Correction: Evaluation of tenascin-C by tenatumomab in T-cell non-Hodgkin lymphomas identifies a new target for radioimmunotherapy.

[This corrects the article DOI: 10.18632/oncotarget.23919.].

Evaluation of tenascin-C by tenatumomab in T-cell non-Hodgkin lymphomas identifies a new target for radioimmunotherapy.

The clinical outcome of T-cell non-Hodgkin lymphoma (NHL) is poor and innovative treatments are needed. Tenascin-C is a large extracellular glycoprotein not expressed under physiological conditions, but overexpressed in cancer. Aim of the study was to evaluate tenascin-C expression within pathologic tissue of T-cell NHL and determine its clinical significance. We used an immunohistochemistry approach using the anti-tenascin-C monoclonal antibody Tenatumomab in 75 systemic T-cell NHL (including 72 mature and 3 precursor T-cell NHL), and 25 primary cutaneous T-cell NHL. Data were analyzed in terms of staining intensity, proportion of involved areas and histologic pattern, and results were correlated with clinical characteristics and outcome. Ninety-three percent of the cases were tenascin-C positive and 59% of systemic diseases were characterized by a predominant involvement (>50%). Stromal expression was detected in all the cases while vascular and vascular plus cytoplasmic expression was present in 49% and 23%. The constant overexpression of the tenascin-C gene was observed in two independent publicly available T-cell NHL gene expression datasets. In conclusions, tenascin-C represents an attractive target that sets the rationale to investigate the therapeutic activity of radiolabeled Tenatumomab in T-cell NHL.

Intra-tumor AvidinOX allows efficacy of low dose systemic biotinylated Cetuximab in a model of head and neck cancer.

For locally advanced and metastatic head and neck squamous cell carcinoma (HNSCC), the current clinical use of Cetuximab in chemo/radiotherapy protocols is often associated to severe systemic toxicity. Here we report in vitro data in human FaDu pharynx SCC cells, showing that inactive concentrations of biotinylated Cetuximab (bCet) become active upon anchorage to AvidinOX on the surface of tumor cells. AvidinOX-anchored bCet induces apoptosis and DNA damage as well as specific inhibition of signaling, degradation and abrogation of nuclear translocation of EGFR. In the mouse model of FaDu cancer, we show that intra-tumor injection of AvidinOX allows anti-tumor activity of an otherwise inactive, intraperitoneally delivered, low dose bCet. Consistently with in vitro data, in vivo tumor inhibition is associated to induction of apoptosis, DNA damage and reduced angiogenesis. AvidinOX is under clinical investigation for delivering radioactive biotin to inoperable tumors (ClinicalTrials.gov NCT02053324) and present data support its use for the local treatment of HNSCC in combination with systemic administration of low dose bCet.

Radionuclide Therapy of Unresectable Tumors with AvidinOX and (90)Y-biotinDOTA: Tongue Cancer Paradigm.

Local treatment of unresectable tumors is challenging, particularly with radioactivity. Current practice relies on external beam irradiation or on a variety of medical devices for brachytherapy. Both approaches proved useful in controlling tumor growth, but are characterized by poor compliance of the patient, significant side-effects, high costs, and technological complexity, which hamper widespread use. The authors recently described a novel form of radionuclide therapy based on the oxidized form of avidin that, chemically reacting with tissue proteins, can secure radioactive biotin within the injected tissue, either when precomplexed or when taken from the blood stream after intravenous administration. AvidinOX-pretargeted (177)Lu-biotinDOTA ((177)Lu-ST2210) is currently under clinical investigation for the treatment of liver oligometastases from colorectal cancer (clinicaltrials.gov/NCT02053324). In the present work, the authors show that injected AvidinOX can link tissues of various natures such as prostate, kidney, breast, or brain and can react by contact with scraped tissues such as skin or urinary bladder. AvidinOX injected into human OSC19 tongue cancer masses orthotopically transplanted in nude mice takes up intravenously administered (90)Y-ST2210, which exerts significant antitumor activity, while preserving the integrity and functionality of the tongue. Present data confirm that AvidinOX-based radionuclide therapy is an innovative and promising approach for the local treatment of inoperable tumors.

Microcalcifications in breast cancer: an active phenomenon mediated by epithelial cells with mesenchymal characteristics.

BACKGROUND: Mammary microcalcifications have a crucial role in breast cancer detection, but the processes that induce their formation are unknown. Moreover, recent studies have described the occurrence of the epithelial-mesenchymal transition (EMT) in breast cancer, but its role is not defined. In this study, we hypothesized that epithelial cells acquire mesenchymal characteristics and become capable of producing breast microcalcifications. METHODS: Breast sample biopsies with microcalcifications underwent energy dispersive X-ray microanalysis to better define the elemental composition of the microcalcifications. Breast sample biopsies without microcalcifications were used as controls. The ultrastructural phenotype of breast cells near to calcium deposits was also investigated to verify EMT in relation to breast microcalcifications. The mesenchymal phenotype and tissue mineralization were studied by immunostaining for vimentin, BMP-2, ß2-microglobulin, ß-catenin and osteopontin (OPN). RESULTS: The complex formation of calcium hydroxyapatite was strictly associated with malignant lesions whereas calcium-oxalate is mainly reported in benign lesions. Notably, for the first time, we observed the presence of magnesium-substituted hydroxyapatite, which was frequently noted in breast cancer but never found in benign lesions. Morphological studies demonstrated that epithelial cells with mesenchymal characteristics were significantly increased in infiltrating carcinomas with microcalcifications and in cells with ultrastructural features typical of osteoblasts close to microcalcifications. These data were strengthened by the rate of cells expressing molecules typically involved during physiological mineralization (i.e. BMP-2, OPN) that discriminated infiltrating carcinomas with microcalcifications from those without microcalcifications. CONCLUSIONS: We found significant differences in the elemental composition of calcifications between benign and malignant lesions. Observations of cell phenotype led us to hypothesize that under specific stimuli, mammary cells, which despite retaining a minimal epithelial phenotype (confirmed by cytokeratin expression), may acquire some mesenchymal characteristics transforming themselves into cells with an osteoblast-like phenotype, and are able to contribute to the production of breast microcalcifications.

Transglutaminase 2 as a biomarker of osteoarthritis: an update.

Osteoarthritis is a progressive joint disease characterized by cartilage degradation and bone remodelling. Under physiologic conditions, articular cartilage displays a stable chondrocyte phenotype, whereas in osteoarthritis a chondrocyte hypertrophy develops near the sites of cartilage surface damage and associates to the pathologic expression of type X collagen. Transglutaminases (TGs) include a family of Ca(2+)-dependent enzymes that catalyze the formation of γ-glutamyl cross-links. Their substrates include a variety of intracellular and extracellular macromolecular components. TGs are ubiquitously and abundantly expressed and implicated in a variety of physiopathological processes. TGs activity is modulated by inflammatory cytokines. TG2 (also known as tissue transglutaminase) mediates the hypertrophic differentiation of joint chondrocytes and interleukin-1-induced calcification. Histomorphometrical and biomolecular investigations document increased TG2 expression in human and experimental osteoarthritis. Consequently, the level of TG2 expression may represent an adjuvant additional marker to monitor tissue remodelling occurring in osteoarthritic joint tissue. Experimental induction of osteoarthritis in TG2 knockout mice is followed from reduced cartilage destruction and increased osteophyte formation compared to wild-type mice, suggesting a different influence on joint bone and cartilage remodelling. The capacity of transamidation by TG2 to regulate activation of latent TGF-ß seems to have a potential impact on the regulation of inflammatory response in osteoarthritic tissues. Additional studies are needed to define TG2-regulated pathways that are differently modulated in osteoblasts and chondrocytes during osteoarthritis.

miR-24 triggers epidermal differentiation by controlling actin adhesion and cell migration.

During keratinocyte differentiation and stratification, cells undergo extensive remodeling of their actin cytoskeleton, which is important to control cell mobility and to coordinate and stabilize adhesive structures necessary for functional epithelia. Limited knowledge exists on how the actin cytoskeleton is remodeled in epithelial stratification and whether cell shape is a key determinant to trigger terminal differentiation. In this paper, using human keratinocytes and mouse epidermis as models, we implicate miR-24 in actin adhesion dynamics and demonstrate that miR-24 directly controls actin cable formation and cell mobility. miR-24 overexpression in proliferating cells was sufficient to trigger keratinocyte differentiation both in vitro and in vivo and directly repressed cytoskeletal modulators (PAK4, Tks5, and ArhGAP19). Silencing of these targets recapitulated the effects of miR-24 overexpression. Our results uncover a new regulatory pathway involving a differentiation-promoting microribonucleic acid that regulates actin adhesion dynamics in human and mouse epidermis.

Age-related increase of stem marker expression influences vascular smooth muscle cell properties.

OBJECTIVE: Aging represents a major risk factor for vascular disease development. With aging, changes of the biological properties of vascular smooth muscle cells (SMCs) are observed. Stem marker expression characterizes SMCs during developmental growth and atherosclerosis, but the contribution of SMCs with stem features to the age-related arterial remodeling remains largely unknown. METHODS AND RESULTS: Immunostaining revealed rare vascular growth factor receptor-1(+) (flt-1(+)) and c-kit(+) cells in tunica media of grossly normal human young (17-30 years old) large arteries and 2-month old rat aorta, whereas CD133(+) cells were absent. In large arteries of human aged donors (64-77 years), flt-1(+) and c-kit(+) cell number increased in the intimal thickening and tunica media. Double immunofluorescence revealed that 30.6 ± 3% of flt-1(+) intimal cells co-expressed α-smooth muscle actin. Immunostaining, blots and RT-PCR documented the increased expression of flt-1 and c-kit in 20-24-month old rat aortic media. In vitro, old rat aortic SMCs proliferated and migrated more with greater flt-1, c-kit, NF-κB, VCAM-1, IAP-1 and MCP-1 levels and less α-smooth muscle actin and myosin compared to young SMCs. Old SMCs were also more susceptible to all-trans retinoic and NF-κB inhibition-induced apoptosis compared to young SMCs. Anti-flt-1 blocking antibody reduced migration and placental growth factor-induced but not serum and PDGF-BB-stimulated proliferation of old SMCs. CONCLUSIONS: The increase of flt-1(+) and c-kit(+) SMCs characterizes large arteries of aged donors; the blocking of flt-1 signaling influences the behavior of old SMCs, suggesting that the accumulation of SMCs with a stem phenotype contributes to the age-dependent adverse arterial remodeling.

Asymptomatic carotid plaque rupture with unexpected thrombosis over a non-canonical vulnerable lesion.

OBJECTIVE: Several studies have demonstrated that carotid plaque rupture and thrombosis represent the most important factors correlated with the onset of acute cerebrovascular symptoms. Nevertheless, ruptured thrombotic plaques have been described also in asymptomatic patients. What still needs to be clarified is why a plaque rupture leads either to an acute ischemic syndrome or, in a minor group of patients, remains asymptomatic. The purpose of this study was to systematically compare the histologic features of thrombotic plaques both in asymptomatic and symptomatic patients in order to identify specific findings that could explain the peculiar clinical behavior that characterizes each of the clinical settings. METHODS: A total of 157 thrombotic plaques from 60 asymptomatic patients and 97 with major stroke who consecutively underwent CEA were serially sectioned and studied by histology. RESULTS: A minute cap disruption very frequently characterizes thrombotic plaques of asymptomatic patients and it was always smaller than large ulcers observed in thrombotic symptomatic plaques (651 ± 687µm vs. 4150 ± 3526, p=0.001). In asymptomatics this typical feature was associated with fewer inflammatory cells (20.1 ± 8.8 vs. 33.9 ± 26.1 cells × hpf, p=0.001), smaller lipidic-necrotic core (33.9%± 2.9% vs. 42.0% ± 2.4%; p=0.04) and larger calcification (16.2 ± 12.8% vs. 8.1 ± 12.2%, p=0.02). Symptomatic patients with thrombotic plaques showed higher incidence of metabolic syndrome (p=0.002) and moderate-high Framingham risk scores (p=0.001) comparing to asymptomatic individuals. CONCLUSION: The transformation from a stable to a vulnerable plaque is a gradual process in the natural history of the disease and plaque rupture is an event not necessarily occurring at a late phase but also at earlier one. In this case, the rupture will be most likely smaller and clinically asymptomatic.

TRAIN: Training through Research Application Italian iNitiative.

Training through Research Application Italian iNitiative (TRAIN) is a mobility program financed under the EU action called "Cofinancing of regional, national and international programs" (COFUND) of the European Commission Seventh Framework Program (FP7) - People, and has been designed to encourage the promotion and development of international programs of research through mobility at various stages of research careers. The aim of TRAIN is to improve translational skills in the field of cancer by promoting a three-year international mobility program assigning a total of 51 fellowships subdivided into incoming, outgoing and reintegration fellowships.?The TRAIN proposal has been submitted in February 2009 to the European Commission in reply to the 2008 FP7-PEOPLE-COFUND call and has been successfully evaluated. TRAIN is addressed to postdoctoral scientists or scientists who have at least four years' full-time equivalent research experience and who wish to improve their careers spending one year abroad. The mobility program is open also to non-Italian experienced scientists wishing to spend one year in an Italian research center or private company. Part of the scheme is targeted to experienced Italian scientists who have completed at least three years of research in a foreign country and are interested in returning to Italy.?TRAIN is part of an overall Italian strategy outlined by the International Program of the Italian Cancer Network "Alleanza Contro il Cancro" to promote Italian participation in the building of the European Area for translational cancer research and to enhance the interaction between academy and industry.

Difficulty diagnosing chronic cryptococcal meningitis in idiopathic CD4+ lymphocytopenia.

A 64-year-old man with idiopathic CD4(+) lymphocytopenia developed cognitive impairment and gait ataxia with isolated obstructive hydrocephalus, which was fatal. Cerebrospinal fluid showed mild pleocytosis, but the etiology was not revealed by extensive analysis. At autopsy, inflammatory cells, CD8(+) lymphocytes and abundant macrophages but not CD4(+) lymphocytes were infiltrating the meninges at the base of the brain. Electron microscopy demonstrated that inflammation was caused by Cryptococcus neoformans, which was localized exclusively within macrophages, where it grew with budding. Our study suggests that, in idiopathic CD4(+) lymphocytopenia, macrophages can efficiently phagocytize but inefficiently digest C. neoformans, thus representing a vehicle of chronic intracellular infection.

Propionyl-L-carnitine improves postischemic blood flow recovery and arteriogenetic revascularization and reduces endothelial NADPH-oxidase 4-mediated superoxide production.

OBJECTIVE: The beneficial effect of the natural compound propionyl-l-carnitine (PLC) on intermittent claudication in patients with peripheral arterial disease is attributed to its anaplerotic function in ischemic tissues, but inadequate information is available concerning action on the vasculature. METHODS AND RESULTS: We investigated the effects of PLC in rabbit hind limb collateral vessels after femoral artery excision, mouse dorsal air pouch, chicken chorioallantoic membrane, and vascular cells by angiographic, Doppler flow, and histomorphometrical and biomolecular analyses. PLC injection accelerated hind limb blood flow recovery after 4 days (P<0.05) and increased angiographic quadriceps collateral vascularization after 7 days (P<0.001) Histomorphometry confirmed the increased vascular area (P<0.05), with unchanged intramuscular capillary density. PLC-induced dilatative adaptation, and growth was found associated with increased inducible nitric oxide synthase and reduced arterial vascular endothelial growth factor and intracellular adhesion molecule-1 expression. PLC also increased vascularization in air pouch and chorioallantoic membrane (P<0.05), particularly in large vessels. PLC increased endothelial and human umbilical vascular endothelial cell proliferation and rapidly reduced inducible nitric oxide synthase and NADPH-oxidase 4-mediated reactive oxygen species production in human umbilical vascular endothelial cells; NADPH-oxidase 4 also regulated NF-kappaB-independent intracellular adhesion molecule-1 expression. CONCLUSIONS: Our results provided strong evidence that PLC improves postischemic flow recovery and revascularization and reduces endothelial NADPH-oxidase-related superoxide production. We recommend that PLC should be included among therapeutic interventions that target endothelial function.

Flt-1 expression influences apoptotic susceptibility of vascular smooth muscle cells through the NF-kappaB/IAP-1 pathway.

AIMS: Flt-1 is an fms-like tyrosine kinase receptor which binds to vascular endothelial growth factor (VEGF) and placental growth factor (PlGF). Ligand activation and blocking of flt-1 influence several vascular smooth muscle cell (SMC) functions, including apoptotic susceptibility. However, downstream signal transduction pathways by which flt-1 regulates SMC apoptosis have still to be investigated. METHODS AND RESULTS: Flt-1 expression and apoptosis in Wistar rat aortic intimal cells 15 days after ballooning were studied by immunohistochemistry, cytometry, cell sorting, western blotting, and PCR. Anti-flt1 blocking antibody effects were compared with those of anti-PlGF and anti-VEGF antibodies. Rat aortic intimal cells 15 days after injury exhibited increased flt-1 protein and mRNA and lower smooth muscle markers compared with normal media SMCs. Immunoreactivity for flt-1 protein was also observed in apoptotic intimal cells. Anti-flt-1 (EC(50) = 16.5 ng/mL) and anti-PlGF (EC(50) = 20.5 ng/mL) antibodies added to intimal cultures reduced serum-deprived apoptosis but not serum- and PDGF-BB-induced proliferation; the anti-VEGF antibody was ineffective. Sorted flt-1(+) cells were more clonogenic than flt-1(-) and whole intimal SMC populations. Increased nuclear factor-kappaB (NF-kappaB) and inhibitor of apoptosis protein-1 (IAP-1) and reduced bax levels associated with the anti-flt-1-induced increase of intimal SMC survival; the latter was prevented by NF-kappaB activity inhibitor and IAP-1 interfering RNA (RNAi). Blocking of NF-kappaB activity reduced IAP-1 expression and prevented IAP-1 RNAi effects. Increased flt-1 immunoreaction was also documented in human atheromatous lesions. CONCLUSION: Our results show that anti-flt-1 blocking reduces apoptosis through NF-kappaB and the downstream IAP-1 pathway. The close link between flt-1, PlGF, and apoptotic susceptibility of intimal SMCs suggests new potential strategies aimed at influencing post-injury arterial remodelling.

Alpha actin isoforms expression in human and rat adult cardiac conduction system.

In the adult heart, cardiac muscle comprises the working myocardium and the conduction system (CS). The latter includes the sinoatrial node (SAN), the internodal tract or bundle (IB), the atrioventricular node (AVN), the atrioventricular bundle (AVB), the bundle branches (BB) and the peripheral Purkinje fibers (PF). Most of the information concerning the phenotypic features of CS tissue derives from the characterization of avian and rodent developing hearts; data concerning the expression of actin isoforms in adult CS cardiomyocytes are scarce. Using specific antibodies, we investigated the distribution of alpha-skeletal (alpha-SKA), alpha-cardiac (alpha-CA), alpha-smooth muscle (alpha-SMA) actin isoforms and other muscle-typical proteins in the CS of human and rat hearts at different ages. SAN and IB cardiomyocytes were characterized by the presence of alpha-SMA, alpha-CA, calponin and caldesmon, whereas alpha-SKA and vimentin were absent. Double immunofluorescence demonstrated the co-localisation of alpha-SMA and alpha-CA in I-bands of SAN cardiomyocytes. AVN, AVB, BB and PF cardiomyocytes were alpha-SMA, calponin, caldesmon and vimentin negative, and alpha-CA and alpha-SKA positive. No substantial differences in actin isoform distribution were observed in human and rat hearts, except for the presence of isolated subendocardial alpha-SMA positive cardiomyocytes co-expressing alpha-CA in the ventricular septum of the rat. Aging did not influence CS cardiomyocyte actin isoform expression profile. These findings support the concept that cardiomyocytes of SAN retain the phenotype of a developing myogenic cell throughout the entire life span.

Application of platelet-rich plasma in plastic surgery: clinical and in vitro evaluation.

The clinical use of platelet-rich plasma (PRP) for a wide variety of application has been reportedly employed most prevalently in problematic wounds, maxillofacial and hemi-facial atrophy, Romberg Syndrome, and diabetic foot ulcers. To our knowledge, PRP has never been described in the enhancement of fat grafting during tissue-engineering application in vivo. The authors describe the preparation of PRP and its use in a series of 43 patients who underwent plastic, reconstructive, and maxillofacial surgery for chronic lower extremity ulcers (n = 18) and multiple facial applications (n = 25). PRP mixed with fat grafting was used in 76% patients affected by multiple facial diseases and in 88.9% patients affected by lower extremity ulcers. PRP injection alone was used in the remaining patients. The authors observed that after a 7.1-week and 9.7-week (average) course of twice-daily wound treatment with PRP suspended on a collagen base, 61.1% and 88.9% of chronic lower extremity ulcers underwent to 100% reepithelization compared with 40% and 60% of controls (n = 10) treated with hyaluronic acid and collagen medication. In patients treated with reconstructing three-dimensional projection of face by fat grafting and PRP, we observed a 70% maintenance of contour restoring and three-dimensional volume after 1 year compared to only 31% of controls (n = 10) treated with fat grafting alone. In vitro, PRP induced a significant increase in the number of adipose-tissue-derived stem cells compared to control cultures. These results documented that PRP accelerates chronic skin ulcer reepithelization and improves maintenance and function of fat graft in patients who underwent plastic reconstructive surgery, possibly by stimulating adipose-tissue-derived stem cell proliferation.

Relation between animal-type melanoma and reduced nuclear expression of glutathione S-transferase pi.

BACKGROUND: Animal-type melanoma (ATM) is a rare variant of the tumor showing diffuse, heavily pigmented neoplastic cells in the dermis. Despite the high mean thickness of the lesions, reports seem to indicate a less aggressive behavior and a better survival rate for ATM compared with conventional melanoma, but the underlying pathways related to this favorable outcome are still unknown. OBSERVATIONS: Five women and 2 men aged 20 to 92 years presented with pigmented skin nodules (n = 5) or plaques (n = 2), varying in size from 1.0 to 4.5 cm. Findings from microscopic examination showed monotypic-appearing melanocytes with abundant intracytoplasmic melanin in a nodular or fascicular arrangement (mean Breslow thickness, 4.97 mm). Immunohistochemical analysis of ATM cells demonstrated the typical positive staining for S-100, vimentin, HMB-45, and melan-A. The investigation of the pi isoform of glutathione S-transferase, a family of enzymes involved in tumor progression, revealed that nuclear expression is reduced in ATMs compared with control melanomas, whereas results from cytoplasmic staining did not vary. One patient died of cardiac failure without evidence of disease progression; the remaining patients are disease-free at 3 (n = 4) and 5 years (n = 3). CONCLUSIONS: Our findings confirm that ATM is a variant of melanoma with distinctive clinical and histological features. Low nuclear expression of glutathione S-transferase pi expression is a characteristic of ATM and could add new insight to better understand the unusual biological behavior of this rare neoplasm.

Stem cell marker expression and proliferation and apoptosis of vascular smooth muscle cells.

Vascular endothelial Flt-1 and other stem cell markers are variably expressed in vascular smooth muscle cells (SMCs) during normal and pathological conditions, but their biological role remains uncertain. In normal rat aorta, rare flt-1+ and c-kit+ SMCs were detected. Fifteen days after injury, 61.8 +/- 3.8, 45.7 +/- 3% of the intimal cells resulted flt-1+ and c-kit+ and expressed low level of alpha-smooth muscle actin; CD133+ cells were 5.6 +/- 0.7%. BrDU+/flt-1+ largely predominated in the neointima, whereas BrDU+/CD133+ cells were rare. Forty-five and sixty days after injury, intimal proliferation such as BrDU+ cells was greatly reduced. After sixty days, intimal stem marker expression had almost disappeared whereas alpha-smooth muscle actin was restored. Flk-1 and Oct-4 SMC immunodection was consistently negative. In vitro, intimal cells obtained fifteen days after injury exhibited an epithelioid phenotype and increased flt-1 and c-kit protein and mRNA and low smooth muscle markers compared to spindle-shaped medial and intimal SMCs obtained after sixty days. Epithelioid clones, independently from layer of origin, were similar in stem cell marker expression. The anti-flt-1 blocking antibody added to epithelioid SMC cultures reduced serum-deprived apoptosis and migration but not PDGF-BB-induced proliferation, and increased cell-populated collagen lattice contraction. In conclusion, vascular SMC stem marker expression was variable, chronologically modulated and prevalent in epithelioid populations and clones; among stem markers, flt-1 expression critically regulates intimal SMC response to microenviromental changes.

The inhibition of the highly expressed miR-221 and miR-222 impairs the growth of prostate carcinoma xenografts in mice.

BACKGROUND: MiR-221 and miR-222 are two highly homologous microRNAs whose upregulation has been recently described in several types of human tumors, for some of which their oncogenic role was explained by the discovery of their target p27, a key cell cycle regulator. We previously showed this regulatory relationship in prostate carcinoma cell lines in vitro, underlying the role of miR-221/222 as inducers of proliferation and tumorigenicity. METHODOLOGY/PRINCIPAL FINDINGS: Here we describe a number of in vivo approaches confirming our previous data. The ectopic overexpression of miR-221 is able, per se, to confer a high growth advantage to LNCaP-derived tumors in SCID mice. Consistently, the anti-miR-221/222 antagomir treatment of established subcutaneous tumors derived from the highly aggressive PC3 cell line, naturally expressing high levels of miR-221/222, reduces tumor growth by increasing intratumoral p27 amount; this effect is long lasting, as it is detectable as long as 25 days after the treatment. Furthermore, we provide evidence in favour of a clinical relevance of the role of miR-221/222 in prostate carcinoma, by showing their general upregulation in patient-derived primary cell lines, where we find a significant inverse correlation with p27 expression. CONCLUSIONS/SIGNIFICANCE: These findings suggest that modulating miR-221/222 levels may have a therapeutic potential in prostate carcinoma.

High-resolution multicontrast-weighted MR imaging from human carotid endarterectomy specimens to assess carotid plaque components.

The American Heart Association modified classification for atherosclerotic plaque lesions has defined vulnerable plaques as those prone to rupture. The aim of our study was to assess the sensitivity and specificity of 1.5-T magnetic resonance imaging (MRI) in the evaluation of the characteristics of plaque components. Twelve carotid endarterectomy specimens were imaged by ex-vivo high-resolution 1.5-T MRI. Thirty-four cross-section axial images were selected for pixel-by-pixel basis analysis to demonstrate the most significant tissue features. Data were then submitted for histopathological examination and each specimen analysed in the light of the histological components (lipid core, fibrous tissue, fibrous/loose connective tissue, calcifications). The overall sensitivity and specificity rates for each tissue type were, respectively, 92% and 74% for the lipid core, 82% and 94% for the fibrous tissue, 72% and 87% for the fibrous/loose connective tissue, and 98% and 99% for calcification. The use of 1.5-T MRI appears to be a reliable tool to characterise plaque components and could help in the screening of patients with high risk of plaque rupture. The possibility of applying MRI in clinical daily practice may change the non-invasive approach to carotid artery diagnostic imaging, thus allowing an early identification of patients with vulnerable plaques.