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Abstract Background Legionella pneumophila is the causative agent of human Legionnaire's disease. During infection, the bacterium invades macrophages and lung epithelial cells, and replicates intracellularly. However, little is known about its interaction with T cells. We investigated the ability of L. pneumophila to infect and stimulate the production of interleukin-8 (IL-8) in T cells. The objective of this study was to assess whether L. pneumophila interferes with the immune system by interacting and infecting T cells. Results Wild-type L. pneumophila and flagellin-deficient Legionella, but not L. pneumophila lacking a functional type IV secretion system Dot/Icm, replicated in T cells. On the other hand, wild-type L. pneumophila and Dot/Icm-deficient Legionella, but not flagellin-deficient Legionella or heat-killed Legionella induced IL-8 expression. L. pneumophila activated an IL-8 promoter through the NF-κB and AP-1 binding regions. Wild-type L. pneumophila but not flagellin-deficient Legionella activated NF-κB, p38 mitogen-activated protein kinase (MAPK), Jun N-terminal kinase (JNK), and transforming growth factor β-associated kinase 1 (TAK1). Transfection of dominant negative mutants of IκBα, IκB kinase, NF-κB-inducing kinase, TAK1, MyD88, and p38 MAPK inhibited L. pneumophila-induced IL-8 activation. Inhibitors of NF-κB, p38 MAPK, and JNK blocked L. pneumophila-induced IL-8 expression. In addition, c-Jun, JunD, cyclic AMP response element binding protein, and activating transcription factor 1, which are substrates of p38 MAPK and JNK, bound to the AP-1 site of the IL-8 promoter. Conclusions Taken together, L. pneumophila induced a flagellin-dependent activation of TAK1, p38 MAPK, and JNK, as well as NF-κB and AP-1, which resulted in IL-8 production in human T cells, presumably contributing to the immune response in Legionnaire's disease.

Background: Cervical cancer is the most common cancer in women living in Vientiane, Lao People's Democratic Republic (PDR). This study examines cervical cytology using a liquid-based cytology (LBC) method and reports the presence of high-risk (HR) human papillomavirus (HPV).Methods: We collected cervical samples from 1475 asymptomatic and healthy volunteers from six hospitals in Lao PDR. A total of 1422 volunteers (mean age 39.1 ± 6.4 years, range 30-54 years) were included in the final analysis. We performed HPV typing using the polymerase chain reaction technique to detect HR-HPV samples with abnormal cytology.Results: The overall rates of abnormal cytology and HR-HPV-positive in the samples were 9.3% (132/1422) and 47.7% (63/132), respectively. The samples with abnormal cytology included 13 high-grade squamous intraepithelial lesions and one squamous cell carcinoma case. The results showed that the most common type of HPV was HPV16 (20.5%) followed by HPV58 (9.1%).Conclusions: Healthy women in Vientiane, the capital of Lao PDR, have high rates of abnormal cervical cytology and are likely to be HR-HPV-positive. A system for detection and prevention of cervical cancer in these women should be developed in the near future. [ABSTRACT FROM AUTHOR]

Introduction: Although positron emission tomography (PET) with 2-deoxy-2-[fluorine-18]fluoro-d-glucose integrated with computed tomography (CT), ( 18 F-FDG PET/CT), has recently improved the mediastinal nodal staging of non-small cell lung cancer (NSCLC), this method can show false negativity. We immunohistochemically investigated the expression of glucose transporters (GLUT-1, SGLT-1, and SGLT-2) in false negative and true positive mediastinal nodes via 18 F-FDG PET/CT., Methods: We investigated patients with clinically-diagnosed N0/pathological N2 diseases and patients with clinically-diagnosed N2/pathological N2 disease. The patients who were included in this study were evaluated using 18 F-FDG PET/CT followed by surgical resection between January 2004 and December 2015. The expression of GLUT-1, SGLT-1, and SGLT-2 in the metastatic mediastinal lymph nodes, and clinicopathological variables such as primary tumor size, lymph node size, histological type, and SUV max of the primary lesion, were compared between false negative nodes and true positive nodes., Results: The total number of PET false negative metastatic mediastinal lymph nodes was 22 in the 17 patients who were clinical N0/pathological N2, and the number of PET true positives was 15 in the 11 patients who were clinical N2/pathological N2. GLUT-1 expression was positive in five false negative nodes and 10 true positive nodes. SGLT-2 expression was positive in 12 false negative nodes and one true positive node, whereas both false negative and true positive nodes showed no SGLT-1 staining. Univariate analysis showed that the reduced expression of GLUT-1 (P = 0.015), and overexpression of SGLT-2 (P = 0.004) were the significant causative factors for false negative nodes. Multivariate analysis also showed that the reduced expression of GLUT-1 (P = 0.012) and overexpression of SGLT-2 (P = 0.006) were the significant causative factors for false negative nodes., Conclusion: It suggests that the reduced expression of GLUT-1 and overexpression of SGLT-2 are associated with false-negative lymph node metastases in NSCLC., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Aberrant crypt foci (ACF) and mucin-depleted foci (MDF) have recently been recognized as pre-neoplastic lesions in the colon of carcinogen-treated rodents. In the present study, we analyzed the sequential development of ACF and MDF histopathologically in the colon of rats from 5 to 40 weeks after DMH treatment. The numbers of ACF per colon increased over time during the experiment, and were much higher than the number in tumors, while the number of MDF per colon remained unchanged from the early stage (the 5th week after carcinogen exposure), and approximate to those in tumors. The incidence of ACF, which was much higher than that of tumors, also increased gradually in a time-dependent manner. The incidence of MDF, however, was similar to that of tumors and did not change significantly during the whole experiment. No lesion as dysplasia with high-grade (DHG) or adenocarcinoma (AC) were found in any large ACF from the 5th to 40th week histopathologically, whereas all of the large MDF showed DHG or AC features. Even at 5 weeks, MDF showed features of DHG. We classified these into two forms of MDF: flat and protruded MDF. At 40 weeks, the number of flat MDF per colon decreased significantly compared with that at 20 weeks (p<0.05), however, the number of protruded MDF per colon increased (p<0.01), and the percentage of DHG in a protruded MDF lesion decreased but that of AC increased remarkably. In conclusion, MDF may develop into cancer through the so-called 'de novo cancer' pathway.

Aim: We investigated whether hypoxia-inducible factor-1α (HIF-1 α) expression in pretreatment biopsies of esophageal cancer is predictive of clinical outcome in patients with esophageal cancer undergoing concurrent chemoradiotherapy (CRT)., Patients and Methods: A total of 25 patients were reviewed. Radiotherapy was administered to total doses of 40-66.6 Gy (median: 66.6 Gy) with a single fraction of 1.8-2 Gy. Cisplatin (80 mg/m2 on day 1) and 5-fluorouracil (800 mg/m2 on days 2-6) were administered concurrently with radiotherapy, every 3-4 weeks to a total of 1-2 courses. Tissue samples from esophageal cancer were obtained from all 25 patients by biopsy before concurrent CRT, and semiquantitative analyses of HIF-1α expression were performed using immunohistochemical staining., Results: High HIF-1α expression was observed in 11 out of 25 patients (42.7%), and HIF-1α expression was significantly correlated with initial response to CRT (p=0.0027). Patients with high HIF-1α expression had significantly poorer local control (LC) (5-year LC: 42.7%) than those with low expression (5-year LC: 72.5%; p=0.0322). Patients with high HIF-1α expression also had significantly lower recurrence-free survival (RFS) (5-year RFS: 18.2%) compared to those with low HIF-1α expression (5-year RFS: 39.8%; p=0.0009), and on multivariate analysis, HIF-1α (p=0.001) and number of chemotherapy courses (p=0.010) were independent prognostic factors for RFS., Conclusion: HIF-1α expression is significantly correlated with initial response to concurrent CRT, and is predictive of RFS for patients with esophageal cancer receiving concurrent CRT.

Adult T-cell leukemia (ATL) is a T-cell malignancy etiologically associated with human T-cell leukemia virus type 1 (HTLV-1). Twist, a highly conserved basic helix-loop-helix transcription factor, is a newly identified oncogene. However, there are no reports on Twist expression in ATL. To define the role of Twist in leukemogenesis of ATL, we examined its expression in T-cell lines and PBMC. HTLV-1-infected T-cell lines and ATL cells expressed high levels of Twist compared with uninfected T-cell lines and normal PBMC. Immunohistochemistry showed immunostaining for Twist in ATL cells in ATL lymph nodes and skin lesions. Infection of normal PBMC with HTLV-1 induced Twist expression. Induction of the viral protein Tax in a human T-cell line led to upregulation of Twist. Tax-induced Twist expression involved the NF-kappaB and CREB signaling pathways. Twist augmented Tax-mediated HTLV-1 LTR and NF-kappaB activation. Short interfering RNA against Twist inhibited cell growth of HTLV-1-infected T-cell lines and downregulation of Twist expression in an HTLV-1-infected T-cell line inhibited the expression of Akt1, interleukin-2 receptor alpha chain, and Tax as well as the known target genes of Twist, YB-1 and Akt2. In conclusion, the results suggest that Tax-induced induction of Twist contributes to leukemogenesis of ATL.

Background: Helicobacter pylori secretes vacuolating cytotoxin (VacA) that damages the gastric epithelium by erosion and loosening of tight junctions. VacA has also immunosuppressive effects, inhibiting interleukin (IL)-2 secretion by interference with the T cell receptor/IL-2 signaling pathway. This study investigated the effect of VacA on gene expression of T cells., Materials and Methods: Gene expression profile of a T cell line, Jurkat, was analyzed by the cDNA microarray technique after VacA challenge. The expression of specific mRNAs was assessed by reverse transcription-polymerase chain reaction. Interleukin (IL)-8 concentrations in culture supernatants and cell surface expression of CD69 were measured by enzyme-linked immunosorbent assay and flow cytometry, respectively. We evaluated nuclear factor-kappaB (NF-kappaB) activation in Jurkat cells challenged with VacA by luciferase assay, electrophoretic mobility shift assay, and Western blot analysis., Results: VacA produced two or greater fold up-regulation of expression of 60 genes. Most of these genes were associated with signal transduction, regulation of gene expression, apoptosis, and inflammation. Up-regulation of four genes (IL8, IL2RA, ICAM1, and CD69) was confirmed. The supernatants of cells incubated with VacA showed significantly higher secretion levels of IL-8 than those incubated without VacA. VacA also induced the cell surface expression of CD69. Since microarray analysis indicated NF-kappaB was involved in the transcriptional activation of the above genes, we examined NF-kappaB signaling pathway. VacA activated NF-kappaB via classical but not alternative pathway., Conclusions: VacA has two paradoxical effects on T cells, immunosuppression, and proinflammatory effects. The latter is mediated by NF-kappaB activation.

There is increasing interest in the use of herbs for the treatment of human diseases including cancer. Therefore, the purpose of this study was to determine whether crude extracts obtained from 44 herbal plants in the Ryukyu Islands might contain components capable of inhibiting the growth of a variety of human colon carcinoma cell lines. Leaves, roots and other parts of the plants were extracted with chloroform, and the crude extracts were dissolved in dimethylsulfoxide and used for the experiments. Extracts of Hemerocallis fulva, Ipomoea batatas, Curcuma longa, and Nasturium officinale caused marked dose-dependent growth inhibition, with IC(50) values in the range of 10-80 mug/ml. With the HCT116 cell line, the extracts of Hemerocallis fulva and Ipomoea batatas induced G1 cell cycle arrest after 48 h of treatment. In addition, we found that extracts of Curcuma longa, and Nasturium officinale induced apoptosis in these cells after 48 h of treatment. The present studies are the first systematic examination of the growth inhibitory effects of crude extracts obtained from herbal plants in the Ryukyu Islands. The findings provide evidence that several plants in the Ryukyu Islands contain components that may have anticancer activity.