Ajuba inhibits hepatocellular carcinoma cell growth via targeting of β-catenin and YAP signaling and is regulated by E3 ligase Hakai through neddylation

BACKGROUND

Aberrant activation of β-catenin and Yes-associated protein (YAP) signaling pathways has been associated with hepatocellular carcinoma (HCC) progression. The LIM domain protein Ajuba regulates β-catenin and YAP signaling and is implicated in tumorigenesis. However, roles and mechanism of Ajuba expression in HCC cells remain unclear. The E3 ligase Hakai has been shown to interact with other Ajuba family members and whether Hakai interacts and regulates Ajuba is unknown.

METHODS

HCC cell lines stably depleted of Ajuba or Hakai were established using lentiviruses expressing shRNAs against Ajuba or Hakai. The effects of Ajuba on HCC cells were determined by a number of cell-based analyses including anchorage-independent growth, three dimension cultures and trans-well invasion assay. In vivo tumor growth was determined in a xenograft model and Ajuba expression in tumor sections was examined by immunohistochemistry. Co-immunoprecipitation, confocal microscopy and immunoblot assay were used to examine the expression and interaction between Ajuba and Hakai.

RESULTS

Depletion of Ajuba in HCC cells significantly enhanced anchorage-independent growth, invasion, the formation of spheroids and tumor growth in a xenograft model, suggesting a tumor suppressor function for Ajuba in HCC. Mechanistically, Ajuba depletion triggered E-cadherin loss and β-catenin translocation with increased Cyclin D1 levels. In addition, depletion of Ajuba upregulated the levels of YAP and its target gene CYR61. Furthermore, siRNA-mediated knockdown of either β-catenin or YAP attenuated the pro-tumor effects by Ajuba depletion on HCC cells. Notably, Ajuba stability in HCC cells was regulated by Hakai, an E3 ligase for E-cadherin. Hakai interacted with Ajuba via its HYB domain and induced Ajuba neddylation, which was antagonized by the neddylation inhibitor, MLN4924, but not MG132. We further show that overexpression of Hakai in HCC cells markedly increased anchorage-independent growth, spheroid-formation ability and tumor growth in xenografts whereas Hakai depletion resulted in these opposite effects, indicating an oncogenic role for Hakai in HCC. Hakai also induced β-catenin translocation with increased levels of Cyclin D1.

CONCLUSIONS

Our data suggest a role for Ajuba and Hakai in HCC, and uncover the mechanism underlying the regulation of Ajuba stability.

A systematic review of the relationship between the distributions of aggrecan gene VNTR polymorphism and degenerative disc disease/osteoarthritis

Objectives

Degenerative disc disease (DDD) and osteoarthritis (OA) are relatively frequent causes of disability amongst the elderly; they constitute serious socioeconomic costs and significantly impair quality of life. Previous studies to date have found that aggrecan variable number of tandem repeats (VNTR) contributes both to DDD and OA. However, current data are not consistent across studies. The purpose of this study was to evaluate systematically the relationship between aggrecan VNTR, and DDD and/or OA.

Methods

This study used a highly sensitive search strategy to identify all published studies related to the relationship between aggrecan VNTR and both DDD and OA in multiple databases from January 1996 to December 2016. All identified studies were systematically evaluated using specific inclusion and exclusion criteria. Cochrane methodology was also applied to the results of this study.

Results

The final selection of seven studies was comprehensively evaluated and includes results for 2928 alleles. The most frequent allele among all the studies was allele 27. After comparing the distributions of each allele with others, statistically significant differences have been found in the distribution of the alleles by the two groups, with an over-representation of allele (A)21 (disease: 3.22%, control: 0.44%). Thus, carrying A21 increased the risk of DDD. Such an association was not found to be statistically significant when considering the risk of OA.

Conclusions

The findings suggest that VNTR A21 seems to be associated with higher risk to DDD, however, such an association may not be statistically significant regarding the risk of OA.

Cite this article: L. Cong, G. Tu, D. Liang. A systematic review of the relationship between the distributions of aggrecan gene VNTR polymorphism and degenerative disc disease/osteoarthritis. Bone Joint Res 2018;7:308–317. DOI: 10.1302/2046-3758.74.BJR-2017-0207.R1

Developing Multipollutant Exposure Indicators of Traffic Pollution: The Dorm Room Inhalation to Vehicle Emissions (DRIVE) Study

Introduction

The Dorm Room Inhalation to Vehicle Emissions (DRIVE2) study was conducted to measure traditional single-pollutant and novel multipollutant traffic indicators along a complete emission-to-exposure pathway. The overarching goal of the study was to evaluate the suitability of these indicators for use as primary traffic exposure metrics in panel-based and small-cohort epidemiological studies.

Methods

Intensive field sampling was conducted on the campus of the Georgia Institute of Technology (GIT) between September 2014 and January 2015 at 8 monitoring sites (2 indoors and 6 outdoors) ranging from 5 m to 2.3 km from the busiest and most congested highway artery in Atlanta. In addition, 54 GIT students living in one of two dormitories either near (20 m) or far (1.4 km) from the highway were recruited to conduct personal exposure sampling and weekly biomonitoring. The pollutants measured were selected to provide information about the heterogeneous particulate and gaseous composition of primary traffic emissions, including the traditional traffic-related species (e.g., carbon monoxide [CO], nitrogen dioxide [NO2], nitric oxide [NO], fine particulate matter [PM2.5], and black carbon [BC]), and of secondary species (e.g., ozone [O3] and sulfate as well as organic carbon [OC], which is both primary and secondary) from traffic and other sources. Along with these pollutants, we also measured two multipollutant traffic indicators: integrated mobile source indicators (IMSIs) and fine particulate matter oxidative potential (FPMOP). IMSIs are derived from elemental carbon (EC), CO, and nitrogen oxide (NOx) concentrations, along with the fractions of these species emitted by gasoline and diesel vehicles, to construct integrated estimates of gasoline and diesel vehicle impacts. Our FPMOP indicator was based on an acellular assay involving the depletion of dithiothreitol (DTT), considering both water-soluble and insoluble components (referred to as FPMOPtotal-DTT). In addition, a limited assessment of 18 low-cost sensors was added to the study to supplement the four original aims.

Results

Pollutant levels measured during the study showed a low impact by this highway hotspot source on its surrounding vicinity. These findings are broadly consistent with results from other studies throughout North America showing decreased relative contributions to urban air pollution from primary traffic emissions. We view these reductions as an indication of a changing near-road environment, facilitated by the effectiveness of mobile source emission controls. Many of the primary pollutant species, including NO, CO, and BC, decreased to near background levels by 20 to 30 m from the highway source. Patterns of correlation among the sites also varied by pollutant and time of day. NO2 exhibited spatial trends that differed from those of the other single-pollutant primary traffic indicators. We believe this was caused by kinetic limitations in the photochemical chemistry, associated with primary emission reductions, required to convert the NO-dominant primary NOx, emitted from automobiles, to NO2. This finding provides some indication of limitations in the use of NO2 as a primary traffic exposure indicator in panel-based health effect studies. Roadside monitoring of NO, CO, and BC tended to be more strongly correlated with sites, both near and far from the road, during morning rush hour periods and often weakly to moderately correlated during other time periods of the day. This pattern was likely associated with diurnal changes in mixing and chemistry and their impact on spatial heterogeneity across the campus. Among our candidate multipollutant primary traffic indicators, we report several key findings related to the use of oxidative potential (OP)-based indicators. Although earlier studies have reported elevated levels of FPMOP in direct exhaust emissions, we found that atmospheric processing further enhanced FPMOPtotal-DTT, likely associated with the oxidation of primary polycyclic aromatic hydrocarbons (PAHs) to quinones and hydroxyquinones and with the oxidization and water solubility of metals. This has important implications in terms both of the utility of FPMOPtotal-DTT as a marker for exhaust emissions and of the importance of atmospheric processing of particulate matter (PM) being tied to potential health outcomes. The results from the personal exposure monitoring also point to the complexity and diversity of the spatiotemporal variability patterns among the study monitoring sites and the importance of accounting for location and spatial mobility when estimating exposures in panel-based and small-cohort studies. This was most clearly demonstrated with the personal BC measurements, where ambient roadside monitoring was shown to be a poor surrogate for exposures to BC. Alternative surrogates, including ambient and indoor BC at the participants' respective dorms, were more strongly associated with personal BC, and knowledge of the participants' mean proximity to the highway was also shown to explain a substantial level of the variability in corresponding personal exposures to both BC and NO2. In addition, untargeted metabolomic indicators measured in plasma and saliva, which represent emerging methods for measuring exposure, were used to extract approximately 20,000 and 30,000 features from plasma and saliva, respectively. Using hydrophilic interaction liquid chromatography (HILIC) in the positive ion mode, we identified 221 plasma features that differed significantly between the two dorm cohorts. The bimodal distribution of these features in the HILIC column was highly idiosyncratic; one peak consisted of features with elevated intensities for participants living in the near dorm; the other consisted of features with elevated intensities for participants in the far dorm. Both peaks were characterized by relatively short retention times, indicative of the hydrophobicity of the identified features. The results from the metabolomics analyses provide a strong basis for continuing this work toward specific chemical validation of putative biomarkers of traffic-related pollution. Finally, the study had a supplemental aim of examining the performance of 18 low-cost CO, NO, NO2, O3, and PM2.5 pollutant sensors. These were colocated alongside the other study monitors and assessed for their ability to capture temporal trends observed by the reference monitoring instrumentation. Generally, we found the performance of the low-cost gas-phase sensors to be promising after extensive calibration; the uncalibrated measurements alone, however, would likely not have led to reliable results. The low-cost PM sensors we evaluated had poor accuracy, although PM sensor technology is evolving quickly and warrants future attention.

Conclusions

An immediate implication of the changing near-road environment is that future studies aimed at characterizing hotspots related to mobile sources and their impacts on health will need to consider multiple approaches for characterizing spatial gradients and exposures. Specifically and most directly, the mobile source contributions to ambient concentrations of single-pollutant indicators of traffic exposure are not as distinguishable to the degree that they have been in the past. Collectively, the study suggests that characterizing exposures to traffic-related pollutants, which is already difficult, will become more difficult because of the reduction in traffic-related emissions. Additional multi-tiered approaches should be considered along with traditional measurements, including the use of alternative OP measures beyond those based on DTT assays, metabolomics, low-cost sensors, and air quality modeling.

[Trend of cancer mortality in Hebei province, 1973-2013]

Objective: To analyze the data of malignant tumor mortality and change in disease burden in Hebei province from 1973 to 2013. Methods: Cancer mortality rate, age-standardized mortality rate and the years of life lost due to premature mortality (YLLs) were calculated by using the data from three rounds of all death causes survey and database of cancer registry in Hebei during 1973-2013. Results: From 1973 to 2013, a linear upward of malignant tumor mortality was observed, with a 51.57% increase. The mortality rate during 1973-1975 was 98.52/100 000 and it was 149.33/100 000 during 2011-2013. During 1973-1975, the YLLs was 17.0/1 000 in males and 12.8/1 000 in females. While during 2011-2013, the YLLs was 23.2/1 000 in males and 15.9/1 000 in females. During 1973-1975, esophagus cancer, stomach cancer and liver cancer were top three leading causes of deaths. During 2011-2013, lung cancer, stomach cancer and liver cancer were main leading causes of deaths. During the past 40 years, the deaths of esophagus cancer and cervix cancer decreased dramatically, but the deaths of lung cancer and breast cancer increased sharply. Conclusions: The disease burden caused by malignant tumor is becoming more serious in Hebei. It is necessary to strengthen the primary prevention and screening of malignant tumor.

Fast quantification of fluoroquinolones in environmental water samples using molecularly imprinted polymers coupled with internal extractive electrospray ionization mass spectrometry

A simple, fast and high-sensitivity method for quantification of fluoroquinolones in environmental water samples using MIPs-iEESI-MS.

Diastereo- and enantioselective nitro-Mannich reaction of isatin-derived N-Boc ketimines catalyzed by chiral phase-transfer catalysts

A series of 3-substituted 3-amino-oxindoles were constructed in excellent yields (96–99%) with high enantioselectivities (up to 95% ee) and diastereoselectivities (up to 95 : 5 dr) catalyzed by Cinchona alkaloid-derived phase-transfer catalysts.

Investigating the mechanisms of papillary thyroid carcinoma using transcriptome analysis

As the predominant thyroid cancer, papillary thyroid cancer (PTC) accounts for 75–85% of thyroid cancer cases. This research aimed to investigate transcriptomic changes and key genes in PTC. Using RNA-sequencing technology, the transcriptional profiles of 5 thyroid tumor tissues and 5 adjacent normal tissues were obtained. The single nucleotide polymorphisms (SNPs) were identified by SAMtools software and then annotated by ANNOVAR software. After differentially expressed genes (DEGs) were selected by edgR software, they were further investigated by enrichment analysis, protein domain analysis, and protein-protein interaction (PPI) network analysis. Additionally, the potential gene fusion events were predicted using FusionMap software. A total of 70,172 SNPs and 2,686 DEGs in the tumor tissues, as well as 83,869 SNPs in the normal tissues were identified. In the PPI network, fibronectin 1 (FN1; degree=31) and transforming growth factor β receptor 1 (TGFβR1; degree=22) had higher degrees. A total of 7 PPI pairs containing the non-synonymous risk SNP loci in the interaction domains were identified. Particularly, the interaction domains involved in the interactions of FN1 and 5 other proteins (such as FN1-tenascin C, TNC) had non-synonymous risk SNP loci. Furthermore, 11 and 4 gene fusion events were identified in all of the tumor tissues and normal tissues, respectively. Additionally, the NK2 homeobox 1-surfactant associated 3 (NKX2-1-SFTA3) gene fusion was identified in both tumor and normal tissues. These results indicated that TGFβR1 and the NKX2-1-SFTA3 gene fusion may be involved in PTC. Furthermore, FN1 and TNC containing the non-synonymous risk SNP loci might serve a role in PTC by interacting with each other.

[Estimated of esophageal cancer incidence and mortality in China, 2013]

Objective: The National Central Cancer Registry (NCCR) collected esophageal data of local cancer registries in 2013 to estimate the incidence and mortality in China. Methods: Data submitted from 347 registries were evaluated and 255 registries' data are qualified by NCCR. Data of incidence and mortality were stratified with areas (urban/rural), gender and age group. Chinese population census in 2000 and Segi's population were used for age-standardized incidence/mortality. Results: All of 255 cancer registries covered a total of 226 494 490 population (111 595 772 in urban areas and 114 898 718 in rural areas). The morphology verified cases (MV%) of esophageal cancer accounted for 75.51% and 1.64% of incident cases were identified through death certifications only (DCO%) with mortality to incidence ratio of 0.75. The estimates of new esophageal cancer cases and deaths were 277 thousand and 206 thousand in China, respectively. The crude incidence rate of esophageal cancer in Chinese cancer registration areas was 20.35/10(5) (28.15/10(5) in male, 12.15/10(5) in female), age-standardized incidence rates by Chinese standard population (ASIRC) and by world standard population were 13.64/10(5) and 13.82/10(5) with the cumulative incidence rate (0-74 age years old) of 1.77%. The esophageal cancer incidence and ASIRC were 13.38/10(5) and 8.74/10(5) in urban areas whereas in rural areas, they were 28.44/10(5) and 19.56/10(5,) respectively. In rural areas, the crude incidence rate of esophageal cancer was 2.13 times higher than that in urban areas, and after age-standardized it remained 2.24 times higher. The esophageal cancer mortality in Chinese cancer registration areas was 15.17/10(5) (20.86/10(5) in male and 9.20/10(5) in female), age-standardized mortality by Chinese standard population (ASMRC) and by world standard population were 9.95/10(5) and 9.98/10(5,) with the cumulative mortality rate (0-74 age years old) of 1.20%. The esophageal cancer mortality and ASMRC were 10.12/10(5) and 6.46/10(5) in urban areas, whereas in rural areas, they were 21.05/10(5) and 14.16/10(5,) respectively. In rural areas, the esophageal cancer mortality and ASMRC were 2.08 and 2.19 times higher than those in urban areas. Esophageal cancer was the sixth common cancer and the fourth leading causes of cancer death, accounting for about 7.52% of all cancer cases and 9.26% of all cancer deaths. Conclusions: Esophageal cancer is one of the most common cancers in China. Screening and early detection are important to reduce the incidence and mortality.

Study on the effect of Integrin αVβ6 on proliferation and apoptosis of cervical cancer cells

OBJECTIVE

To analyze the influence of Integrin αVβ6 on proliferation and apoptosis of cervical cancer cells.

PATIENTS AND METHODS

Fifty-two patients with benign cervical lesions, 55 cervical cancer patients, and 20 healthy controls were selected as research subjects. The positive expression rate of Integrin αVβ6 was detected in cervical tissue samples by immunohistochemistry. The relative expressions of the proliferation-related proteins, p53, PCNA, Ki-67, and TIPE2, and the apoptosis-related proteins, Cyto-C, AIF, caspase-3, Bag-1, Bcl-2, and p-Akt were measured by Western blot.

RESULTS

The positive rate of Integrin αVβ6 expression was higher in tissue from cervical cancer patients than in the other two groups (p < 0.05). The levels of expression of p53, PCNA, and Ki-67 in the cervical cancer group were higher, while the levels of TIPE2 were lower compared with the other two groups (p < 0.05). The levels of expression of Bag-1 and Bcl-2 were higher in the cervical cancer group, but Cyto-C, AIF, caspase-3, and p-Akt were lower compared with the other two groups (p < 0.05). Compared with cervical cancer patients with negative Integrin αVβ6 expression, patients with positive Integrin αVβ6 expression had different expression levels of the proliferation- and apoptosis-related proteins, and the differences were statistically significant (p < 0.05).

CONCLUSIONS

High expression of Integrin αVβ6 is an important cause of active proliferation and impaired apoptosis in cervical cancer. Integrin αVβ6 is a promising target for the treatment of cervical cancer.

RUVBL1-ITFG1 interaction is required for collective invasion in breast cancer

BACKGROUND

The mechanisms of breast cancer collective invasion are poorly understood limiting the metastasis therapy. The ATPase RUVBL1 is frequently overexpressed in various cancers and plays a crucial role in oncogenic process. We further investigated the role of RUVBL1 in promoting collective invasion and uncovered that targeting RUVBL1 could inhibit metastatic progression.

METHODS

The expression levels of RUVBL1 and ITFG1 were examined by Western blot and qRT-PCR. Co-localization and interaction of RUVBL1 and ITFG1 were determined by immunofluorescence and co-immunoprecipitation. The invasive ability was examined by transwell assay and microfluidic assay. The metastatic and tumorigenic abilities of breast cancer cells were revealed in BALB/c nude mice by xenograft and tail vein injection.

RESULTS

ATPase RUVBL1 is highly expressed in breast cancer and predicts the poor prognosis. Elevated expression of RUVBL1 is found in high metastatic breast cancer cells. Silencing RUVBL1 suppresses cancer cell expansion and invasion in vitro and in vivo. RUVBL1 interacts with a conserved transmembrane protein ITFG1 in cytoplasm and plasma membrane to promote the collective invasion. Using a microfluidic model, we demonstrated that silencing RUVBL1 or ITFG1 individually compromises collective invasion of breast cancer cells.

CONCLUSION

RUVBL1 is a vital regulator for collective invasion. The interaction between RUVBL1 and ITFG1 is required for breast cancer cell collective invasion and progression.

GENERAL SIGNIFICANCE

Targeting collective invasion promoted by RUVBL1-ITFG1 complex provides a novel therapeutic strategy to improve the prognosis of invasive breast cancer.

[Study on the contribution rate of follow-up formula to the nutrient intake of infants and young children aged 7-24 months in China]

Objective: To determine the contribution of follow-up formula (FUF) to the nutrient intake of 7-24-month-old infants and young children. Methods: The cluster random sampling method and the convenience sampling method were used in combination, and geographic and economic factors were taken into consideration. Four areas of China (Beijing, Hebei, Guangxi, Guangdong) were selected, with 120 infants chosen from each of these areas (half of which were 7-12 months old, and half were 13-24 months old). A dietary survey was completed by a continuous 24-hour weighing method over two days. Questionnaires were completed by their caregivers which included weighing the FUF and supplementary food given to the infant, and recording the frequency of breast feeding and any supplementary nutrients. A total of 518 questionnaires were distributed, and 472 questionnaires qualified for inclusion. Nutrient intake was calculated using the China food composition, infant formula food nutrient content and infant nutrition supplement brand-label information databases, and then the nutrient intake proportion (the percentage of estimated energy requirement (EER%), recommended nutrient intake (RNI%) or adequate intake (AI%)), and the contribution rate of FUF were analyzed. Results: A total of 472 infants were investigated (227 infants aged 7-12 months old, 245 infants aged 13-24 months old). The findings revealed that the median energy intake of 7- 12-month-old and 13- 24-month-old infants were 2 530.08 kJ and 3 445.48 kJ, respectively, which accounted for 85.18% and 94.14% of EER, respectively; and the median intake of protein reached 91.50% and 105.88% of their RNI/AI, respectively. For micronutrients, the median intake of vitamin B₁, vitamin B₂, niacin, vitamin E, potassium, zinc and manganese in 7- 12-month-old infants and vitamin B₂, vitamin E, potassium, magnesium, iron and manganese in 13-24-month-old children accounted for 82.00% and 114.29% of RNI/AI (RNI%/AI%), respectively. The intake of vitamin B₆, iron and selenium in 7-12-month-old infants and vitamin B₁, vitamin B₆, vitamin C, calcium and selenium in 13-24-month-old children was less than 80% RNI/AI. Furthermore, some nutrients showed higher intake levels, such as vitamin A, calcium, phosphorus and magnesium in 7-12-month-old infants and vitamin A and phosphorus in 13-24-month-old children, which were higher than 130% RNI/AI. In total, 40.53% (92) of infants aged 7-12 months and 52.65% (129) of children aged 13- 24 months were fed FUF as part of their diet, and its contribution rate to macronutrients was 29.69% for carbohydrates and 51.77% for fats, and to micronutrients was 2.04% for manganese and 74.24% for vitamin C. Conclusion: FUF contributes to the nutrient intake of infants and young children aged from 7-24 months old at different rates depending on the macronutrient or micronutrient analyzed.

Novel α-amino acid-derived phase-transfer catalyst application to a highly enantio- and diastereoselective nitro-Mannich reaction

Very broad substrate generality was observed, and the products were achieved in high enantio-/diastereoselectivities (90–>99.9% ee, 9 : 1 to 11 : 1 dr).

A novel dual-emission QDs/PCDs assembled composite nanoparticle for high sensitive visual detection of Hg2+

Traditional fluorescent probe detection is an established technique for enhancing or quenching luminescence intensity; however, a color changeable fluorescent material is still a challenge in many target detection fields.

VEGF Promotes Glycolysis in Pancreatic Cancer via HIF1α Up-Regulation

BACKGROUND

Vascular endothelial growth factor (VEGF) is highly expressed in many types of tumors, including pancreatic cancer. Tumor cellderived VEGF promotes angiogenesis and tumor progression. However, the role of VEGF in glucose metabolism remains unclear.

OBJECTIVE

We investigated the role and the underlying mechanism of VEGF in the glucose metabolism of pancreatic cancer cells.

METHOD

Pancreatic cancer cells were stimulated with VEGF165 for 1 or 2 h. The oxygen consumption rates (OCR) and extracellular acidification rates (ECAR) were measured using the Seahorse XF96 Extracellular Flux Analyzer. Glycolytic enzymes were detected by quantitative real-time PCR. Neuropilin 1 (NRP1) was silenced by shRNA in order to investigate its role in VEGF-induced glycolysis. Immunohistochemistry (IHC) was performed to identify the correlation among VEGF, NRP1 and hypoxia inducible factor 1α (HIF1α) in pancreatic cancer tissues.

RESULTS

VEGF stimulation led to a metabolic transition from mitochondrial oxidative phosphorylation to glycolysis in pancreatic cancer. HIF1α and NRP1 protein levels were both increased after VEGF stimulation. The down-regulation of NRP1 reduced glycolysis in pancreatic cancer cells. NRP1 and VEGF levels both correlated with HIF1α expression in pancreatic tumor tissues.

CONCLUSION

VEGF enhances glycolysis in pancreatic cancer via HIF1α up-regulation. NRP1 plays a key role in VEGF-induced glycolysis.