Roles of GILZ in protein metabolism of L6 muscle cells exposed to serum from septic rats

Sepsis is a complex inflammatory response to infection, associating with dramatic metabolic disorders. Although the mechanisms of immune response during sepsis have been largely clarified, current studies rarely pay attention to the disordered protein metabolism in sepsis. In this study, L6 rat skeletal muscle cells treated with serum from septic rats were used as an in vitro model for sepsis-like condition in skeletal muscle. We found that the expression of glucocorticoid-induced leucine zipper (GILZ) positively correlates with glucocorticoid receptor and negatively correlates with myosin heavy chain expression in L6 muscle cells upon septic serum induction. Moreover, we propose that GILZ may associate with cytokines such as TNF-α, IL-1β as well as IL-10 to cooperatively modulate the glucocorticoid/glucocorticoid receptor-mediated regulation of protein metabolism during sepsis. So the present study provides a new approach and theoretical basis for further studies on the regulation of protein metabolism of skeletal muscle during sepsis.

[Effects of controllable dynamic inhaled exposure of moxa smoke on LDL-r, ICAM-1 and morphology of heart tissue in rats]

OBJECTIVE

To observe the change of lipid metabolism and vascular endothelium as well as morphology of heart tissue in rats who were long-time exposed to moxa smoke with different concentrations in order to provide reference for safety assessment of moxa smoke on cardiovascular system.

METHODS

One hundred and sixty-eighty Wistar rats were randomly divided into a control group, a low-concentration group, a median-concentration group and a high-concentration group, 42 rats in each one. The rats were exposed to moxa smoke with concentration of 0%, 10%, 40% and 70%, respectively, for 20 min per day. After continuous intervention for six months, enzyme-linked immunosorbent assay (ELISA) was applied to measure the level of low density lipoprotein-receptor (LDL-r) and intercellular adhesion molecule-1 (ICAM-1) in blood serum in each group; the slices of heart tissue were stained with hematoxylin-eosin staining method to observe morphology change of heart tissue.

RESULTS

(1) After the intervention of moxa smoke, the levels of LDL-r and ICAM-1 in the low-concentration group were not statistically different from those in the control group (both P > 0.05); the level of LDL-r in the median-concentration group was significantly increased, which was statistically different from that in the control group [(3.87 +/- 0.27) mg/mL vs (2.12 +/- 0.13) mg/mL, P < 0.01], however, the content of ICAM-1 was not obviously changed; although the level of LDL-r in the high-concentration group was presented with an escalating trend, it was not statistically different from that in the control group (P > 0.05) while the level of ICAM-1 was obviously increased (P < 0.01). (2) Under the light microscope, the abnormalities of cardiac muscle fibers and myocardial cell in each group were not been observed.

CONCLUSION

The long-time intervention of low-concentration moxa smoke has no significant effects on lipid metabolism and vascular endothelium of rats, indicating that clinical application of low-concentration moxa smoke is relatively safe. The long-time intervention of moderate-concentration moxa smoke could significantly increase the clearance rate of cholesterol, implying the beneficial regulation of moxa smoke on lipid metabolism. The high-concentration moxa smoke could induce certain damage to vascular endothelium but its mechanism is in need of further research. The pathologic change of heart tissue could not be induced by moxa smoke with any concentration.

Observation of enhanced monopole strength and clustering in (12)Be

In a recent breakup-reaction experiment using a Be12 beam at 29  MeV/nucleon, the 0+ band head of the expected He4+He8 molecular rotation was clearly identified at about 10.3 MeV, from which a large monopole matrix element of 7.0±1.0  fm2 and a large cluster-decay width were determined for the first time. These findings support the picture of strong clustering in Be12, which has been a subject of intense investigations over the past decade. The results were obtained thanks to a specially arranged detection system around zero degrees, which is essential in determining the newly emphasized monopole strengths to signal the cluster formation in a nucleus.

Focal amplification of the androgen receptor gene in hormone-naive human prostate cancer

BACKGROUND

Androgen receptor (AR)-gene amplification, found in 20-30% of castration-resistant prostate cancer (CRPCa) is proposed to develop as a consequence of hormone-deprivation therapy and be a prime cause of treatment failure. Here we investigate AR-gene amplification in cancers before hormone deprivation therapy.

METHODS

A tissue microarray (TMA) series of 596 hormone-naive prostate cancers (HNPCas) was screened for chromosome X and AR-gene locus-specific copy number alterations using four-colour fluorescence in situ hybridisation.

RESULTS

Both high level gain in chromosome X (≥4 fold; n=4, 0.7%) and locus-specific amplification of the AR-gene (n=6, 1%) were detected at low frequencies in HNPCa TMAs. Fluorescence in situ hybridisation mapping whole sections taken from the original HNPCa specimen blocks demonstrated that AR-gene amplifications exist in small foci of cells (≤ 600 nm, ≤1% of tumour volume). Patients with AR gene-locus-specific copy number gains had poorer prostate cancer-specific survival.

CONCLUSION

Small clonal foci of cancer containing high level gain of the androgen receptor (AR)-gene develop before hormone deprivation therapy. Their small size makes detection by TMA inefficient and suggests a higher prevalence than that reported herein. It is hypothesised that a large proportion of AR-amplified CRPCa could pre-date hormone deprivation therapy and that these patients would potentially benefit from early total androgen ablation.

Serum high-density lipoprotein cholesterol and progression to arterial stiffness in middle-aged and elderly Chinese

BACKGROUND AND AIMS

Low high-density lipoprotein cholesterol (HDL-c) is a risk factor for cardiovascular disease. Brachial-ankle pulse wave velocity (baPWV) is an indicator of arterial stiffness, which is recognized as a predictor of cardiovascular disease. The aim of this study was to investigate the association between HDL-c and baPWV among middle-aged and elderly Chinese.

METHODS

A total number of 1133 Chinese (430 men, 703 women) aged from 50 to 90 years old were recruited from Shanghai downtown district. The baPWV and major cardiovascular risk factors of the participants were measured.

RESULTS

Serum HDL-c was negatively correlated with baPWV (r = -0.143, P < 0.001) after adjustment for age and gender. Multivariate linear regression analysis demonstrated that age (P < 0.001), systolic blood pressure (P < 0.001), HDL-c (P < 0.001), smoking (P = 0.001), BMI (P = 0.002), fasting plasma glucose (P = 0.004), and white blood cell (P = 0.005) were independently associated with baPWV. After multiple adjustments, participants in the highest quartile of HDL-c had an odds ratio of 0.442 (95% CI 0.268-0.729) for developing high arterial stiffness compared with participants in the lowest quartile. The association remained significant after further adjustment for major cardiovascular risk factors.

CONCLUSION

HDL-c has an independent protective effect on arterial stiffness in middle-aged and elderly Chinese. Early detection of HDL-c level is important in high risk populations with arterial stiffness. Increasing HDL-c level may be an attractive therapeutic target for the prevention of arterial function and subsequent disease.

Genotyping of clinical Mycobacterium tuberculosis isolates based on eight loci of MIRU-VNTR

Genotyping that differentiates between strains of Mycobacterium tuberculosis based on variations in the genome of the organism is a useful tool for molecular epidemiological studies of tuberculosis. In the present study, we identified a combination of five mycobacterial interspersed repetitive unit (MIRU) loci and three variable numbers of tandem repeats (VNTR) loci of M. tuberculosis that showed a discriminatory power comparable to that of the 15 to 24 loci-based typing proposed for international standardisation in analysing 210 paediatric isolates obtained from Chongqing, China.

Prognostic value of PTEN loss in men with conservatively managed localised prostate cancer

Background:

The natural history of prostate cancer is highly variable and difficult to predict. We report on the prognostic value of phosphatase and tensin homologue (PTEN) loss in a cohort of 675 men with conservatively managed prostate cancer diagnosed by transurethral resection of the prostate.

Methods:

The PTEN status was assayed by immunohistochemistry (PTEN IHC) and fluorescent in situ hybridisation (PTEN FISH). The primary end point was death from prostate cancer.

Results:

The PTEN IHC loss was observed in 18% cases. This was significantly associated with prostate cancer death in univariate analysis (hazard ratio (HR)=3.51; 95% CI 2.60–4.73; P=3.1 × 10⁻¹⁴). It was highly predictive of prostate cancer death in the 50% of patients with a low risk score based on Gleason score, PSA, Ki-67 and extent of disease (HR=7.4; 95% CI 2.2–24.6; P=0.012) ), but had no prognostic value in the higher risk patients. The PTEN FISH loss was only weakly associated with PTEN IHC loss (κ=0.5). Both PTEN FISH loss and amplification were univariately predictive of death from prostate cancer, but this was not maintained in the multivariate analyses.

Conclusion:

In low-risk patients, PTEN IHC loss adds prognostic value to Gleason score, PSA, Ki-67 and extent of disease.

Zinc-finger protein 331 expression is regulated by promoter region hypermethylation in hepatocellular carcinoma

AIM: To analyze the methylation status and the expression regulation of zinc-finger protein 331 (ZNF331) in hepatocellular carcinoma.

METHODS: Five human hepatic cancer cell lines and 50 specimens of human primary hepatic cancer were employed to detect ZNF331 promoter region methylation by methylation specific PCR (MSP). Semi-quantitative RT-PCR was used to examine the expression of ZNF331.

RESULTS: Partial methylation was found in HBXF344, PLC/PRF/5, HepG2 and BEL-7402 cell lines. Methylation was not detected in SNU449 cell line. Weak expression of ZNF331 was found in HBXF344, PLC/PRF/5, HepG2 and BEL-7402 cell lines. ZNF331 was moderately expressed in SNU449 cell line. Increased expression of ZNF331 was found in HBXF344, HepG2, BEL-7402, and PLC/PRF/5 cell lines after 5-Aza treatment. No significant change was examined in ZNF331 expression in SNU449 cell line before and after 5-Aza treatment. ZNF331 was methylated in 80% (40/50) of primary human hepatic cancer specimens, but methylation was not detectable in normal liver tissue specimens (0/10). No correlation was found between promoter region methylation and gender, age, AFP level, hepatitis virus infection, tumor size or tumor stage.

CONCLUSION: ZNF331 expression is silenced by promoter region hypermethylation in human hepatocellular carcinoma. ZNF331 is frequently methylated in human primary hepatic cancer.

Mir143 expression inversely correlates with nuclear ERK5 immunoreactivity in clinical prostate cancer

Background:

Aberrant mitogen/extracellular signal-regulated kinase 5 (MEK5)–extracellular signal-regulated protein kinase 5 (ERK5)-mediated signalling has been implicated in a number of tumour types including prostate cancer (CaP). The mechanism for ERK5 activation in CaP remains to be fully elucidated. Studies have recently implicated the role of microRNA (miRNA) mir143 expression in the regulation of ERK5 expression.

Methods:

We utilised a tissue microarray (TMA) of 530 CaP cores from 168 individual patients and stained for both mir143 and ERK5. These TMAs were scored by a combination of observer and automated methods.

Results:

We observed a strong inverse relation between ERK5 and mir143, which manifested itself most strongly in the subgroup of 417 cores with non-zero mir143 and ERK5 immunoreactivity, or with only one of mir143 or ERK5 being zero (cc=0.2558 and P<0.0001). Mir143 neither correlate with Gleason scores or prostate-specific antigen levels, nor was it a predictor of disease-specific survival on univariate analysis.

Conclusion:

Although the mechanism for ERK5 activation in CaP remains to be fully elucidated, we have further validated the potential role of mir143 in regulating ERK5 levels in the clinical context. In addition, we demonstrate that the automated counting method for nuclear ERK5 is a clinically useful alterative to observer counting method in patient stratification in the context of ERK5 targeting therapy.

[Effects of long-term intervention of moxa smoke on T lymphocyte subsets and CD4+ CD25+ Treg in peripheral blood of Wistar rats]

OBJECTIVE

To investigate the cellular immune regulation of the long-term intervention of moxa smoke.

METHODS

Thirty-two Wistar rats were randomly divided into a blank group, a low concentration group, a medium concentration group and a high concentration group, 8 cases in each group. In addition to the blank group, rats in the other groups were exposed to the corresponding concentration moxa smoke for 20 min every day, the T lymphocyte subsets and proportion of the CD4+ CD25+ Treg in CD4+ T cells in peripheral blood were tested by flow cytometry after 6 months.

RESULTS

Compared with the blank group, the proportions of CD3+ CD4+, CD3+ CD8+ T cells and CD3+ CD4/CD3+ CD8+ in the other 3 moxa smoke groups were not significantly different (P > 0.05), while the proportions of the CD4+ CD25+ Treg in CD4+ T cells were significantly lower (P < 0.05), but no statistically significant differences among those 3 moxa smoke intervention groups (P > 0.05).

CONCLUSION

Long-term moxa smoke intervention has no significant effect on the proportions of CD3+ CD4+, CD3+ CD8+ T cells and CD3+ CD4+/CD3+ CD8+, but it can decrease the proportions of the CD4+ CD25+ Treg in CD4+ T cells in peripheral blood of rats. The way produced by pretreatment with moxa smoke may play immunomodulatory effect.

Prognostic value of Ki-67 for prostate cancer death in a conservatively managed cohort

Background:

Standard clinical parameters cannot accurately differentiate indolent from aggressive prostate cancer. Our previous work showed that immunohistochemical (IHC) Ki-67 improved prediction of prostate cancer death in a cohort of conservatively treated clinically localised prostate cancers diagnosed by transurethral resection of the prostate (TURP). Here, we present results in a more clinically relevant needle biopsy cohort.

Methods:

Biopsy specimens were microarrayed. The percentage of Ki-67 positively stained malignant cells per core was measured and the maximum score per individual used in analysis of time to death from prostate cancer using a Cox proportional hazards model.

Results:

In univariate analysis (n=293), the hazard ratio (HR) (95% confidence intervals) for dichotomous Ki-67 (⩽10%, >10%) was 3.42 (1.76, 6.62) χ² (1 df)=9.8, P=0.002. In multivariate analysis, Ki-67 added significant predictive information to that provided by Gleason score and prostate-specific antigen (HR=2.78 (1.42, 5.46), χ² (1 df)=7.0, P=0.008).

Conclusion:

The IHC Ki-67 scoring on prostate needle biopsies is practicable and yielded significant prognostic information. It was less informative than in the previous TURP cohort where tumour samples were larger and more comprehensive, but in more contemporary cohorts with larger numbers of biopsies per patient, Ki-67 may prove a more powerful biomarker.

The effect of human antibacterial peptide LL-37 in the pathogenesis of chronic obstructive pulmonary disease

BACKGROUND

Previous research has shown that innate immune system was more important than the acquired immune system in the pathogenesis of COPD. LL-37 is the only human cathelicidin identified so far. As an integral part of the innate immune system, besides antibacterial activity, its chemotactic activity, damage repairing, influencing apoptosis and its cytotoxicity are attracting people's attention. The aim of the present study was to evaluate role of LL-37 in the pathogenesis of COPD.

METHODS

ELISA and immunohistochemistry were applied to investigate the expression of LL-37 in induced sputum and lung tissue of COPD patients. Bronchial epithelial cell (BEP2D) and alveolar epithelial cell (A549) were treated with LL-37 synthesis polypeptide in vitro to assess the role of LL-37 in inflammation and apoptosis.

RESULTS

We found that increased induced sputum levels of LL-37 in COPD patients were associated with airflow limitation, health status and exercise tolerance and the expressing intensity of LL-37 in both airway district and pulmonary alveoli area in COPD group significantly increased compared with control group. Through stimulation by CSE and LPS, the expression of LL-37 was increased in bronchial epithelial cell and alveolar epithelial cell. LL-37 synthesis polypeptide can promote the releasing of inflammatory factor IL-8 and induce apoptosis of bronchial epithelial cell and alveolar epithelial cell.

CONCLUSION

This study suggested that LL-37 may play important role in the pathogenesis of COPD and may be a possible novel therapeutic target in COPD.

Neuroendocrine differentiation does not have independent prognostic value in conservatively treated prostate cancer

In vitro studies have implicated neuroendocrine differentiation in the development of hormone resistant prostate cancer following administration of androgen blockers. Studies on clinical material are equivocal. We wished to understand the significance of neuroendocrine differentiation in our large and well-characterised cohort of clinically localised prostate cancer, treated conservatively. Immunohistochemical expression of chromogranin-A was assessed semi-quantitatively on tissue samples of 806 patients in a tissue microarray approach. The correlation of expression with 10-year prostate cancer survival was examined. Multivariate analysis including contemporary Gleason score was performed and sub-group analysis of early hormone treated patients was also undertaken. Chromogranin-A expression correlated with high Gleason score (χ(2) = 28.35, p < 0.001) and early prostate cancer death (HR = 1.61, 95 %CI = 1.15-2.27, p < 0.001). In univariate analysis, NE differentiation correlated significantly with outcome (HR = 1.61, 95 % CI 1.15-2.27, p < 0.001) However in multivariate analysis including Gleason score, chromogranin-A expression was not an independent predictor of survival (HR = 0.97, 95 %CI = 0.89-1.37, p = 0.87). Although chromogranin-A expression was higher in patients with early hormone therapy (χ(2) = 7.25, p = 0.007), there was no association with prostate cancer survival in this sub-group (p = 0.083). Determination of neuroendocrine differentiation does not appear to have any bearing on the outcome of prostatic carcinoma and does not add to the established prognostic model.

[The toxic effects of lead acetate on the apoptosis and the ultrastructure in human renal tubular epithelial cells (HK-2)]

OBJECTIVE

To explore the toxic effects of lead acetate on the apoptosis and ultrastructure of human renal tubular epithelial cells (HK-2).

METHODS

After HK-2 cells were exposed to 5, 10 and 20 µmol/L lead acetate for 24 h, the morphological changes of HK-2 cells were observed by Hochest 33342-PI staining, and the ultrastructure changes of HK-2 cells were examined under a electron microscope, LDH activity and MDA content in supernatant of HK-2 cellular culture were detected by spectrophotometer, DNA damage of HK-2 was determined by DNA ladder and the apoptotic rates of HK-2 cells were measured by flow cytometry.

RESULTS

The morphological changes of apoptotic HK-2 cells in exposure group were observed by Hochest 33342-PI staining. The cytoplasm vacuoles, karyopycnosis, nuclear membrane vague and apoptotic bodies in HK-2 cells of exposure group were found under electron microscopy. LDH activity and MDA contents in exposure group increased significantly, as compared to control group (P < 0.01). The results of DNA Ladder showed that DNA damage of HK-2 cells in exposure group appeared. The apoptotic rates of HK-2 cells exposed to 5, 10, 20 µmol/L lead acetate were 14.16% ± 2.94%, 19.45% ± 2.73%, 25.01% ± 3.97%, respectively, which were significantly higher than that (5.81% ± 2.18%) in control group (P < 0.05).

CONCLUSION

Lead acetate could remarkably induce the apoptosis of HK-2 cells and affect the kidney.

Inhibition of cyclooxygenase-2 by tetramethylpyrazine and its effects on A549 cell invasion and metastasis

Cyclooxygenase (COX)-2 plays an important role in tumorigenesis and has been implicated to be a critical factor for invasion and metastasis of lung cancer. Tetramethylpyrazine (TMP), an effective component of the traditional Chinese medicine Chuanxiong, has been traditionally used in treating neurovascular and cardiovascular diseases. Recently TMP has been reported to have beneficial effect in cancer patients. However, the function and the mechanism of TMP in lung cancer have not been elucidated to date. In this study, we investigated the in vitro and in vivo effect of TMP in tumorigenesis and whether COX-2 is a molecular target of TMP. We showed that TMP exhibited a dose- and time-dependent inhibition on A549 cell proliferation by suppressing cell cycle progression. In vitro treatment of A549 cells with TMP resulted in a significant inhibition of invasion, associated with reduced activities of COX-2 and MMP-2/TIMP-2. Furthermore, in vivo experiments showed that TMP significantly suppressed metastatic growth of A549 cells and COX-2 expression in metastatic nude mouse model. This preclinical study provides the first evidence for the novel anti-tumor effects of TMP as a COX-2 pathway inhibitor in human adenocarcinoma cell line A549. These studies suggest that TMP may serve as an effective agent for the treatment and chemoprevention of non-small cell lung cancer.

First Report of Neocosmospora striata Causing Peanut Pod Rot in China

In 2008, an outbreak of pod rot of peanut (Arachis hypogaea L.) occurred on most of the peanut cultivars in the Old Yellow River drainage area, the largest peanut-growing region in China. Disease incidence reached as high as 90% in some fields, causing severe yield losses. The black rot of pods and blackened, nonrotting taproots is similar to symptoms of peanut black rot caused by Cylindrocladium parasiticum, but the reddish orange perithecia of C. parasiticum were not found on the taproots close to the surface of the soil. The foliage of affected plants was generally asymptomatic, but some plants turned greener. This pod rot disease was further investigated in 2008 and 2010. Twenty-three Fusarium-like isolates were obtained from symptomatic, surface-disinfested pods with a frequency of 82%. These isolates were fast growing, with flat, thin, and grayish white colonies when cultured on potato dextrose agar (PDA) at 28°C for 3 to 4 days. The hyaline, elongated to cylindrical conidia, aggregated in slimy heads on conidiogenous cells developed from undifferentiated hyphae when observed with the light microscope. The size of conidia (single celled or one septum) varied from 3 to 9 μm long and 1.5 to 3.5 μm wide on the basis of the measurement of 50 spores. Some conidia appeared slightly curved. Ascomata formed within 10 to 14 days, with a punctate appearance on the colony. The cerebriform ascomata were dark brown, pyriform, ostiolate, glabrous, 120 to 170 × 90 to 130 μm, and with necks 30 to 50 μm long. Asci measured 60 to 90 × 6 to 10 μm, were cylindrical to cylindric-clavate, thin walled, and had an apical ring. Ascospore arrangement was obliquely uniseriate or partially biseriate, very pale yellow to hyaline, ellipsoidal, and measured 8 to 12 × 4.5 to 6 μm. Some spores had a median transverse straight or curved septum and were slightly constricted at the septum, with 6 to 10 thin, transverse, hyaline flanges. Morphological characteristics of the isolates with ascomata dark brown and ascospores with 6 to 10 transverse hyaline flanges matched the description for Neocosmospora striata (1). The internal transcribed spacer (ITS) region of rDNA was amplified from extracted template DNA with primer pairs ITS4/ITS5 and sequenced. A 591-bp amplicon (GenBank Accession No. HM461900) had 99% sequence identity with Fusarium solani (HQ607968 and HQ608009) and N. vasinfecta (GU213063), which indicated that these fungi belong to the genus Neocosmospora or Fusarium, although there is no direct sequence evidence that they are N. striata. N. striata has only been previously reported in Japan (2). This species is unique because of the dark brown ascomata and there is no comparable species (1). Koch's postulates were completed by surface-disinfesting 80 peanut pods of cv. Jihua 9813 and soaking them in conidial suspensions (10⁵ conidia/ml) for 2 min. Another 80 other pods soaked in sterile water served as controls. All peanuts were incubated in moist petri dishes under darkness at 28°C. Symptoms similar to those originally observed in the field formed within 10 days on all inoculated peanut pods and not the controls. N. striata was reisolated from all affected peanut pods. To our knowledge, this is first report of N. striata causing peanut pod rot in China and the first description of the anamorph of the fungus. References: (1) P. F. Cannon et al. Trans. Br. Mycol. Soc. 82:673, 1984. (2) S. Udagawa et al. Trans. Mycol. Soc. Jpn. 16:340, 1975.

CD117-positive cells in human hepatocarcinoma cell line HepG2: isolation and evaluation of their stem cell properties

AIM: To isolate CD117⁺ cells from human hepatocarcinoma cell line HepG2 and to observe their biological behavior and stem cell properties.

METHODS: HepG2 cells were cultured in serum-free medium. Flow cytometry was used to detect the expression of CD117 in HepG2 cells and sphere cells. CD117⁺ and CD117^- cells were sorted by FACS and their ability of proliferation and self-renewal was observed in vitro. Chemosensitivity to cisplatin was determined by CCK-8 assay. The inhibitory rate of cells treated with cisplatin, the half maximal inhibitory concentration (IC₅₀) and resistance index (RI) were measured.

RESULTS: HepG2 cells could survive, proliferate and form sphere cells in serum-free medium. The sphere-forming rate was 6.21% ± 2.03%. The percentage of CD117⁺ cells population in sphere cells increased by 9 folds compared to HepG2 cells. The sphere-forming ability and proliferation ability of CD117⁺ subpopulation in serum-free medium were significantly higher than un-sorted cells and CD117^- cells. The inhibitory rate of CD117⁺ cells treated with cisplatin of different concentrations was lower than un-sorted cells and CD117^- cells. The IC₅₀ were 12.229 μmol/L in CD117⁺ cells, 7.970 μmol/L in un-sorted cells, and 7.345 μmol/L in CD117^- cells, and the RI of CD117⁺ cells and un-sorted cells were 1.165 and 1.076, respectively.

CONCLUSION: CD117⁺ cells are a subpopulation of HepG2 cells with stem cell properties. CD117 may be a candidate surface marker for liver cancer stem cells.

Host selection and niche differentiation in sucking lice (Insecta: Anoplura) among small mammals in southwestern China

Understanding factors that shape host selection has been a classic issue in ecology, evolutionary biology, and epidemiological investigation. During the survey from 2000 to 2009, a total of 11,216 individuals of small mammals were captured from Yunnan Province in southwestern China. The captured small mammalian hosts belong to five orders, ten families, 35 genera, and 65 species and from their body surface, 38,885 individuals of ectoparasitic sucking lice were collected, which represent five families, seven genera, and 31 species. Based on niche overlap of dominant sucking lice on their primary hosts, we used hierarchical cluster analysis to sort different sucking louse species' resource utilizations of similar kind into respective categories. Given λ<5, there are only two groups clustered, however, sucking louse species' resource utilization was sorted into eight respective categories at λ=15. The results revealed that most species of sucking lice usually had high host specificity and a certain species of sucking louse usually restricted to one or few small mammalian species as their dominant hosts. Correspondence analysis was used to visualize associations between parasitic sucking lice and their small mammalian hosts, which suggested three different patterns of host resource utilization: species specialists, genera generalists, and multiple selections. For example, Sathrax durus (Johnson) only parasitized on species of Tupaia belangeri (Wagner), Hoplopleura edentula (Fahredholz) predominatly on genus of Eothenomys, and Polyplax reclinata (Nitzsch) on Family of Soricidae. Our results demonstrate that sucking lice have high host specificity and this might be due to coevolution between sucking lice and their hosts.

Variation of human papillomavirus 16 in cervical and lung cancers in Sichuan, China

Although the crucial role of human papillomaviruses (HPVs), especially HPV-16 in various cancers has been confirmed, the variation of HPV-16 among different cancers have not been investigated in a specific geographic location. In order to elucidate whether similar HPV-16 variants are involved in different kinds of cancers in the same geographic location, the analysis of sequence variants of E6 and E7 oncogenes and L1 gene of HPV-16 in cervical and lung cancers in Sichuan, China, was carried out. Tissue samples from 122 cervical cancers, 104 lung cancers, and 138 controls were subjected to RT-PCR or PCR, sequencing, and sequence analysis. The infection rates of HPV-16 in cervical, lung cancers, and non-malignant controls were 68.9%, 17.3%, and 37.0%, respectively. Asian prototype variants prevailed in cervical and lung cancers, while European prototype variants in non-malignant controls. In comparison to the lung cancer, cervical cancer showed a much higher diversity of HPV-16 oncogenes. These results indicate that in Sichuan, China, Asian prototype variants of HPV-16 are more pathogenic than their European counterparts.

Radiosensitization and growth inhibition of cancer cells mediated by an scFv antibody gene against DNA-PKcs in vitro and in vivo

BACKGROUND

Overexpression of DNA-dependent protein kinase catalytic subunit (DNA-PKcs) is commonly occurred in cancers and causes radioresistance and poor prognosis. In present study, the single-chain variable antibody fragments (scFv) targeting DNA-PKcs was developed for the application of radiosensitization in vitro and in vivo. A humanized semisynthetic scFv library and the phage-display antibodies technology were employed to screen DNA-PKcs scFv antibody.

METHODS

DNA-PKcs epitopes were predicted and cloned. A humanized semisynthetic scFv library and the phage-display antibodies technology were employed to screen DNA-PKcs scFv antibody. DNA damage repair was analyzed by comet assay and immunofluorescence detection of gammaH2AX foci. The radiosensitization in vivo was determined on Balb/c athymic mice transplanted tumours of HeLa cells.

RESULTS

Four epitopes of DNA-PKcs have been predicted and expressed as the antigens, and a specific human anti-DNA-PKcs scFv antibody gene, anti-DPK3-scFv, was obtained by screening the phage antibody library using the DNA-PKcs peptide DPK3. The specificity of anti-DPK3-scFv was verified, in vitro. Transfection of HeLa cells with the anti-DPK3-scFv gene resulted in an increased sensitivity to IR, decreased repair capability of DNA double-strand breaks (DSB) detected by comet assay and immunofluorescence detection of gammaH2AX foci. Moreover, the kinase activity of DNA-PKcs was inhibited by anti-DPK3-scFv, which was displayed by the decreased phosphorylation levels of its target Akt/S473 and the autophosphorylation of DNA-PKcs on S2056 induced by radiation. Measurement of the growth and apoptosis rates showed that anti-DPK3-scFv enhanced the sensitivity of tumours transplanted in Balb/c athymic mice to radiation therapy.

CONCLUSION

The antiproliferation and radiosensitizing effects of anti-DPK3-scFv via targeting DNA-PKcs make it very appealing for the development as a novel biological radiosensitizer for cancer therapeutic potential.

Gene expression profile and cytotoxicity of human bronchial epithelial cells exposed to crotonaldehyde

Crotonaldehyde is an environment pollutant and lipid peroxidation product. Crotonaldehyde produces adverse effects to humans and serves as a risk factor for human pulmonary diseases. Like acrolein and 4-hydroxynonenal, crotonaldehyde seems likely to alter many cell signaling cascades, including inflammatory responses. The purpose of this study was to investigate the genome-wide transcriptional responses of normal human bronchial epithelial cells exposed to crotonaldehyde. Using microarrays technology, the global changes in transcriptional level were analyzed. Prior to RNA extraction, cells were exposed to crotonaldehyde at 40 or 80 microM for 3 or 6h. Real-time quantitative polymerase chain reaction (qPCR) was performed to validate microarray data and cell cycle arrest was determined. The commonly differentially regulated genes in many biological processes were dysregulated including inflammatory responses, exogenous metabolism, cell cycle, heat shock responses, and antioxidant responses. Results in the present study screen out the important roles of HMOX1 in regulating other signaling cascades and ALDH1A3 in detoxifying exogenous toxicants. Collectively, our study demonstrated that crotonaldehyde altered gene expression profile in the genome-wide transcriptional level in normal human bronchial epithelial cells. And many of them represented potential mechanisms of crotonaldehyde causing cytotoxicity and tissue injury in the human lung.

[Key genes in the pathogenesis of prostate cancer in Chinese men: a bioinformatic study]

OBJECTIVE

The purpose of this study was to construct a pathway-based network using differentially expressed genes in prostate cancer (PCa) screened by cDNA microarray chips in domestic research to visualize the relations among the genes obtained from the microarray data, and identify the genes with significant influence on this network by statistical analysis. It also aimed to search for the genes that play key roles in the tumorigenesis of PCa, and probe into the molecular mechanism of PCa pathogenesis in Chinese men.

METHODS

The relevant domestic literature of recent years were reviewed to sum up differentially expressed genes in PCa according to the screened microarray data. The OMIM database was used to analyze the relations among these genes and build a network of biological pathway. Furthermore, a statistical method, namely node contraction, was employed to compare the importance of the key genes.

RESULTS

According to the gene expression profiling data, there were 113 differentially expressed genes, 51 up-regulated and 62 down-regulated. A pathway-based network including 68 inter-related genes was constructed using the OMIM database. The importance of every key node was calculated using the method of node contraction, and 12 key genes were identified, incuding c-MYC, VEGF, HSPCA, TGFbeta1, RANTES, EGR1, etc, which probably played important roles in the pathogenesis and progression of prostate cancer.

CONCLUSION

We applied bioinformatics to the analysis of the gene expression profiling data in China, constructed a network of the differentially expressed genes using the OMIM database and method of node contraction, appraised the importance of the key genes, and established a method for the overall analysis of the gene chip data, which have paved a new ground for further researches on the pathogenesis of prostate cancer in Chinese men.

Alteration of transcriptional profile in human bronchial epithelial cells induced by cigarette smoke condensate

Despite the significance of cigarette smoke for carcinogenesis, the molecular mechanisms that lead to increased susceptibility of human cancers are not well-understood. In our present study, the oncogenic transforming effects of cigarette smoke condensate (CSC) were examined using papillomavirus-immortalized human bronchial epithelial cells (BEP2D). Growth kinetics, saturation density, resistance to serum-induced terminal differentiation, anchorage-independent growth and tumorigenicity in nude mice were used to investigate the various stages of transformation in BEP2D cells. Illumina microarray platforms were used to explore the CSC-induced alteration of global mRNA expression profiles of the earlier period and the advanced stage of CSC-treated BEP2D cells. We showed here that a series of sequential steps arose among CSC-treated immortalized human bronchial epithelial cells, including altered growth kinetics, resistance to serum-induced terminal differentiation, and anchorage-independence growth. In the earlier period of CSC treatment, 265 genes were down-regulated and 63 genes were up-regulated, respectively, and in the advanced stage of CSC treatment, 313 genes were down-regulated and 145 genes were up-regulated, respectively. Notably, among those genes, the expression of some of imprinted genes such as IGF2, NDN, H19 and MEG3 were all silenced or down-regulated in CSC-treated cells. These genes reactivated after 5 microM 5-aza-2-deoxycytidine (5-aza-dC) treatment. These results demonstrated that long-term treatment of human bronchial epithelial cells with CSC may adversely affect their genetic and epigenetic integrity and lead to further transformation.

Secreted LOXL2 is a novel therapeutic target that promotes gastric cancer metastasis via the Src/FAK pathway

The purpose of this study was to investigate invasion- and metastasis-related genes in gastric cancer. To this end, we used the transwell system to select a highly invasive subcell line from minimally invasive parent cells and compared gene expression in paired cell lines with high- and low-invasive potentials. Lysyl oxidase-like 2 (LOXL2) was overexpressed in the highly invasive subcell line. Immunohistochemical analysis revealed that LOXL2 expression was markedly increased in carcinoma relative to normal epithelia, and this overexpression in primary tumor was significantly associated with depth of tumor invasion, lymph node metastasis and poorer overall survival. Moreover, LOXL2 expression was further increased in lymph node metastases compared with primary cancer tissues. RNA interference-mediated knockdown and ectopic expression of LOXL2 showed that LOXL2 promoted tumor cell invasion in vitro and increased gastric carcinoma metastasis in vivo. Subsequent mechanistic studies showed that LOXL2 could activate both the Snail/E-cadherin and Src kinase/Focal adhesion kinase (Src/FAK) pathways. However, secreted LOXL2 induced gastric tumor cell invasion and metastasis exclusively via the Src/FAK pathway. Expression correlation analysis in gastric carcinoma tissues also revealed that LOXL2 promoted invasion via the Src/FAK pathway but not the Snail/E-cadherin pathway. We then evaluated secreted LOXL2 as a target for gastric carcinoma treatment and found that an antibody against LOXL2 significantly inhibited tumor growth and metastasis. Overall, our data revealed that LOXL2 overexpression, a frequent event in gastric carcinoma progression, contributes to tumor cell invasion and metastasis, and LOXL2 may be a therapeutic target for preventing and treating metastases.