15 research outputs found
G1 checkpoint protein and p53 abnormalities occur in most invasive transitional cell carcinomas of the urinary bladder
The G1 cell cycle checkpoint regulates entry into S phase for normal cells. Components of the G1 checkpoint, including retinoblastoma (Rb) protein, cyclin D1 and p16INK4a, are commonly altered in human malignancies, abrogating cell cycle control. Using immunohistochemistry, we examined 79 invasive transitional cell carcinomas of the urinary bladder treated by cystectomy, for loss of Rb or p16INK4a protein and for cyclin D1 overexpression. As p53 is also involved in cell cycle control, its expression was studied as well. Rb protein loss occurred in 23/79 cases (29%); it was inversely correlated with loss of p16INK4a, which occurred in 15/79 cases (19%). One biphenotypic case, with Rb+p16– and Rb-p16+ areas, was identified as well. Cyclin D1 was overexpressed in 21/79 carcinomas (27%), all of which retained Rb protein. Fifty of 79 tumours (63%) showed aberrant accumulation of p53 protein; p53 staining did not correlate with Rb, p16INK4a, or cyclin D1 status. Overall, 70% of bladder carcinomas showed abnormalities in one or more of the intrinsic proteins of the G1 checkpoint (Rb, p16INK4a and cyclin D1). Only 15% of all bladder carcinomas (12/79) showed a normal phenotype for all four proteins. In a multivariate survival analysis, cyclin D1 overexpression was linked to less aggressive disease and relatively favourable outcome. In our series, Rb, p16INK4a and p53 status did not reach statistical significance as prognostic factors. In conclusion, G1 restriction point defects can be identified in the majority of bladder carcinomas. Our findings support the hypothesis that cyclin D1 and p16INK4a can cooperate to dysregulate the cell cycle, but that loss of Rb protein abolishes the G1 checkpoint completely, removing any selective advantage for cells that alter additional cell cycle proteins. © 1999 Cancer Research Campaig
A Randomized Controlled Trial of a Literacy-Sensitive Self-Management Intervention for Chronic Obstructive Pulmonary Disease Patients
BACKGROUND: Low literacy skills are common and associated with a variety of poor health outcomes. This may be particularly important in patients with chronic illnesses such as chronic obstructive pulmonary disease (COPD) that require appropriate inhaler technique to maintain quality of life and avoid exacerbations. OBJECTIVE: To explore the impact of a literacy-sensitive self-management intervention on inhaler technique scores in COPD patients and to determine if effects differ by literacy. DESIGN: Randomized controlled trial. PARTICIPANTS: Ninety-nine patients with COPD. INTERVENTION: Patients were randomly assigned to a one-on-one self-management educational intervention or usual care. The intervention focused on inhaler technique, smoking cessation, and using a COPD action plan. MAIN MEASURES: At baseline, an inhaler technique assessment, literacy assessment, health-related quality of life questionnaires, and pulmonary function tests were completed. Inhaler technique was re-evaluated after two to eight weeks. KEY RESULTS: Mean age 63, 65% female, 69% Caucasian, moderate COPD severity on average, 36% with low literacy, moderately impaired health-related quality of life, and similar baseline metered dose inhaler technique scores. Patients in the intervention group had greater mean improvement from baseline in metered dose inhaler technique score compared to those in the usual care group (difference in mean change 2.1, 95% CI 1.1, 3.0). The patients in the intervention group also had greater mean improvements in metered dose inhaler technique score than those in the usual care group whether they had low health literacy (difference in mean change 2.8, 95% CI 0.6, 4.9) or higher health literacy (1.8, 95% CI 0.7, 2.9). CONCLUSIONS: A literacy-sensitive self-management intervention can lead to improvements in inhaler technique, with benefits for patients with both low and higher health literacy. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11606-011-1867-6) contains supplementary material, which is available to authorized users
Active TGF-β signaling and decreased expression of PTEN separates angiosarcoma of bone from its soft tissue counterpart
Angiosarcomas constitute a heterogeneous group of highly malignant vascular tumors. Angiosarcoma of bone is rare and poorly characterized. For angiosarcoma of soft tissue, some pathways seem to be involved in tumor development. Our aim was to evaluate the role of these pathways in angiosarcoma of bone. We collected 37 primary angiosarcomas of bone and used 20 angiosarcomas of soft tissue for comparison. Immunohistochemistry was performed on constructed tissue microarrays to evaluate expression of CDKN2A, TP53, PTEN, BCL2, CDK4, MDM2, cyclin D1, β-catenin, transforming growth factor-β (TGF-β), CD105, phospho-Smad1, phospho-Smad2, hypoxia-inducible factor-1α, plasminogen activator inhibitor type 1 (PAI-1), VEGF, CD117 and glucose transporter--1. PIK3CA was screened for hotspot mutations in 19 angiosarcomas. In nearly 55% of the angiosarcoma of bone, the retinoblastoma (Rb) pathway was affected. Loss of CDKN2A expression was associated with a significantly worse prognosis. No overexpression of TP53 or MDM2 was found, suggesting that the TP53 pathway is not important in angiosarcoma of bone. Angiosarcoma of bone showed highly active TGF-β signaling with immunoreactivity for phospho-Smad2 and PAI-1. Although the phosphatidylinositol 3-kinase (PI3K)/Akt pathway seems to be active in both tumor groups, different mechanisms were involved: 41% of angiosarcoma of bone showed a decrease in expression of PTEN, whereas in angiosarcoma of soft tissue overexpression of KIT was found (90%). PIK3CA hotspot mutations were absent. In conclusion, the Rb pathway is involved in tumorigenesis of angiosarcoma of bone. The PI3K/Akt pathway is activated in both angiosarcoma of bone and soft tissue, however, with a different cause; PTEN expression is decreased in angiosarcoma of bone, whereas angiosarcomas of soft tissue show overexpression of KIT. Our findings support that angiosarcomas are a heterogeneous group of vascular malignancies. Both angiosarcoma of bone and soft tissue may benefit from therapeutic strategies targeting the PI3K/Akt pathway. However, interference with TGF-β signaling may be specifically relevant in angiosarcoma of bone.Modern Pathology advance online publication, 19 April 2013; doi:10.1038/modpathol.2013.56