Endogenous Alkylglycerol Functions As a Mediator of Protein Kinase C Activity and Cell Proliferation

To explore the possibility that 1-O-alkyl-sn-glycerol (alkylglycerol) may serve a regulatory role in the control of cell proliferation or PKC activity, we examined the ability of alkylglycerol to influence PKC activity and subcellular distribution as well as the ability of alkylglycerol to effect cell proliferation. MDCK cells grown to confluence show a loss of PKC activity associated with the membrane, as reported in fibroblasts. Preconfluent cultures of MDCK cells have a high level of PKC activity associated with the membrane. However, treatment of preconfluent cultures with alkylglycerol causes a reduction of PKC activity. A similar inhibition was observed with alkylglycerol when cells were treated with TPA, an activator of PKC. To confirm that alkylglycerol was exerting an effect directly on PKC, alkylglycerol was shown to inhibit PKC activity in vitro in a dose dependent manner. Since PKC exists as a family of closely related isozymes, we have determined the effects of growth arrest and alkylglycerol treatment on PKC $\rm\alpha,\ \epsilon,\ and\ \zeta$ (expressed in MDCK cells). The active forms of PKC $\alpha$ and $\epsilon$ are lost early in the growth of MDCK cells during the endogenous accumulation of alkylglycerol and synthetic alkylglycerol inhibits the membrane form of PKC $\alpha$ and $\epsilon.$ However, alkylglycerol inhibits the TPA induced translocation of PKC $\alpha$ but not $\epsilon$ suggesting a differential inhibition among these isoforms. Neither TPA or alkylglycerol had any effects on the distribution of PKC $\zeta.$ To examine the effect of alkylglycerol on cell proliferation, Swiss 3T3 cells were used. GLC analysis shows that 3T3 cells accumulate alkylglycerol in a similar manner as MDCK cells. Since this accumulation occurs just prior to cell growth arrest, the effects of alkylglycerol on preconfluent cells was observed. Preconfluent cultures of 3T3 cells were treated with alkylglycerol on day 1 of growth. After 8 days of culture, the treated group showed a slower growth rate and saturation density. Furthermore, after these cells were reseeded in the absence of alkylglycerol, the original growth rate and saturation density returned. Thus alkylglycerol induces a decrease in cell proliferation without causing any detrimental effects. Similarly, alkylglycerol was found to inhibit the induction of mitogenesis by TPA (a PKC dependent pathway) and these effects were shown not to be stereospecific. To further investigate the effect of alkylglycerol on cell proliferation, the content of the monoglycerides in ras-transformed cells was analyzed. These cells have lost contact dependent growth arrest indicating a disruption of cell growth regulation. We observed a massive increase in the content of alkylglycerol during the culture of ras transformed cells. This increase is 3 fold higher than MDCK or 3T3 cells. This raises the possibility that alkylglycerol may be the end result of an increased number of cell-cell contacts. We have observed an increase in the accumulation of alkylglycerol in normal and ras-transformed cells. This accumulation is accompanied by a decrease in PKC activity and alkylglycerol was shown to be a potent in vitro inhibitor of PKC. Similarly, alkylglycerol was shown to inhibit PKC $\alpha$ under stimulation by TPA. Alkylgylcerol is a inhibitor of the TPA induced induction of mitogenesis and slows the growth rate of proliferating cultures of 3T3 cells. These results indicate that the endogenous ether-linked glycerolipid, alkylglycerol, is a regulator of cell proliferation through its inhibitory effects on protein kinase C. (Abstract shortened by UMI.

Reversal of oncogene transformation and suppression of tumor growth by the novel IGF1R kinase inhibitor A-928605

BACKGROUND: The insulin-like growth factor (IGF) axis is an important signaling pathway in the growth and survival of many cell and tissue types. This pathway has also been implicated in many aspects of cancer progression from tumorigenesis to metastasis. The multiple roles of IGF signaling in cancer suggest that inhibition of the pathway might yield clinically effective therapeutics. METHODS: We describe A-928605, a novel pyrazolo [3,4-d]pyrimidine small molecule inhibitor of the receptor tyrosine kinases (IGF1R and IR) responsible for IGF signal transduction. This compound was first tested for its activity and selectivity via conventional in vitro kinome profiling and cellular IGF1R autophosphorylation. Additionally, cellular selectivity and efficacy of A-928605 were analyzed in an IGF1R oncogene-addicted cell line by proliferation, signaling and microarray studies. Finally, in vivo efficacy of A-928605 was assessed in the oncogene-addicted cell line and in a neuroblastoma model as a single agent as well as in combination with clinically approved therapeutics targeting EGFR in models of pancreatic and non-small cell lung cancers. RESULTS: A-928605 is a selective IGF1R inhibitor that is able to abrogate activation of the pathway both in vitro and in vivo. This novel compound dosed as a single agent is able to produce significant growth inhibition of neuroblastoma xenografts in vivo. A-928605 is also able to provide additive effects when used in combination with clinically approved agents directed against EGFR in non-small cell lung and human pancreatic tumor models. CONCLUSION: These results suggest that a selective IGF1R inhibitor such as A-928605 may provide a useful clinical therapeutic for IGF pathway affected tumors and warrants further investigation

Legitimacy in the Multilevel European Polity

In order to be simultaneously effective and liberal, governments must normally be able to count on voluntary compliance – which, in turn, depends on the support of socially shared legitimacy beliefs. In Western constitutional democracies, such beliefs are derived from the distinct but coexistent traditions of “republican” and “liberal” political philosophy. When judged by these criteria, the European Union – if considered by itself – appears as a thoroughly liberal polity which, however, lacks all republican credentials. But this view (which seems to structure the debates about the “European democratic deficit”) ignores the multilevel nature of the European polity, where the compliance of citizens is requested, and needs to be legitimated by member states – whereas the Union appears as a “government of governments” which is entirely dependent on the voluntary compliance of its member states. What matters primarily, therefore, is the compliance-legitimacy relationship between the Union and its member states – which, however, is normatively constrained by the basic compliance-legitimacy relationship between member governments and their constituents. Given the high consensus requirements of European legislation, member governments could and should be able to assume political responsibility for European policies in which they had a voice, and to justify them in “communicative discourses” in the national public space. This is not necessarily true of “non-political” policy choices imposed by the European Court of Justice. By enforcing its “liberal” program of liberalization and deregulation, the ECJ may presently be undermining the “republican” bases of member-state legitimacy. Where this is the case, open non-compliance is a present danger, and political controls of judicial legislation may be called for.Um gleichzeitig effektiv und liberal sein zu können, ist staatliche Herrschaft auf freiwillige Folgebereitschaft angewiesen – die ihrerseits der Unterstützung durch sozial geteilte Legitimitätsüberzeugungen bedarf. In den demokratischen Verfassungsstaaten des Westens werden solche Überzeugungen aus den unterschiedlichen, aber komplementär zusammenwirkenden Traditionen der „republikanischen“ und der „liberalen“ politischen Philosophie hergeleitet. An diesen Kriterien gemessen erscheint die Europäische Union – wenn man sie für sich betrachtet – als eine „liberale“ politische Ordnung, der jedoch alle „republikanischen“ Legitimitätsmerkmale fehlen. Aber eine solche Sichtweise, die auch die derzeitige Diskussion über ein „europäisches Demokratiedefizit“ bestimmt, verkennt den Mehrebenencharakter des europäischen Gemeinwesens. In ihm sind es die Mitgliedstaaten, die Entscheidungen der Union gegenüber den eigenen Bürgern durchsetzen und auch legitimieren müssen, während es für die Union ihrerseits auf die freiwillige Folgebereitschaft ihrer Mitgliedstaaten ankommt. Dabei werden diese jedoch durch die normativen Grundlagen ihrer eigenen Legitimität begrenzt. Politische Entscheidungen auf europäischer Ebene setzen breiten Konsens voraus, und die Regierungen sollten sie deshalb auch gegenüber den eigenen Bürgern in „kommunikativen Diskursen“ vertreten und dafür die politische Verantwortung übernehmen können. Dies gilt jedoch nicht notwendigerweise auch für Entscheidungen der europäischen Politik, die im nichtpolitischen Modus ohne Beteiligung des Rates und des Parlaments vom Europäischen Gerichtshof bestimmt werden. Mit der gegenwärtigen Radikalisierung seines „liberalen“ Programms der Liberalisierung und Deregulierung des nationalen Rechts könnte der Gerichtshof in der Tat die „republikanischen“ Grundlagen der mitgliedstaatlichen Legitimität unterminieren. In diesem Falle könnte die Union sich nicht länger auf die Folgebereitschaft ihrer Mitgliedstaaten verlassen. Um diese Gefahr für die europäische Integration zu vermeiden, sollte eine stärkere politische Kontrolle der richterlichen Rechtsetzung erwogen werden.1 Legitimacy Republican and liberal legitimating discourses Constitutional democracies – and the EU? 2 Legitimacy in multilevel polities 3 Legitimating member state compliance Political modes of policy making Non-political policy making 4 The need for justification 5 The Court is pushing against the limits of justifiability 6 The liberal undermining of republican legitimacy 7 Needed: A political balance of community and autonomy Reference

Colorectal and other cancer risks for carriers and noncarriers from families with a DNA mismatch repair gene mutation: A Prospective Cohort Study

To determine whether cancer risks for carriers and noncarriers from families with a mismatch repair (MMR) gene mutation are increased above the risks of the general population. We prospectively followed a cohort of 446 unaffected carriers of an MMR gene mutation (MLH1, n = 161; MSH2, n = 222; MSH6, n = 47; and PMS2, n = 16) and 1,029 their unaffected relatives who did not carry a mutation every 5 years at recruitment centers of the Colon Cancer Family Registry. For comparison of cancer risk with the general population, we estimated country-, age-, and sex-specific standardized incidence ratios (SIRs) of cancer for carriers and noncarriers. Over a median follow-up of 5 years, mutation carriers had an increased risk of colorectal cancer (CRC; SIR, 20.48; 95% CI, 11.71 to 33.27; P < .001), endometrial cancer (SIR, 30.62; 95% CI, 11.24 to 66.64; P < .001), ovarian cancer (SIR, 18.81; 95% CI, 3.88 to 54.95; P < .001), renal cancer (SIR, 11.22; 95% CI, 2.31 to 32.79; P < .001), pancreatic cancer (SIR, 10.68; 95% CI, 2.68 to 47.70; P = .001), gastric cancer (SIR, 9.78; 95% CI, 1.18 to 35.30; P = .009), urinary bladder cancer (SIR, 9.51; 95% CI, 1.15 to 34.37; P = .009), and female breast cancer (SIR, 3.95; 95% CI, 1.59 to 8.13; P = .001). We found no evidence of their noncarrier relatives having an increased risk of any cancer, including CRC (SIR, 1.02; 95% CI, 0.33 to 2.39; P = .97). We confirmed that carriers of an MMR gene mutation were at increased risk of a wide variety of cancers, including some cancers not previously recognized as being a result of MMR mutations, and found no evidence of an increased risk of cancer for their noncarrier relatives

Legitimacy intermediation in the multilevel European polity and its collapse in the euro crisis

This essay re-examines the dual – republican and liberal – foundations of democratic legitimacy in the Western traditions of normative political theory. Considered in isolation, the European Union conforms to liberal standards but cannot satisfy republican criteria. Given these conflicting standards, debates on the alleged European democratic deficit have remained inconclusive. Moreover, they have failed to pay sufficient attention to the multilevel character of the European polity and to the normative potential of legitimacy intermediation in its two-step compliance and legitimating relationships. I argue, however, that the capacity of democratic member states to legitimate the exercise of European governing functions is being destroyed in the present euro crisis, and I briefly discuss the implications of this new constellation.In der westlichen Tradition der normativen politischen Theorie beruht demokratische Legitimität auf der doppelten Grundlage republikanischer und liberaler Prinzipien. Für sich betrachtet entspricht die Europäische Union zwar liberalen Kriterien, aber eben nicht den republikanischen Anforderungen. Angesichts so unterschiedlicher Kriterien konnte es auch im Streit über das angebliche europäische Demokratiedefizit keine Einigung geben. Überdies ignorierte diese Diskussion den Mehrebenen-Charakter der europäischen Politik und das normative Potenzial der Legitimationsvermittlung zwischen Union und Bürgern durch die demokratisch verfassten Mitgliedstaaten. Die gegenwärtige Eurokrise allerdings zerstört die Fähigkeit demokratischer Mitgliedstaaten, die Ausübung europäischer Herrschaftsfunktionen zu legitimieren. Der Aufsatz erörtert die Implikationen dieser neuen Konstellation.1 Introduction 2 Legitimacy discourses The republican discourse The liberal discourse Differences 3 Constitutional democracies – and the European Union? 4 Legitimacy intermediation in the multilevel European polity 5 The end of legitimacy intermediation in the euro crisis Monetary Union and the failure of output legitimacy Rescuing the euro through supranational intervention 6 Legitimate supranational government? Input-oriented European legitimacy? 7 Reducing the burden on European legitimacy Reference

The Role of Economic Policy in Climate Change Adaptation

This paper assesses the role of the public sector in adaptation to climate change. We first offer a definition and categorisation of climate change adaptation. We then consider the primary economic principles that can guide the assignment of adaptation tasks to either the private or the public sector, as well as those guiding assignment within the public sector itself. We find that the role of the state in adaptation policy is limited. We identify information policy, the provision of a suitable regulatory framework in some markets, the formation of human capital and policies that foster economic growth and technological and medical knowledge as the main areas in which the public sector has a role in climate change adaptation