced autophagic cell death in glioma cells. Taken together, our study clearly shows that superoxide anion generated by selenite triggers mitochondrial damage and subsequent mitophagy, leading to irreversible cell death in glioma cells.

Alemtuzumab plus CHOP as front-line chemotherapy for patients with peripheral T-cell lymphomas

8069

Background: The present study was conducted to evaluate the safety and efficacy of alemtuzumab plus CHOP chemotherapy for patients with peripheral T-cell lymphomas (PTCLs). Methods: Twenty patients with newly diagnosed PTCLs were enrolled. The treatment consisted of classical CHOP plus alemtuzumab (10 mg/m2 i.v on day 1 and 20 mg/m2 i.v on day 2 in the first cycle, then 30 mg/m2 i.v on day 1 in the subsequent cycles) based on 3-week intervals. Results: Thirteen complete responses (65.0%) and 3 partial responses (15.0%) were confirmed, giving an overall response rate of 80.0 %. The estimated event-free survival at 1 year was 43.3%. The most severe hematologic adverse event was neutropenia, which occurred with a grade 4 intensity in 18 patients (90.0%). Plus, febrile neutropenia was observed in 11 patients (55.0%). Five patients (25%) experienced CMV (cytomegalovirus) reactivation, while 3 patients developed CMV diseases, such as pneumonitis or retinitis. There were 2 treatment-related deaths. Conclusions: The alemtuzumab plus CHOP chemotherapy seemed to produce active antitumor activity in terms of the complete response rates in patients with PTCLs. However, since high infectious and hematologic toxicities were observed, careful monitoring and early treatment to prevent treatment-related mortality are needed.

No significant financial relationships to disclose.

Vascular endothelial growth factor (VEGF) gene polymorphisms associated with prognosis for patients with colorectal cancer

4125

Background: Vascular endothelial growth factor (VEGF) or its family may be considered to play an important role in lymphangiogenesis and lymphatic tumor spread, thereby affecting prognosis of colorectal cancer. Accordingly, the present study analyzed VEGF gene polymorphisms and their impact on the prognosis for patients with colorectal cancer. Patients and Methods: Four hundred and sixty-five consecutive patients with surgically treated colorectal adenocarcinoma were enrolled in the present study. The genomic DNA was extracted from fresh colorectal tumor tissue and 3 VEGF (-2578C > A, -634G > C, and +936C > T) gene polymorphisms determined using a PCR/DHPLC (Polymerase chain reaction/Denaturing high-performance liquid chromatography) assay. Results: The median age of the patients was 64 years (range, 21–89), and 264 (56.7%) patients had colon cancer and 201 (48.2%) patients rectal cancer. Pathologic stages evaluable (n=464) after surgery were as follows: stage I (n=79, 17.0%), stage II (n=157, 33.8%), stage III (n=157, 33.8%), and stage IV (n=71, 15.3%). Multivariate survival analysis including stage, differentiation, and CEA level showed that survival for patients with the -634CC (overall survival [OS]: hazard ratio [HR]=0.175, P<0.001; progression-free survival [PFS]: HR=0.554, P=0.040) or GC genotype (OS: HR=0.158, P<0.001; PFS: HR=0.630, P=0.044) were better than for patients with the -634GG genotype, whereas the +936TT (OS: HR=65.959, P<0.001; PFS: HR=2.823, P=0.016) or CT genotype (OS: HR=16.116, P<0.001; PFS: HR=3.507, P<0.001) were associated with a worse survival compared to the CC genotype. In haplotype analysis, the -2578A/-634G/+936T haplotype exhibited a significantly worse survival when compared to the wild -2578C/-634G/+936C haplotype (OS: HR=4.670, P<0.001; PFS: HR=3.624, P<0.001). Conclusions: VEGF gene polymorphisms were found to be an independent prognostic marker for patients with colorectal cancer. Accordingly, the analysis of VEGF gene polymorphisms can help identify patient subgroups at high risk of a poor disease outcome.

No significant financial relationships to disclose.

HLA-E*0101 and HLA-G*010101 reduce the risk of Behcet's disease

The nonclassical human leukocyte antigen (HLA)-E and -G molecules have previously been shown to inhibit natural killer- and cytotoxic T-lymphocyte-mediated cell lysis and have also been shown to prevent the proliferation of CD4 T cells and secrete cytokines that appear to be important in the modulation of the Behcet's disease (BD) immune systems. Polymorphisms in the HLA-E and HLA-G genes have been associated with differential expression and function. Thus, we conducted an analysis of the HLA-E and HLA-G alleles using Amplification Refractory Mutation System-polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism techniques in a study comprising 312 patients with BD and 486 controls. The HLA-E*0101 and HLA-G*010101 alleles were associated with a reduced risk of BD (P = 0.0002, odds ratio (OR) = 0.7 and P = 0.002, OR = 0.7, respectively). By way of contrast, the variants HLA-E*010302, HLA-G*010102, G*0105N alleles and 3741_3754ins14bp were all associated with an increased risk of BD (P < 0.0001, OR = 1.6; P = 0.002, OR = 1.8; P = 0.024, OR = 2.0 and P = 0.003, OR = 1.4, respectively). Individuals carrying both the HLA-E*0101 and the HLA-G*010101 alleles evidenced significantly lower frequency in the patients than in the controls (35.6% vs 49.6%; P < 0.0001, OR = 0.6). These results indicate that variant HLA-E and HLA-G molecules appear to function independently and synergistically, increasing the risk of BD, and may result in an imbalance of lymphocytic functions, which may culminate in the development of BD.

Hepatitis B virus x protein induces perinuclear mitochondrial clustering in microtubule- and Dynein-dependent manners

The hepatitis B virus (HBV) X protein (HBx) is thought to play a key role in HBV replication and the development of liver cancer. It became apparent that HBx induces mitochondrial clustering at the nuclear periphery, but the molecular basis for mitochondrial clustering is not understood. Since mitochondria move along the cytoskeleton as a cargo of motor proteins, we hypothesized that mitochondrial clustering induced by HBx occurs by an altered intracellular motility. Here, we demonstrated that the treatment of HBx-expressing cells with a microtubule-disrupting drug (nocodazole) abrogated mitochondrial clustering, while the removal of nocodazole restored clustering within 30 to 60 min, indicating that mitochondrial transport is occurring in a microtubule-dependent manner. The addition of a cytochalasin D-disrupting actin filament, however, did not measurably affect mitochondrial clustering. Mitochondrial clustering was further studied by observations of HBV-related hepatoma cells and HBV-replicating cells. Importantly, the abrogation of the dynein activity in HBx-expressing cells by microinjection of a neutralizing anti-dynein intermediate-chain antibody, dynamitin overexpression, or the addition of a dynein ATPase inhibitor significantly suppressed the mitochondrial clustering. In addition, HBx induced the activation of the p38 mitogen-activated protein kinase (MAPK) and inhibition of the p38 kinase activity by SB203580-attenuated HBx-induced mitochondrial clustering. Taken together, HBx activation of the p38 MAPK contributed to the increase in the microtubule-dependent dynein activity. The data suggest that HBx plays a novel regulatory role in subcellular transport systems, perhaps facilitating the process of maturation and/or assembly of progeny particles during HBV replication. Furthermore, mitochondrion aggregation induced by HBx may represent a cellular process that underlies disease progression during chronic viral infection.

Pilot remission induction therapy with idarubicin, plus intensified dose of Ara-C and priming with granulocyte colony-stimulating factor for acute myeloid leukemia

16516

Background: The sensitization of leukemic cells with hematopoietic growth factors can enhance the cytotoxicity of chemotherapy in acute myeloid leukemia (AML). Intensified remission induction (RI) therapy can also improve the treatment results for AML. Therefore, the current trial attempted to evaluate the efficacy and toxicity of granulocyte colony-stimulating factor (G-CSF) priming and a dose intensification of Ara-C in RI chemotherapy for AML. Methods: A total of 29 patients with newly diagnosed AML received G-CSF-priming RI chemotherapy consisting of idarubicin (12 mg/m2, D1–3), G-CSF (150 ug/m2, D3–8), and Ara-C (500 mg/m2, bid, D4–8), and the outcomes were compared with those for a historical group treated with a standard regimen consisting of idarubicin (12 mg/m2, D1–3) and Ara-C (100 mg/m2, D1–7). Results: There was no difference in the sex, age, subtype, and cytogenetic risk between the two groups. The complete remission (CR) rate and treatment-related mortality (TRM) were 72% and 17% for G-CSF-primed group and 71% and 10% for the historical group, respectively (p = 0.89 and p = 0.32). The time to neutrophil and platelet recovery did not differ significantly between the two groups (25 days vs. 24 days, p=0.17; 24 days vs. 23 days, p = 0.23, respectively). Similarly, the duration of fever was also not significantly different (5 days vs. 7 days, p = 0.58). Thirteen patients (45%) experienced fever and 5 patients (17%) manifested skin rashes during the G-CSF priming. After a median follow-up of 336 days, the 1-year overall survival (OS), disease-free survival (DFS), and event-free survival (EFS) rates were 72% vs. 63% (p = 0.83), 74% vs. 56% (p = 0.059), and 53% vs. 38% (p = 0.32), respectively. Conclusion: The G-CSF-priming RI regimen with an intensified dose of Ara-C did not show a superior efficacy when compared with a standard regimen, yet did produce a slightly longer DFS. Therefore, the sensitization of leukemic cells with growth factors and dose intensification would only seem to be a clinically applicable means to enhance the efficacy of RI chemotherapy in selected patients with AML, thereby warranting further studies focusing on specific subgroups of AML patients.

No significant financial relationships to disclose.

Phase II study of capecitabine and irinotecan combination chemotherapy in patients with advanced gastric cancer

14037

Background: Several studies have shown the efficacy of capecitabine and irinotecan combination chemotherapy for advanced colorectal cancer, while no results have yet been reported for advanced gastric cancer. Accordingly, the current study evaluated the efficacy and safety of a combination regimen of capecitabine plus irinotecan in patients with advanced gastric cancer. Methods: Patients with previously untreated metastatic or recurrent, measurable gastric cancer received oral capecitabine 1000 mg/m2 twice daily from day 1 to 14 and intravenous irinotecan 100 mg/m2 on days 1 and 8, based on a 3-week cycle. Results: Forty-one patients were enrolled in the current study, among whom 38 were assessable for efficacy and 40 assessable for toxicity. Three complete responses and 16 partial responses were confirmed, giving an overall response rate of 46.3%. At a median follow-up of 269 days, the median time to progression and overall survival were 5.1 months and 8.6 months, respectively. Grade 3/4 neutropenia occurred in 4 patients and grade 3 febrile neutropenia was observed in 2 patients. Grade 3 diarrhea and grade 2 hand-foot syndrome occurred in 6 patients and 8 patients, respectively. Conclusions: The combination of capecitabine and irinotecan was found to be well tolerated and effective in patients with advanced gastric cancer. Accordingly, this regimen can be regarded as an important first-line treatment option for advanced gastric cancer.

No significant financial relationships to disclose.

Vascular endothelial growth factor (VEGF) polymorphism is associated with prognosis of patients with gastric cancer

4019

Background: Recent studies demonstrated that the expression of vascular endothelial growth factor (VEGF) family had a prognostic significance in patients with gastric cancer. The present study analyzed VEGF polymorphism and its impact on prognosis in patients with gastric cancer. Methods: Five hundred three consecutive patients with surgically resected gastric adenocarcinoma at a single institution between January 2000 and December 2001 were enrolled into the study. Genomic DNA was extracted from paraffin-embedded tumor tissue and four VEGF (-460T > C, +405C > G, 936C> T, and -1154G > A) genotypes were determined using a PCR-RFLP assay. Results: The median age of patients was 60.0 years (range, 25–83 years), and 337 (67.0%) patients were male. Pathologic stages after resection were as follows: stage 0 (n=6, 1.2%), stage I (n=277, 55.1%), stage II (n=105, 20.9%), stage III (n=74, 14.7%), and stage IV (n=41, 8.2%). The estimated 5-year disease-free survival (DFS) rates according to stage were significantly different (p < 0.0001). Three VEGF polymorphisms (+405C > G, 936C, and -1154G > A > T) were not associated with survival of patients, while -460T > C polymorphism had a prognostic significance. In patients with early stage gastric cancer (stage 0 or 1, n=283), the estimated 5-year DFS and carcinoma-specific survival (CSS) for patients with homozygous genotype (CC or TT) of -460T > C were superior to those for heterozygous genotype (CT) (98.1% versus 90.3%, p=0.0047; 98.1% versus 92.5%, p=0.0284). In Cox multivariate regression, stage and VEGF -460T > C genotype were an independent prognostic factors for both DFS (p=0.007; p=0.010) and CSS (p=0.013; p=0.038). Conclusions: VEGF -460T > C polymorphism was found to be an independent prognostic marker for patients with curatively resected early stage gastric adenocarcinoma. Accordingly, VEGF -460T > C polymorphism can help to identify patients with unfavorable clinical outcome and thereby may be useful to refine therapeutic decisions in early stage gastric cancer.

No significant financial relationships to disclose.

Cost of Moderate to Severe Plaque Psoriasis in Germany: A Multicenter Cost-of-Illness Study

BACKGROUND

There is little information concerning the costs of psoriasis and patients' quality of life (QoL) in Germany.

OBJECTIVE

To obtain data on the annual costs and QoL(to follow in a further publication) of patients with moderate to severe plaque psoriasis.

METHODS

Between October 2003 and February 2004, six office-based dermatologists and eight dermatology outpatient departments retrospectively documented cost-of-illness data from a societal cost perspective in 184 patients over a 12-month period. Patients were stratified into three subgroups according to their treatment scheme.

RESULTS

Mean total costs amounted to euro 6,709 per patient and year. The mean PASI score was 18.2 and PBSA 28.9%. Annual costs were highest with euro 8,831 in high-need patients. They also showed the highest PASI score (22.2).

CONCLUSION

Moderate to severe plaque psoriasis is associated with tremendous costs, particularly in patients not adequately controlled by conventional therapies, while the outcomes of patients were unsatisfactory.

Differential responses of the growth hormone axis in two rat models of streptozotocin-induced insulinopenic diabetes

The impact of streptozotocin (STZ)-induced, insulinopenic diabetes on the GH axis of rats and mice differs from study to study, where this variation may be related to the induction scheme, severity of the diabetes and/or the genetic background of the animal model used. In order to begin differentiate between these possibilities, we compared the effects of two different STZ induction schemes on the GH axis of male Sprague-Dawley rats: (1) a single high-dose injection of STZ (HI STZ, 80 mg/kg, i.p.), which results in rapid chemical destruction of the pancreatic beta-cells, and (2) multiple low-dose injections of STZ (LO STZ, 20 mg/kg for 5 consecutive days, i.p.), which results in a gradual, autoimmune destruction of beta-cells. STZ-treated animals were killed after 3 weeks of hyperglycemia (>400 mg/dl), and in both paradigms circulating insulin levels were reduced to <40% of vehicle-treated controls. HI STZ-treated rats lost weight, while body weights of LO STZ-treated animals gradually increased over time, similar to vehicle-treated controls. As previously reported, HI STZ resulted in a decrease in circulating GH and IGF-I levels which was associated with a rise in hypothalamic neuropeptide Y (NPY) mRNA (355% of vehicle-treated controls) and a fall in GH-releasing hormone (GHRH) mRNA (45% of vehicle-treated controls) levels. Changes in hypothalamic neuropeptide expression were reflected by an increase in immunoreactive NPY within the arcuate and paraventricular nuclei and a decrease in GHRH immunoreactivity in the arcuate nucleus, as assessed by immunohistochemistry. Consistent with the decline in circulating GH and hypothalamic GHRH, pituitary GH mRNA levels of HI STZ-treated rats were 58% of controls. However, pituitary receptor mRNA levels for GHRH and ghrelin increased and those for somatostatin (sst2, sst3 and sst5) decreased following HI STZ treatment. The impact of LO STZ treatment on the GH axis differed from that observed following HI STZ treatment, despite comparable changes in circulating glucose and insulin. Specifically, LO STZ treatment did suppress circulating IGF-I levels to the same extent as HI STZ treatment; however, the impact on hypothalamic NPY mRNA levels was less dramatic (158% of vehicle-treated controls) where NPY immunoreactivity was increased only within the paraventricular nucleus. Also, there were no changes in circulating GH, hypothalamic GHRH or pituitary receptor expression following LO STZ treatment, with the exception that pituitary sst3 mRNA levels were suppressed compared with vehicle-treated controls. Taken together these results clearly demonstrate that insulinopenia, hyperglycemia and reduced circulating IGF-I levels are not the primary mediators of hypothalamic and pituitary changes in the GH axis of rats following HI STZ treatment. Changes in the GH axis of HI STZ-treated rats were accompanied by weight loss, and these changes are strikingly similar to those observed in the fasted rat, which suggests that factors associated with the catabolic state are critical in modifying the GH axis following STZ-induced diabetes.

Cytopathic changes and pro-inflammatory cytokines induced by Naegleria fowleri trophozoites in rat microglial cells and protective effects of an anti-Nfa1 antibody

Naegleria fowleri, a free-living amoeba, causes fatal primary amoebic meningoencephalitis in experimental animals and humans. The nfa1 gene (360 bp) was previously cloned from a cDNA library of pathogenic N. fowleri by immunoscreening, and produced a 13.1-kDa recombinant protein that showed pseudopodia-specific localization by immunocytochemistry. On the basis of an idea that the pseudopodia-specific Nfa1 protein seems to be involved in the pathogenicity of N. fowleri, the cytopathic activity of N. fowleri trophozoites co-cultured with rat microglial cells was observed, and the effects of an anti-Nfa1 antibody in a co-culture system were elucidated. Using light, scanning and transmission electron microscopy, it was seen that N. fowleri trophozoites in contact with microglial cells produced vigorous pseudopodia and a food-cup structure. Microglial cells were destroyed by N. fowleri trophozoites as seen from necrotic cell death in a time-dependent manner. In a(51)Cr release assay, N. fowleri showed 17.8%, 24.9%, 54.6% and 98% cytotoxicity against microglial cells at 3, 6, 12 and 24 h post-incubation, respectively. However, when anti-Nfa1 antibody was added in a coculture system, N. fowleri cytotoxicity was reduced to 15.5%, 20.3%, 46.7% and 66.9%, respectively. Moreover, microglial cells co-cultured with N. fowleri trophozoites secreted the pro-inflammatory cytokines, TNF-alpha, IL-1beta and IL-6. In the presence of anti-Nfa1 antibody, the secretion of TNF-alpha was slightly, but not significantly, decreased.

Immobilization stress induces cell death through production of reactive oxygen species in the mouse cerebral cortex

Prolonged stress has been shown to impair brain function and increase vulnerability to neuronal injury. To elucidate the in vivo response of neuronal cells to induced stress, we immobilized mice by binding their legs. Levels of reactive oxygen species (ROS) in the cerebral cortex were increased after stress induction. NADPH oxidase, interleukin-1beta (IL-1beta) and cyclooxygenase 2 mRNA (COX-2) expression levels were upregulated, and Fas levels were also increased. The increased expression of these factors was associated with neuronal death, which was confirmed by TUNEL and NeuN staining. OX42 staining was also evident around the TUNEL-stained lesions. From these findings, it appears that immobilization stress induces neuronal death in the mouse cerebral cortex, a process mediated by NADPH oxidase, IL-1beta, COX-2, ROS and Fas. However, this could be inhibited by pretreating the animals with antioxidants such as ebselen or pyrrolidine dithiocarbamate.

Two distinct modes of cell death induced by doxorubicin: apoptosis and cell death through mitotic catastrophe accompanied by senescence-like phenotype

Chronic exposure of many human hepatoma cell lines to a low dose (LD) of doxorubicin induced a senescence-like phenotype (SLP) accompanied by enlargement of cells and increased senescence-associated beta-galactosidase activity. LD doxorubicin-induced SLP was preceded by multinucleation and downregulation of multiple proteins with mitotic checkpoint function, including CENP-A, Mad2, BubR1, and Chk1. LD doxorubicin-treated cells eventually underwent cell death through mitotic catastrophe. When we investigated whether LD doxorubicin-induced cell death shares biochemical characteristics with high dose (HD) doxorubicin-induced apoptosis in Huh-7 cells, we observed that externalization of phosphatidyl serine and release of mitochondrial cytochrome c into the cytosol was associated with both types of cell death. However, propidium iodide exclusion assays showed that membrane integrity was lost in the initial phase of LD doxorubicin-induced cell death through mitotic catastrophe, whereas it was lost during the late phase of HD doxorubicin-induced apoptosis. Furthermore, HD doxorubicin-induced apoptosis but not LD doxorubicin-induced mitotic catastrophe led to transient activation of NF-kappaB and strong, sustained activations of p38, c-Jun N-terminal kinase, and caspases. Collectively, these results indicate that different doses of doxorubicin activate different regulatory mechanisms to induce either apoptosis or cell death through mitotic catastrophe.

Caspase-3-mediated cleavage of PHF-1 tau during apoptosis irrespective of excitotoxicity and oxidative stress: an implication to Alzheimer's disease

Excitotoxicity, oxidative stress, and apoptosis have been recognized as routes to neuronal death in various neurological diseases. We examined the possibility that PHF-1 tau, a substrate for various proteases, would be selectively cleaved depending upon routes of neuronal death. Cleavage form of PHF-1 tau was not observed in cortical cell cultures exposed to excitotoxins or oxidative stress that cause neuronal cell necrosis. PHF-1 tau was cleaved within 8 h following exposure of cortical cell cultures to apoptosis-inducing agents. This cleavage was blocked by inclusion of zDEVD-fmk, an inhibitor of caspase-3, and accompanied by activation of caspase-3. Levels and cleavage of PHF-1 tau were markedly increased in AD brain compared with control. Moreover, PHF-1 tau and active caspase-3 were colocalized mostly in tangle-bearing neurons. The current findings suggest that PHF-1 tau is cleaved by caspase-3 during apoptosis and neurodegenerative process in AD.

Novel antioxidant ameliorates the fibrosis and inflammation of cerulein-induced chronic pancreatitis in a mouse model

BACKGROUND/AIM

Oxygen free radicals (OFRs) mediate an important step in the initiation of experimental acute pancreatitis and several clinical findings suggested the possible contribution of OFRs to the pathogenesis of pancreatic fibrosis. So far, there are no studies which reporting potential role of OFRs in development of chronic pancreatitis with the prevention with antioxidants. This study was aimed to establish the mice model of chronic fibrosing pancreatitis and to prove the involvement of OFRs in chronic pancreatitis with fibrosis.

METHODS

Repeated intraperitoneal cerulein injection was performed to induce chronic pancreatitis in mice. Histological changes in the pancreas were examined, and markers for oxidative stress were measured in the pancreatic tissue and serum of the mice. DA-9601, a phytochemical possessing anti-inflammatory and antioxidative action, was given together with cerulein to the mice.

RESULTS

Repeated intraperitoneal injection of cerulein provoked significant severity of chronic fibrosing pancreatitis after 5 weeks. After treatment of DA-9601, the extents of pancreatic fibrosis were statistically significantly decreased in accordance with lessened pancreatic inflammations. The NF-kappaB binding activities were increased in chronic pancreatitis, which were significantly attenuated after DA-9601 treatment. The levels of myeloperoxidase and iNOS activities were also significantly decreased in DA-9601-treated group compared to the pancreatitis only group. Cytoprotective proteins such as heat shock protein-70 (HSP) and metallothionein were significantly increased in the DA-9601-treated group. DA-9601 decreased the expressions of alpha-SMA and type I collagen in cultured pancreatic stellate cells.

CONCLUSIONS

Oxidative stress was principally involved in the pathogenesis of chronic pancreatitis with fibrosis.

Therapeutic effects of gemcitabine on cutaneous manifestations in an Adamantiades-Behçet's disease-like mouse model

The aim of this work was to study the effects and side effects of gemcitabine (2',2'-difluorodeoxycytidine, dFdC), a pyrimidine synthesis inhibitor, on skin lesions of a herpes simplex virus (HSV)-induced Adamantiades-Behçet's disease (ABD)-like mouse model. For the dose-escalation study, ICR mice were treated intraperitoneally with dFdC over 5 days. For the efficacy study, ICR mice were inoculated with HSV and classified as having ABD according to a revised Japanese classification, and then 18 ABD mice were randomly assigned to placebo, 0.06 or 0.12 microg of dFdC/day over 5 days. Serum levels of interleukin-4 (IL-4), IL-6, IL-10, interferon-gamma (IFN-gamma), and tumor necrosis factor-alpha (TNF-alpha) were determined using enzyme-linked immunosorbent assay. After application of 3 microg of dFdC over 5 days, alanine aminotransferase increased (P = 0.032), but all other kidney and liver parameters were unchanged. In ABD mice, 5 days of dFdC treatment with 0.06 or 0.12 microg of dFdC/day resulted in a dose-dependent improvement of cutaneous manifestations by more than 60% (P = 0.017). There was no significant change in cytokine levels, and none of the cytokine levels correlated with response to treatment. Moreover, dFdC shows promising effects to improve cutaneous lesions in the HSV-induced ABD-like mouse model. In this animal model, effects of dFdC on the cytokine profile remained inconclusive.

Thalidomide upregulates macrophage inflammatory protein-1alpha in a herpes simplex virus-induced Behçet's disease-like animal model

The mechanism of action of thalidomide in the treatment of patients with Behçet's disease (BD) is poorly understood. There is some evidence to suggest that certain immunological abnormalities are associated with the pathogenesis of BD. A BD-like mouse model induced by herpes simplex virus (HSV) inoculation shows similar immunological abnormalities. In this study, thalidomide was administered in order to understand the mechanism for the improvement in symptoms in BD-like mice. Eight out of ten thalidomide-treated mice showed improvement but none of ten placebo-treated mice (P < 0.005). The improvements were seen in mucocutaneous symptoms. The mice were sacrificed on the 6th day, and the spleens subjected to RT-PCR, FACS, Western blot and immunohistochemical analysis. IL-2, IL-4, IL-6, IL-10, IFN-gamma, TNFalpha, TGFbeta, MCP-1, RANTES, perforin, IP-10, FasL, FasR and MIP-lalpha were determined. Among these, TNFalpha, MIP-1alpha, perforin and Fas were influenced by thalidomide treatment. These results suggest that thalidomide can attenuate HSV-induced BD-like symptoms in mice through the downregulation of TNFalpha (P < 0.005) and the upregulation of MIP-1alpha (P < 0.005), perforin (P < 0.05) and FasR (P < 0.1).

The ultrastructural characteristics of the hair bulb of segmented heterochromia in the scalp hair

Segmented heterochromia is a pigmentary disorder characterized by alternating dark and light segments on each hair shaft. Our aim was to observe the ultrastructure of hair shafts and bulbs to understand the pathogenesis of the disease. Biopsy specimens including normal or diseased hair follicles were prepared for transmission electron microscopy. In dark segments, dense and ellipsoidal melanosomes were noted while small, round ones were found in the light segments. Two groups of melanosomes lined up on the matrix, one of which was composed of compact ellipsoidal melanosomes, and the other was composed of melanosomes with irregular sizes and shapes. Melanocytes seemed to be under necrosis, apoptosis, or dark cell transformation. Langerhans cells were found in the bulb. Two kinds of melanosomes were produced in the same hair bulb simultaneously. Degenerating melanocytes might produce deformed melanosomes. Langerhans cells might be involved in the death of melanocytes. It is unknown how either group of melanosomes is adopted and transferred to the hair cortex producing the characteristic pattern of pigmentation.