Urinary levels of oxidative DNA and RNA damage among workers exposed to polycyclic aromatic hydrocarbons in silicon production: Comparison with 1‐hydroxypyrene

Polycyclic aromatic hydrocarbons (PAH) are ubiquitous occupational and environmental pollutants and the urinary excretion of 1‐hydroxypyrene (1‐OHP) is classically measured for the determination of PAH exposure internal dose. Some of PAH are tumorigenic due to their metabolites ability to generate DNA adducts and oxidative DNA damage through the production of reactive oxygen species during metabolism. 8‐hydroxy‐7,8‐dihydro‐2′‐deoxyguanosine (8‐OHdGuo) is one of the major oxidative DNA lesions and its use as a potential biomarker of genotoxic PAH occupational exposure should be evaluated. Indeed conflicting results are frequently reported in occupational studies in terms of correlation between 8‐OHdGuo urinary levels and PAH exposure. The aim of our study was therefore to determine the potential for PAH occupational exposure to increase urinary oxidative DNA damage. The population consisted of 68 male workers employed in silicon production. The urinary concentrations of 8‐OHdGuo and its homologue in RNA, 8‐hydroxy‐7,8‐dihydroguanosine (8‐OHGuo) were determined using high performance liquid chromatography (HPLC) coupled to tandem mass spectrometry, whereas those of 1‐OHP were measured using HPLC with fluorescence detection. Individual variation rates were calculated on a working day and a working week. The results indicated that, while 1‐OHP levels strongly increased on a working day and even more on a working week, 8‐OHdGuo and 8‐OHGuo urinary levels did not show similar significant increases. Moreover, no correlation between 1‐OHP and oxidative DNA and RNA lesions was found. Consequently, urinary 8‐OHdGuo and 8‐OHGuo did not seem to be relevant biomarkers of genotoxic PAH exposure in the case of the silicon plant studied. Environ. Mol. Mutagen., 2009. © 2008 Wiley‐Liss, Inc.     

Prognostic impact of 8‐hydroxy‐deoxyguanosine and its repair enzyme 8‐hydroxy‐deoxyguanosine DNA glycosylase in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) has a poor prognosis in the setting of chronic inflammation and fibrosis, both of which promote nuclear DNA oxidative damage. 8‐hydroxy‐deoxyguanosine (8‐OHdG) DNA glycosylase (OGG1) enhances the repair of 8‐OHdG, which is the primary oxidative stress‐induced mutation that leads to malignant alterations. This study aims to clarify the relationships between oxidative stress‐induced factors and HCC progression. The clinicopathological factors were compared with immunohistochemistry OGG1 and 8‐OHdG expressions in 86 resected HCC specimens. High 8‐OHdG expression was associated with high serum aspartate transaminase and total bilirubin levels, as well as a low platelet count, compared with low 8‐OHdG expression. Histological liver cirrhosis and poor differentiation were more frequent in patients with high 8‐OHdG expression than in those with low 8‐OHdG expression. The 8‐OHdG was negatively correlated with OGG1 expression in HCC patients. Therefore, we classified the patients into two groups, low OGG1/high 8‐OHdG group and the other group. The patients with low OGG1/high 8‐OHdG expressions had worse prognosis than those with the other expressions. Our results showed that low OGG1/high 8‐OHdG expressions in nuclei influence HCC patient outcomes. Evaluating the patterns of OGG1 and 8‐OHdG expressions might provide pivotal prognostic biomarkers in patients with HCC.     

Sources of polycyclic aromatic hydrocarbon exposure in non-occupationally exposed Koreans

Urinary 1-hydroxypyrene (1-OHP), an exposure biomarker for polycyclic aromatic hydrocarbons (PAHs), was used to identify potential sources of PAH exposure for 660 Koreans who were not occupationally exposed to PAHs (65% male; 35% female; mean age, 36.5 +/- 11.1 years). In this study, 74% of subjects had detectable levels of urinary 1-OHP, with a concentration range of 0.001-3.796 microg/L (median, 0.079 microg/L). A backward elimination was conducted: five variables were selected with a significance level for removal of P < or = 0.1. The results of this study showed that residence in areas with relatively poor environmental conditions (Seoul and Suwon) was strongly associated with high concentrations of urinary 1-OHP (P = 0.007), while consumption of fried chicken and length of time spent outdoors had marginal positive associations with urinary 1-OHP levels (P = 0.06 and P = 0.09, respectively). Compared with the above three factors, tobacco smoking and urinary cotinine levels were poorly associated with urinary 1-OHP (P = 0.16 and 0.23, respectively). Pear consumption had an inverse association with urinary 1-OHP levels (P < 0.01). Individual variations in urinary 1-OHP concentrations were evaluated by considering the subjects' age, sex, and genetic polymorphisms in enzymes involved in the metabolism of PAHs. Among the individual variations, GSTT1-present subjects showed higher 1-OHP levels than GSTT1-absent subjects in cities having 10-microm particulate matter (PM(10)) levels and population density lower than those of Seoul and Suwon (P < 0.05). These epidemiological results suggest that the above factors that should be considered in preventing PAH exposure.     

Radiation exposure differentially affects songbird 8-hydroxy-2'-deoxyguanosine plasma profiles: ionizing radiation damage response in songbirds

The importance of understanding the effects of radiation exposure on wildlife is a critical responsibility of our stewardship of nuclear energy production. We tested the hypothesis that songbirds respond to exogenous radiation exposure with changes in plasma 8-hydroxy-2'-deoxyguanosine (8-OH-dG). We exposed two species of songbirds, house sparrows (Passer domesticus; n = 12) and song sparrows (Melospiza melodia; n = 12), to one of four acute whole-body radiation treatments: 75, 150, 300, or 600 mGy. We measured DNA damage by proxy as 8-OH-dG levels in the plasma at 0 hr (baseline), 36 hr, and 7 days post radiation. For both species, at all radiation treatments, 8-OH-dG levels increased significantly 36 hr following radiation exposure. However, songbird species differed significantly in response to treatment across time and between treatment groups. Song sparrows showed no significant changes in 8-OH-dG levels between 36 hr and Day 7. In contrast, house sparrows exposed to 300 and 600 mGy had significantly increased 8-OH-dG levels at Day 7 compared with 36 hr. This study demonstrates that in a controlled experiment, in isolation from other sources of genotoxicity, radiation exposure significantly affects songbirds. Our results suggest future research examining the effects of radiation on songbirds must consider using multiple species to assess the biological effects of radiation, as different species can show strikingly different responses to radiation dosage across time.     

Coexposure to benzo[a]pyrene and UVA induces DNA damage: first proof of double-strand breaks in a cell-free system

DNA damage induced by solar ultraviolet (UV) radiation plays an important role in the induction of skin cancer. Although UVA constitutes the majority of solar UV radiation, it is less damaging to DNA than UVB. The DNA damage produced by UVA radiation, however, can be augmented in the presence of a photosensitizer. We previously used benzo[a]pyrene (BaP), an environmental carcinogenic polycyclic aromatic hydrocarbon, as an exogenous photosensitizer, and demonstrated that combined exposure to BaP and UVA resulted in DNA double-strand breaks (DSBs) in cultured Chinese hamster ovary (CHO-K1) cells. In this study, we investigated whether coexposure to BaP and UVA induces DSBs in a cell-free system and whether reactive oxygen species (ROS) were involved in the generation of the DSBs. DSBs were induced by the coexposure both in the cell-free system (in vitro) and in CHO-K1 cells (in vivo), but not by treatment with BaP or UVA alone. DSB induction in vitro required higher doses of UVA and BaP than were required in vivo, suggesting that the mechanism of DSB induction differed. A similar difference in efficiency also was observed in the formation of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) by coexposure to BaP and UVA in vitro and in vivo. A singlet oxygen ((1)O2) scavenger (NaN3) effectively inhibited the production of DSBs and 8-oxodG, suggesting that (1)O2 is a principal ROS generated by BaP and UVA both in vitro and in vivo. Furthermore, repair-deficient xrs-5 cells were more sensitive to coexposure with BaP and UVA than were CHO-K1 cells, but the two cell lines were equally sensitive to the combined treatment in the presence of NaN3. This result suggested that the cell death produced by coexposure to BaP and UVA was at least partly due to the DSBs generated by (1)O2. Our findings indicate that coexposure to BaP and UVA effectively induced DNA damage, especially DSBs, which results in phototoxicity and possibly photocarcinogenesis.     

Total antioxidant status and 8-hydroxy-2′-deoxyguanosine levels in gingival and peripheral blood of periodontitis patients

Introduction: The aim of this study was to determine 8-OHdG concentration as a biomarker of oxidant-induced DNA damage and to assess total antioxidant status (TAS) in gingival and peripheral blood during periodontal lesion. Materials and Methods: The study included 56 untreated periodontitis patients (26 with aggressive periodontitis, and 30 with chronic periodontitis (CP). The control group consisted of 25 healthy volunteers without pathological changes in the periodontium. Competitive ELISA was used to measure 8-OHdG. A colorimetric method based on the reduction of ABTS^o+ radical cation generation was used to measure TAS. Results: Significantly higher 8-OHdG concentrations were detected in the gingival blood in both groups of patients with periodontitis than in the control group. Subjects with CP had significantly decreased TAS levels in the gingival blood compared with the control group. A significantly decreased TAS level in the peripheral blood in both patient groups compared with the control group was found. Significant positive correlation between TAS levels in venous and gingival blood in all the periodontitis patients and in the CP group was observed. Conclusions: The oxidative burst in periodontitis may lead to significant local damage to nucleic acids. The significantly decreased TAS level in the gingival blood of CP patients compared with the healthy subjects suggests the possibility of a significant decrease in local antioxidant system capacity during the course of periodontitis. The decreased TAS level in the peripheral blood in the group of all patients with periodontitis may be one of the pathogenic mechanisms underlying the links between periodontal disease and several systemic diseases for which periodontitis is regarded as a independent risk factor.     

Women are more susceptible than men to oxidative stress and chromosome damage caused by polycyclic aromatic hydrocarbons exposure

Exposure to environmental polycyclic aromatic hydrocarbons (PAHs) has been associated with increased risk of cancer, but evidence for gender differences in this association is limited. The aim of this study was to examine the gender differences in PAHs caused early genotoxic effects such as oxidative stress and chromosome damage, which are potential carcinogenic etiology of PAHs. A total of 478 nonsmoking workers (272 men and 206 women) from a coke oven plant were recruited. We determined 16 environmental PAHs in their workplaces, and measured concentrations of 12 urinary PAH metabolites (OH‐PAHs), plasma benzo[a]pyrene‐r‐7,t‐8,t‐9,c‐10‐tetrahydotetrol‐albumin (BPDE‐Alb) adducts, urinary 8‐hydroxydeoxyguanosine (8‐OHdG) and 8‐iso‐prostaglandin‐F2α (8‐iso‐PGF2α), and micronucleus frequencies in lymphocytes in all subjects. It showed that, women working at the office, adjacent to the coke oven, and on the bottom or side of the coke oven displayed significantly higher levels of urinary 8‐OHdG and 8‐iso‐PGF2α, and lymphocytic micronucleus frequencies compared with men working at above areas, respectively (all P < 0.05). These gender differences remain significant after adjusted for potential confounders and urinary ΣOH‐PAHs or plasma BPDE‐Alb adducts. A significant interaction existed between gender and BPDE‐Alb adducts on increasing micronucleus frequencies (P_interaction < 0.001). We further stratified all workers by the tertiles of urinary ΣOH‐PAHs or plasma BPDE‐Alb adducts, and the above gender differences were more evident in the median‐ and high‐exposure groups (all P < 0.05). In conclusion, women were more susceptible than men to oxidative stress and chromosome damage induced by PAHs, which may add potential evidence underlying gender differences in PAH exposure‐related lung cacinogenesis. Environ. Mol. Mutagen. 55:472–481, 2014. © 2014 Wiley Periodicals, Inc.     

Genotoxicity and physicochemical characteristics of traffic-related ambient particulate matter

Exposure to ambient particulate matter (PM) has been linked to several adverse health effects. Since vehicular traffic is a PM source of growing importance, we sampled total suspended particulate (TSP), PM(10), and PM(2.5) at six urban locations with pronounced differences in traffic intensity. The mutagenicity, DNA-adduct formation, and induction of oxidative DNA damage by the samples were studied as genotoxicological parameters, in relation to polycyclic aromatic hydrocarbon (PAH) levels, elemental composition, and radical-generating capacity (RGC) as chemical characteristics. We found pronounced differences in the genotoxicity and chemical characteristics of PM from the various locations, although we could not establish a correlation between traffic intensity and any of these characteristics for any of the PM size fractions. Therefore, the differences between locations may be due to local sources of PM, other than traffic. The concentration of total (carcinogenic) PAHs correlated positively with RGC, direct and S9-mediated mutagenicity, as well as the induction of DNA adducts and oxidative DNA damage. The interaction between total PAHs and transition metals correlated positively with DNA-adduct formation, particularly from the PM(2.5) fraction. RGC was not associated with one specific PM size fraction, but mutagenicity and DNA reactivity after metabolic activation were relatively high in PM(10) and PM(2.5), when compared with TSP. We conclude that the toxicological characteristics of urban PM samples show pronounced differences, even when PM concentrations at the sample sites are comparable. This implies that emission reduction strategies that take chemical and toxicological characteristics of PM into account may be useful for reducing the health risks associated with PM exposure.     

Urinary excretion of prostaglandin F2α and 6-keto-prostaglandin F1α during volume expansion in man

Renal function and the urinary excretion of immunoreactive prostaglandin F_2α (PGF_2α) and 6-keto-prostaglandin F_1α (6-keto-PGF_1α) were investigated during volume expansion (VE) in 9 healthy young adults. The studies were started after at least 17 h of food and fluid deprivation. Volume expansion (3% of body weight) was achieved by a continuous infusion of Ringer's solution (0.22 ml/kg/min). This increased the urinary excretion of sodium from 195±25 to 714±55 μmol/min/1.73 m²(mean ± S.E.) and decreased the excretion of potassium by 24% and plasma renin activity by 60% (P<0.01). The clearance of inulin increased slightly (from 102.4±3.7 to 114.5±6.2 ml/min/1.73 m², P<0.025), whüe clearance of PAH did not change. The excretion of immunoreactive PGF_2α decreased in 8 out of 9 individuals during VE, from 1.58±0.15 to 0.97±0.10 ng/min/1.73 m²(P<0.01). In contrast, excretion of immunoreactive 6-keto-PGF_1α increased in 8 out of 9 subjects, from 2.32±0.20 to 3.47±0.48 ng/min/1.73 m²(P<0.05). Urinary excretion of PGF_2α and 6-keto-PGF_1α may reflect renal synthesis of prostaglandins (PGs) and prostacyclin (PGI₂), respectively. The results indicate that synthesis of PGs is decreased and that of PGI₂ is increased during VE in man. However, no simple relationship could be found between the prostaglandins and the renal functional parameters.     

8-羟基-2-(二丙基氨基)四氢萘干预弥漫性轴索损伤模型大鼠低氧诱导因子1α的表达

文题释义： 8-羟基-2-(二丙基氨基)四氢萘(8-hydroxy-2-(di-n-propylamino)tetralin,8-OH-DPAT)：是五羟色胺1A (5-HTlA)受体激动剂的一种,长久以来一直做为抗精神类药物被广泛研究,其在减轻焦虑和抑郁症的治疗作用的机制已经有据可查,除此以外,5-HTlA受体激动剂仍具有降低体温及神经保护作用。 脑弥漫性轴索损伤(diffuse axonal injury,DAI)：是头部遭受加速性旋转外力作用时,因剪应力造成的以脑内神经轴索肿胀断裂为主要特征的损伤。一般认为,当头部加速运动时,脑组织因受瞬时产生的剪力和张力作用而发生应变,使神经轴索、毛细血管和小血管损伤。弥漫性轴索损伤好发于神经轴索聚集区,如胼胝体、脑干头端背外侧、大脑半球的灰质和白质交界处、小脑、内囊、基底节核团附近及透明隔等处。 背景：8-羟基-2-(二丙基氨基)四氢萘(8-hydroxy-2-(di-n-propylamino)tetralin,8-OH-DPAT)具有降低脑温的作用,且此作用可能是其发挥神经保护作用的潜在机制之一。 目的：观察8-OH-DPAT对弥漫性轴索损伤大鼠脑组织低氧诱导因子1α表达的影响,探讨8-OH-DPAT对弥漫性轴索损伤大鼠神经保护作用的途径。 方法：实验方案经北部战区动物实验伦理委员会批准。将Wistar大鼠随机分为4组：模型组(n=35)、恒温组(n=35)、8-OH-DPAT组(n=35)和正常组(n=7)。除正常组外,其他各组均参照Marmarou法制作弥漫性轴索损伤模型,恒温组和8-OH-DPAT组建模成功后腹腔注射8-OH-DPAT,模型组和正常组腹腔注射生理盐水;恒温组用恒温毯维持体温(37.0±0.5) ℃。每隔1 h测量大鼠脑温。分别于弥漫性轴索损伤后6,12,24,72, 168 h观察大鼠脑组织的损伤程度以及血清和损伤脑组织中低氧诱导因子1α的表达。 结果与结论：①造模后1 h,与恒温组和模型组比较,8-OH-DPAT组大鼠脑温明显下降(P < 0.05),至造模后2 h降至最低(P < 0.05),之后缓慢上升;②苏木精-伊红染色显示,模型组大鼠脑组织损伤最为严重,恒温组次之,8-OH-DPAT组损伤最轻;③免疫组织化学和ELISA结果显示,正常组血清及脑组织低氧诱导因子1α表达很低;弥漫性轴索损伤后6 h,模型组血清及脑组织低氧诱导因子1α表达增多,24 h达高峰,之后逐渐减少;与模型组比较,恒温组和8-OH-DPAT组对应时间点血清及脑组织低氧诱导因子1α表达明显减少(P < 0.05或P < 0.01),8-OH-DPAT组减少更明显(P < 0.01);④结果说明,8-OH-DPAT对弥漫性轴索损伤大鼠脑组织的神经保护作用与其降低大鼠脑温,减少损伤脑组织低氧诱导因子1α的表达有关。 ORCID: 0000-0002-4637-3553(毛振立) 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

Metabolic activation of diesel exhaust carcinogens in primary and immortalized human TP53 knock‐in (Hupki) mouse embryo fibroblasts

Approximately 50% of human tumors have a mutation in TP53. The pattern and spectra of TP53 mutations often differ between cancer types, perhaps due to different etiological factors. The Hupki (human TP53 knock‐in) mouse embryo fibroblast (HUF) immortalization assay is useful for studying mutagenesis in the human TP53 gene by environmental carcinogens. Prior to initiating an immortalization assay, carcinogen treatment conditions must be optimized, which can require a large number of cells. As primary HUF cultures senesce within 2 weeks, restricting their use, we investigated whether immortalized HUFs retaining wild‐type TP53 can be surrogates for primary HUFs in initial treatment optimization. DNA damage by eight compounds found in diesel exhaust, benzo[a]pyrene, 3‐nitrobenzanthrone, 1‐nitropyrene, 1,3‐dinitropyrene, 1,6‐dinitropyrene, 1,8‐dinitropyrene, 6‐nitrochrysene, and 3‐nitrofluorene, was assessed by ³²P‐postlabeling and the alkaline comet assay in primary HUFs and in an immortal HUF cell line J201. For most compounds, higher levels of DNA adducts accumulated in J201 cells than in primary HUFs. This difference was not reflected in the comet assay or by cell viability changes. Experiments in three additional immortal HUF cell lines (AAI49, U56, and E2‐143) confirmed strong differences in DNA adduct levels compared with primary HUFs. However, these did not correlate with the protein expression of Nqo1 or Nat1/2, or with gene expression of Cyp1a1 or Cyp1b1. Our results show that using immortal HUFs as surrogates for primary HUFs in genotoxicity screening has limitations and that DNA adduct formation is the best measure of genotoxicity of the nitro‐polycyclic aromatic hydrocarbons tested in HUFs. Environ. Mol. Mutagen. 2012. © 2011 Wiley Periodicals, Inc.     

CD8+ T cell responses to human immunodeficiency viruses type 2 (HIV-2) and type 1 (HIV-1) gag proteins are distinguishable by magnitude and breadth but not cellular phenotype

The mechanisms underlying the relatively slow progression of human immunodeficiency virus type 2 (HIV-2) compared with HIV-1 infection are undefined and could be a result of more effective immune responses. We used HIV-2 and HIV-1 IFN-gamma enzyme-linked immunospot assays to evaluate CD8(+) T cell responses in antiretroviral-naive HIV-2- ('HIV-2(+)') and HIV-1-infected ('HIV-1(+)') individuals. Gag-specific responses were detected in the majority of HIV-2(+) and HIV-1(+) subjects. Overlapping gag peptide analysis indicated a significantly greater magnitude and breadth of responses in the HIV-1(+) cohort, and this difference was attributable to low responses in HIV-2(+) subjects with undetectable viral load (medians 2107 and 512 spot-forming units per 10(6) PBMC, respectively, p=0.007). We investigated the phenotype of viral epitope-specific CD8(+) T cells identified with HLA-B53- and HLA-B58-peptide tetramers (8 HIV-2(+), 11 HIV-1(+) subjects). HIV-2-specific CD8(+) T cells were predominantly CD27(+) CD45RA(-), and only a minority expressed perforin. The limited breadth and low frequency of CD8(+) T cell responses to HIV-2 gag in aviremic HIV-2(+) subjects suggests that these responses reflect antigen load in plasma, as is the case in HIV-1 infection. Immune control of HIV-2 does not appear to be related to the frequency of perforin-expressing virus-specific CD8(+) T cells.     

Radical Copolymerization of Vinylidene Fluoride with 8‐Bromo‐1H,1H,2H‐perfluorooct‐1‐ene: Microstructure,Crosslinking and Thermal Properties

An original synthesis of 8‐bromo‐1H,1H,2H‐perfluorooct‐1‐ene (BDFO) and its radical copolymerization with vinylidene fluoride (VDF), initiated by 2,5‐bis(tert‐butylperoxy)‐2,5‐dimethylhexane at 134 °C, are presented. The fluorinated bromoalkene was obtained by dehydrobromination of 1,8‐dibromo‐1H,1H,2H,2H‐perfluorooctane in a satisfactory yield. Although BDFO did not homopolymerize under radical initiation, it did copolymerize with VDF. The compositions of the resulting random type copolymers were calculated by means of ¹⁹F NMR spectroscopy and allowed the quantification of the respective amounts of both comonomers in the copolymers, showing good incorporation of the brominated monomer. Nevertheless, obtaining PVDF copolymers containing a high molar percentage of BDFO in good yields was difficult to achieve from initial molar ratios of BDFO higher than 9.2 mol‐%. Radical terpolymerization of VDF, BDFO and hexafluoropropene (HFP) was also successfully achieved. BDFO contents in these co‐ or terpolymers ranged from 3.6 to 12.2 mol‐%. The bromoalkene acted as a cure site monomer and the resulting poly(VDF‐co‐BDFO) copolymers were crosslinked via the bromine atom in the presence of a triallyl isocyanurate/peroxide system. The materials obtained led to more thermally stable copolymers than the uncured ones and their thermostabilities were compared to those of commercially available poly(VDF‐co‐HFP) copolymers crosslinked using diamines.

     

Enhanced major histocompatibility complex class I binding and immune responses through anchor modification of the non-canonical tumour-associated mucin 1-8 peptide

Designing peptide-based vaccines for therapeutic applications in cancer immunotherapy requires detailed knowledge of the interactions between the antigenic peptide and major histocompatibility complex (MHC) in addition to that between the peptide-MHC complex and the T-cell receptor. Past efforts to immunize with high-affinity tumour-associated antigenic peptides have not been very immunogenic, which may be attributed to the lack of T cells to these peptides, having been deleted during thymic development. For this reason, low-to-medium affinity non-canonical peptides represent more suitable candidates. However, in addition to the difficulty in identifying such antigens, peptide binding to MHC, and hence its ability to induce a strong immune response, is limited. Therefore, to enhance binding to MHC and improve immune responses, anchor modifications of non-canonical tumour-associated peptides would be advantageous. In this study, the non-canonical tumour-associated peptide from MUC1, MUC1-8 (SAPDTRPA), was modified at the MHC anchor residues to SAPDFRPL (MUC1-8-5F8L) and showed enhanced binding to H-2Kb and improved immune responses. Furthermore, the crystal structure of MUC1-8-5F8L in complex with H-2Kb was determined and it revealed that binding of the peptide to MHC is similar to that of the canonical peptide OVA8 (SIINFEKL).     

Escherichia coli-induced expression of IL-1 alpha, IL-1 beta, IL-6 and IL-8 in normal human renal tubular epithelial cells

The aim of the present study was to investigate whether the IL-1 family cytokines, in addition to IL-6 and IL-8, could be induced in normal human cortical epithelial cells in response to bacterial stimuli. Human renal tissue was obtained from 9 patients undergoing elective tumour nephrectomy. Renal cortical epithelial cells of tubular origin were prepared from the unaffected tissue. The proximal tubular cells were stimulated for 2, 6 and 24 h with a heat-inactivated pyelonephritogenic Escherichia coli strain DS-17. Cultured unstimulated tubular cells served as controls. IL-1 alpha, IL-1 beta, IL-1 receptor antagonist, IL-6, IL-8, IL-10, TNF-alpha, G-CSF and GM-CSF were analysed using immunohistochemistry at the single cell level. The nonstimulated cells were found to express low levels of IL-6 and IL-8 (mean value < 3% of total cells). In contrast, E. coli exposure resulted in significantly increased incidences of IL-6 and IL-8 expressing cells (mean values approximately 18% of total cells) peaking within two hours of stimulation (P < 0.008 and P < 0.02 versus non-stimulated cells, respectively). A gradual decrease was thereafter observed at 6 and 24 h, respectively, although persistently higher compared to controls. A different kinetic response was found for IL-1 alpha, IL-1 beta and IL-1 receptor antagonist-expressing cells, which peaked 24 h after E. coli stimulation (mean values 3--10%) (P < 0.008, P < 0.02, P < 0.02 versus non-stimulated cells, respectively). Low levels of TNF-alpha and GM-CSF were found in 3 of the 9 donated epithelial cells, peaking at 2 h, and IL-10 and G-CSF producing cells in 1 patient each. In conclusion we found that heat-inactivated pyelonephritic E. coli induced a proinflammatory cytokine response in the normal human proximal tubular cells including the IL-1 family, IL-6 and IL-8.     

Chaperonin containing TCP1, subunit 8 (CCT8) is upregulated in hepatocellular carcinoma and promotes HCC proliferation

The development of molecular pathogenesis of hepatocellular carcinoma (HCC) is complex and involves alterations in the expression and conformation of assorted oncoproteins and tumor suppressors. Chaperonin containing TCP1 (CCT) is a cytolic molecular chaperone complex that is required for the correct folding of numerous proteins. In this study, we investigated a possible involvement of CCT subunit 8 (CCT8) in HCC development. Immunohistochemical analysis was performed in 102 human HCC samples. High CCT8 expression was detected in clinical HCC samples compared with adjacent noncancerous tissues. The univariate and multivariate survival analyses were also performed to determine their prognostic significance. Western blot confirmed the high expression of CCT8 in HCC compared with adjacent normal tissue. Moreover, the biological significance of the aberrant expression of CCT8 was investigated in HCC cell lines. Expression of CCT8 was correlated directly with the histologic grades and tumor size of HCC and high expression of CCT8 was associated with a poor prognosis. CCT8 depletion by siRNA inhibited cell proliferation and blocked S‐phase entry in HuH7 cells. These results suggested that CCT8 might be an oncogene and participate in HCC cell proliferation. These findings provide a potential therapeutic strategy for the treatment of HCC.