SOX2-RNAi attenuates S-phase entry and induces RhoA-dependent switch to protease-independent amoeboid migration in human glioma cells

<p>Abstract</p> <p>Background</p> <p>SOX2, a high mobility group (HMG)-box containing transcription factor, is a key regulator during development of the nervous system and a persistent marker of neural stem cells. Recent studies suggested a role of SOX2 in tumor progression. In our previous work we detected SOX2 in glioma cells and glioblastoma specimens. Herein, we aim to explore the role of SOX2 for glioma malignancy in particular its role in cell proliferation and migration.</p> <p>Methods</p> <p>Retroviral shRNA-vectors were utilized to stably knockdown SOX2 in U343-MG and U373-MG cells. The resulting phenotype was investigated by Western blot, migration/invasion assays, RhoA G-LISA, time lapse video imaging, and orthotopic xenograft experiments.</p> <p>Results</p> <p>SOX2 depletion results in pleiotropic effects including attenuated cell proliferation caused by decreased levels of cyclinD1. Also an increased TCF/LEF-signaling and concomitant decrease in Oct4 and Nestin expression was noted. Furthermore, down-regulation of focal adhesion kinase (FAK) signaling and of downstream proteins such as HEF1/NEDD9, matrix metalloproteinases pro-MMP-1 and -2 impaired invasive proteolysis-dependent migration. Yet, cells with knockdown of SOX2 switched to a RhoA-dependent amoeboid-like migration mode which could be blocked by the ROCK inhibitor Y27632 downstream of RhoA-signaling. Orthotopic xenograft experiments revealed a higher tumorigenicity of U343-MG glioma cells transduced with shRNA targeting SOX2 which was characterized by increased dissemination of glioma cells.</p> <p>Conclusion</p> <p>Our findings suggest that SOX2 plays a role in the maintenance of a less differentiated glioma cell phenotype. In addition, the results indicate a critical role of SOX2 in adhesion and migration of malignant gliomas.</p

Infrared Spectroscopic Studies of Cells and Tissues: Triple Helix Proteins as a Potential Biomarker for Tumors

In this work, the infrared (IR) spectra of living neural cells in suspension, native brain tissue, and native brain tumor tissue were investigated. Methods were developed to overcome the strong IR signal of liquid water so that the signal from the cellular biochemicals could be seen. Measurements could be performed during surgeries, within minutes after resection. Comparison between normal tissue, different cell lineages in suspension, and tumors allowed preliminary assignments of IR bands to be made. The most dramatic difference between tissues and cells was found to be in weaker IR absorbances usually assigned to the triple helix of collagens. Triple helix domains are common in larger structural proteins, and are typically found in the extracellular matrix (ECM) of tissues. An algorithm to correct offsets and calculate the band heights and positions of these bands was developed, so the variance between identical measurements could be assessed. The initial results indicate the triple helix signal is surprisingly consistent between different individuals, and is altered in tumor tissues. Taken together, these preliminary investigations indicate this triple helix signal may be a reliable biomarker for a tumor-like microenvironment. Thus, this signal has potential to aid in the intra-operational delineation of brain tumor borders. © 2013 Stelling et al

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI &lt;18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For school&#x2;aged children and adolescents, we report thinness (BMI &lt;2 SD below the median of the WHO growth reference) and obesity (BMI &gt;2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesit

Histopathological investigation of different MCAO modalities and impact of autologous bone marrow mononuclear cell administration in an ovine stroke model

Translational researchers and clinicians recommend the use of large animal models in preclinical stroke research. This represents an important part of a strategy aiming to prevent past translational failures in future therapeutic developments. Thirty-five Merino rams were subjected to sham surgery (n = 3), one-branch middle cerebral artery occlusion (MCAO, n = 8) or total MCAO (n = 24). Twelve animals from the latter group received intravenous administration of 4 × 10(6) autologous mononuclear bone marrow cells (BM MNC) per kilogram 24 h after total MCAO. Animals were sacrificed at day 49 post MCAO. Histological investigations were performed to reveal (1) the impact of different MCAO modalities on a cellular level and (2) the influence of BM MNC therapy following stroke. Clear differences between one-branch and total MCAO were observed histologically with results being comparable to those seen in human patients. BM MNC treatment reduced final lesion extension, lymphocytic infiltration and axonal degeneration after MCAO. The sheep model may represent a feasible tool for translational stroke research as pathohistological findings mimic the situation in humans. Histological evidence was found for beneficial impact of autologous BM MNC therapy. Further studies are needed to assess the neurofunctional impact of the approach in the gyrencephalic brain

An Extremely Rare, Remote Intracerebral Metastasis of Oral Cavity Cancer: A Case Report

Distant brain metastases from oral squamous cell carcinomas (OSCC) are extremely rare. Here we describe a case of a 53-year-old man with a primary OSCC who referred to the neurosurgical department because of epileptic seizures. MR imaging revealed an enhancing lesion in the right parietal lobe. A craniotomy with tumor removing was performed. Histopathological examination verified an invasive, minimally differentiated metastasis of the primary OSCC. The patient refused whole brain radiation therapy and died from pulmonary metastatic disease 10 months after the neurosurgical intervention without any cerebral recurrence. To the authors’ knowledge, only two similar cases have been previously reported

Giant cell glioblastoma is associated with altered aurora b expression and concomitant p53 mutation

Giant cell glioblastoma (gcGB), a subtype of GB, is characterized by the presence of numerous multinucleated giant cells. The prognosis for gcGB is poor, but it may have a better clinical outcome compared with classic GB. The molecular alterations that lead to the multinucleated cell phenotype of gcGB have not been elucidated. Giant cell GB has a higher frequency of the tumor suppressor protein p53 mutations than GB, however, and a role for the mitotic Aurora B kinase has been suggested. We analyzed Aurora B expression in gcGB (n = 28) and GB (n = 54) patient tumor samples by immunohistochemistry; 17 gcGB and 22 GB samples were analyzed at the DNA and mRNA levels. No mutations in the Aurora B gene (AURKB) were found, but its mRNA and protein levels were significantly higher in gcGB than in GB. Fifty-nine percent of gcGB samples but only 18% of the GB samples showed p53 mutations. Ectopic overexpression of Aurora B induced a significant increase inthe proportion of multinucleated cells in p53 mutant U373-MG, but not in p53 wild-type U87-MG, glioma cells. RNAi of p53 in U87-MG cells led to an increase in the fraction of multinucleated cells that was further augmented by ectopic overexpression of Aurora B. These results suggest that loss of p53 function and dysregulated Aurora B protein levels might represent factors that drive the development of multinucleated cells in gcGB