Radiolabeled annexin V for imaging apoptosis in radiated human follicular thyroid carcinomas — is an individualized protocol necessary?

Thyroid cancer cells in space during the TEXUS-53 sounding rocket mission - The THYROID Project

Human follicular thyroid cancer cells (FTC-133) were sent to space via a sounding rocket during the TEXUS-53 mission to determine the impact of short-term microgravity on these cells. To enable cell culture and fixation in real microgravity, an automated experiment container (EC) was constructed. In order to ensure safe cell culture, cell-chambers consisting of polycarbonate (PC) material were used. They were highly biocompatible as proved by measuring cell survival using Annexin V flow cytometry. In the follow-up experiment, FTC-133 cells were sent to space via a sounding rocket and were fixed before and after the microgravity (µg) phase with RNAlater. In addition, cells were tested for reactions on hypergravity (hyper-g) as much as 18 g to determine whether worst case acceleration during launch can have an influence on the cells. We investigated genes belonging to biological processes such as cytoskeleton, cell adhesion, tumor growth, angiogenesis and apoptosis. Pathway analyses revealed central functions of VEGFA and EGF. EGF upregulates aspartate beta-hydroxylase (ASPH) which is influencing CASP3. Hyper-g induced a significant up-regulation of TUBB1, VIM, RDX, CAV1, VEGFA and BCL2. FTC-133 cells grown in an automated EC exposed to µg revealed moderate gene expression changes indicating their survival in orbit.

Avenues to molecular imaging of dying cells: Focus on cancer

Successful treatment of cancer patients requires balancing of the dose, timing, and type of therapeutic regimen. Detection of increased cell death may serve as a predictor of the eventual therapeutic success. Imaging of cell death may thus lead to early identification of treatment responders and nonresponders, and to “patient‐tailored therapy.” Cell death in organs and tissues of the human body can be visualized, using positron emission tomography or single‐photon emission computed tomography, although unsolved problems remain concerning target selection, tracer pharmacokinetics, target‐to‐nontarget ratio, and spatial and temporal resolution of the scans. Phosphatidylserine exposure by dying cells has been the most extensively studied imaging target. However, visualization of this process with radiolabeled Annexin A5 has not become routine in the clinical setting. Classification of death modes is no longer based only on cell morphology but also on biochemistry, and apoptosis is no longer found to be the preponderant mechanism of cell death after antitumor therapy, as was earlier believed. These conceptual changes have affected radiochemical efforts. Novel probes targeting changes in membrane permeability, cytoplasmic pH, mitochondrial membrane potential, or caspase activation have recently been explored. In this review, we discuss molecular changes in tumors which can be targeted to visualize cell death and we propose promising biomarkers for future exploration.

Three-dimensional growth of human endothelial cells in an automated cell culture experiment container during the SpaceX CRS-8 ISS space mission - The SPHEROIDS project

Human endothelial cells (ECs) were sent to the International Space Station (ISS) to determine the impact of microgravity on the formation of three-dimensional structures. For this project, an automatic experiment unit (EU) was designed allowing cell culture in space. In order to enable a safe cell culture, cell nourishment and fixation after a pre-programmed timeframe, the materials used for construction of the EUs were tested in regard to their biocompatibility. These tests revealed a high biocompatibility for all parts of the EUs, which were in contact with the cells or the medium used. Most importantly, we found polyether ether ketones for surrounding the incubation chamber, which kept cellular viability above 80% and allowed the cells to adhere as long as they were exposed to normal gravity. After assembling the EU the ECs were cultured therein, where they showed good cell viability at least for 14 days. In addition, the functionality of the automatic medium exchange, and fixation procedures were confirmed. Two days before launch, the ECs were cultured in the EUs, which were afterwards mounted on the SpaceX CRS-8 rocket. 5 and 12 days after launch the cells were fixed. Subsequent analyses revealed a scaffold-free formation of spheroids in space.

Free Radical Scavenging Activity: Antiproliferative and Proteomics Analyses of the Differential Expression of Apoptotic Proteins in MCF-7 Cells Treated with Acetone Leaf Extract of Diospyros lycioides (Ebenaceae)

Breast cancer is the most common cancer in South Africa. The acetone leaf extract of Diospyros lycioides was evaluated qualitatively and quantitatively for its antioxidant potential using DPPH assay and nitric oxide radical scavenging effect, while the viability of MCF-7 cells was evaluated using the MTT. MCF-7 treated cells were stained with Hoechst 335258 dye and annexin-V-FITC to be evaluated for apoptotic effect of the extract, while mRNA expression levels of apoptotic genes were assessed by quantitative real-time PCR and deferential protein expression levels using 2D gel electrophoresis and mass spectrometry. Results revealed presence of antioxidant constituents in the extract. Extract was shown to be cytotoxic in a concentration- and time-dependent manner. Cytotoxicity was demonstrated to be due to apoptosis, with 70% of the extract-treated cells being annexin-V-positive/PI negative at 48 hours. The extract was also shown to upregulate the expression of p53 gene with concomitant downregulation of the Bcl-2 antiapoptotic gene while differentially expressed proteins were identified as enolase, pyruvate kinase, and glyceraldehyde-3-phosphate. The extract in this study was shown to induce apoptosis at an early stage which makes it an ideal source that can be explored for compounds that may be used in the treatment and management of cancer.

Mechanisms of apoptosis in irradiated and sunitinib-treated follicular thyroid cancer cells

The multikinase inhibitor sunitinib (S) seems to have promising potential in the treatment of thyroid cancer. We focused on the impact of S and/or irradiation (R) on mechanisms of apoptosis in follicular thyroid cancer cells. The effects of R, S and their combination were evaluated 2 and 4 days after treatment, using the human thyroid cancer cell line CGTH W-1. The transcription of genes involved in the regulation of apoptosis was investigated using quantitative real-time PCR. Western blot analyses of caspases and survivin were also performed. S elevated BAX (day 4), CASP9, CASP3, BIRC5 (day 4) and PRKACA (day 4) gene expression, whereas the mRNAs of BCL2, CASP8, PRKCA, ERK1, and ERK2 were not significantly changed. S, R and R+S clearly induced caspase-9 protein and elevated caspase-3 activity. Survivin was down-regulated at day 4 in control cells and the expression was blunted by S treatment. R+S induced survivin expression at day 2 followed by a reduction at day 4 of treatment. Sunitinib and the combined application with radiation induced apoptosis in follicular thyroid cancer cells via the intrinsic pathway of apoptosis. In addition, sunitinib might induce apoptosis via decreased expression of the anti-apoptotic protein survivin. These findings suggest the potential use of sunitinib for the treatment of poorly differentiated follicular thyroid carcinomas.

JNK and AKT/GSK3β signaling pathways converge to regulate periodontal ligament cell survival involving XIAP

Periodontal ligament cells (PDLCs) were incubated with H2O2 and the levels of XIAP protein, protein kinase B (AKT), phosphorylated forms of AKT (pAKT), c-Jun N-terminal kinase (JNK), and glycogen synthase kinase-3β (GSK3β) were determined by western immunoblotting or immunocytochemistry. After overexpression and knockdown of XIAP, the AKT, pAKT, JNK and GSK3β levels were determined in PDLCs exposed to H2O2. We demonstrated that 72 h of 250 μM H2O2 exposure resulted in an increase in apoptosis. Meanwhile, XIAP levels were decreased with 72 h of 250 μM H2O2 exposure, while there were also a decrease of JNK2, AKT, pAKT, and GSK3β levels. Such reductions induced by 72 h of 250 μM H2O2 treatment were partially recovered in PDLCs overexpressing XIAP. Interestingly, these reductions (except for pAKT) were mimicked by RNA interference of XIAP. These results suggest that, after 72 h of 250 μM H2O2 exposure, Akt, JNK, and GSK3β intracellular kinase signaling pathways converge to regulate PDLC survival involving XIAP.

Enhancement of recombinant myricetin on the radiosensitivity of lung cancer A549 and H1299 cells

Objective

Myricetin, a common dietary flavonoid is widely distributed in fruits and vegetables, and is used as a health food supplement based on its immune function, anti-oxidation, anti-tumor, and anti-inflammatory properties. The aim of this study was to investigate the effects of myricetin on combination with radiotherapy enhance radiosensitivity of lung cancer A549 and H1299 cells.

Methods

A549 cells and H1299 cells were exposed to X-ray with or without myricetin treatment. Colony formation assays, CCK-8 assay, flow cytometry and Caspase-3 level detection were used to evaluate the radiosensitization activity of myricetin on cell proliferation and apoptosis in vitro. Nude mouse tumor xenograft model was built to assessed radiosensitization effect of myricetin in vivo.

Results

Compared with the exposed group without myricetin treatment, the groups treated with myricetin showed significantly suppressed cell surviving fraction and proliferation, increased the cell apoptosis and increased Caspase-3 protein expression after X-ray exposure in vitro. And in vivo assay, growth speed of tumor xenografts was significantly decreased in irradiated mice treated with myricetin.

Conclusions

The study demonstrated both in vitro and in vivo evidence that combination of myricetin with radiotherapy can enhance tumor radiosensitivity of pulmonary carcinoma A549 and H1299 cells, and myricetin could be a potential radiosensitizer for lung cancer therapy.

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5791518001210633

Spheroid formation of human thyroid cancer cells in an automated culturing system during the Shenzhou-8 Space mission

Human follicular thyroid cancer cells were cultured in Space to investigate the impact of microgravity on 3D growth. For this purpose, we designed and constructed a cell container that can endure enhanced physical forces, is connected to fluid storage chambers, performs media changes and cell harvesting automatically and supports cell viability. The container consists of a cell suspension chamber, two reserve tanks for medium and fixative and a pump for fluid exchange. The selected materials proved durable, non-cytotoxic, and did not inactivate RNAlater. This container was operated automatically during the unmanned Shenzhou-8 Space mission. FTC-133 human follicular thyroid cancer cells were cultured in Space for 10 days. Culture medium was exchanged after 5 days in Space and the cells were fixed after 10 days. The experiment revealed a scaffold-free formation of extraordinary large three-dimensional aggregates by thyroid cancer cells with altered expression of EGF and CTGF genes under real microgravity.

How and why does the proteome respond to microgravity?

For medical and biotechnological reasons, it is important to study mammalian cells, animals, bacteria and plants exposed to simulated and real microgravity. It is necessary to detect the cellular changes that cause the medical problems often observed in astronauts, cosmonauts or animals returning from prolonged space missions. In order for in vitro tissue engineering under microgravity conditions to succeed, the features of the cell that change need to be known. In this article, we summarize current knowledge about the effects of microgravity on the proteome in different cell types. Many studies suggest that the effects of microgravity on major cell functions depend on the responding cell type. Here, we discuss and speculate how and why the proteome responds to microgravity, focusing on proteomic discoveries and their future potential.

Questioning the value of (99m)Tc-HYNIC-annexin V based response monitoring after docetaxel treatment in a mouse model for hereditary breast cancer

Annexin V imaging is suggested to provide a good indication of cancer treatment efficacy. To study the accuracy of (99m)Tc-AnxV imaging, we monitored chemo-sensitive and chemo-resistant tumors in a mouse breast cancer model after treatment with docetaxel. Sensitive tumors showed a slight peak in (99m)Tc-AnxV uptake one day post-treatment, while uptake in resistant tumors remained constant. In contrast to immunohistochemical analysis, (99m)Tc-AnxV imaging could not be used to predict tumor response, due to large variation between animals.

Different responsiveness of endothelial cells to vascular endothelial growth factor and basic fibroblast growth factor added to culture media under gravity and simulated microgravity

When incubated under simulated microgravity (s-microg), endothelial cells (EC) form tubular structures that resemble vascular intimas. This delayed formation of 3D EC structures begins between the 5th and 7th day of culturing EC under conditions of s-microg, when double-row cell assemblies become visible. With the aim of learning about this initial phase of tubular structure formation, we found that NFkappaBp65 protein content was similar in all cell populations, but gene and protein expression of phosphokinase A catalytic subunit, phosphokinase Calpha, and extracellular signal-regulated kinases 1 and 2 was altered in cells cultured under s-microg. Apoptosis remained below 30% in all EC cultures. In contrast to controls, the 7-day-old s-microg cultures contained 3D aggregates with proliferating cells, enhanced numbers of necrotic cells, and osteopontin-negative EC as well as supernatants with reduced quantities of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), soluble TNFRSF5, TNFSF5, intercellular adhesion molecule-1, tumor necrosis factor receptor 2, IL-18, complement C3, and von Willebrand factor. VEGF and/or bFGF (10 ng/mL) application influenced the accumulation of proteins in supernatants more profoundly under 1 g than under s-microg. These findings provide evidence that phosphokinase Calpha plays a key role in tube formation. Improving the interaction of VEGF and/or bFGF with EC under s-microg could enhance the engineering of vascular intimas.

Changes of apoptosis, p53, and bcl-2 by irradiation in poorly differentiated thyroid carcinoma cell lines: a prognostic marker for the prospect of therapeutic success?

BACKGROUND

Poorly differentiated thyroid carcinoma (PDTC) has an unfavorable prognosis. Surgical management is the principal treatment approach. In addition, radioiodine treatment and external beam radiotherapy (EBRT) are given to reduce the risk of local relapse. Despite aggressive therapy, the response to treatment tends to become increasingly poorer over time. The objective of this study was to investigate the induction of apoptosis by EBRT as a function of p53 and bcl-2 protein levels in PDTC. The predictive value of these molecules with respect to treatment efficacy was evaluated.

MATERIALS AND METHODS

Two different cell lines of PDTC (FTC-133 and ML-1) were irradiated with a dose of 30 Gy. Apoptotic cells were quantified using terminal deoxynucleotidyltransferase-dUTP nick-end labeling staining without irradiation, 48 and 96 hours after irradiation. The protein levels of p53 and bcl-2 were measured simultaneously using flow cytometry and western blotting. The cell cycle distribution was determined.

RESULTS

Untreated FTC-133 cells showed a high rate of apoptosis, a high protein level of p53, and a low bcl-2 protein level. Forty-eight hours after irradiation, a slight reduction in apoptotic cells was observed in conjunction with an increase in bcl-2 and p53 protein levels. The slightly reduced fraction of apoptotic cells remained at the same level up to 96 hours after irradiation, whereas the p53 protein level was further downregulated. The cell cycle distribution showed a significant G2/M arrest after 48 hours and recovery 96 hours after irradiation. ML-1 cells did not show any detectable p53 levels and revealed a low rate of apoptosis which significantly increased 48 hours after irradiation. Ninety-six hours after irradiation, a decrease in apoptosis was detectable. The protein level of bcl-2 increased significantly within 48 hours and decreased 96 hours after irradiation. The cell cycle distribution showed a G2/M arrest after 48 hours without a recovery 96 hours after irradiation.

CONCLUSIONS

The p53 and bcl-2 expression profiles and the observed apoptotic rates of FTC-133 and ML-1 under irradiation are consistent with a more aggressive FTC-133 phenotype. Alterations in p53- and bcl-2 protein levels yield predictive information for EBRT efficacy.