Background-Systemic delivery of bone marrow-derived mesenchymal stem cells (BM-MSCs) is an attractive approach for myocardial repair. We aimed to test this strategy in a rat model after myocardial infarction (MI). Methods and Results-BM-MSCs were obtained from rat bone marrow, expanded in vitro to a purity of Ͼ50%, and labeled with 99m Tc exametazime, fluorescent dye, LacZ marker gene, or bromodeoxyuridine. Rats were subjected to MI by transient coronary artery occlusion or to sham MI.99m Tc-labeled cells (4ϫ10 6 ) were transfused into the left ventricular cavity of MI rats either at 2 or 10 to 14 days after MI and were compared with sham-MI rats or MI rats treated with intravenous infusion. Gamma camera imaging and isolated organ counting 4 hours after intravenous infusion revealed uptake of the 99m Tc-labeled cells mainly in the lungs, with significantly smaller amounts in the liver, heart, and spleen. Delivery by left ventricular cavity infusion resulted in drastically lower lung uptake, better uptake in the heart, and specifically higher uptake in infarcted compared with sham-MI hearts. Histological examination at 1 week after infusion identified labeled cells either in the infarcted or border zone but not in remote viable myocardium or sham-MI hearts. Labeled cells were also identified in the lung, liver, spleen, and bone marrow.

BackgroundPsoriasis is a complex disease at the cellular, genomic and genetic levels. The role of microRNAs in skin development was shown in a keratinocyte-specific Dicer knockout mouse model. Considering that two main characteristics of psoriasis are keratinocytes hyperproliferation and abnormal skin differentiation, we hypothesized that aberrant microRNA expression contributes to the psoriatic phenotype. Here, we describe the differential expression of miRNAs in psoriatic involved and uninvolved skin as compared to normal skin, revealing an additional aspect of this complex disorder.Methodology/Principal FindingsExpression arrays were used to compare microRNA expression in normal skin versus psoriatic involved and uninvolved skin. Fourteen differentially expressed microRNAs were identified, including hsa-miR-99a, hsa-miR-150, hsa-miR-423 and hsa-miR-197. The expression of these microRNAs was reevaluated by qPCR. IGF-1R, which is involved in skin development and the pathogenesis of psoriasis, is a predicted target of hsa-miR-99a. In an in situ hybridization assay, we found that IGF-1R and miR-99a are reciprocally expressed in the epidermis. Using a reporter assay, we found that IGF-1R is targeted by hsa-miR-99a. Moreover, over expression of miR-99a in primary keratinocytes down-regulates the expression of the endogenous IGF-1R protein. Over expression of miR-99a also inhibits keratinocyte proliferation and increases Keratin 10 expression. These findings suggest that overexpression of hsa-miR-99a in keratinocytes drives them towards differentiation. In primary keratinocytes grown in high Ca++, miR-99a expression increases over time. Finally, we found that IGF1 increases the expression of miR-99a.Conclusions/SignificanceWe identified several microRNAs that are expressed differentially in normal and psoriatic skin. One of these miRNAs is miR-99a that regulates the expression of IGF-1R. Moreover, miR-99a seems to play a role in the differentiation of keratinocytes. We suggest that miR-99a is one of the regulators of the IGF-1R signaling pathway in keratinocytes. Activation of IGF1 signaling results in elevation of miR-99a which represses the expression of IGF-1R.

It was previously shown that CEACAM1 on melanoma cells strongly predicts poor outcome. Here, we show a statistically significant increase of serum CEACAM1 in 64 active melanoma patients, as compared to 48 patients with no evidence of disease and 37 healthy donors. Among active patients, higher serum CEACAM1 correlated with LDH values and with decreased survival. Multivariate analysis with neutralization of LDH showed that increased serum CEACAM1 carries a hazard ratio of 2.40. In vitro, soluble CEACAM1 was derived from CEACAM1(+), but neither from CEACAM1(-) melanoma cells nor from CEACAM1(+) lymphocytes, and directly correlated with the number of CEACAM1(+) melanoma cells. Production of soluble CEACAM1 depended on intact de novo protein synthesis and secretion machineries, but not on metalloproteinase function. An unusually high percentage of CEACAM1(+) circulating NK and T lymphocytes was demonstrated in melanoma patients. CEACAM1 inhibited killing activity in functional assays. CEACAM1 expression could not be induced on lymphocytes by serum from patients with high CEACAM1 expression. Further, expression of other NK receptors was impaired, which collectively indicate on a general abnormality. In conclusion, the systemic dysregulation of CEACAM1 in melanoma patients further denotes the role of CEACAM1 in melanoma and may provide a basis for new tumor monitoring and prognostic platforms.

No abstract