Different effects of H2O2 treatment on cervical squamous carcinoma cells and adenocarcinoma cells

Antioxidative and anti-inflammatory effects of taxifolin in H2O2-induced oxidative stress in HTR-8/SVneo trophoblast cell line

Oxidative stress has been implicated in numerous pregnancy-related disorders. Biologically active plant secondary metabolites, which are present in everyday diet, could prove effective therapeutic agents in preventing these disorders. This study evaluated effects of taxifolin (dihydroquercetin) on ROS production, markers of oxidative damage to lipids and proteins, activity of antioxidant enzymes and production of pro-inflammatory cytokines in H2O2-induced oxidative stress in trophoblast HTR-8/SVneo cells. Taxifolin in 10 µM and 100 µM concentrations attenuated oxidative damage to lipids and proteins, as evidenced by a decrease in MDA content, extracellular LDH activity, carbonyl groups and nitrite contents. A reduction in the activity of antioxidant enzymes SOD, CAT and GPx in cells pre-treated with taxifolin, prior to H2O2 exposure, was also observed, along with a reduction in intracellular ROS production. Both evaluated concentrations of taxifolin showed anti-inflammatory activity in trophoblast cells, by reducing production of pro-inflammatory cytokines IL-1β and IL-6. In this model of H2O2-induced oxidative stress, taxifolin showed marked antioxidative and anti-inflammatory activities in trophoblast cells, adding further evidence of its protective effects and showing potential as a therapeutic agent in preventing adverse pregnancy outcomes.

Live Imaging of Label-Free Graphene Oxide Reveals Critical Factors Causing Oxidative-Stress-Mediated Cellular Responses

The interest in graphene and its translation into commercial products has been expanding at a high pace. Based on previously described pulmonary safety concerns for carbon nanomaterials, there is a great need to define parameters guiding interactions between graphene-based materials and the pulmonary system. The aim of the present study was to determine the importance of two critical parameters: lateral dimensions of the material and coating with proteins in relation to each other and their pulmonary impact. Endotoxin-free materials with distinct lateral dimensions, s-GO (50-200 nm) and l-GO (5-15 μm), were produced and thoroughly characterized. Exploiting intrinsic fluorescence of graphene oxide (GO) and using confocal live-cell imaging, the behavior of the cells in response to the material was visualized in real time. Although BEAS-2B cells internalized GO efficiently, l-GO was linked to higher plasma membrane interactions correlated with elevated reactive oxygen species (ROS) levels, pro-inflammatory response, and greater cytotoxicity, in agreement with the oxidative stress paradigm. For both GO types, the presence of serum alleviated lipid peroxidation of plasma membrane and decreased intracellular ROS levels. However, protein coating was not enough to entirely mitigate toxicity and inflammatory response induced by l-GO. In vitro results were validated in vivo, as l-GO was more prone to induce pulmonary granulomatous response in mice compared to s-GO. In conclusion, the lateral dimension of GO played a more important role than serum protein coating in determining biological responses to the material. It was also demonstrated that time-lapse imaging of live cells interacting with label-free GO sheets can be used as a tool to assess GO-induced cytotoxicity.

Inversed Expression Patterns of S100A4 and E-Cadherin in Cervical Cancers: Implication in Epithelial-Mesenchymal Transition

Cervical cancer/CC is the third commonest female malignancy worldwide. The aggressive growth and distal metastases are the leading causes of CC mortality, which is largely due to epithelial-mesenchymal transition/EMT. Fibroblast specific protein S100A4 promotes cancer metastasis and epithelial type cadherin/E-cadherin play pivotal roles in cell-cell and cell-extracellular matrix interaction. Therefore, the expression patterns of S100A4 and E-cadherin reflect statuses of EMT of carcinoma cells. However, S100A4 expression and its relevance with E-cadherin and HPV16 infection in cervical cancers remain unknown. This study aims to address the above issues using cervical cancer specimens. Immunohistochemistry reveals that the levels of mesenchymal marker S100A4 is upregulated (>++) in cervical adenocarcinomas/CACs (12/16; 75%) and squamous cell carcinomas/CSCCs (23/28; 82%) than that in noncancerous glandular epithelia/GE (0/12; 0%) and squamous epithelia/SE (0/12; 0%). Epithelial marker membranous E-cadherin is remarkably reduced on the surface of CAC and CSCC cells (P = 0.00; P = 0.00), especially those showing poorly differentiated phenotypes (P < 0.05) in comparison with their noncancerous counterparts. Correlative analyses revealed an inverse relationship between S100A4 and E-cadherin expression among the cervical cancer samples (P = 0.01, r = -0.38). S100A4 expression level in HPV16-infected group is higher than that in HPV16-free group (P = 0.02). These results suggest the close correlation of S100A4 upregulation with cervical cancer formation and HPV16 infection and E-cadherin reduction with the grades of CC dedifferentiation. The concurrent gain of S100A4 and loss of membrane E-cadherin suggest EMT tendency of CC cells and can be regarded as an unfavorable prognostic parameter of CC patients. Anat Rec, 300:2184-2191, 2017. © 2017 Wiley Periodicals, Inc.