BackgroundHypoxia plays a vital role in cancer epithelial to mesenchymal transition (EMT) and invasion. However, it is not quite clear how hypoxia may contribute to these events. Here we investigate the role of Hedgehog (Hh) signaling in hypoxia induced pancreatic cancer EMT and invasion.MethodsPancreatic cancer cells were cultured under controlled hypoxia conditions (3% O2) or normoxic conditions. HIF-1α siRNA, cyclopamine (a SMO antagonist) and GLI1 siRNA were used to inhibit HIF-1α transcription or Hh signaling activation. The effect of hypoxia and Hh signaling on cancer cell EMT and invasion were evaluated by Quantitative real-time PCR analysis, Western blot analysis and invasion assay.ResultsHere, we show that non-canonical Hh signaling is required as an important role to switch on hypoxia-induced EMT and invasion in pancreatic cancer cells. Moreover, our data demonstrate hypoxia induces EMT process as well as invasion, and activates the non-canonical Hh pathway without affecting sonic hedgehog homolog (SHH) expression. Moreover, these effects are reversible upon HIF-1α siRNA interference with unchanged SHH and patched1 (PTCH1) level. Furthermore, our data demonstrate that hypoxia induced invasion and EMT process are effectively inhibited by Smoothened (SMO) antagonist cyclopamine and GLI1 siRNA. In addition, GLI1 interference inhibited EMT progress with significantly suppressed vimentin expression, whereas inhibition of SMO through cyclopamine could not reduce vimentin level. This data indicate that hypoxia could trigger other factors (such as TGF-β, KRAS or RTK) bypassing SMO to activate GLI1 directly.ConclusionsOur findings suggest that Hh signaling modulates hypoxia induced pancreatic cancer EMT and invasion in a ligand-independent manner. Thus, Hh signaling may represent a promising therapeutic target for preventing pancreatic cancer progression.

Genetically engineered mouse (GEM) models are a pillar of functional cancer research. Here, we developed RapidCaP, a GEM modeling system that uses surgical injection for viral gene delivery to the prostate. We show that in Pten defi ciency, loss of p53 suffi ces to trigger metastasis to distant sites at greater than 50% penetrance by four months, consistent with results from human prostate cancer genome analysis. Live bioluminescence tracking showed that endogenous primary and metastatic disease responds to castration before developing lethal castration resistance. To our surprise, the resulting lesions showed no activation of Akt but activation of the Myc oncogene. Using RapidCaP, we fi nd that Myc drives local prostate metastasis and is critical for maintenance of metastasis, as shown by using the Brd4 inhibitor JQ1. Taken together, our data suggest that a "MYC-switch" away from AKT forms a critical and druggable event in PTEN -mutant prostate cancer metastasis and castration resistance. SIGNIFICANCE:The RapidCaP system introduces fast and fl exible genetics for functional analysis and therapy for endogenous metastatic prostate cancer. The approach introduces targeting of MYC as a critical strategy against PTEN -defi cient lethal prostate cancer. Cancer Discov; 4(3); 318-33. ©2014AACR.

The robotic surgical system has been applied in liver surgery. However, controversies concerns exist regarding a variety of factors including the safety, feasibility, efficacy, and cost-effectiveness of robotic surgery. To promote the development of robotic hepatectomy, this study aimed to evaluate the current status of robotic hepatectomy and provide sixty experts’ consensus and recommendations to promote its development. Based on the World Health Organization Handbook for Guideline Development, a Consensus Steering Group and a Consensus Development Group were established to determine the topics, prepare evidence-based documents, and generate recommendations. The GRADE Grid method and Delphi vote were used to formulate the recommendations. A total of 22 topics were prepared analyzed and widely discussed during the 4 meetings. Based on the published articles and expert panel opinion, 7 recommendations were generated by the GRADE method using an evidence-based method, which focused on the safety, feasibility, indication, techniques and cost-effectiveness of hepatectomy. Given that the current evidences were low to very low as evaluated by the GRADE method, further randomized-controlled trials are needed in the future to validate these recommendations.

SUMMARY A hallmark of advanced prostate cancer (PC) is the concomitant loss of PTEN and p53 function. To selectively eliminate such cells, we screened cytotoxic compounds on Pten−/−;Trp53−/− fibroblasts and their Pten-WT reference. Highly selective killing of Pten-null cells can be achieved by deguelin, a natural insecticide. Deguelin eliminates Pten-deficient cells through inhibition of mitochondrial complex I (CI). Five hundred-fold higher drug doses are needed to obtain the same killing of Pten-WT cells, even though deguelin blocks their electron transport chain equally well. Selectivity arises because mitochondria of Pten-null cells consume ATP through complex V, instead of producing it. The resulting glucose dependency can be exploited to selectively kill Pten-null cells with clinically relevant CI inhibitors, especially if they are lipophilic. In vivo, deguelin suppressed disease in our genetically engineered mouse model for metastatic PC. Our data thus introduce a vulnerability for highly selective targeting of incurable PC with inhibitors of CI.

Summary PTEN is proposed to function at the plasma membrane, where receptor tyrosine kinases are activated. However, the majority of PTEN is located throughout the cytoplasm. Here, we show that cytoplasmic PTEN is distributed along microtubules, tethered to vesicles via phosphatidylinositol 3-phosphate (PI(3)P), the signature lipid of endosomes. We demonstrate that the non-catalytic C2 domain of PTEN specifically binds PI(3)P through the CBR3 loop. Mutations render this loop incapable of PI(3)P binding and abrogate PTEN-mediated inhibition of PI 3-kinase/AKT signaling. This loss of function is rescued by fusion of the loop mutant PTEN to FYVE, the canonical PI(3)P binding domain, demonstrating the functional importance of targeting PTEN to endosomal membranes. Beyond revealing an upstream activation mechanism of PTEN, our data introduce the concept of PI 3-kinase signal activation on the vast plasma membrane that is contrasted by PTEN-mediated signal termination on the small, discrete surfaces of internalized vesicles.

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The mammalian genome comprises nuclear DNA (nDNA) derived from both parents and mitochondrial DNA (mtDNA) that is maternally inherited and encodes essential proteins required for oxidative phosphorylation. Thousands of copies of the circular mtDNA are present in most cell types that are packaged by TFAM into higher-order structures called nucleoids1. Mitochondria are also platforms for antiviral signalling2 and, due to their bacterial origin, mtDNA and other mitochondrial components trigger innate immune responses and inflammatory pathology 2,3 . We showed previously that instability and cytoplasmic release of mtDNA activates the cGAS-STING-Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use:

Disruption of the gut barrier results in severe clinical outcomes with no specific treatment. Metabolic disorders and destruction of enterocytes play key roles in gut barrier dysfunction. Irisin is a newly identified exercise hormone that regulates energy metabolism. However, the effect of irisin on gut barrier function remains unknown. The therapeutic effect of irisin on gut barrier dysfunction was evaluated in gut ischemia reperfusion (IR). The direct effect of irisin on gut barrier function was studied in Caco‐2 cells. Here, we discovered that serum and gut irisin levels were decreased during gut IR and that treatment with exogenous irisin restored gut barrier function after gut IR in mice. Meanwhile, irisin decreased oxidative stress, calcium influx and endoplasmic reticulum (ER) stress after gut IR. Moreover, irisin protected mitochondrial function and reduced enterocyte apoptosis. The neutralizing antibody against irisin significantly aggravated gut injury, oxidative stress and enterocyte apoptosis after gut IR. Further studies revealed that irisin activated the AMPK‐UCP 2 pathway via binding to the integrin αVβ5 receptor. Inhibition of integrin αVβ5, AMPK or UCP 2 abolished the protective role of irisin in gut barrier function. In conclusion, exogenous irisin restores gut barrier function after gut IR via the integrin αVβ5‐AMPK‐UCP 2 pathway.