TRIM35 Interacts with pyruvate kinase isoform M2 to suppress the Warburg effect and tumorigenicity in hepatocellular carcinoma

Tripartite motif-containing protein 35 (TRIM35) is a member of RBCC family, which has a highly conserved order consisting of a RING domain followed by one or two B-Box domains and then a coiled-coil domain. We previously identified TRIM35 as a novel tumor suppressor in human hepatocellular carcinoma (HCC). However, the molecular mechanism that TRIM35 uses to suppress tumorigenicity is largely unknown. Pyruvate kinase isoform M2 (PKM2) has been demonstrated to have a central role in metabolic reprogramming during cancer progression. Phosphorylation of PKM2 tyrosine residue 105 (Y105) regulates PKM2 to provide a metabolic advantage to tumor cells, thereby promoting tumor growth. In the present work, mass spectrometry analysis demonstrated an interaction between TRIM35 and PKM2. Co-IP experiments confirmed that TRIM35 interacts with PKM2 and that the coiled-coil domain is required for such an interaction. Furthermore, the coiled-coil domain mediates decreases in the Warburg effect and in the cell proliferation of HCC cells. In addition, TRIM35 suppresses the tumorigenicity of HCC cells through the blockade of PKM2 Y105 phosphorylation. Collectively, our data reveal a new function for TRIM35, which is to regulate the Warburg effect and tumorigenicity through interaction with PKM2 in HCC.

Structural Insights into the Molecular Recognition between Cerebral Cavernous Malformation 2 and Mitogen-Activated Protein Kinase Kinase Kinase 3

Cerebral cavernous malformation 2 (CCM2) functions as an adaptor protein implicated in various biological processes. By interacting with the mitogen-activated protein kinase MEKK3, CCM2 either mediates the activation of MEKK3 signaling in response to osmotic stress or negatively regulates MEKK3 signaling, which is important for normal cardiovascular development. However, the molecular basis governing CCM2-MEKK3 interaction is largely unknown. Here we report the crystal structure of the CCM2 C-terminal part (CCM2ct) containing both the five-helix domain (CCM2cts) and the following C-terminal tail. The end of the C-terminal tail forms an isolated helix, which interacts intramolecularly with CCM2cts. By biochemical studies we identified the N-terminal amphiphilic helix of MEKK3 (MEKK3-nhelix) as the essential structural element for CCM2ct binding. We further determined the crystal structure of CCM2cts-MEKK3-nhelix complex, in which MEKK3-nhelix binds to the same site of CCM2cts for CCM2ct intramolecular interaction. These findings build a structural framework for understanding CCM2ct-MEKK3 molecular recognition.

Experimental study of survival of pedicled perforator flap with flow-through and flow-end blood supply

BACKGROUND

Flap viability after transfer depends on blood flow from the arterial blood supply below the fascia. This study evaluated survival of a pedicle flap with a perforator lateral branch and flow-through blood supply, compared with that of a flap with a flow-end blood supply and perforator terminal branch.

METHODS

Forty Sprague-Dawley rats, 20 in each group, were assigned to transfer of a superficial epigastric artery pedicle island flap with a flow-through or flow-end configuration of blood supply. Laser Doppler imaging was used to evaluate flap perfusion 2 h, 3 days and 5 days after surgery. The rats were killed on day 5, and lead oxide-gelatine-enhanced flap angiography and histology with haematoxylin and eosin staining was performed. Dorsal midline tissue was excised for quantification of vascular endothelial growth factor by western blot assay.

RESULTS

On day 5 after surgery, the flow-through group exhibited a significantly greater mean(s.d.) flap survival area (97·8(3·5) versus 80·8(10·2) per cent; P = 0·003), microvascular density (303(19) versus 207(41) per mm(2) ; P < 0·001) and perfusion (8·64(0·14) versus 5·95(0·14) perfusion units; P < 0·001) than the flow-end group. The flow-through group exhibited more angiosomes connected by dilated vascular anastomoses between the skin and subcutaneous fasciae.

CONCLUSION

The flow-through blood supply improved pedicle perforator flap survival. Surgical relevance Perforator flap failure is mainly the result of impaired blood supply, as a flow-end blood configuration is nourished only by the perforator terminal branch of the artery. This work showed that the flow-through blood supply nourished by the perforator lateral branch improved flap survival, with dilatation of collateral vascular anastomoses and increased neoangiogenesis. The use of a flow-through configuration improves perforator flap survival and could therefore minimize morbidity resulting from flap necrosis.

A new strategy for complete identification of sea buckthorn cultivars by using random amplified polymorphic DNA markers

DNA fingerprinting is both a popular and important technique with several advantages in plant cultivar identification. However, this technique has not been used widely and efficiently in practical plant identification because the analysis and recording of data generated from fingerprinting and genotyping are tedious and difficult. We developed a novel approach known as a cultivar identification diagram (CID) strategy that uses DNA markers to separate plant individuals in a more efficient, practical, and referable manner. A CID was manually constructed and a polymorphic marker was generated from each polymerase chain reaction for sample separation. In this study, 67 important sea buckthorn cultivars cultivated in China were successfully separated with random amplified polymorphic DNA markers using the CID analysis strategy, with only seven 11-nucleotide primers employed. The utilization of the CID of these 67 sea buckthorn cultivars was verified by identifying 2 randomly chosen groups of cultivars among the 67 cultivars. The main advantages of this identification strategy include fewer primers used and separation of all cultivars using the corresponding primers. This sea buckthorn CID was able to separate any sea buckthorn cultivars among the 67 studied, which is useful for sea buckthorn cultivar identification, cultivar-right-protection, and for the sea buckthorn nursery industry in China.

Dendritic cell CD83 homotypic interactions regulate inflammation and promote mucosal homeostasis

Dendritic cells (DCs) form an extensive network in the intestinal lamina propria, which orchestrates the mucosal immune response. Alterations in DC function can predispose to inflammatory bowel disease, although by unknown mechanisms. We show that CD83, a highly regulated DC cell surface protein, modulates the immune response to prevent colitis. Mice with a conditional knockout of CD83 in DCs develop exacerbated colitis following dextran sodium sulfate challenge, whereas mucosal overexpression of CD83 inhibits DC inflammatory response and protects against colitis. These CD83 perturbations can be modeled in vitro where we show that CD83 homotypic interaction occurs via cell-cell contact and inhibits pro-inflammatory responses. CD83 knockdown or cytoplasmic truncation abrogates the effects of homotypic binding. We demonstrate that CD83 homotypic interaction regulates DC activation via the mitogen-activated protein kinase pathway by inhibiting p38α phosphorylation. Our findings indicate that CD83 homotypic interactions regulate DC activation and promote mucosal homeostasis.

Preconditioning donor livers with cromolyn or compound 48/80 prolongs recipient survival in a rat orthotopic liver transplantation model

BACKGROUND

Acute rejection (AR) remains a challenge in organ transplantation. Preconditioning donor organs can reduce AR and prolong survival. Whether preconditioning with cromolyn (CRM), a mast cell (MC) stabilizer, or compound 48/80 (CMP 48/80), a MC degranulator, can alleviate AR and prolong survival has not been studied.

METHODS

We used the male-DA-to-female-Lewis-rat orthotopic liver transplantation (OLT) model. Donors were preconditioned with CRM in a MC stabilizing way (CRM group) or CMP 48/80 in a MC depleting way (CMP 48/80 group). Rats preconditioned with phosphate-buffered saline were used as controls (PBS group). After preconditioning, OLT surgeries were carried out. OLT male-Lewis-to-female-Lewis-rats were used as the syngeneic group (syngeneic group).

RESULTS

Rats in the PBS group developed AR rapidly and died at 7.40 ± 1.14 days. Rats in the CRM and CMP 48/80 groups had significantly slower rejections and died at day 17.40 ± 1.67 or 14.20 ± 2.28, respectively (P < .05). Rats in the syngeneic group survived more than 60 days. Rejection activity indexes (RAIs) and liver functions were all alleviated through CRM or CMP 48/80 preconditioning. Interferon-γ messenger RNA (mRNA) expressions were reduced and interleukin-10 mRNA levels were higher in allografts in the CRM and CMP 48/80 groups, compared with the PBS group. These were confirmed by testing serum interferon-γ and interlerkin-10.

CONCLUSION

Preconditioning donor livers with CRM or CMP 48/80 can reduce AR and prolong survival of recipients after OLT.

Size dependent magnetic hyperthermia of octahedral Fe3O4 nanoparticles

Octahedral Fe₃O₄ nanoparticles show a wide size range for high SAR values to be used as an excellent thermal seed for magnetic hyperthermia cancer treatment.

Slow and steady cell shrinkage reduces osmotic stress in bovine and murine oocyte and zygote vitrification

STUDY QUESTION

Does the use of a new cryoprotectant agent (CPA) exchange protocol designed to minimize osmotic stress improve oocyte or zygote vitrification by reducing sublethal cryodamage?

SUMMARY ANSWER

The use of a new CPA exchange protocol made possible by automated microfluidics improved oocyte and zygote vitrification with superior morphology as indicated by a smoother cell surface, higher sphericity, higher cytoplasmic lipid retention, less cytoplasmic leakage and higher developmental competence compared with conventional methods.

WHAT IS KNOWN ALREADY

The use of more 'steps' of CPA exposure during the vitrification protocol increases cryosurvival and development in the bovine model. However, such an attempt to eliminate osmotic stress is limited by the practicality of performing numerous precise pipetting steps in a short amount of time.

STUDY DESIGN, SIZE, DURATION

Murine meiotically competent germinal vesicle intact oocytes and zygotes were harvested from the antral follicles in ovaries and ampulla, respectively. Bovine ovaries were obtained from a local abattoir at random stages of the estrous cycle. A total of 110 murine oocytes, 802 murine zygotes and 52 bovine oocytes were used in this study.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Microfluidic devices were fabricated using conventional photo- and soft-lithography. CPAs used were 7.5% ethylene glycol (EG) and 7.5% dimethyl sulfoxide (DMSO) for equilibration solution and 15% EG, 15% DMSO and 0.5 M sucrose for vitrification solution. End-point analyses include mathematical modeling using Kedem-Katchalsky equations, morphometrics assessed by conventional and confocal microscopy, cytoplasmic lipid quantification by nile red staining, cytoplasmic leakage quantification by fluorescent dextran intercalation and developmental competence analysis by 96 h embryo culture and blastomere quantification.

MAIN RESULTS AND THE ROLE OF CHANCE

The automated microfluidics protocol decreased the shrinkage rate of the oocyte and zygote by 13.8 times over its manual pipetting alternative. Oocytes and zygotes with a lower shrinkage rate during CPA exposure experienced less osmotic stress resulting in better morphology, higher cell quality and improved developmental competence. This microfluidic procedure resulted in murine zygotes with a significantly smoother cell surface (P < 0.001), more spherical cellular morphology (P < 0.001), increased cytoplasmic lipid retention in vitrified and warmed bovine oocytes (P < 0.01), decreased membrane perforations and cytoplasmic leakage in CPA-exposed murine zygotes (P < 0.05) and improved developmental competence of vitrified and warmed murine zygotes (P < 0.05) than CPA exposure using the current clinically used manual pipetting method.

LIMITATIONS, REASONS FOR CAUTION

It is necessary to design the microfluidic device to be more user-friendly for widespread use.

WIDER IMPLICATIONS OF THE FINDINGS

The theory and approach of eliminating osmotic stress by decreasing shrinkage rate is complementary to the prevalent osmotic stress theory in cryobiology which focuses on a minimum cell volume at which the cells shrink. The auto-microfluidic protocol described here has immediate applications for improving animal and human oocyte, zygote and embryo cryopreservation. On a fundamental level, the clear demonstration that at the same minimum cell volume, cell shrinkage rate affects sublethal damage should be broadly useful for cryobiology.

STUDY FUNDING/COMPETING INTERESTS

This project was funded by the National Institutes of Health and the University of Michigan Reproductive Sciences Program. The authors declare no conflicts of interest.

Intrinsic and interfacial effect of electrode metals on the resistive switching behaviors of zinc oxide films

Exploring the role of electrode metals on the resistive switching properties of metal electrode/oxide/metal electrode sandwiched structures provides not only essential information to understand the underlying switching mechanism of the devices, but also useful guidelines for the optimization of the switching performance. A systematic study has been performed to investigate the influence of electrodes on the resistive switching characteristics of zinc oxide (ZnO) films in this contribution, in terms of both the intrinsic and interfacial effects. It has been found that the low-resistance state resistances (Ω(LRS)) of all the investigated devices are below 50 Ω, which can be attributed to the formation of highly conductive channels throughout the ZnO films. On the other hand, the high-resistance state resistances (Ω(HRS)) depend on the electronegativity and ionic size of the employed electrode metals. Devices with electrode metals of high electronegativity and large ionic size possess high Ω(HRS) values, while those with electrode metals of low electronegativity and small ionic size carry low Ω(HRS) values. A similar trend of the set voltages has also been observed, while the reset voltages are all distributed in a narrow range close to ±0.5 V. Moreover, the forming voltages of the switching devices strongly depend on the roughness of the metal/ZnO and/or ZnO/metal interface. The present work provides essential information for better understanding the switching mechanism of zinc oxide based devices, and benefits the rational selection of proper electrode metals for the device performance optimization.

Structural and mechanistic insights into NDM-1 catalyzed hydrolysis of cephalosporins

Cephalosporins constitute a large class of β-lactam antibiotics clinically used as antimicrobial drugs. New Dehli metallo-β-lactamase (NDM-1) poses a global threat to human health as it confers on bacterial pathogen resistance to almost all β-lactams, including penicillins, cephalosporins, and carbapenems. Here we report the first crystal structures of NDM-1 in complex with cefuroxime and cephalexin, as well as NMR spectra monitoring cefuroxime and cefixime hydrolysis catalyzed by NDM-1. Surprisingly, cephalosporoate intermediates were captured in both crystal structures determined at 1.3 and 2.0 Å. These results provide detailed information concerning the mechanism and pathways of cephalosporin hydrolysis. We also present the crystal structure and enzyme assays of a D124N mutant, which reveals that D124 most likely plays a more structural than catalytic role.

Inflammatory caspases are innate immune receptors for intracellular LPS

The murine caspase-11 non-canonical inflammasome responds to various bacterial infections. Caspase-11 activation-induced pyroptosis, in response to cytoplasmic lipopolysaccharide (LPS), is critical for endotoxic shock in mice. The mechanism underlying cytosolic LPS sensing and the responsible pattern recognition receptor are unknown. Here we show that human monocytes, epithelial cells and keratinocytes undergo necrosis upon cytoplasmic delivery of LPS. LPS-induced cytotoxicity was mediated by human caspase-4 that could functionally complement murine caspase-11. Human caspase-4 and the mouse homologue caspase-11 (hereafter referred to as caspase-4/11) and also human caspase-5, directly bound to LPS and lipid A with high specificity and affinity. LPS associated with endogenous caspase-11 in pyroptotic cells. Insect-cell purified caspase-4/11 underwent oligomerization upon LPS binding, resulting in activation of the caspases. Underacylated lipid IVa and lipopolysaccharide from Rhodobacter sphaeroides (LPS-RS) could bind to caspase-4/11 but failed to induce their oligomerization and activation. LPS binding was mediated by the CARD domain of the caspase. Binding-deficient CARD-domain point mutants did not respond to LPS with oligomerization or activation and failed to induce pyroptosis upon LPS electroporation or bacterial infections. The function of caspase-4/5/11 represents a new mode of pattern recognition in immunity and also an unprecedented means of caspase activation.

Clinical risk factors for depressive symptoms in patients with epilepsy

BACKGROUND AND AIMS

To investigate the relationships between demographic data, seizure-related factors, anti-epileptic drugs (AEDs) taking, and depressive symptoms in patients with epilepsy (PWE), determining the major clinical risk factors of depression.

METHODS

Patients with epilepsy who visited our epilepsy clinic from 2010 to 2012 were included. The clinical data were collected, and Hamilton Depression Rating Scale (HAMD), National Hospital Seizure Severity Scale (NHS3) and Pittsburgh Sleep Quality Index (PSQI) were evaluated.

RESULTS

A total of 116 PWE were recruited. They were divided into three groups. Age, duration of epilepsy, percentages of patients with partial seizures, history of status epilepticus (SE), using topiramate (TPM) or clonazepam (CZP), and using greater than or equal to 2 types of AEDs were all significantly higher in patients with moderate depressive symptoms than patients without depression. HAMD scores were positively correlated with age, duration of epilepsy, and the number of AEDs taking, respectively. PSQI scores were positively correlated with HAMD scores in patients with depressive symptoms. Age greater than 35 years, females, having partial seizures, history of SE, and using TPM were independent predictors of depressive symptoms in PWE by regression analysis.

CONCLUSIONS

Age greater than 35 years, females, having partial seizures, history of SE, and using TPM might become risk factors for depressive symptoms in PWE.

Periaortic fat and cardiovascular risk: a comparison of high-risk older adults and age-matched healthy controls

Objective

Fat accumulation around the heart and aorta may impact cardiovascular (CV) health. The purpose of this study was to conduct a systematic investigation to examine potential associations of these fat depots with risk factors for CV events, which has not been done before.

Methods

Pericardial fat, periaortic fat around the ascending aorta (AA), descending aorta (DA) and aortic arch, and abdominal subcutaneous and visceral fat were measured by MRI in older adults with (n=385, 69±8 years, 52% female) and without (n=50, 69±8 years, 58% female) risk factors for a CV event.

Results

Individuals with CV risk factors exhibited greater fat volumes across all fat depots compared to those without risk factors. In analysis of covariance accounting for age, gender, race/ethnicity, diabetes, hypertension, coronary artery disease, smoking, and BMI, individuals with risk factors possessed higher epicardial, pericardial, AA, DA, and abdominal visceral fat (p<0.05). When matched one-to-one on age, gender, race/ethnicity, and BMI, AA and DA fat were higher in those with versus without CV risk factors (p<0.01).

Conclusions

Older adults with a high risk for CV events have greater periaortic fat than low-risk adults, even after accounting for BMI. More studies are needed to determine whether greater periaortic fat predicts future CV events.

The impact of sarcopenia on a physical activity intervention: the Lifestyle Interventions and Independence for Elders Pilot Study (LIFE-P)

OBJECTIVE

To determine if sarcopenia modulates the response to a physical activity intervention in functionally limited older adults.

DESIGN

Secondary analysis of a randomized controlled trial.

SETTING

Three academic centers.

PARTICIPANTS

Elders aged 70 to 89 years at risk for mobility disability who underwent dual-energy x-ray absorptiometry (DXA) for body composition at enrollment and follow-up at twelve months (N = 177).

INTERVENTION

Subjects participated in a physical activity program (PA) featuring aerobic, strength, balance, and flexibility training, or a successful aging (SA) educational program about healthy aging.

MEASUREMENTS

Sarcopenia as determined by measuring appendicular lean mass and adjusting for height and total body fat mass (residuals method), Short Physical Performance Battery score (SPPB), and gait speed determined on 400 meter course.

RESULTS

At twelve months, sarcopenic and non-sarcopenic subjects in PA tended to have higher mean SPPB scores (8.7±0.5 and 8.7±0.2 points) compared to sarcopenic and non-sarcopenic subjects in SA (8.3±0.5 and 8.4±0.2 points, p = 0.24 and 0.10), although the differences were not statistically significant. At twelve months, faster mean gait speeds were observed in PA: 0.93±0.4 and 0.95±0.03 meters/second in sarcopenic and non-sarcopenic PA subjects, and 0.89±0.4 and 0.91±0.03 meters/second in sarcopenic and non-sarcopenic SA subjects (p = 0.98 and 0.26), although not statistically significant. There was no difference between the sarcopenic and non-sarcopenic groups in intervention adherence or number of adverse events.

CONCLUSION

These data suggest that older adults with sarcopenia, who represent a vulnerable segment of the elder population, are capable of improvements in physical performance after a physical activity intervention.

Structural insights into the unique single-stranded DNA-binding mode of Helicobacter pylori DprA

Natural transformation (NT) in bacteria is a complex process, including binding, uptake, transport and recombination of exogenous DNA into the chromosome, consequently generating genetic diversity and driving evolution. DNA processing protein A (DprA), which is distributed among virtually all bacterial species, is involved in binding to the internalized single-stranded DNA (ssDNA) and promoting the loading of RecA on ssDNA during NTs. Here we present the structures of DNA_processg_A (DprA) domain of the Helicobacter pylori DprA (HpDprA) and its complex with an ssDNA at 2.20 and 1.80 Å resolutions, respectively. The complex structure revealed for the first time how the conserved DprA domain binds to ssDNA. Based on structural comparisons and binding assays, a unique ssDNA-binding mode is proposed: the dimer of HpDprA binds to ssDNA through two small, positively charged binding pockets of the DprA domains with classical Rossmann folds and the key residue Arg52 is re-oriented to ‘open’ the pocket in order to accommodate one of the bases of ssDNA, thus enabling HpDprA to grasp substrate with high affinity. This mode is consistent with the oligomeric composition of the complex as shown by electrophoretic mobility-shift assays and static light scattering measurements, but differs from the direct polymeric complex of Streptococcus pneumoniae DprA–ssDNA.

Biochemical and structural insights into RNA binding by Ssh10b, a member of the highly conserved Sac10b protein family in Archaea

Proteins of the Sac10b family are highly conserved in Archaea. Ssh10b, a member of the Sac10b family from the hyperthermophilic crenarchaeon Sulfolobus shibatae, binds to RNA in vivo. Here we show that binding by Ssh10b destabilizes RNA secondary structure. Structural analysis of Ssh10b in complex with a 25-bp RNA duplex containing local distortions reveals that Ssh10b binds the two RNA strands symmetrically as a tetramer with each dimer bound asymmetrically to a single RNA strand. Amino acid residues involved in double-stranded RNA binding are similar, but non-identical, to those in dsDNA binding. The dimer-dimer interaction mediated by the intermolecular β-sheet appears to facilitate the destabilization of base pairing in the secondary structure of RNA. Our results suggest that proteins of the Sac10b family may play important roles in RNA transactions requiring destabilization of RNA secondary structure in Sulfolobus.

Immunomodulatory and anti-inflammatory properties of artesunate in experimental colitis

BACKGROUND

Inflammatory bowel disease is a chronic and idiopathic gastrointestinal inflammation mediated by disregulated immune responses. Artemisinin (a chemical from a traditional Chinese herbal medicine Artemisia annua L.) and its derivatives have been proven to exhibit anti-inflammatory and immunomodulatory effects in the treatment of systemic lupus erythematosus and rheumatoid arthritis with low side-effects. This study is aimed to evaluate the potential therapeutic value of artesunate for inflammatory bowel disease.

METHODS

Murine colitis was induced by either oral administration of dextran sulfate sodium salt (DSS) or intrarectal delivery of 2,4,6- trinitrobenzene sulfonic acid (TNBS) or oxazolone. Mice were treated with artesunate (150mg/kg/day). Peritoneal macrophages were stimulated with lipopolysaccharide (LPS) in the presence or absence of artesunate. Changes in cytokines or proteins of interests were analyzed by enzyme-linked immunosorbent assay (ELISA) or SDS-PAGE/Western blot.

RESULTS

Artesunate significantly ameliorated DSS colitis and TNBS colitis (but not oxazolone colitis), including reduced weight loss and disease activity, as well as macroscopic and microscopic colonic injury. The expression of NF-κBp65 and p-IκB-α were reduced in artesunate treated TNBS colitis compared with untreated. The levels of IFN-γ, IL-17, and TNF-α were significantly decreased in artesunate treated TNBS colitis or DSS colitis. Furthermore, in vitro artesunate treatment significantly inhibited TNF-α production by LPS-activated macrophages.

CONCLUSIONS

Artesunate suppresses TNF-α expression in vitro and in vivo as well as T-helper (Th)1/Th17 responses in TNBS colitis model. Our data suggest a novel clinical application of artesunate as a potential therapy for Crohn's disease.

Structural basis of the novel S. pneumoniae virulence factor, GHIP, a glycosyl hydrolase 25 participating in host-cell invasion

Pathogenic bacteria produce a wide variety of virulence factors that are considered to be potential antibiotic targets. In this study, we report the crystal structure of a novel S. pneumoniae virulence factor, GHIP, which is a streptococcus-specific glycosyl hydrolase. This novel structure exhibits an α/β-barrel fold that slightly differs from other characterized hydrolases. The GHIP active site, located at the negatively charged groove in the barrel, is very similar to the active site in known peptidoglycan hydrolases. Functionally, GHIP exhibited weak enzymatic activity to hydrolyze the PNP-(GlcNAc)5 peptidoglycan by the general acid/base catalytic mechanism. Animal experiments demonstrated a marked attenuation of S. pneumoniae-mediated virulence in mice infected by ΔGHIP-deficient strains, suggesting that GHIP functions as a novel S. pneumoniae virulence factor. Furthermore, GHIP participates in allowing S. pneumoniae to colonize the nasopharynx and invade host epithelial cells. Taken together, these findings suggest that GHIP can potentially serve as an antibiotic target to effectively treat streptococcus-mediated infection.

Complications of thermal ablation of hepatic tumours: comparison of radiofrequency and microwave ablative techniques

AIM

To investigate the common complications of thermal ablation of liver tumours using both radiofrequency ablation (RFA) and microwave ablation (MWA) techniques, and to compare the safety of these two procedures.

MATERIALS AND METHODS

This retrospective study protocol was approved by the institution's ethics committee to allow investigators to review existing patient medical records. A total of 879 patients with hepatic tumours underwent thermal ablation; 323 patients underwent RFA and 556 underwent MWA. The complications of the RFA and MWA techniques were compared.

RESULTS

A total of 1030 thermal ablation sessions was performed in 879 patients with a total of 1652 tumours. Three hundred and twenty-three patients with 562 tumours received a total of 376 RFA sessions with an average of 1.16 ± 0.48 sessions per patient. The other 556 patients with 1090 tumours received a total of 654 MWA with an average 1.18 ± 0.51 sessions per patient. The mortality rates were 0.31% (1/323) and 0.36% (2/556) in RFA and MWA group. In RFA and MWA group, the major complication rates were 3.5% (13/376) and 3.1% (20/654), meanwhile the minor complication rates were 5.9% (22/376) and 5.7% (37/654). There was no statistically significant difference in the mortality rates, major complications, and minor complications between the RFA and MWA groups (p > 0.05).

CONCLUSIONS

Thermal ablation therapy in the treatment of liver cancers is relatively safe with low mortality and a low incidence of serious complications. The types and incidences of complications caused by RFA and MWA are similar and comparable for safety consideration in clinical settings.

A retrospective study of different treatments of limited-stage small-cell esophageal carcinoma and associated prognostic factor analysis

Primary, small-cell esophageal carcinoma (SCEC) is a rare but highly malignant tumor. Due to lack of randomized, controlled, prospective studies, there are currently no unified treatment modalities for SCEC. This study retrospectively analyzed the outcomes of different treatments and prognostic factors that influence overall survival in patients with limited-stage SCEC. The study included 106 patients pathologically diagnosed with limited-stage SCEC at Huai'an First People's Hospital, Nanjing Medical University (Huai'an, China), between 1998 and 2007. There were 66 males and 40 females, with a median age of 58 years (range: 45-77 years). Fourteen patients received surgery alone, 42 received surgery and postoperative chemotherapy, 11 received radiotherapy alone, and 39 received concurrent chemoradiotherapy. Combined modality treatment with and without chemotherapy yielded 5-year survival rates (5YSRs) of 27.2% and 0%, respectively. Associated median survival times were 22 months and 11 months, respectively, with a hazard ratio (HR) of 2.30 (95% confidence interval [CI]: 1.42-3.73, P = 0.001). Among patients treated with surgery plus postoperative chemotherapy or with concurrent chemoradiotherapy, the 5YSRs were 31.0% and 23.1%, respectively. Median survival times were 26 months and 18 months, with an HR of 1.25 (95% CI: 0.75-2.09, P = 0.725). Multivariate survival analysis using Cox regression model showed that chemotherapy was a positive independent prognostic factor for SCEC (HR 2.92, 95% CI: 1.25-6.80). Chemotherapy-based combined modality treatment appears to increase the long-term survival of patients with limited-stage SCEC. Similar overall survival rates results are achieved with surgery combined with chemotherapy as with concurrent chemoradiotherapy, with chemotherapy being an independent prognostic factor. Randomized, controlled, prospective studies are needed to identify optimal chemotherapy regimens for treating SCEC.

Abstract P6-04-26: Tamoxifen may block estrogen induced secretion of certain cytokines to interrupt tumor associated macrophage infiltration in breast cancer

The role of tumor microenvironment during the initiation and progression of breast cancer is now realized to be of critical importance, both for understanding of the fundamental cancer biology and exploiting relatively new mechanism for breast cancer metastasis. Macrophage is a one of the most common components in the breast cancer microenvironment. Normally, the macrophage in tumor microenvironment is referred to tumor associated macrophage (TAM), which shares some attributes of alternatively activated macrophage. Many pre-clinical and clinical studies demonstrate an inverse correlation between TAM infiltration and patients' prognosis indicating a macrophage supporting role for tumor progression. It is well documented that selective patients with breast cancer can benefit from anti-estrogen therapy. However, the mechanisms involved are still not fully elucidated. Our previous study indicates that highly tumorigenic breast cancer cell line MDA-MB-231 can educate monocyte differentiation into alternatively activated macrophage, while weakly tumorigenic cell line MCF-7 (without estrogen supplementation) can not. In the present study, we explored the effects of estrogen and tamoxifen on the secreting of certain cytokines, which are required for monocyte chemotaxis and differentiation. Breast cancer cell lines with different estrogen receptor status were applied to estimate the level of cytokines (IL4, IL6, M-CSF, GM-CSF, and MCP-1) before and after cultured with 17β-estradiol, tamoxifen or both. We found that weakly invasive breast cancer cell lines (MCF-7, T47D, MDA-MB-468, and SKBR3) generally expressed lower levels of such cytokines compared with highly invasive breast cancer cell lines (MDA-MB-231, MDA-MB-231-BO, MDA-MB-231 HM, Bcap 37, BT549, and Hs578T) at baseline. However, the discrepancies could be compensated partially by exposure to 10nM 17β-estradiol in estrogen receptor (ER) positive cell lines (MCF-7 and T47D). Moreover, the compensation was substantially blocked by 2μM tamoxifen. On the contrary, tamoxifen, alone, didn't affect the secretion of such cytokines mentioned above in vitro. Based on these findings, we tentatively concluded that some patients with ER positive breast cancers benefiting from anti-estrogen therapy may partially attributes to blocking monocyte differentiation into TAM, which destroyed the tumor microenvironment. These findings suggest the future possibility of using TAM as a novel therapeutic target in patients with anti-estrogen resistance and primary triple-negative breast cancers (TNBC) with no effectively therapeutic measures nowadays, which are defined by lack of estrogen receptor, progesterone receptor and ERBB2 gene amplification, representing approximately 16% of all breast cancers.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-04-26.

Cationic-vacancy-induced room-temperature ferromagnetism in transparent, conducting anatase Ti1-xTaxO2 (x~0.05) thin films

We report room-temperature ferromagnetism (FM) in highly conducting, transparent anatase Ti(1-x)Ta(x)O(2) (x∼0.05) thin films grown by pulsed laser deposition on LaAlO(3) substrates. Rutherford backscattering spectrometry (RBS), X-ray diffraction, proton-induced X-ray emission, X-ray absorption spectroscopy (XAS) and time-of-flight secondary-ion mass spectrometry indicated negligible magnetic contaminants in the films. The presence of FM with concomitant large carrier densities was determined by a combination of superconducting quantum interference device magnetometry, electrical transport measurements, soft X-ray magnetic circular dichroism (SXMCD), XAS and optical magnetic circular dichroism, and was supported by first-principles calculations. SXMCD and XAS measurements revealed a 90 per cent contribution to FM from the Ti ions, and a 10 per cent contribution from the O ions. RBS/channelling measurements show complete Ta substitution in the Ti sites, though carrier activation was only 50 per cent at 5 per cent Ta concentration, implying compensation by cationic defects. The role of the Ti vacancy (V(Ti)) and Ti(3+) was studied via XAS and X-ray photoemission spectroscopy, respectively. It was found that, in films with strong FM, the V(Ti) signal was strong while the Ti(3+) signal was absent. We propose (in the absence of any obvious exchange mechanisms) that the localized magnetic moments, V(Ti) sites, are ferromagnetically ordered by itinerant carriers. Cationic-defect-induced magnetism is an alternative route to FM in wide-band-gap semiconducting oxides without any magnetic elements.

Defect mediated photocatalytic decomposition of 4-chlorophenol on epitaxial rutile thin films under visible and UV illumination

We show that pure rutile TiO(2) can be photo-responsive even under low energy visible light after annealing in vacuum where we envisage that the point defects, i.e. oxygen vacancies and titanium interstitials, serve an important role. In this study, single crystal rutile films were grown by the pulsed laser deposition technique and then vacuum annealed under different oxygen pressures to introduce defects into their lattices. 4-chlorophenol was selected as a model material and decomposed by the annealed TiO(2) films where the maximum photocatalytic reaction rate constants were determined as 0.0107 and 0.0072 min(-1) under UV and visible illumination. Epitaxial growth along the [200] direction was confirmed by φ-scan and 2θ-scan XRD and the epitaxial relationship between the rutile film and the c-sapphire substrate was explained as (100)[010](R) [parallel] (0001)[12[combining overline]10](S). The formation of atomically sharp interfaces and the epitaxial growth were ascertained by annular dark-field STEM imaging. Based on the XPS, UV-vis and PL spectroscopy results, it was found that the defect concentration increased after annealing under lower pressures, e.g. 5 × 10(-6) Torr. In contrast, more perfect crystals were obtained when the films were annealed under high oxygen pressures, namely 5 × 10(1) Torr. The morphology of the films was also investigated by employing an AFM technique. It was observed that increase of the annealing pressure results in the formation of larger grains. It was also found that the electrical resistivity of the rutile films strongly increased by about three orders of magnitude when the annealing pressure increased from 5 × 10(-4) to 5 × 10(1) Torr.

Multilayered mucoadhesive hydrogel films based on thiolated hyaluronic acid and polyvinylalcohol for insulin delivery

A multilayered hydrogel film system based on hyaluronic acid-cysteamine (HA-Cym) and polyvinylalcohol (PVA) was fabricated. It contained a drug-impermeable backing layer, a supporting layer preventing direct contact between the loaded drug and the backing layer, a drug-loading layer and a mucoadhesive layer. Scanning electron microscopy demonstrated the presence of the distinct layers. The composition and preparation procedure of the films influenced their mucoadhesion, swelling, in vitro release of insulin and loaded insulin stability. Vacuum drying and crosslinked PVA with glutaraldehyde might reduce mucoadhesion, and they partially decreased the bioactivity of loaded insulin. Lyophilized hydrogel film with uncrosslinked PVA as a mucoadhesive layer possessed high mucoadhesion and showed no influence on the bioactivity of loaded insulin. The application of vacuum-dried PVA-crosslinked HA-Cym/PVA hydrogel film as a drug-impermeable backing layer would provide a controllable unidirectional insulin release. Therefore, such a multilayered hydrogel film system could be a promising mucoadhesive delivery system for controlled macromolecular drug release.