Deregulation of MicroRNAs mediated control of carnitine cycle in prostate cancer: molecular basis and pathophysiological consequences.

Cancer cells reprogram their metabolism to maintain both viability and uncontrolled proliferation. Although an interplay between the genetic, epigenetic and metabolic rewiring in cancer is beginning to emerge, it remains unclear how this metabolic plasticity occurs. Here, we report that in prostate cancer cells (PCCs) microRNAs (miRNAs) greatly contribute to deregulation of mitochondrial fatty acid (FA) oxidation via carnitine system modulation. We provide evidence that the downregulation of hsa-miR-124-3p, hsa-miR-129-5p and hsa-miR-378 induced an increase in both expression and activity of CPT1A, CACT and CrAT in malignant prostate cells. Moreover, the analysis of human prostate cancer and prostate control specimens confirmed the aberrant expression of miR-124-3p, miR-129-5p and miR-378 in primary tumors. Forced expression of the miRNAs mentioned above affected tumorigenic properties, such as proliferation, migration and invasion, in PC3 and LNCaP cells regardless of their hormone sensitivity. CPT1A, CACT and CrAT overexpression allow PCCs to be more prone on FA utilization than normal prostate cells, also in the presence of high pyruvate concentration. Finally, the simultaneous increase of CPT1A, CACT and CrAT is fundamental for PCCs to sustain FA oxidation in the presence of heavy lipid load on prostate cancer mitochondria. Indeed, the downregulation of only one of these proteins reduces PCCs metabolic flexibility with the accumulation of FA-intermediate metabolites in the mitochondria. Together, our data implicate carnitine cycle as a primary regulator of adaptive metabolic reprogramming in PCCs and suggest new potential druggable pathways for prevention and treatment of prostate cancer.

Hyperspectral Raman imaging of human prostatic cells: An attempt to differentiate normal and malignant cell lines by univariate and multivariate data analysis.

Hyperspectral Raman images of human prostatic cells have been collected and analysed with several approaches to reveal differences among normal and tumor cell lines. The objective of the study was to test the potential of different chemometric methods in providing diagnostic responses. We focused our analysis on the ν(CH) region (2800-3100cm-1) owing to its optimal Signal-to-Noise ratio and because the main differences between the spectra of the two cell lines were observed in this frequency range. Multivariate analysis identified two principal components, which were positively recognized as due to the protein and the lipid fractions, respectively. The tumor cells exhibited a modified distribution of the cytoplasmatic lipid fraction (mainly localized alongside the cell boundary) which may result very useful for a preliminary screening. Principal Component analysis was found to provide high contrast and to be well suited for image-processing purposes. Self-Modelling Curve Resolution made available meaningful spectra and relative-concentration values; it revealed a 97% increase of the lipid fraction in the tumor cell with respect to the control. Finally, a univariate approach confirmed significant and reproducible differences between normal and tumor cells.

Long-Term Fluoride Release from Dental Resins Affects STRO-1+ Cell Behavior.

Fluoride-releasing restorative dental materials can be beneficial to remineralize dentin and help prevent secondary caries. However, the effects of fluoride release from dental materials on the activity of dental pulp stem cells are not known. Here we investigate whether different fluoride release kinetics from dental resins supplemented with modified hydrotalcite (RK-F10) or fluoride-glass filler (RK-FG10) could influence the behavior of a human dental pulp stem cell subpopulation (STRO-1(+) cells) known for its ability to differentiate toward an odontoblast-like phenotype. The 2 resins, characterized by similar physicochemical properties and fluoride content, exhibited different long-term fluoride release kinetics. Our data demonstrate that long-term exposure of STRO-1(+) cells to a continuous release of a low amount of fluoride by RK-F10 increases their migratory response to transforming growth factor ß1 (TGF-ß1) and stromal cell-derived factor 1 (SDF-1), both important promoters of pulp stem cell recruitment. Moreover, the expression patterns of dentin sialoprotein (dspp), dentin matrix protein 1 (dmp1), osteocalcin (ocn), and matrix extracellular phosphoglycoprotein (mepe) indicate a complete odontoblast-like cell differentiation only when STRO-1(+) cells were cultured on RK-F10. On the contrary, RK-FG10, characterized by an initial fluoride release burst and reduced lifetime of the delivery, did not elicit any significant effect on both STRO-1(+) cell migration and differentiation. Taken together, our results highlight the importance of taking into account fluoride release kinetics in addition to fluoride concentration when designing new fluoride-restorative materials.

Efficient cultivation of neural stem cells with controlled delivery of FGF-2.

Neural stem cells (NSCs) raised the hope for cell-based therapies in human neurodevelopmental and neurodegenerative diseases. Current research strategies aim to isolate, enrich, and propagate homogeneous populations of neural stem cells. Unfortunately, several concerns with NSC cultures currently may limit their therapeutic promise. Exhaustion of growth factors and/or their uncontrolled release with burst and fall in their concentration may greatly affect the in vitro behavior of NSCs. In this context, we investigate whether a device containing heparan sulfate (HS), which is a co-factor in growth factor-mediated cell proliferation and differentiation, could potentiate and prolong the delivery of fibroblast growth factor-2 (FGF-2) and thus improve in vitro NSC cultivation. We demonstrated that NSCs cultivated in media with a controlled release of FGF-2 from a polyelectrolyte polymer showed a higher proliferation rate, and reduced apoptosis and senescence. In these experimental conditions NSCs preserve their stemness properties for a longer period of time compared with controls. Also of interest is that cell fate properties are conserved as well. The controlled release of FGF-2 reduced the level of oxidative stress and this is associated with a lower level of damaged DNA. This result may explain the reduced level of senescence and apoptosis in NSCs cultivated in the presence of hydrogel-releasing FGF-2.

[Androgen-deprivation therapy in prostate cancer: clinical evidence and future perspectives]. / La deprivazione androgenica nel carcinoma prostatico: evidenze cliniche e prospettive future.

Androgens are involved in the development and progression of prostate cancer even if the mechanism is not well-recognized. For this reason androgen-deprivation therapy remains a milestone for the treatment of patients with advanced and metastatic disease and, in the last years, in conjunction with radiotherapy and surgery in locally advanced tumors. Alternative options, such as intermittent deprivation suppression, seem to be promising in terms of clinical benefits and toxicity profile. However, current therapies present side effects, such as testosterone surge with consequent clinical flare-up, metabolic syndrome and hormone-resistance, which develops after a variable number of years. Novel therapies such as LH-RH antagonists and prolonged depot LH-RH analogues have been developed in order to avoid clinical flare-up and testosterone microsurges. Novel androgen synthesis inhibitors, such as abiraterone acetate and MDV3100, have been recently discovered and tested as promising hormonal second-line agents in patients with castration-resistant prostate cancer. Finally, long-term side effects from androgen deprivation, such as osteoporosis, sarcopenic obesity and cardiovascular morbidity should be carefully monitored and properly treated.

[Doping and urologic tumors]. / Doping e neoplasie urologiche.

Several substances such as growth hormone (GH), erythropoietin (Epo), and anabolic steroids (AS) are improperly utilized to increase the performance of athletes. Evaluating the potential cancer risk associated with doping agents is difficult since these drugs are often used at very high doses and in combination with other licit or illicit drugs. The GH, via its mediator, the insulin-like growth factor 1 (IGF-1), is involved in the development and progression of cancer. Animal studies suggested that high levels of GH/IGF-1 increase progression of androgen-independent prostate cancer. Clinical data regarding prostate cancer are mostly based on epidemiological studies or indirect data such as IGF-1 high levels in patients with prostate cancer. Even if experimental studies showed a correlation between Epo and cancer, no clinical data are currently available on cancer development related to Epo as a doping agent. Androgens are involved in prostate carcinogenesis modulating genes that regulate cell proliferation, apoptosis and angiogenesis. Most information on AS is anecdotal (case reports on prostate, kidney and testicular cancers). Prospective epidemiologic studies failed to support the hypothesis that circulating androgens are positively associated with prostate cancer risk. Currently, clinical and epidemiological studies supporting association between doping and urological neoplasias are not available. Nowadays, exposure to doping agents starts more prematurely with a consequent longer exposition period; drugs are often used at very high doses and in combination with other licit or illicit drugs. Due to all these elements it is impossible to predict all the side effects, including cancer; more detailed studies are therefore necessary.

Behaviour of human mesenchymal stem cells on a polyelectrolyte-modified HEMA hydrogel for silk-based ligament tissue engineering.

The aim of this study was to design a functional bio-engineered material to be used as scaffold for autologous mesenchymal stem cells in ligament tissue engineering. Polyelectrolyte modified HEMA hydrogel (HEMA-co-METAC), applied as coating on silk fibroin fibres, has been formulated in order to take advantage of the biocompatibility of the polyelectrolyte by increasing its mechanical properties with silk fibres. Human bone marrow mesenchymal stem cells behaviour on such reinforced polyelectrolyte has been studied by evaluating cell morphology, cell number, attachment, spreading and proliferation together with collagen matrix production and its mRNA expression. Silk fibroin fibres matrices with HEMA-co-METAC coating exhibited acceptable mechanical behaviour compared to the natural ligament, good human mesenchymal stem cell adhesion and with mRNA expression studies higher levels of collagen types I and III expression when compared to control cells on polystyrene. These data indicate high expression of mRNA for proteins responsible for the functional characteristics of the ligaments and suggest a potential for use of this biomaterial in ligament tissue-engineering applications.

[Regenerative medicine: applications and development in urology].

PURPOSE. Congenital abnormalities and acquired disorders can lead to organ damage and loss. Nowadays, transplantation represents the only effective treatment option. However, there is a marked decrease in the number of organ donors, which is even yearly worsening due to the population aging. The regenerative medicine represents a realistic option that allows to restore and maintain the normal functions of tissues and organs. This article reviews the principles of regenerative medicine and the recent advances with regard to its application to the genitourinary tract. RECENT FINDINGS. The field of regenerative medicine involves different areas of technology, such as tissue engineering, stem cells and cloning. Tissue engineering involves the field of cell transplantation, materials science and engineering in order to create functional replacement tissues. Stem cells and cloning permit the extraction of pluripotent, embryonic stem cells offering a potentially limitless source of cells for tissue engineering applications. Most current strategies for tissue engineering depend upon a sample of autologous cells from the patient's diseased organ. Biopsies from patients with extensive end-stage organ failure, however, may not yield enough normal cells. In these situations, stem cells are envisaged as being an alternative source. Stem cells can be derived from discarded human embryos (human embryonic stem cells), from fetal tissue or from adult sources (bone marrow, fat, skin). Therapeutic cloning offers a potentially limitless source of cells for tissue engineering applications. Regenerative medicine and tissue engineering scientists have increasingly applied the principles of cell transplantation, materials science and bioengineering to construct biological substitutes that will restore and maintain normal function in urological diseased and injured tissues such as kidney, ureter, bladder, urethra and penis. CONCLUSIONS. Regenerative medicine offers several applications in acquired and congenital genito-urinary diseases. Tissue engineering, stem cells and, mostly, cloning have been applied in experimental studies with excellent results. Few preliminary human applications have been developed with promising results.

Incidence of prostate cancer in Sicily: results of a multicenter case-findings protocol.

OBJECTIVE: To establish the incidence of prostate cancer (PCa) in Sicily in patients who entered an early detection protocol. METHODS: From February 2002 to February 2004, 16,298 subjects aged 40-75 entered the protocol. Patients with suspicious DRE, PSA>10 ng/ml, PSA

tBid induces alterations of mitochondrial fatty acid oxidation flux by malonyl-CoA-independent inhibition of carnitine palmitoyltransferase-1.

Recent studies suggest a close relationship between cell metabolism and apoptosis. We have evaluated changes in lipid metabolism on permeabilized hepatocytes treated with truncated Bid (tBid) in the presence of caspase inhibitors and exogenous cytochrome c. The measurement of beta-oxidation flux by labeled palmitate demonstrates that tBid inhibits beta-oxidation, thereby resulting in the accumulation of palmitoyl-coenzyme A (CoA) and depletion of acetyl-carnitine and acylcarnitines, which is pathognomonic for inhibition of carnitine palmitoyltransferase-1 (CPT-1). We also show that tBid decreases CPT-1 activity by a mechanism independent of both malonyl-CoA, the key inhibitory molecule of CPT-1, and Bak and/or Bax, but dependent on cardiolipin decrease. Overexpression of Bcl-2, which is able to interact with CPT-1, counteracts the effects exerted by tBid on beta-oxidation. The unexpected role of tBid in the regulation of lipid beta-oxidation suggests a model in which tBid-induced metabolic decline leads to the accumulation of toxic lipid metabolites such as palmitoyl-CoA, which might become participants in the apoptotic pathway.

Endoprosthesis implantation in the treatment of recurrent urethral stricture: a multicenter study. Sicilian-Calabrian Urology Society.

PURPOSE: This study was conducted by nine urology departments in southern Italy to assess the efficacy of and tolerance to treatment of recurrent urethral stricture using a permanent prosthesis. PATIENTS AND METHODS: Since 1992, 99 prostheses have been implanted to treat inflammatory and iatrogenic (seven departments) or all types (two departments) of urethral strictures. The Urolume Wallstent was used in 94 cases. Three centers implanted more than one prosthesis when this was indicated. Local anesthesia was used by six centers, spinal anesthesia by two, and local or general by one. At three centers, urethrotomy was performed immediately prior to implantation; two centers used dilation to 30F, and two centers performed urethrotomy 24 or 36 hours before implantation. The median follow-up is 29.1 months (range 3-53 months). RESULTS: The results were good in 52%, fair in 34%, and poor in 14% of patients. The maximum flow rate increased >75% in 82% of patients. All departments reported complete reepithelialization of the urethra by 6 months. The short-term complications (7-28 days) were perineal discomfort (86%) and dribbling (14%). The long-term complications were painful erection (44%), mucous hyperplasia (44%), recurring stricture (29%), and incontinence (14%). All departments performed resection for hyperplasia in many cases. CONCLUSION: Permanent urethral endoprostheses can produce excellent results in patients with recurrent urethral strictures.