The occurrence of metastasis, an important breast cancer prognostic factor, depends on cell migration/invasion mechanisms, which can be controlled by regulatory and effector molecules such as Rho-associated kinase protein (ROCK-1). Increased expression of this protein promotes tumor growth and metastasis, which can be restricted by ROCK-1 inhibitors. Melatonin has shown oncostatic, antimetastatic, and anti-angiogenic effects and can modulate ROCK-1 expression. Metastatic and nonmetastatic breast cancer cell lines were treated with melatonin as well as with specific ROCK-1 inhibitor (Y27632). Cell viability, cell migration/invasion, and ROCK-1 gene expression and protein expression were determined in vitro. In vivo lung metastasis study was performed using female athymic nude mice treated with either melatonin or Y27832 for 2 and 5 wk. The metastases were evaluated by X-ray computed tomography and single photon emission computed tomography (SPECT) and by immunohistochemistry for ROCK-1 and cytokeratin proteins. Melatonin and Y27632 treatments reduced cell viability and invasion/migration of both cell lines and decreased ROCK-1 gene expression in metastatic cells and protein expression in nonmetastatic cell line. The numbers of ‘hot’ spots (lung metastasis) identified by SPECT images were significantly lower in treated groups. ROCK-1 protein expression also was decreased in metastatic foci of treated groups. Melatonin has shown to be effective in controlling metastatic breast cancer in vitro and in vivo, not only via inhibition of the proliferation of tumor cells but also through direct antagonism of metastatic mechanism of cells rendered by ROCK-1 inhibition. When Y27632 was used, the effects were similar to those found with melatonin treatment.
Group B Streptococcus (GBS) carriage by pregnant women is the primary risk factor for early-onset GBS neonatal sepsis. Intrapartum antibiotic prophylaxis (IAP) can prevent this transmission route, and two main approaches are recommended to base the selection of pregnant women to be submitted to IAP: the risk-based and the culture-based strategies. In Brazil, compliance to such recommendations is poor, and not much is known about GBS carriage. In the present study, 3,647 pregnant women living in Rio de Janeiro State, Brazil, were screened for GBS anogenital colonization, over a period of 8 years (2008–2015). GBS was detected in 956 (26.2%) of them, and presence of vaginal discharge was the only trait associated with a higher risk for GBS colonization. Serotypes Ia (257; 37.3%) and II (137; 19.9%) were the most frequent among 689 (72.1% of the total) GBS isolates evaluated, followed by NT isolates (84; 12.1%), serotype Ib (77; 11.1%), V (63; 9.1%), III (47; 6.8%) and IV (24; 3.5%). Estimated coverage of major serotype-based GBS vaccines currently under clinical trials would vary from 65.2% to 84.3%. All 689 isolates tested were susceptible to ampicillin and vancomycin. Resistance to chloramphenicol, clindamycin, erythromycin, levofloxacin, and tetracycline was observed in 5% (35), 2% (14), 14% (97), 5% (35) and 86% (592) of the isolates, respectively. No significant fluctuations in colonization rates, serotype distribution and antimicrobial susceptibility profiles were observed throughout the period of time investigated. The culture-based approach for IAP recommendation showed to be the best choice for the population investigated when compared to the risk-based, since the first did not increase the number of pregnant women submitted to antibiotic therapy and covered a larger number of women who were actually colonized by GBS. The fact the not all isolates were available for additional characterization, and serotype IX antiserum was not available for testing represent limitations of this study. Nevertheless, to the best of our knowledge, this is the largest investigation on GBS carriage among pregnant women in Brazil up to date, and results are useful for improving GBS prevention and treatment strategies.
Our data indicate that TLR2 -196 to -174 del and TLR4+896G may increase the risk of gastric cancer in a Brazilian population.
Functional polymorphisms in promoter regions can produce changes in the affinity of transcription factors, thus altering the messenger ribonucleic acid (mRNA) expression levels of inflammatory cytokines associated with the risk of cancer development. The goal of this study was to evaluate the influence that polymorphisms in the cytokine genes known as TNF-α-308 G/A (rs1800629), TNF-α-857 C/T (rs1799724), IL-8-251 T/A (rs4073), IL-8-845 T/C (rs2227532), and IL-10-592 C/A (rs1800872) have on changes to mRNA expression levels and on the risks of chronic gastritis (CG) and gastric cancer (GC). A sample of 723 individuals was genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Relative mRNA expression levels were measured using quantitative real-time PCR (qPCR). Polymorphisms TNF-α-308 G/A and IL-8-251 A/T were not associated with risks of these gastric lesions. However, TNF-α-857 C/T, IL-8-845 T/C, and IL-10-592 C/A were found to be associated with a higher risk of GC, and IL-10-592 C/A was found to be associated with a higher risk of CG. The relative mRNA expression levels (RQ) of TNF-α, IL-8, and IL-10 were markedly downregulated in the CG group (median RQs = 0.128, 0.247, and 0.614, respectively), while the RQ levels of TNF-α in the GC group were upregulated (RQ = 2.749), but were basal for IL-8 (RQ = 1.053) and downregulated for IL-10 (RQ = 0.179). When the groups were stratified according to wild-type and polymorphic alleles, only for IL-8-845 T/C the polymorphic allele was found to influence the expression levels of this cytokine. IL-8-845 C allele carriers were significantly upregulated in both groups (GC and CG; RQ = 3.138 and 2.181, respectively) when compared to TT homozygotes (RQ = -0.407 and 0.165, respectively). In silico analysis in the IL-8 promoter region revealed that the presence of the variant C allele in position -845 is responsible for the presence of the binding sites for two transcription factors (REL and CREB1), which are involved in increased gene expression. Polymorphic alleles were not shown to have any effect on the expression levels of TNF-α and IL-10. Taken together, our findings provide evidence for an association of TNF-α-857 C/T, IL-8-845 T/C, and IL-10-592 C/A with a higher risk of gastric cancer and also demonstrate the influence that the polymorphic C allele of IL-8-845 has on changes to the gene expression levels of this cytokine.
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