Molecular mechanisms underlying TNFα-induced mitochondrial fragmentation in human airway smooth muscle cells

Tumor necrosis factor α (TNFα), a proinflammatory cytokine, plays a significant role in mediating the effects of acute inflammation in response to allergens, pollutants, and respiratory infections. Previously, we showed that acute exposure to TNFα induces mitochondrial fragmentation in human airway smooth muscle (hASM) cells, which is associated with increased expression of dynamin-related protein 1 (DRP1). Phosphorylation of DRP1 at serine 616 (pDRP1S616) promotes its translocation and binding to the outer mitochondrial membrane (OMM) and mediates mitochondrial fragmentation. Previously, we reported that TNFα exposure triggers protein unfolding and triggers an endoplasmic reticulum (ER) stress response involving phosphorylation of inositol-requiring enzyme 1α (pIRE1α) at serine 724 (pIRE1αS724) and subsequent splicing of X-box binding protein 1 (XBP1s) in hASM cells. We hypothesize that TNFα-mediated activation of the pIRE1αS724/XBP1s ER stress pathway in hASM cells transcriptionally activates genes that encode kinases responsible for pDRP1S616 phosphorylation. Using 3-D confocal imaging of MitoTracker green-labeled mitochondria, we found that TNFα treatment for 6 h induces mitochondrial fragmentation in hASM cells. We also confirmed that 6 h TNFα treatment activates the pIRE1α/XBP1s ER stress pathway. Using in silico analysis and ChIP assay, we showed that CDK1 and CDK5, kinases involved in the phosphorylation of pDRP1S616, are transcriptionally targeted by XBP1s. TNFα treatment increased the binding affinity of XBP1s on the promoter regions of CDK1 and CDK5, and this was associated with an increase in pDRP1S616 and mitochondria fragmentation. This study reveals a new underlying molecular mechanism for TNFα-induced mitochondrial fragmentation in hASM cells.NEW & NOTEWORTHY Airway inflammation is increasing worldwide. Proinflammatory cytokines mediate an adaptive mechanism to overcome inflammation-induced cellular stress. Previously, we reported that TNFα mediates hASM cellular responses, leading to increased force and ATP consumption associated with increased O2 consumption, and oxidative stress. This study indicates that TNFα induces ER stress, which induces mitochondrial fragmentation via pIRE1αS724/XBP1s mediated CDK1/5 upregulation and pDRP1S616 phosphorylation. Mitochondrial fragmentation may promote hASM mitochondrial biogenesis to maintain healthy mitochondrial pool.

Influence of polymorphisms in TNF-α and IL1β on susceptibility to alcohol induced liver diseases and therapeutic potential of miR-124-3p impeding TNF-α/IL1β mediated multi-cellular signaling in liver microenvironment

Background and aims

Alcoholic liver disease (ALD) is the leading cause of the liver cirrhosis related death worldwide. Excessive alcohol consumption resulting enhanced gut permeability which trigger sensitization of inflammatory cells to bacterial endotoxins and induces secretion of cytokines, chemokines leading to activation of stellate cells, neutrophil infiltration and hepatocyte injury followed by steatohepatitis, fibrosis and cirrhosis. But all chronic alcoholics are not susceptible to ALD. This study investigated the causes of differential immune responses among ALD patients and alcoholic controls (ALC) to identify genetic risk factors and assessed the therapeutic potential of a microRNA, miR-124-3p.

Materials and methods

Bio-Plex Pro™ Human Chemokine analysis/qRT-PCR array was used for identification of deregulated immune genes. Sequencing/luciferase assay/ELISA detected and confirmed the polymorphisms. THP1 co-cultured with HepG2/LX2/HUVEC and apoptosis assay/qRT-PCR/neutrophil migration assay were employed as required.

Results

The combined data analysis of the GSE143318/Bio-Plex Pro™ Human Chemokine array and qRT-PCR array revealed that six genes (TNFα/IL1β/IL8/MCP1/IL6/TGFβ) were commonly overexpressed in both serum/liver tissue of ALD-patients compared to ALC. The promoter sequence analysis of these 6 genes among ALD (n=322)/ALC (n=168) samples revealed that only two SNPs, rs361525(G/A) at -238 in TNF-α/rs1143627(C/T) at -31 in IL1β were independently associated with ALD respectively. To evaluate the functional implication of these SNPs on ALD development, the serum level of TNF-α/IL1β was verified and observed significantly higher in ALD patients with risk genotypes TNF-α-238GA/IL1β-31CT+TT than TNF-α-238GG/IL1β-31CC. The TNF-α/IL1β promoter Luciferase-reporter assays showed significantly elevated level of luciferase activities with risk genotypes -238AA/-31TT than -238GG/-31CC respectively. Furthermore, treatment of conditioned medium of TNF-α/IL1β over-expressed THP1 cells to HepG2/LX2/HUVEC cells independently showed enhanced level of ER stress and apoptosis in HepG2/increased TGFβ and collagen-I production by LX2/huge neutrophil infiltration through endothelial layer. However, restoration of miR-124-3p in THP1 attenuated such inter-cellular communications and hepatocyte damage/collagen production/neutrophil infiltration were prohibited. Target analysis/luciferase-reporter assays revealed that both TNF-α/IL1β were inhibited by miR-124-3p along with multiple genes from TLR4 signaling/apoptosis/fibrogenesis pathways including MYD88, TRAF3/TRADD, Caspase8/PDGFRA, TGFβR2/MCP1, and ICAM1 respectively.

Conclusion

Thus, rs361525(G/A) in TNF-α and rs1143627(C/T) in IL1β gene may be used as early predictors of ALD susceptibility among East Indian population. Impeding overexpressed TNF-α/IL1β and various genes from associated immune response pathways, miR-124-3p exhibits robust therapeutic potential for ALD patients.

Chemical Chaperone 4-PBA Mitigates Tumor Necrosis Factor Alpha-Induced Endoplasmic Reticulum Stress in Human Airway Smooth Muscle

Airway inflammation and pro-inflammatory cytokines such as tumor necrosis factor alpha (TNFα) underlie the pathophysiology of respiratory diseases, including asthma. Previously, we showed that TNFα activates the inositol-requiring enzyme 1α (IRE1α)/X-box binding protein 1 spliced (XBP1s) endoplasmic reticulum (ER) stress pathway in human airway smooth muscle (hASM) cells. The ER stress pathway is activated by the accumulation of unfolded proteins in the ER. Accordingly, chemical chaperones such as 4-phenylbutyric acid (4-PBA) may reduce ER stress activation. In the present study, we hypothesized that chemical chaperone 4-PBA mitigates TNFα-induced ER stress in hASM cells. hASM cells were isolated from bronchiolar tissue obtained from five patients with no history of smoking or respiratory diseases. The hASM cells' phenotype was confirmed via the expression of alpha-smooth muscle actin and elongated morphology. hASM cells from the same patient sample were then separated into three 12 h treatment groups: (1) TNFα (20 ng/mL), (2) TNFα + 4-PBA (1 μM, 30 min pretreatment), and (3) untreated control. The expressions of total IRE1α and phosphorylated IRE1α (pIRE1αS724) were determined through Western blotting. The splicing of XBP1 mRNA was analyzed using RT-PCR. We found that TNFα induced an increase in pIRE1αS724 phosphorylation, which was mitigated by treatment with chemical chaperone 4-PBA. We also found that TNFα induced an increase in XBP1s mRNA, which was also mitigated by treatment with chemical chaperone 4-PBA. These results support our hypothesis and indicate that chemical chaperone 4-PBA treatment mitigates TNFα-induced ER stress in hASM cells.

Chemogenetic inhibition of TrkB signalling reduces phrenic motor neuron survival and size

Brain derived neurotrophic factor (BDNF) signalling through its high-affinity tropomyosin receptor kinase B (TrkB) is known to have potent effects on motor neuron survival and morphology during development and in neurodegenerative diseases. Here, we employed a novel 1NMPP1 sensitive TrkB^F616 rat model to evaluate the effect of 14 days inhibition of TrkB signalling on phrenic motor neurons (PhMNs). Adult female and male TrkB^F616 rats were divided into 1NMPP1 or vehicle treated groups. Three days prior to treatment, PhMNs in both groups were initially labeled via intrapleural injection of Alexa-Fluor-647 cholera toxin B (CTB). After 11 days of treatment, retrograde axonal uptake/transport was assessed by secondary labeling of PhMNs by intrapleural injection of Alexa-Fluor-488 CTB. After 14 days of treatment, the spinal cord was excised 100 μm thick spinal sections containing PhMNs were imaged using two-channel confocal microscopy. TrkB inhibition reduced the total number of PhMNs by ~16 %, reduced the mean PhMN somal surface areas by ~25 %, impaired CTB uptake 2.5-fold and reduced the estimated PhMN dendritic surface area by ~38 %. We conclude that inhibition of TrkB signalling alone in adult TrkB^F616 rats is sufficient to lead to PhMN loss, morphological degeneration and deficits in retrograde axonal uptake/transport.

Molecular Mechanisms Underlying TNFα-Induced Mitochondrial Biogenesis in Human Airway Smooth Muscle

Proinflammatory cytokines such as TNFα mediate airway inflammation. Previously, we showed that TNFα increases mitochondrial biogenesis in human ASM (hASM) cells, which is associated with increased PGC1α expression. We hypothesized that TNFα induces CREB and ATF1 phosphorylation (pCREBS133 and pATF1S63), which transcriptionally co-activate PGC1α expression. Primary hASM cells were dissociated from bronchiolar tissue obtained from patients undergoing lung resection, cultured (one-three passages), and then differentiated by serum deprivation (48 h). hASM cells from the same patient were divided into two groups: TNFα (20 ng/mL) treated for 6 h and untreated controls. Mitochondria were labeled using MitoTracker green and imaged using 3D confocal microscopy to determine mitochondrial volume density. Mitochondrial biogenesis was assessed based on relative mitochondrial DNA (mtDNA) copy number determined by quantitative real-time PCR (qPCR). Gene and/or protein expression of pCREBS133, pATF1S63, PCG1α, and downstream signaling molecules (NRFs, TFAM) that regulate transcription and replication of the mitochondrial genome, were determined by qPCR and/or Western blot. TNFα increased mitochondrial volume density and mitochondrial biogenesis in hASM cells, which was associated with an increase in pCREBS133, pATF1S63 and PCG1α expression, with downstream transcriptional activation of NRF1, NRF2, and TFAM. We conclude that TNFα increases mitochondrial volume density in hASM cells via a pCREBS133/pATF1S63/PCG1α-mediated pathway.

Modulating sphingosine 1-phosphate receptor signaling skews intrahepatic leukocytes and attenuates murine nonalcoholic steatohepatitis

Sphingosine 1-phosphate (S1P) is a bioactive sphingolipid associated with nonalcoholic steatohepatitis (NASH). Immune cell-driven inflammation is a key determinant of NASH progression. Macrophages, monocytes, NK cells, T cells, NKT cells, and B cells variably express S1P receptors from a repertoire of 5 receptors termed S1P₁ - S1P₅. We have previously demonstrated that non-specific S1P receptor antagonism ameliorates NASH and attenuates hepatic macrophage accumulation. However, the effect of S1P receptor antagonism on additional immune cell populations in NASH remains unknown. We hypothesized that S1P receptor specific modulation may ameliorate NASH by altering leukocyte recruitment. A murine NASH model was established by dietary feeding of C57BL/6 male mice with a diet high in fructose, saturated fat, and cholesterol (FFC) for 24 weeks. In the last 4 weeks of dietary feeding, the mice received the S1P_1,4,5 modulator Etrasimod or the S1P₁ modulator Amiselimod, daily by oral gavage. Liver injury and inflammation were determined by histological and gene expression analyses. Intrahepatic leukocyte populations were analyzed by flow cytometry, immunohistochemistry, and mRNA expression. Alanine aminotransferase, a sensitive circulating marker for liver injury, was reduced in response to Etrasimod and Amiselimod treatment. Liver histology showed a reduction in inflammatory foci in Etrasimod-treated mice. Etrasimod treatment substantially altered the intrahepatic leukocyte populations through a reduction in the frequency of T cells, B cells, and NKT cells and a proportional increase in CD11b⁺ myeloid cells, polymorphonuclear cells, and double negative T cells in FFC-fed and control standard chow diet (CD)-fed mice. In contrast, FFC-fed Amiselimod-treated mice showed no changes in the frequencies of intrahepatic leukocytes. Consistent with the improvement in liver injury and inflammation, hepatic macrophage accumulation and the gene expression of proinflammatory markers such as Lgals3 and Mcp-1 were decreased in Etrasimod-treated FFC-fed mice. Etrasimod treated mouse livers demonstrated an increase in non-inflammatory (Marco) and lipid associated (Trem2) macrophage markers. Thus, S1P_1,4,5 modulation by Etrasimod is more effective than S1P₁ antagonism by Amiselimod, at the dose tested, in ameliorating NASH, likely due to the alteration of leukocyte trafficking and recruitment. Etrasimod treatment results in a substantial attenuation of liver injury and inflammation in murine NASH.

Mitochondrial adaptations to inactivity in diaphragm muscle fibers

Type I and IIa diaphragm muscle (DIAm) fibers comprise slow and fast fatigue-resistant motor units that are recruited to accomplish breathing and thus have a high duty cycle. In contrast, type IIx/IIb fibers comprise more fatigable fast motor units that are infrequently recruited for airway protective and straining behaviors. We hypothesize that mitochondrial structure and function in type I and IIa DIAm fibers adapt in response to inactivity imposed by spinal cord hemisection at C₂ (C₂SH). At 14 days after C₂SH, the effect of inactivity on mitochondrial structure and function was assessed in DIAm fibers. Mitochondria in DIAm fibers were labeled using MitoTracker Green (Thermo Fisher Scientific), imaged in three-dimensions (3-D) by fluorescence confocal microscopy, and images were analyzed for mitochondrial volume density (MVD) and complexity. DIAm homogenate from either side was assessed for PGC1α, Parkin, MFN2, and DRP1 using Western blot. In alternate serial sections of the same DIAm fibers, the maximum velocity of the succinate dehydrogenase reaction (SDH_max) was determined using a quantitative histochemical technique. In all groups and both sides of the DIAm, type I and IIa DIAm fibers exhibited higher MVD, with more filamentous mitochondria and had higher SDH_max normalized to both fiber volume and mitochondrial volume compared with type IIx/IIb Diam fibers. In the inactive right side of the DIAm, mitochondria became fragmented and MVD decreased in all fiber types compared with the intact side and sham controls, consistent with the observed reduction in PGC1α and increased Parkin and DRP1 expression. In the inactive side of the DIAm, the reduction in SDH_max was found only for type I and IIa fibers. These results show that there are intrinsic fiber-type-dependent differences in the structure and function of mitochondria in DIAm fibers. Following C₂SH-induced inactivity, mitochondrial structure (MVD and fragmentation) and function (SDH_max) were altered, indicating that inactivity influences all DIAm fiber types, but inactivity disproportionately affected SDH_max in the more intrinsically active type I and IIa fibers.NEW & NOTEWORTHY Two weeks of diaphragm (DIAm) inactivity imposed by C2SH caused reduced mitochondrial volume density, mitochondrial fragmentation, and a concomitant reduction of SDH_max in type I and IIa DIAm fibers on the lesioned side. Type I and IIa DIAm fibers were far more sensitive to inactivation than type IIx/IIb fibers, which exhibited little pathology. Our results indicate that mitochondria in DIAm fibers are plastic in response to varying levels of activity.

A Comparative Proteomic Analysis of Extracellular Vesicles Associated With Lipotoxicity

Extracellular vesicles (EVs) are emerging mediators of intercellular communication in nonalcoholic steatohepatitis (NASH). Palmitate, a lipotoxic saturated fatty acid, activates hepatocellular endoplasmic reticulum stress, which has been demonstrated to be important in NASH pathogenesis, including in the release of EVs. We have previously demonstrated that the release of palmitate-stimulated EVs is dependent on the de novo synthesis of ceramide, which is trafficked by the ceramide transport protein, STARD11. The trafficking of ceramide is a critical step in the release of lipotoxic EVs, as cells deficient in STARD11 do not release palmitate-stimulated EVs. Here, we examined the hypothesis that protein cargoes are trafficked to lipotoxic EVs in a ceramide-dependent manner. We performed quantitative proteomic analysis of palmitate-stimulated EVs in control and STARD11 knockout hepatocyte cell lines. Proteomics was performed on EVs isolated by size exclusion chromatography, ultracentrifugation, and density gradient separation, and EV proteins were measured by mass spectrometry. We also performed human EV proteomics from a control and a NASH plasma sample, for comparative analyses with hepatocyte-derived lipotoxic EVs. Size exclusion chromatography yielded most unique EV proteins. Ceramide-dependent lipotoxic EVs contain damage-associated molecular patterns and adhesion molecules. Haptoglobin, vascular non-inflammatory molecule-1, and insulin-like growth factor-binding protein complex acid labile subunit were commonly detected in NASH and hepatocyte-derived ceramide-dependent EVs. Lipotoxic EV proteomics provides novel candidate proteins to investigate in NASH pathogenesis and as diagnostic biomarkers for hepatocyte-derived EVs in NASH patients.

Circulating Extracellular Vesicles Carrying Sphingolipid Cargo for the Diagnosis and Dynamic Risk Profiling of Alcoholic Hepatitis

BACKGROUND AND AIMS

Alcoholic hepatitis (AH) is diagnosed by clinical criteria, although several objective scores facilitate risk stratification. Extracellular vesicles (EVs) have emerged as biomarkers for many diseases and are also implicated in the pathogenesis of AH. Therefore, we investigated whether plasma EV concentration and sphingolipid cargo could serve as diagnostic biomarkers for AH and inform prognosis to permit dynamic risk profiling of AH subjects.

APPROACH AND RESULTS

EVs were isolated and quantified from plasma samples from healthy controls, heavy drinkers, and subjects with end-stage liver disease (ESLD) attributed to cholestatic liver diseases and nonalcoholic steatohepatitis, decompensated alcohol-associated cirrhosis (AC), and AH. Sphingolipids were quantified by tandem mass spectroscopy. The median plasma EV concentration was significantly higher in AH subjects (5.38 × 10¹¹ /mL) compared to healthy controls (4.38 × 10¹⁰ /mL; P < 0.0001), heavy drinkers (1.28 × 10¹¹ /mL; P < 0.0001), ESLD (5.35 × 10¹⁰ /mL; P < 0.0001), and decompensated AC (9.2 × 10¹⁰ /mL; P < 0.0001) disease controls. Among AH subjects, EV concentration correlated with Model for End-Stage Liver Disease score. When EV counts were dichotomized at the median, survival probability for AH subjects at 90 days was 63.0% in the high-EV group and 90.0% in the low-EV group (log-rank P value = 0.015). Interestingly, EV sphingolipid cargo was significantly enriched in AH when compared to healthy controls, heavy drinkers, ESLD, and decompensated AC (P = 0.0001). Multiple sphingolipids demonstrated good diagnostic and prognostic performance as biomarkers for AH.

CONCLUSIONS

Circulating EV concentration and sphingolipid cargo signature can be used in the diagnosis and differentiation of AH from heavy drinkers, decompensated AC, and other etiologies of ESLD and predict 90-day survival permitting dynamic risk profiling.

IRE1A Stimulates Hepatocyte-Derived Extracellular Vesicles That Promote Inflammation in Mice With Steatohepatitis

BACKGROUND & AIMS

Endoplasmic reticulum to nucleus signaling 1 (ERN1, also called IRE1A) is a sensor of the unfolded protein response that is activated in the livers of patients with nonalcoholic steatohepatitis (NASH). Hepatocytes release ceramide-enriched inflammatory extracellular vesicles (EVs) after activation of IRE1A. We studied the effects of inhibiting IRE1A on release of inflammatory EVs in mice with diet-induced steatohepatitis.

METHODS

C57BL/6J mice and mice with hepatocyte-specific disruption of Ire1a (IRE1α^Δhep) were fed a diet high in fat, fructose, and cholesterol to induce development of steatohepatitis or a standard chow diet (controls). Some mice were given intraperitoneal injections of the IRE1A inhibitor 4μ8C. Mouse liver and primary hepatocytes were transduced with adenovirus or adeno-associated virus that expressed IRE1A. Livers were collected from mice and analyzed by quantitative polymerase chain reaction and chromatin immunoprecipitation assays; plasma samples were analyzed by enzyme-linked immunosorbent assay. EVs were derived from hepatocytes and injected intravenously into mice. Plasma EVs were characterized by nanoparticle-tracking analysis, electron microscopy, immunoblots, and nanoscale flow cytometry; we used a membrane-tagged reporter mouse to detect hepatocyte-derived EVs. Plasma and liver tissues from patients with NASH and without NASH (controls) were analyzed for EV concentration and by RNAscope and gene expression analyses.

RESULTS

Disruption of Ire1a in hepatocytes or inhibition of IRE1A reduced the release of EVs and liver injury, inflammation, and accumulation of macrophages in mice on the diet high in fat, fructose, and cholesterol. Activation of IRE1A, in the livers of mice, stimulated release of hepatocyte-derived EVs, and also from cultured primary hepatocytes. Mice given intravenous injections of IRE1A-stimulated, hepatocyte-derived EVs accumulated monocyte-derived macrophages in the liver. IRE1A-stimulated EVs were enriched in ceramides. Chromatin immunoprecipitation showed that IRE1A activated X-box binding protein 1 (XBP1) to increase transcription of serine palmitoyltransferase genes, which encode the rate-limiting enzyme for ceramide biosynthesis. Administration of a pharmacologic inhibitor of serine palmitoyltransferase to mice reduced the release of EVs. Levels of XBP1 and serine palmitoyltransferase were increased in liver tissues, and numbers of EVs were increased in plasma, from patients with NASH compared with control samples and correlated with the histologic features of inflammation.

CONCLUSIONS

In mouse hepatocytes, activated IRE1A promotes transcription of serine palmitoyltransferase genes via XBP1, resulting in ceramide biosynthesis and release of EVs. The EVs recruit monocyte-derived macrophages to the liver, resulting in inflammation and injury in mice with diet-induced steatohepatitis. Levels of XBP1, serine palmitoyltransferase, and EVs are all increased in liver tissues from patients with NASH. Strategies to block this pathway might be developed to reduce liver inflammation in patients with NASH.

A splenic 'cyst': histology confirmed splenic sarcoma

Primary malignant fibrous histiocytoma, now classified as pleomorphic undifferentiated sarcoma, is the most common soft-tissue sarcoma in adult life. Primary splenic pleomorphic undifferentiated sarcoma is extremely rare and aggressive, and is associated with a poor prognosis; only 14 cases of splenic pleomorphic undifferentiated sarcoma have been documented in the English literature. We discuss a case of a 56-year-old woman with iron-deficiency anaemia, early satiety and left upper-quadrant pain, who was preoperatively diagnosed with a large splenic cyst following thorough investigation. This was excised in an elective procedure. Unfortunately, histology confirmed splenic pleomorphic undifferentiated sarcoma. Following a review and summary of the literature, we discuss key differentials between splenic cysts and splenic pleomorphic undifferentiated sarcoma. This case highlights that iron-deficiency anaemia is unusual in splenic cysts and more sinister causes must be considered.

Oncogenic potential of hepatitis B virus subgenotype D1 surpasses D3: significance in the development of hepatocellular carcinoma

Despite widespread distribution of hepatitis B virus (HBV)-genotype D, the clinical implications of its ten subgenotypes (D1-D10) have not been well documented. Here, we have investigated the impact of two major circulating HBV/D subgenotypes, D1 and D3 in Eastern India towards pathogenesis of liver disease progression to hepatocellular carcinoma (HCC). HBV subgenotypes were determined using full-length genome sequences of HBV isolates from patients with chronic hepatitis B (CHB), liver cirrhosis (LC) and HCC. Impact of D1 and D3 on viral lifecycle and disease progression was assessed by several in vitro assays. Phylogenetic tree analysis revealed that HBV/D1 and HBV/D3 were the two predominating HBV subgenotypes circulating in Eastern India. Interestingly, the frequency of patients infected with HBV/D1 was noticed progressively rising from CHB to HCC through LC while the increasing frequency of HBV/D3 declined suddenly in HCC implicating HBV/D1 might have greater oncogenic potential than HBV/D3. Similar to higher viral load noted in HCC patients infected with HBV/D1 than HBV/D3, the larger amount of intracellular/extracellular viral DNA and secreted HBsAg levels in transfected cell lines also implicated that HBV/D1 might replicate faster than HBV/D3. Again, higher expression of marker genes related to endoplasmic reticulum stress, epithelial-mesenchymal transition, DNA double strand breaks, angiogenesis etc. and faster rate of cellular migration and anchorage independent growth cumulatively suggested that compared to HBV/D3, HBV/D1 generates more liver injuries which eventually culminates into HCC. Therefore, our results highlight the importance of determination of subgenotypes of HBV in CHB patients, so that high-risk individual can be monitor periodically that may help to detect HCC at early stages.

StAR-related lipid transfer domain 11 (STARD11)-mediated ceramide transport mediates extracellular vesicle biogenesis

Extracellular vesicles are important carriers of cellular materials and have critical roles in cell-to-cell communication in both health and disease. Ceramides are implicated in extracellular vesicle biogenesis, yet the cellular machinery that mediates the formation of ceramide-enriched extracellular vesicles remains unknown. We demonstrate here that the ceramide transport protein StAR-related lipid transfer domain 11 (STARD11) mediates the release of palmitate-stimulated extracellular vesicles having features consistent with exosomes. Using palmitate as a model of lipotoxic diseases and as a substrate for ceramide biosynthesis in human and murine liver cell lines and primary mouse hepatocytes, we found that STARD11-deficient cells release fewer extracellular vesicles. Moreover, STARD11 reciprocally regulated exosome ceramide enrichment and cellular ceramide depletion. We further observed that in STARD11 knockout cells intracellular ceramide accumulates and that this apparent inability to transfer cellular ceramide into extracellular vesicles reduces cellular viability. Using endogenous markers, we uncovered structural and functional colocalization of the endoplasmic reticulum (ER), STARD11, and multivesicular bodies. This colocalization increased following palmitate treatment, suggesting a functional association that may mediate ceramide trafficking from the ER to the multivesicular body. However, the size and number of multivesicular bodies were comparable in WT and STARD11-knockout cells. In conclusion, we propose a model of how STARD11 mediates ceramide trafficking in palmitate-treated cells and stimulates exosome biogenesis.

Deletion of endoplasmic reticulum stress-responsive co-chaperone p58IPK protects mice from diet-induced steatohepatitis

AIM

Activation of PKR-like endoplasmic reticulum kinase (PERK), an endoplasmic reticulum stress sensor, is a feature of non-alcoholic steatohepatitis (NASH), yet regulators of PERK signaling remain undefined in this context. The protein p58^IPK regulates PERK; however, its role in NASH has not been examined. The aim of this study was to assess the in vivo role of p58^IPK in the pathogenesis of dietary NASH.

METHODS

Parameters of hepatocyte cell death, liver injury, inflammation, fibrosis, indirect calorimetry and PERK activation were assessed in p58^IPK knockout (p58^ipk-/- ) mice and their wild-type littermate controls. All animals were fed a diet enriched in fat, fructose, and cholesterol (FFC) for 20 weeks.

RESULTS

Activation of PERK was attenuated in FFC-fed p58^ipk-/- mice. Accordingly, FFC-fed p58^ipk-/- mice showed a reduction in hepatocyte apoptosis and death receptor expression, with a significant reduction in serum alanine transaminase values. Correspondingly, macrophage accumulation and fibrosis were significantly lower in FFC-fed p58^ipk-/- mice.

CONCLUSION

We have shown that, in an in vivo dietary NASH model, p58^IPK mediates hepatocyte apoptosis and liver injury, likely through PERK phosphorylation. In the absence of p58^IPK , PERK phosphorylation and NASH are attenuated. Inhibition of hepatic p58^IPK could be a future target for NASH therapy.

MiRNA199a-3p suppresses tumor growth, migration, invasion and angiogenesis in hepatocellular carcinoma by targeting VEGFA, VEGFR1, VEGFR2, HGF and MMP2

Increasing significance of tumor-stromal interaction in development and progression of cancer implies that signaling molecules in the tumor microenvironment (TME) might be the effective therapeutic targets for hepatocellular carcinoma (HCC). Here, the role of microRNA miR-199a-3p in the regulation of TME and development of HCC has been investigated by several in vitro and in vivo assays. Expression of miR-199a-3p was observed significantly low in HCC tissues and its overexpression remarkably inhibited in vivo tumor growth and metastasis to lung in NOD-SCID mice. In vitro restoration of miR-199a-3p expression either in endothelial cells (ECs) or in cancer cells (CACs) significantly diminished migration of ECs in co-culture assay. Again incubation of miR-199a-3p transfected ECs with either conditioned media (CM) of CACs or recombinant VEGF has reduced tube formation, in ECs and it was also dropped upon growth in CM of either anti-VEGF antibody-treated or miR-199a-3p-transfected CACs. In addition, bioinformatics and luciferase-reporter assays revealed that miR-199a-3p inhibited VEGF secretion from CACs and VEGFR1 and VEGFR2 expression on ECs and thus restricted cross talk between CACs and ECs. Again, restoration of miR-199a-3p in hepatic stellate cells (HSCs) reduced migration and invasion of CACs in co-culture assay, while it was enhanced by the overexpression of HGF suggesting miR-199a-3p has hindered HSC-CACs cross talk probably by inhibiting HGF and regulating matrix metalloproteinase MMP2, which were found as targets of miR-199a-3p subsequently by luciferase-reporter assay and gelatin zymography, respectively. Thus, these findings collectively highlight that miR-199a-3p restricts metastasis, invasion and angiogenesis in HCC and hence it may be considered as one of the powerful effective therapeutics for management of HCC patients.

Genetic Association and Gene-Gene Interaction Reveal Genetic Variations in ADH1B, GSTM1 and MnSOD Independently Confer Risk to Alcoholic Liver Diseases in India

Genetic susceptibility is an important modifier of clinical outcome and natural history of progression in Alcoholic liver disease (ALD). While the significance of ethnicity in this evolution is very clear, subtle inter-individual genetic variant(s) might be important and thus we investigated those in an Indian population. Fourteen markers were genotyped within two alcohol metabolism genes [Alcohol dehydrogenase (ADH) gene clusters (ADH1B and ADH1C) and Aldehyde dehydrogenase (ALDH2)], one microsomal ethanol oxidizing enzyme cytochrome p450 (CYP2E1) and three oxidative stress response (OSR) genes (MnSOD, GSTT1 and GSTM1) among 490 Bengali individuals (322 ALD and 168 control) from Eastern and North-Eastern India and validation was performed in a new cohort of 150 Bengali patients including 100 ALD and 50 advanced non-alcoholic steatohepatitis (NASH). Out of 14 genetic variants, carriage of 5 genotypes (rs2066701CC in ADH1B, rs1693425TT in ADH1C, rs4880TT in MnSOD and GSTT1/GSTM1 null, p-value <0.05) were noted significantly higher among ALD patients while inter or intra group gene-gene interaction analysis revealed that addition of risk genotype of any OSR gene enhanced the possibility of ALD synergistically. Multiple logistic regression analysis showed independent association of rs2066701CC, rs4880TT and GSTM1 null genotype with ALD while lower frequencies of those genotypes in advanced NASH patients further confirmed their causal relation to ALD. Thus these findings suggest that the three variants of ADH1C, MnSOD and GSTM1 can be used to identify individuals who are at high risk to develop ALD and may be helpful in proper management of Indian alcoholics.

Hepatic miR-126 is a potential plasma biomarker for detection of hepatitis B virus infected hepatocellular carcinoma

Controversies about the origin of circulating miRNAs have encouraged us to identify organ specific circulating miRNAs as disease biomarkers. To identify liver-specific miRNAs for hepatocellular carcinoma (HCC), global expression profiling of miRNAs in liver tissue of HBV-HCC and HBV-control with no or mild fibrosis was evaluated. A total of 40 differentially expressed miRNAs were identified in HCC. Among ten highly altered miRNAs, six miRNAs were successfully validated in tissues, whereas only two miRNAs, miR-126 and miR-142-3p showed increased expression in plasma of HBV-HCC compared to HBV-non-HCC patients. Subsequently, ROC curve analysis revealed that neither miR-126 nor miR-142-3p performed better than AFP in discriminating HCC from non-HCC while combination of each with AFP showed significantly higher efficiency rather than AFP alone (AUC: 0.922, 0.908 vs. 0.88; sensitivity: 0.84, 0.86 vs. 0.82 and specificity: 0.92, 0.94 vs. 0.86 respectively). Interestingly, triple combination of markers (miR-126 + miR-142-3p + AFP) showed no additive effect on efficiency (AUC: 0.925) over the dual combination. Again, the expression of only miR-126 was noticed significantly higher in HBV-HCC patients with low-AFP [<250 ng/ml] compared to either non-HCC or liver cirrhosis (AUC: 0.77, 0.64, respectively). Furthermore, no alteration in expression of mir-126 in HCV-HCC or non-viral-HCC revealed that miR-126 + AFP might be specific to HBV-HCC. To understand the physiological role of these two miRNAs in hepato-carcinogenesis, target genes related to cancer pathways (APAF1, APC2, CDKN2A, IRS1, CRKL, LIFR, EGR2) were verified. Thus, combination of circulating miR-126 + AFP is a promising noninvasive diagnostic biomarker for HBV-HCC and may be useful in the management of HCC patients.

Hepatitis B Virus X Protein Upregulates hELG1/ ATAD5 Expression through E2F1 in Hepatocellular Carcinoma

The precise mechanism by which HBx protein of hepatitis B virus (HBV) impacts on hepato-carcinogenesis remain largely elusive despite strong evidences for its' involvement in the process. Here, we have investigated the role of HBx on expression of a novel gene hELG1/ATAD5, which is required for genome maintenance and its' importance in hepatocarcinogenesis. This study has for the first time showed that the expression of this gene was significantly higher in human cancer such as HBV-associated hepatocellular carcinoma (HCC) and in different HCC cell lines compared to normal liver. In addition, a significant elevation in ATAD5 expression was also found in HBx transfected HCC cell lines implicating HBx mediated transcriptional regulation on ATAD5. Using different deletion mutant constructs of putative promoter, the active promoter region was first identified here and subsequently the regulatory region of HBx was mapped by promoter-luciferase assay. But ChIP assay with anti-HBx antibody revealed that HBx was not physically present in ATAD5 transcription machinery whereas anti-E2F1 antibody showed the presence of E2F1 in the complex. Luciferase assay with E2F1 binding site mutant had further confirmed it. Moreover, both loss-and gain-of-function studies of ATAD5 showed that ATAD5 could enhance HBV production in transfected cells whereas knock down of ATAD5 increased the sensitivity of HCC cell line to chemotherapeutics 5-fluorouracil. Overall, this data suggests that a positive feedback loop regulation between ATAD5 and HBV contributed to both viral replication and chemo-resistance of HCC cells.

Abstract 3969: Hepatic microRNA as biomarker for detection of hepatocellular carcinoma in high-risk chronic Hepatitis B patients

a) Absence of pathognomonic symptoms in patients with early phase of hepatocellular carcinoma (HCC) often leads to untreatable disease when diagnosed. Alpha-fetoprotein (AFP) with radiological images is the only potential HCC diagnosis option while disease prognosis remains dismal mandating necessity of biomarker identification with diagnostic, prognostic potentials as well as ability to assist in therapy. Thus this study aimed to identify non-invasive biomarker correlated with HCC pathogenesis by analyzing deregulated miRNAs in premalignant liver cirrhosis (LC) and in HCC.

b) Among 148 study subjects, 117 were chronic Hepatitis B virus (HBV) (NAsymptomatic- control = 28, NLC = 30, NHCC = 59), 14 chronic Hepatitis C virus (HCV) infected (NLC = 7, NHCC = 7) and 17 were uninfected control. Differential expression profiling of miRNAs in each of 4 HBV infected LC and HCC tissues were performed by comparing with 8 asymptomatic controls using microarray and validated by qRT-PCR. R packages were used to determine area under receiver operating characteristics (AUROC) curve and other statistical analysis. Different softwares were used for prediction of target pathways associated with HCC development.

c) Microarray analysis leads to identification of significantly altered [&gt; or &lt; 1.5 fold, p value &lt;0.05] 42 miRNAs in HCC and 65 in LC. Ten common altered miRNAs with high signal intensity were validated in both HBV (10 from each stage) and HCV (7 from each stage) infected tissues and only six miRNAs were successfully validated by qRT-PCR. Subsequently, expression of only two miRNAs, miR-126 and miR142-3p were found significantly higher in HCC plasma compared to asymptomatic control (p&lt;0.05). But expressions of both miRNAs were similar between LC and HCC+LC plasma while it was significantly higher in HCC-LC (p&lt;0.05). Further, AUROC value to discriminate HCC from non-HCC was found higher for miR-126, 0.83 [95% CI (0.74-0.91), p&lt;0.05] with 80% sensitivity and 81% specificity than AFP, which was 0.77 [95% CI (0.68-0.86)] with 72% sensitivity and 87% specificity, while combination achieved highest AUROC of 0.94 [95% CI (0.9-0.99)] with 89% sensitivity and 93% specificity. Moreover, high expression of miR-126 in sample with low AFP [&lt;250ng/ml in 32.6% of HCC (16/49)] and AUROC of 0.896 [95% CI (0.78-1)] with 88% sensitivity and 81% specificity implicates the diagnostic importance of miR-126. To gain insight into the pathophysiological role of miR-126 in HCC development different target prediction programs were used and correlated with gene expression data of HCC from “Oncomine” followed by KEGG pathway analysis which revealed target genes from MAPK, cytokine-cytokine receptor interaction and metabolic pathways.

d) In conclusion, combination of miR-126 with AFP may be a better predictor of HCC in high-risk chronic hepatitis patients and miR-126 alone can show better performance in detection of HCC with low AFP.

Citation Format: Amit Ghosh, Alip Ghosh, Somenath Datta, Debanjali Dasgupta, Soumyajit Das, Sukanta Ray, Subash Gupta, Simanti Datta, Abhijit Chowdhury, Saroj Kant Mohapatra, Soma Banerjee. Hepatic microRNA as biomarker for detection of hepatocellular carcinoma in high-risk chronic Hepatitis B patients. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3969. doi:10.1158/1538-7445.AM2015-3969

Novel point and combo-mutations in the genome of hepatitis B virus-genotype D: characterization and impact on liver disease progression to hepatocellular carcinoma

Background

The contribution of chronic hepatitis B virus (HBV) infection in the pathogenesis of hepatocellular carcinoma (HCC) through progressive stages of liver fibrosis is exacerbated by the acquisition of naturally occurring mutations in its genome. This study has investigated the prevalence of single and combo mutations in the genome of HBV-genotype D from treatment naïve Indian patients of progressive liver disease stages and assessed their impact on the disease progression to HCC.

Methods

The mutation profile was determined from the sequence analysis of the full-length HBV genome and compared with the reference HBV sequences. SPSS 16.0 and R software were used to delineate their statistical significance in predicting HCC occurrence.

Results

Age was identified as associated risk factor for HCC development in chronic hepatitis B (CHB) patients (p≤0.01). Beyond the classical mutations in basal core promoter (BCP) (A1762T/G1764A) and precore (G1862T), persistence of progressively accumulated mutations in enhancer-I, surface, HBx and core were showed significant association to liver disease progression. BCP_T1753C, core_T147C, surface_L213I had contributed significantly in the disease progression to HCC (p<0.05) in HBeAg positive patients whereas precore_T1858C, core_I116L, core_P130Q and preS1_S98T in HBeAg negative patients. Furthermore, the effect of individual mutation was magnified by the combination with A1762T/G1764A in HCC pathogenesis. Multivariate risk analysis had confirmed that core_P130Q [OR 20.71, 95% CI (1.64–261.77), p = 0.019] in B cell epitope and core_T147C [OR 14.58, 95% CI (1.17–181.76), p = 0.037] in CTL epitope were two independent predictors of HCC in HBeAg positive and negative patients respectively.

Conclusions

Thus distinct pattern of mutations distributed across the entire HBV genome may be useful in predicting HCC in high-risk CHB patients and pattern of mutational combinations may exert greater impact on HCC risk prediction more accurately than point mutations and hence these predictors may support the existing surveillance strategies in proper management of the patients.

Distinct distribution pattern of hepatitis B virus genotype C and D in liver tissue and serum of dual genotype infected liver cirrhosis and hepatocellular carcinoma patients

Aims

The impact of co-infection of several hepatitis B virus (HBV) genotypes on the clinical outcome remains controversial. This study has for the first time investigated the distribution of HBV genotypes in the serum and in the intrahepatic tissue of liver cirrhotic (LC) and hepatocellular carcinoma (HCC) patients from India. In addition, the genotype-genotype interplay and plausible mechanism of development of HCC has also been explored.

Methods

The assessment of HBV genotypes was performed by nested PCR using either surface or HBx specific primers from both the circulating virus in the serum and replicative virus that includes covalently closed circular DNA (cccDNA) and relaxed circular DNA (rcDNA) of HBV from the intrahepatic tissue. The integrated virus within the host chromosome was genotyped by Alu-PCR method. Each PCR products were cloned and sequences of five randomly selected clones were subsequently analysed.

Results

HBV/genotype D was detected in the serum of all LC and HCC patients whereas the sequences of the replicative HBV DNA (cccDNA and rcDNA) from the intrahepatic tissue of the same patients revealed the presence of both HBV/genotype C and D. The sequences of the integrated viruses exhibited the solo presence of HBV/genotype C in the majority of LC and HCC tissues while both HBV/genotype C and D clones were found in few patients in which HBV/genotype C was predominated. Moreover, compared to HBV/genotype D, genotype C had higher propensity to generate double strand breaks, ER stress and reactive oxygen species and it had also showed higher cellular homologous-recombination efficiency that engendered more chromosomal rearrangements, which ultimately led to development of HCC.

Conclusions

Our study highlights the necessity of routine analysis of HBV genotype from the liver tissue of each chronic HBV infected patient in clinical practice to understand the disease prognosis and also to select therapeutic strategy.

Effect of resection of localized pancreaticobiliary adenocarcinoma on angiogenic markers and tissue factor related pro-thrombotic and pro-angiogenic activity

In this study, 52 patients were studied to elucidate the relative impact of resection of localized pancreaticobiliary adenocarcinoma (PBC) on circulating factors of tumour-associated angiogenesis e.g. tissue factor bearing microparticles (TFMP) and vascular endothelial growth factor (VEGF) and their clinicopathological significance to angiogenesis markers in cancer tissue from PBC patients. Angiogenesis array analysis on serum samples revealed that surgical resection of tumour lesion in PBC patients affects the levels of a panel of angiogenesis-related molecules, including VEGF that was verified by ELISA to significantly reduce (median & IQR: 1003(369-2000) vs. 457(159-834) pg/ml; p<0.05). Correspondingly, a significant decrease in the angiogenic activity (decreased capillary tube formation; p<0.05) of serum samples after the surgery was also found. Despite a decrease in number of circulating TFMP after surgery, this did not reach statistical significance; there was a significant reduction in pro-coagulant activity (prolonged prothrombin time, p<0.001) post-operatively. In addition, the activity of total microparticles (MP activity assay, p<0.05) was decreased significantly. Immunohistochemical staining of tumour tissue revealed a strong correlation between the microvessel density (MVD) and VEGF expression. Also, higher levels of circulating TFMP or TF related activity (prothrombin time) correlated significantly with TF expression and MVD on tumour tissues from PBC patients. These findings suggest that in pancreaticobiliary adenocarcinoma TF related angiogenesis drivers are equally significant to VEGF ones, raising the clinical question of whether the effectiveness of angiogenesis targeting studies could be improved through the 'dual' targeting of these pathways in PBC.

Abstract LB-71: Carcinogenic significance of integrated hepatitis b viral factors and its genotype in hepatocarcinogenesis

Integration of Hepatitis B Virus (HBV) is one of the major causes underlying Hepatocellular carcinoma (HCC) development. Recent studies revealed that altered expression of multiple cellular genes due to multiple random integration of viral factors lead to development of HCC. The present study aims to identify the carcinogenic significance of integrated HBV genome and its genotype in HCC development.

Host-Viral Junctions were determined in HCC (T) /adjacent tissues (NT) and cirrhotic (-HCC) tissues by sequencing of Alu PCR product followed by sequence blast. Host gene expression was checked by real time PCR. Competition between two coexisting genotypes was studied by replication assay using genotype specific PCR from media and viral core particle isolated from genotype specific plasmid transfected HepG2 cell line. Similarly, each viral genotype mediated DNA damage (γH2aX foci by confocal microscopy), ROS generation (DCFDA quantitation by Facs analysis and ER stress marker GRP78 luciferase assay), homologous recombination efficiency were also compared.

HBV integration was observed in 66.7% of T (8/12), 33.3% (4/12) NT and 75% (6/8) cirrhotic tissue samples in 18, 4 and 8 different locations respectively. These viral integration analysis within or close to several host genes, such as genes involved in differentiation, signaling, stress response, cell cycle, telomere regulations (8/30, 26.7%) etc and most of them showed altered expression. Interestingly, C-terminal truncated HBX which lost its growth suppressive domain were observed more in T (5/8, 62.5%) than NT (2/4, 50%) tissue samples. Most importantly, upon genotype analysis of each five clones in serum and tissue showed genotype C preferentially integrated in coexistence of both C and D genotype as “free virus” in tissue but D genotype observed in circulation. Genotype specific PCR from HBV/C & D cotransfected media showed that in presence of HBV/C, D replicates better than C but HBV/C with high recombination frequency generates more DNA damage and facilitate viral integration.

Thus random integration of HBV in host chromosome causes alterations in oncogenic gene expression and these alterations presumably lead to clonal selection of hepatocyte that acquires a growth advantage and proceeds towards HCC. Genotype of HBV is an important determining factor for HBV integration and liver inury.

Citation Format: Soma Banerjee, Somenath Datta, Shrabasti Roychoudhury, Debanjali Dasgupta, Amit Ghosh, Gaurav Roy, Simanti Datta, Abhijit Chowdhury. Carcinogenic significance of integrated hepatitis b viral factors and its genotype in hepatocarcinogenesis. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr LB-71. doi:10.1158/1538-7445.AM2013-LB-71

Abstract 2306: MicroRNA 199a*: a potent suppressor of tumor metastasis and angiogenesis

The growth of a solid tumor depends on diffusion of nutrients from the tumor microenvironment through vascular system. Angiogenesis, the new blood vessels formation is the primary route by which tumor cells get nutrients as well as exit from primary site and enter into the blood circulation. The proliferation and migration of vascular endothelial cells are triggered by angiogenic growth factors secreted by tumor cells, such as VEGF, TGF-β etc. Recent evidences showed HGF also plays an important role in angiogenesis by enhancing the proliferative activity and intracellular signaling. HGF/its receptor, c-MET and VEGF/VEGFR1 are two independent pathways for angiogenesis and metastasis. Thus detection of a molecule that hits both pathways could be a potent therapeutic agent that could facilitate the inhibition of improved barrier function. Recently mir199a* has been shown to target both CD44 and cMET molecule to block the metastasis in cancer. The present study aim to show that mir199a* also target HGF, the key modulator of the HGF/c-Met signaling cascade in epithelial cells to shut off the mesenchymal transition and VEGFR1 to prevent angiogenesis more effectively.

Luciferase 3’ UTR assay was performed to investigate HGF as a target of mir-199a*. HGF mRNA and protein expression was determined by real time RT-PCR, Western blot analysis in liver stellate cell line LX2 transfected with mir-199a* and HGF shRNA. The cultured media of mir-199a* transfected LX2 cells was used to verify the effect of mir-199a* on HGF induced migration and invasion ability on metastatic cell lines using Boyden chamber assay with or without matrigel coated membrane and angiogenesis by tube formation assay.

The mir-199a* binding site was detected by pictar, target scan analysis of the 3’UTR of HGF and VEGFRs. The binding of mir-199a* to the 3′UTR of HGF and VEGFR1 were confirmed by luciferase assay, mutagenesis and western blotting. Down regulation of HGF protein expression in HGF producing hepatic stellate cell, LX2 was observed by mir-199a*. Addition of LX2 conditioned media transfected with mir199a* to metastatic cell reduces the migration and invasion and also block angiogenesis in endothelial cells.

As Mir-199a* could target HGF/cMET, CD44-cMET and VEGF/VEGFR1 signaling cascade, it could be used as a potential therapeutic target of HCC.

Citation Format: Alip Ghosh, Amit Ghosh, Debanjali Dasgupta, Shrabasti Roychowdhury, Shrabasti Roychowdhury, Simanti Datta, Abhijit Chowdhury, Soma Banerjee. MicroRNA 199a*: a potent suppressor of tumor metastasis and angiogenesis. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2306. doi:10.1158/1538-7445.AM2013-2306

Rare benign pathologies mimicking malignancy: A cautionary tale for Whipple's resections

Benign pathologies demonstrated after a Whipple's resection (pancreatoduodenectomy) for pancreatic and peri-ampullary lesions are relatively uncommon. Here we report two cases where a Whipple's procedure was undertaken for suspected pancreaticobiliary cancer and where the final histology revealed, in each case, a rare benign lesion. The first case confirmed a cholesterol polyp in the distal common bile duct whilst the second case revealed ampullary intramural ectopic gland hyperplasia. Although pre-operative imaging helps in differentiating some benign lesions from malignant lesions, rare benign pathology may still mimic malignant conditions leading to a Whipple's resection.

Hybrid thermoreversible gels from covalent polymers and organogels

This paper reports on experiments intended for investigating the feasibility of preparing hybrid thermoreversible gels from covalent polymers and noncovalent self-assembling pi-conjugated molecules. The formation and the degree of dispersion of these hybrid gels have been studied with polystyrenes of various tacticities and oligo(p-phenylenevinylene) molecules (OPV) in different nonpolar organic solvents. Detailed investigations of the systems have been carried out by DSC, SAXS, and AFM. It is shown that no liquid-liquid phase separation is involved, indicating that the systems are highly compatible, and that the growth of one type of gel does not interfere with the other. These studies reveal that the resultant hybrid gels are composed of the intermingled fibrillar architectures of both gels.

Renal transplantation-anaesthetic experience of 350 cases

SUMMARY

Transplantation provides a near normal life and excellent rehabilitation compared to dialysis and is the preferred method of treatment for end stage renal disease patients. We describe our experiences through a retrospective analysis of anaesthesia management of 350 cases of both living related and cadaveric renal transplantation conducted between Jan 2004 - April 2008 at Jaslok Hospital And Research Center. Areas of our interest include preoperative patient status, fluid management, hemodynamic stability, anaesthesia management, and perioperative complications. Recent advances in surgical techniques; anaesthesia management and immunosuppressive drugs have made renal transplantation sale and predictable. Preoperative patient optimization, intraoperative physiological stability and postoperative care of renal transplant patients have contributed to the success of renal transplant programme in our hospital.

Anaesthesia for renal transplantation: an update

SUMMARY

Attempts at organ transplantation have been made since the 19(th) century. Renal transplantation is the preferred treatment for end stage renal disease. Renal transplant anaesthesia requires a thorough understanding of the metabolic and systemic abnormalities in end stage renal disease, familiarity with transplant medicine and expertise in managing and optimizing these patients for the best possible outcome. Also, the associated co-morbid conditions increase the complexity of anaesthesia, pain management and perioperative morbidity and mortality. Hence, a good perioperative management of these patients includes a multidisciplinary collaboration with well-planned anaesthetic strategies.

Fiberoptic Intubation Using LMA as A Conduit and Cook Airway Catheter as An Exchanger in A Case of Tessier 7 Facial Cleft Syndrome

SUMMARY

Any anaesthesiologist handling a paediatric airway must have a detailed understanding of the differences in airway anatomy, signs and symptoms of airway compromise and common paediatric airway abnormalities. In addition to various equipments needed to manage a difficult airway, there should be a clear plan for evaluation, preparation and management of life threatening complications. We share our experience of successfully managing a difficult airway of a 5 year old child with Tessier 7 facial cleft syndrome. We emphasize the importance of preoperative evaluation, preparation and use of various airway adjuncts.

Quality of life after liver resection for hepatobiliary malignancies

BACKGROUND

Few prospective longitudinal studies have used a validated quality of life (QOL) instrument in patients undergoing liver resection for hepatobiliary malignancy.

METHODS

Patients undergoing liver resection for hepatobiliary tumours in a 1-year period were enrolled. The cancer-specific European Organization for Research and Treatment of Cancer core questionnaire (EORTC QLQ-C30) was completed before operation, and at 6, 12 and 36-48 months after surgery. QOL over time was analysed in relation to several clinical factors.

RESULTS

A total of 103 patients were enrolled. Patient compliance was at least 75 per cent at all stages. Most functional scales and the global QOL scale showed a non-significant trend towards deterioration at 6 months and a return to preoperative level at 12 months. Physical functioning and dyspnoea deteriorated significantly at 6 months (P = 0.020 and P = 0.004 respectively) and did not recover by 12 months (P = 0.002 and P < 0.001 respectively). Pain and fatigue showed clinically significant deterioration over 12 months, which was not statistically significant. Survivors without recurrence at 36-48 months showed better QOL than those with recurrent disease.

CONCLUSION

Major liver resection is associated with acceptable QOL outcomes, and QOL continues to improve in the long term in those without recurrence.

Triangular and self-triangulating cavocavostomy for orthotopic liver transplantation without posterior suture lines: a modified surgical technique

A modified caval preservation technique with the potential for decreased incidence of venous outflow obstruction and haemorrhage.

Cystic duct and Heister's "valves"

The anatomy and physiology of the cystic duct have been relatively neglected by anatomists and the function of the spiral mucosal folds or "valves" of Heister, first described in 1732, remains obscure. The gross and microscopic anatomy of the cystic duct is reviewed together with results from laboratory investigations into the function of the cystic duct and its spirally arranged folds. The duct and spiral folds contain muscle fibers responsive to pharmacologic, hormonal, and neural stimuli. There is, however, no convincing evidence of a discrete muscular sphincter within the duct. Although the cystic duct is unlikely to play a major role in gallbladder filling and emptying, it appears to function as more than a passive conduit. Coordinated, graded muscular activity in the cystic duct in response to hormonal and neural stimuli may facilitate gallbladder emptying. The principal function of the internal spiral folds that are found in man and other animals may be to preserve patency of this narrow, tortuous tube rather than to regulate bile flow.