Hepatocyte growth factor (HGF) receptor expression is inducible and is part of the delayed-early response to HGF.

The c-MET proto-oncogene encodes the tyrosine kinase receptor for hepatocyte growth factor (HGF), also known as scatter factor, a potent mitogen and motogen for epithelial cells. The level of the HGF receptor expressed by epithelial cells varies in different growth conditions, being lower in growth arrested confluent monolayers and higher in growing sparse cells. The amount of HGF receptor mRNA increases from 3- to 5-fold after stimulation of confluent monolayers by serum and up to 10-fold after stimulation of protein kinase C by 12-O-tetradecanoylphorbol-13-acetate (TPA). An increased level of the receptor mRNA was also observed after cell stimulation with nanomolar concentration of HGF itself. The effect was transient, dose, and time-dependent. Transcription of a reporter gene under control of the cloned 297 base pair c-MET promoter was also stimulated by serum, TPA, or HGF. The accumulation of specific mRNA is followed by appearance of the HGF receptor precursor protein, which is further processed to the receptor mature form. After HGF stimulation, HGF receptor expression follows c-FOS and c-JUN induction with a peak approximately 4 h. Pretreatment with the protein synthesis inhibitor puromycin strongly reduced the response to HGF, while cycloheximide alone increased the level of the receptor mRNA. These data show that c-MET behaves as a delayed early-response gene and suggest that the HGF response is autoamplified by inducing the specific receptor

RNF168, a new RING finger, MIU-containing protein that modifies chromatin by ubiquitination of histones H2A and H2AX

<p>Abstract</p> <p>Background</p> <p>Modulation of chromatin structure has emerged as a critical molecular device to control gene expression. Histones undergo different post-translational modifications that increase chromatin accessibility to a number of regulatory factors. Among them, histone ubiquitination appears relevant in nuclear processes that govern gene silencing, either by inhibiting or activating transcription, and maintain genome stability, acting as scaffold to properly organize the DNA damage response. Thus, it is of paramount importance the identification and the characterization of new ubiquitin ligases that address histones.</p> <p>Results</p> <p>We identified and characterized RNF168, a new chromatin-associated RING finger protein. We demonstrated that RNF168 is endowed with ubiquitin ligase activity both <it>in vitro </it>and <it>in vivo</it>, which targets histones H2A and H2AX, but not H2B, forming K63 polyubiquitin chains. We previously described the presence within RNF168 sequence of two MIU domains, responsible for the binding to ubiquitinated proteins. Here we showed that inactivation of the MIUs impairs ubiquitin binding ability <it>in vitro </it>and reduces chromatin association of RNF168 <it>in vivo</it>. Moreover, upon formation of DNA double strand breaks induced by chemical and physical agents, RNF168 is recruited to the DNA damage foci, where it co-localizes with γH2AX and 53BP1. The localization of RNF168 at the site of damage highly increases the local concentration of ubiquitinated proteins and determines the prolonged ubiquitination signal.</p> <p>Conclusion</p> <p>The RING finger protein RNF168 is a new ubiquitin ligase that functions as chromatin modifier, through histone ubiquitination. We hypothesize a dual function for RNF168. In normal condition RNF168 modifies chromatin structure by modulating ubiquitination of histone H2A. Upon DNA lesions, RNF168 is recruited to DNA damage response foci where it contributes to increase the amount of ubiquitinated proteins, thereby facilitating the downstream signalling cascade.</p

Composite Y internal thoracic artery–saphenous vein grafts: short-term angiographic results and vasoreactive profile

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Standard model anomalies: Lepton flavour non-universality and lepton g-2

We critically analyze the body of results that hints to the existence of New Physics from possible violations of lepton universality observed by the LHCb experiment in the $\mu/e$ ratios $R_{K}$ and $R_{K^*}$ to the $g-2$ lepton anomalies. The analysis begins with a theoretical, in depth, study of the $\mu/e$ ratios $R_{K}$ and $R_{K^*}$ as well as the process $B_s \rightarrow \mu^+ \mu^-$. Here we consider the impact of complex Wilson coefficients and derive constraints on their imaginary and real parts. We then move to a comprehensive comparison with experimental results. We show that, by fitting a single Wilson coefficient, the deviations from the Standard Model are at the $4.7\sigma$ level when including only the hadronic insensitive observables while it increases to $6.1\sigma$ when including also the hadronic sensitive ones. When switching on all relevant Wilson coefficients and combining both hadronic sensitive and insensitive data into the fit, the deviation from the Standard Model peaks at 7.2$\sigma$ and decreases at the $4.9\sigma$ level if we assume that the central values of $R_K$ and $R_K^{\ast}$ are taken to be unity. We further estimate the non-perturbative long distance hadronic contributions and show that their inclusion still requires New Physics to fit the data. We then introduce the $g-2$ lepton anomalies results. Different theoretical models are considered that can explain the discrepancies from the Standard Model. In the final part of our work we estimate the impact of the forthcoming data from LHCb (coming from LHC Run3) and Belle II, when it will have accumulated about $5~ab^{-1}$

FTY720 inhibits mesothelioma growth in vitro and in a syngeneic mouse model

Background: Malignant mesothelioma (MM) is a very aggressive type of cancer, with a dismal prognosis and inherent resistance to chemotherapeutics. Development and evaluation of new therapeutic approaches is highly needed. Immunosuppressant FTY720, approved for multiple sclerosis treatment, has recently raised attention for its anti-tumor activity in a variety of cancers. However, its therapeutic potential in MM has not been evaluated yet. Methods: Cell viability and anchorage-independent growth were evaluated in a panel of MM cell lines and human mesothelial cells (HM) upon FTY720 treatment to assess in vitro anti-tumor efficacy. The mechanism of action of FTY720 in MM was assessed by measuring the activity of phosphatase protein 2A (PP2A)-a major target of FTY720. The binding of the endogenous inhibitor SET to PP2A in presence of FTY720 was evaluated by immunoblotting and immunoprecipitation. Signaling and activation of programmed cell death were evaluated by immunoblotting and flow cytometry. A syngeneic mouse model was used to evaluate anti-tumor efficacy and toxicity profile of FTY720 in vivo. Results: We show that FTY720 significantly suppressed MM cell viability and anchorage-independent growth without affecting normal HM cells. FTY720 inhibited the phosphatase activity of PP2A by displacement of SET protein, which appeared overexpressed in MM, as compared to HM cells. FTY720 promoted AKT dephosphorylation and Bcl-2 degradation, leading to induction of programmed cell death, as demonstrated by caspase-3 and PARP activation, as well as by cytochrome c and AIF intracellular translocation. Moreover, FTY720 administration in vivo effectively reduced tumor burden in mice without apparent toxicity. Conclusions: Our preclinical data indicate that FTY720 is a potentially promising therapeutic agent for MM treatment

Sclerotherapy with polidocanol microfoam in head and neck venous and lymphatic malformations

Objective. Polidocanol sclerotherapy of head and neck venous malformations (VMs) and lymphatic malformations (LMs) has been reported only in limited series. In this manuscript we evaluated the efficacy and safety of polidocanol sclerotherapy in a series of head and neck venous and lymphatic malformations. Methods. This retrospective observational study analysed data on 20 head and neck VMs and LMs that underwent to percutaneous or endoscopic intra-lesional 3% polidocanol microfoam sclerotherapy at our institution. Clinical response was ranked as excellent, moderate and poor based on volume reduction by MRI and resolution of symptoms. Results. The median volume decreased from 19.3 mL to 5.8 mL after sclerotherapy (mean volume reduction: 72.98 ± 16.1%). An excellent-moderate response was observed in 94.4% of cases. We observed a mean volume reduction of 79.5 ± 16.1 in macrocystic LMs, of 76.1 ± 13.0% in VMs, of 60.5 ± 10.9% in mixed lymphatic ones and 42.5% in microcystic lymphatic ones. Conclusions. Polidocanol sclerotherapy appears to be an effective and safe treatment for venous and lymphatic head and neck malformations. We observed the best responses in macrocystic LMs and VMs, whereas mixed lymphatic ones showed a moderate response and microcystic lymphatic ones a poor response