Vimentin Overexpression Contributes To the Biological Properties of Metastatic Head and Neck Cancer Cells

Epithelial to mesenchymal transition occurs in the later stages of epithelial tumor progression, with cells expressing mesenchymal markers. Of these, the intermediate filament protein vimentin is frequently upregulated in metastatic carcinomas. Previously, microarray studies showed that the gene encoding vimentin is highly upregulated in metastatic HN12 cells compared to a related primary tumor cell line. In this study, we confirmed this difference using real-time quantitative PCR, western blot analysis, and immunostaining. Furthermore, EGF and TGF-β, growth factors that induce migration and invasion of HN12 cells, produced synergistic increases in vimentin expression. To assess the contribution of vimentin to the biological properties, HN12 cells were stably transfected with a plasmid that directs synthesis of vimentin shRNA. Clones expressing decreased amounts of vimentin were isolated and characterized. These cells showed significantly reduced proliferation compared to non-targeting controls. Moreover, downregulation of vimentin led to a decrease in cell motility, as well as reducing their ability to invade through a basement membrane substitute. Using transient transfection assays, vimentin promoter activity was determined in HN12 cells to define regulatory elements important for controlling vimentin upregulation in the absence or presence of EGF and TGF-β. Taken together, the data indicate that overexpression of vimentin is important for proliferation and invasion of metastatic HN12 cells, and suggest that EGF- dependent pathways target binding elements in the proximal vimentin promoter, while TGF-β is likely to act in an AP1-dependent manner. Furthermore, both growth factors appear to synergize by stimulating promoter activation through the ASE site, suggesting involvement of Stat-dependent pathways in regulation of vimentin expression in HN12 cells

The effect of latency on bone lengthening force and bone mineralization: an investigation using strain gauge mounted on internal distractor device

BACKGROUND: The purpose of this study was to investigate the effect of latency on the development of bone lengthening force and bone mineralization during mandible distraction osteogenesis. METHODS: Distraction tensions were investigated at different latency period in 36 rabbits using internal unilateral distractor. Strain gauges were prepared and attached to the distractor to directly assess the level of distraction tension during mandible lengthening. The tensile force environment of the mandible of rabbit during distraction was evaluated through in vivo experiments using two gauges. The animals were divided into 3 groups each containing 12 rabbits. Latency periods of 0, 4 and 7 days respectively were observed prior to beginning distraction. The distraction protocol consisted of a lengthening rate of 1 mm once daily for 8 days, followed by a consolidation phase of 2 weeks after which the animals were killed. Biopsies specimens were taken from the distracted area at the end of the distraction period. A non-distracted area of the mandible bone served as control. The specimens were analyzed by scanning electron microscopy to assess the ultrastructural pattern, and the bone mineralization. RESULTS: The resting tension acting on the distraction gap increases through distraction. The 7-day latency groups exhibit higher tension then those of 0-day and 4-days latency groups. Quantitative energy dispersive spectral analysis confirmed that immediate distractions were associated with lower calcium and phosphate atomic weight ratio. CONCLUSION: the latency periods could affect the bone lengthening tension and the bone mineralization process

Analysis of metallothionein and vimentin immunoreactivity in pharyngeal squamous cell carcinoma and its microenvironment

Metallothionein (MT) has been shown to have pro-proliferative anti-apoptotic activity and to be involved in microenvironment remodeling. The aim of this study has been to determine whether the changes in MT and vimentin immunoreactivity observed in cancer and its microenvironment are related to the local spread of the disease. The immunoreactivity levels of both MT and vimentin were evaluated together with CD56 and CD57 antigens in 49 tissue samples taken from patients with squamous cell carcinoma originating from the palatine tonsils and in 20 tissue samples derived from patients with chronic tonsillitis (the reference group). MT immunoreactivity levels were statistically significantly higher in the tissue samples from squamous cell carcinoma than in those of the reference group and also higher in the squamous cell carcinoma samples compared with the stromal samples. Moreover, stromal fibroblasts exhibited high vimentin and MT immunoreactivity levels. Statistically significantly higher MT immunoreactivity levels within the tumor cells were identified in patients with the presence of lymph node metastases in contrast to those patients without such metastases. Vimentin was detected in both the tumor and the stromal tissue samples and presented an interesting pattern of staining strongly expressed within the stroma and the septal architecture of the tumor. The number of CD56- and CD57-positive lymphocytes identified in tissue samples both from squamous cell carcinoma and from the stroma was statistically significantly lower than that in the reference group. MT expression by tumor cells is thus associated with an aggressive phenotype of the tumor and the ability to create metastases

Managing hypertension in rural Uganda: Realities and strategies 10 years of experience at a district hospital chronic disease clinic.

The literature on the global burden of noncommunicable diseases (NCDs) contrasts a spiraling epidemic centered in low-income countries with low levels of awareness, risk factor control, infrastructure, personnel and funding. There are few data-based reports of broad and interconnected strategies to address these challenges where they hit hardest. Kisoro district in Southwest Uganda is rural, remote, over-populated and poor, the majority of its population working as subsistence farmers. This paper describes the 10-year experience of a tri-partite collaboration between Kisoro District Hospital, a New York teaching hospital, and a US-based NGO delivering hypertension services to the district. Using data from patient and pharmacy registers and a random sample of charts reviewed manually, we describe both common and often-overlooked barriers to quality care (clinic overcrowding, drug stockouts, provider shortages, visit non-adherence, and uninformative medical records) and strategies adopted to address these barriers (locally-adapted treatment guidelines, patient-clinic-pharmacy cost sharing, appointment systems, workforce development, patient-provider continuity initiatives, and ongoing data monitoring). We find that: 1) although following CVD risk-based treatment guidelines could safely allocate scarce medications to the highest-risk patients first, national guidelines emphasizing treatment at blood pressures over 140/90 mmHg ignore the reality of "stockouts" and conflict with this goal; 2) often-overlooked barriers to quality care such as poor quality medical records, clinic disorganization and local employment practices are surmountable; 3) cost-sharing initiatives partially fill the gap during stockouts of government supplied medications, but still may be insufficient for the poorest patients; 4) frequent prolonged lapses in care may be the norm for most known hypertensives in rural SSA, and 5) ongoing data monitoring can identify local barriers to quality care and provide the impetus to ameliorate them. We anticipate that our 10-year experience adapting to the complex challenges of hypertension management and a granular description of the solutions we devised will be of benefit to others managing chronic disease in similar rural African communities