u-PAR expression in cancer associated fibroblast: new acquisitions in multiple myeloma progression

BACKGROUND: Multiple Myeloma (MM) is a B-cell malignancy in which clonal plasma cells progressively expand within the bone marrow (BM) as effect of complex interactions with extracellular matrix and a number of microenvironmental cells. Among these, cancer-associated fibroblasts (CAF) mediate crucial reciprocal signals with MM cells and are associated to aggressive disease and poor prognosis. A large body of evidence emphasizes the role of the urokinase plasminogen activator (u-PA) and its receptor u-PAR in potentiating the invasion capacity of tumor plasma cells, but little is known about their role in the biology of MM CAF. In this study, we investigated the u-PA/u-PAR axis in MM-associated fibroblasts and explore additional mechanisms of tumor/stroma interplay in MM progression. METHODS: CAF were purified from total BM stromal fraction of 64 patients including monoclonal gammopathy of undetermined significance, asymptomatic and symptomatic MM, as well as MM in post-treatment remission. Flow cytometry, Real Time PCR and immunofluorescence were performed to investigate the u-PA/u-PAR system in relation to the level of activation of CAF at different stages of the disease. Moreover, proliferation and invasion assays coupled with silencing experiments were used to prove, at functional level, the function of u-PAR in CAF. RESULTS: We found higher activation level, along with increased expression of pro-invasive molecules, including u-PA, u-PAR and metalloproteinases, in CAF from patients with symptomatic MM compared to the others stages of the disease. Consistently, CAF from active MM as well as U266 cell line under the influence of medium conditioned by active MM CAF, display higher proliferative rate and invasion potential, which were significantly restrained by u-PAR gene expression inhibition. CONCLUSIONS: Our data suggest that the stimulation of u-PA/u-PAR system contributes to the activated phenotype and function of CAF during MM progression, providing a biological rationale for future targeted therapies against MM

Effects of blocking urokinase receptor signaling by antisense oligonucleotides in a mouse model of experimental prostate cancer bone metastases

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Who Feels Disadvantaged? Reporting Discrimination in Surveys

In this chapter, we seek to shed light on the mechanisms of perceived discrimination: Who, among recent immigrants, is more likely to feel discriminated against and report it when asked in a survey? Social scientists typically define discrimination as an observable and unjust difference in the treatment of distinct groups. To personally feel discriminated against, people must be aware of the differential treatment and perceive it as unjust. We show that reporting discrimination when asked in a survey depends substantially upon individual traits, including aspects that shape whether discrimination is accepted and whether immigrants feel attached to the host society. Although respondents report less discrimination if their job situation has improved after migration, people more likely report discrimination when they originate from countries in which the national legislature represents ethnic minority groups relatively well. Earlier difficulties related to the migration process and the lack of supporting networks continue to affect the perception of unfair treatment. Moreover, we show that individuals distinguish to a surprising degree between discrimination in and outside the work environment. For instance, when they are proficient in the local language, respondents often report discrimination in the workplace but not in a public environment. This distinction between discrimination in the workplace and discrimination in public also depends strongly upon the immigrant's origin. We conclude that contemporary individual-level measures and policy recommendations merely approximate discriminatory patterns; we urge future research to consider factors that affect individual perception of discrimination

Contemporary Surgery for Obstructive Sleep Apnea Syndrome

Surgical treatment of obstructive sleep apnea syndrome (OSAS) has been available in some form for greater than three decades. Early management for airway obstruction during sleep relied on tracheotomy which although life saving was not well accepted by patients. In the early eighties two new forms of treatment for OSAS were developed. Surgically a technique described as a uvulopalatopharyngoplasty (UPPP) was used to treat the retropalatal region for snoring and sleep apnea. Concurrently sleep medicine developed a nasal continuous positive airway pressure (CPAP) device to manage nocturnal airway obstruction. Both of these measures were used to expand and stabilize the pharyngeal airway space during sleep. The goal for each technique was to limit or alleviate OSAS. Almost 30 yr later these two treatment modalities continue to be the mainstay of contemporary treatment. As expected, CPAP device technology improved over time along with durable goods. Surgery followed suit and additional techniques were developed to treat soft and bony structures of the entire upper airway (nose, palate and tongue base). This review will only focus on the contemporary surgical methods that have demonstrated relatively consistent positive clinical outcomes. Not all surgical and medical treatment modalities are successful or even partially successful for every patient. Advances in the treatment of OSAS are hindered by the fact that the primary etiology is still unknown. However, both medicine and surgery continue to improve diagnostic and treatment methods. Methods of diagnosis as well as treatment regimens should always include both medical and surgical collaborations so the health and quality of life of our patients can best be served

The Response of the Prostate to Circulating Cholesterol: Activating Transcription Factor 3 (ATF3) as a Prominent Node in a Cholesterol-Sensing Network

Elevated circulating cholesterol is a systemic risk factor for cardiovascular disease and metabolic syndrome, however the manner in which the normal prostate responds to variations in cholesterol levels is poorly understood. In this study we addressed the molecular and cellular effects of elevated and suppressed levels of circulating cholesterol on the normal prostate. Integrated bioinformatic analysis was performed using DNA microarray data from two experimental formats: (1) ventral prostate from male mice with chronically elevated circulating cholesterol and (2) human prostate cells exposed acutely to cholesterol depletion. A cholesterol-sensitive gene expression network was constructed from these data and the transcription factor ATF3 was identified as a prominent node in the network. Validation experiments confirmed that elevated cholesterol reduced ATF3 expression and enhanced proliferation of prostate cells, while cholesterol depletion increased ATF3 levels and inhibited proliferation. Cholesterol reduction in vivo alleviated dense lymphomononuclear infiltrates in the periprostatic adipose tissue, which were closely associated with nerve tracts and blood vessels. These findings open new perspectives on the role of cholesterol in prostate health, and provide a novel role for ATF3, and associated proteins within a large signaling network, as a cholesterol-sensing mechanism

Mutations in Protein-Binding Hot-Spots on the Hub Protein Smad3 Differentially Affect Its Protein Interactions and Smad3-Regulated Gene Expression

Hub proteins are connected through binding interactions to many other proteins. Smad3, a mediator of signal transduction induced by transforming growth factor beta (TGF-β), serves as a hub protein for over 50 protein-protein interactions. Different cellular responses mediated by Smad3 are the product of cell-type and context dependent Smad3-nucleated protein complexes acting in concert. Our hypothesis is that perturbation of this spectrum of protein complexes by mutation of single protein-binding hot-spots on Smad3 will have distinct consequences on Smad3-mediated responses.We mutated 28 amino acids on the surface of the Smad3 MH2 domain and identified 22 Smad3 variants with reduced binding to subsets of 17 Smad3-binding proteins including Smad4, SARA, Ski, Smurf2 and SIP1. Mutations defective in binding to Smad4, e.g., D408H, or defective in nucleocytoplasmic shuttling, e.g., W406A, were compromised in modulating the expression levels of a Smad3-dependent reporter gene or six endogenous Smad3-responsive genes: Mmp9, IL11, Tnfaip6, Fermt1, Olfm2 and Wnt11. However, the Smad3 mutants Y226A, Y297A, W326A, K341A, and E267A had distinct differences on TGF-β signaling. For example, K341A and Y226A both reduced the Smad3-mediated activation of the reporter gene by ∼50% but K341A only reduced the TGF-β inducibilty of Olfm2 in contrast to Y226A which reduced the TGF-β inducibility of all six endogenous genes as severely as the W406A mutation. E267A had increased protein binding but reduced TGF-β inducibility because it caused higher basal levels of expression. Y297A had increased TGF-β inducibility because it caused lower Smad3-induced basal levels of gene expression.Mutations in protein binding hot-spots on Smad3 reduced the binding to different subsets of interacting proteins and caused a range of quantitative changes in the expression of genes induced by Smad3. This approach should be useful for unraveling which Smad3 protein complexes are critical for specific biological responses