[Identification of key genes in Wilms tumor based on high-throughput RNA sequencing and their impacts on prognosis and immune responses]

OBJECTIVE

To identify the key genes differentially expressed in Wilms tumor and analyze their potential impacts on prognosis and immune responses of the patients.

METHODS

High-throughput RNA sequencing was used to identify the differentially expressed mRNAs in clinical samples of Wilms tumor and paired normal tissues, and their biological functions were analyzed using GO, KEGG and GSEA enrichment analyses. The hub genes were identified using STRING database, based on which a prognostic model was constructed using LASSO regression. The mutations of the key hub genes were analyzed and their impacts on immunotherapy efficacy was predicted using the cBioPortal platform. RT-qPCR was used to verify the differential expressions of the key hub genes in Wilms tumor.

RESULTS

Of the 1612 differentially expressed genes identified in Wilms tumor, 1030 were up-regulated and 582 were down-regulated, involving mainly cell cycle processes and immune responses. Ten hub genes were identified, among which 4 genes (TP53, MED1, CCNB1 and EGF) were closely related to the survival of children with Wilms tumor. A 3-gene prognostic signature was constructed through LASSO regression analysis, and the patients stratified into with high- and low-risk groups based on this signature had significantly different survival outcomes (HR=1.814, log-rank P=0.002). The AUCs of the 3-, 5- and 7-year survival ROC curves of this model were all greater than 0.7. The overall mutations in the key hub genes or the individual mutations in TP53/CCNB1 were strongly correlated with a lower survival rates, and a high TP53 expression was correlated with a poor immunotherapy efficacy. RT-qPCR confirmed that the key hub genes had significant differential expressions in Wilms tumor tissues and cells.

CONCLUSION

TP53 gene plays an important role in the Wilms tumor and may potentially serve as a new immunotherapeutic biomarker as well as a therapeutic target.

Sophora tonkinensis: response and adaptation of physiological characteristics, functional traits, and secondary metabolites to drought stress

The medicinal plant Sophora tonkinensis is a characteristic Chinese shrub of karst areas. The arid climate in karst areas produces high-quality S. tonkinensis; however, the mechanisms of drought tolerance are not clear, which restricts sustainable plantings of S. tonkinensis. This study involved a 20-day drought stress experiment with potted S. tonkinensis and threee soil water regimes: control (CK), mild drought (MDT), and severe drought (SDT). Plant morphology, biomass, physiological indicators, alkaloid content, and other changes under drought stress were monitored. The content of soluble sugars and proteins, and activity of antioxidant enzymes in leaves and roots were higher under drought than CK, indicating that S. tonkinensis is tolerant to osmotic stress in early drought stages. Content of matrine and oxymatrine increased gradually with increasing drought duration in the short term. The epidermis of S. tonkinensis leaves have characteristics of desert plants, including upper epidermal waxy layer, lower epidermal villi, and relatively sunken stomata, suggesting that S. tonkinensis has strong drought tolerance. In conclusion, drought stress changed the cell structure of S. tonkinensis, induced antioxidant enzyme activity and increased its resistance to drought.

Ca substitution improves the catalytic activity of perovskite LaCoO3 toward toluene: comprehension of electronic structure alteration

For perovskite La1-xCaxCoO3 (Ca-x, x = 0-0.3), Ca-0.2 with the closest O p band center to the Fermi level, displays the best catalytic activity for toluene oxidation. The O p band center determines the reducibility and active oxygen content. This finding is beneficial for the design of highly active perovskite catalysts.

Fast and slow skeletal myosin binding protein-C and aging

Aging is associated with skeletal muscle strength decline and cardiac diastolic dysfunction. The structural arrangements of the sarcomeric proteins, such as myosin binding protein-C (MyBP-C) are shown to be pivotal in the pathogenesis of diastolic dysfunction. Yet, the role of fast (fMyBP-C) and slow (sMyBP-C) skeletal muscle MyBP-C remains to be elucidated. Herein, we aimed to characterize MyBP-C and its paralogs in the fast tibialis anterior (TA) muscle from adult and old mice. Immunoreactivity preparations showed that the relative abundance of the fMyBP-C paralog was greater in the TA of both adult and old, but no differences were noted between groups. We further found that the expression level of cardiac myosin binding protein-C (cMyBP-C), an important modulator of cardiac output, was lowered by age. Standard SDS-PAGE along with Pro-Q Diamond phosphoprotein staining did not identify age-related changes in phosphorylated MyBP-C proteins from TA and cardiac muscles; however, it revealed that MyBP-C paralogs in fast skeletal and cardiac muscle were highly phosphorylated. Mass spectrometry further identified glycogen phosphorylase, desmin, actin, troponin T, and myosin regulatory light chain 2 as phosphorylated myofilament proteins in both ages. MyBP-C protein-bound carbonyls were determined using anti-DNP immunostaining and found the carbonyl level of fMyBP-C, sMyBP-C, and cMyBP-C to be similar between old and adult animals. In summary, our data showed some differences regarding the MyBP-C paralog expression and identified an age-related reduction of cMyBP-C expression. Future studies are needed to elucidate which are the age-driven post-translational modifications in the MyBP-C paralogs.

UV/chlorine and chlorination of effluent organic matter fractions: Tracing nitrogenous DBPs using FT-ICR mass spectrometry

UV/chlorine process is a promising advanced treatment to eliminate pathogen and remove refractory micropollutants for reclamation of municipal secondary effluent. However, effluent organic matter (EfOM) featuring high organic nitrogen content serves as a potential precursor for nitrogenous disinfection byproducts (N-DBPs) of health concern. The molecular-level alteration of a hydrophobic (HPO) EfOM fraction and a transphilic (TPI) EfOM fraction isolated from the same municipal effluent and the formation of N-DBPs in the UV/chlorine were tracked by ultrahigh-resolution mass spectrometry. Compared with chlorination, UV/chlorine induced a significantly greater modification on the molecular composition of EfOM and resulted in formation of unique formulae and chlorinated molecules with higher degree of oxidation, lower aromaticity, and less carbon number due to the involvement of reactive radical species. For both EfOM fractions, UV/chlorine formed more diverse DBPs with higher intensity and Cl-incorporation than chlorination. The TPI fraction of EfOM characterized by higher O/C and N/C ratios generated more N-DBPs with higher intensity clustered in the high O/C region than the HPO fraction of EfOM by both UV/chlorine and chlorination. Totally, 207 and 117 nitrogen-containing chlorinated formulae were recorded after UV/chlorine treatment of TPI and HPO, respectively. Precursor tracking found a greater number of DBPs were originated from raw EfOM through electrophilic substitution pathway rather than chlorine addition. Toxicity bioassays demonstrated that DBPs can trigger oxidative stress-induced DNA damage, while HPO fraction of EfOM dominated the induction of cytotoxicity. However, no correlation could be established between the diversity/abundance of N-DBPs and the level of DNA damage. A total of 22 DBPs with a significant rank correlation with DNA damage were identified, while C₈H₆O₅NCl was found as the N-DBP with the strongest correlation. The potential toxic chlorine-containing formula with the most abundant intensity was assigned to C₅HO₃Cl₃. This study suggests that the character and transformation of EfOM and associated toxicity is critical to evaluate the UV/chlorine process toward practical application.

Controlling oxygen vacancies of CoMn2O4 by loading on planar and tubular clay minerals and its application for boosted PMS activation

A representative transition metal oxide (TMO), CoMn₂O₄ (CMO), is recognized as an effective peroxymonosulfate (PMS) activator with disadvantages like limited reactive sites and metal leakage. Herein, novel catalysts were synthesized by anchoring CMO on kaolinite (Kln) and halloysite (Hal) matrixes, two natural clay minerals with lamellar and tubular structures, for PMS activation in pharmaceutical degradation. Hal and Kln helped to control the crystallinity of CMO spontaneously with induce oxygen vacancies (OVs), which significantly enhanced the working efficiency. The reaction rate constants of Hal/CMO and Kln/CMO towards OFX degradation were nearly triple and twice that of bare CMO, respectively, with a 60% decrease in metal usage. The formation of OVs provided additional active sites for the reaction and accelerated the electron transfer. CMO/Hal and CMO/Kln exhibited better stability and durability than CMO, while CMO/Kln showed higher structural stability with lower metal leaching after 3 rounds of reaction. The higher crystallinity of CMO/Kln resulted in less OVs, but higher structural stability. The universal applicability of CMO/Hal and CMO/Kln were verified by using three other pharmaceuticals as probes. This work shed light on the modification of TMO catalysts by introducing clay mineral substrates for the efficient and ecofriendly remediation of pharmaceuticals in wastewater.

Effect of electron structure on the catalytic activity of LaCoO3 perovskite towards toluene oxidation

LaCoO₃ perovskites with different spin states of Co³⁺ were prepared by calcination at 600-1000 °C. LaCoO₃ with electron filling in the e_g orbital at 1 exhibited a moderate interaction between the surface oxygen, resulting in the best catalytic activity. This was verified by the O p-band center.

Occurrence and risk assessment of currently used organophosphate pesticides in overlying water and surface sediments in Guangzhou urban waterways, China

Organophosphate pesticides (OPPs) are one type of the most massively used pesticides and ubiquitously detected in aquatic environments, which may pose potential risks to the aquatic organisms and human health. In the present study, the spatiotemporal distribution and potential risks of OPPs were investigated in overlying water and surficial sediments from urban waterways of Guangzhou. For all studied sites, in general, four target OPPs (i.e., malathion, chlorpyrifos, terbufos, and diazinon) were present in the overlying water, with malathion and chlorpyrifos as major components. Higher concentrations of the four OPPs were found for the water and sediments collected in the dry season compared to the wet season, possibly because of the dilution effect of heavy rains. The results of Pearson's analyses and principal coordinate analyses (PCoA) suggested similar sources for target OPPs in the water and sediments across the Guangzhou urban waterways. Potential ecological risks of the OPPs to three representative taxons (algae, aquatic invertebrates, and fish) were evaluated via toxic units (TUs) and risk quotients (RQs), while risk assessment on human health was performed using hazard index (HI). Although TU results showed no acute risks to the aquatic organisms in the overlying water and surface sediments, RQ results of the mixture showed high risks to the aquatic invertebrate and fish in all water samples. Individual HI values and cumulative HI values were on the order of 10^-6-10^-3 for children and adults, suggesting no potential risks to either children or adults through drinking and bathing.

[ELF4 promotes proliferation and inhibits apoptosis of human insulinoma cells by activating Akt signaling]

OBJECTIVE

To investigate the effect of overexpression of the oncogenic transcription factor ELF4 on proliferation and apoptosis in human insulinoma cells and explore the underlying mechanism.

METHODS

A human insulinoma BON cell line with stable overexpression of ELF4 (BON-ELF4 cells) was constructed using a recombinant retrovirus vector and the expression of ELF4 protein was verified using Western blotting. MTT assay was used to assess the proliferation of BON-ELF4 cells and BON-Vector cells, and the cell apoptosis induced by treatment with epirubicin (0.1 μmol/L for 24 h) was analyzed by detecting the expressions of cleaved caspase-8, caspase-9, and PARP using Western blotting. Flow cytometry with Annexin VFITC/PI staining was performed to analyze the numbers of apoptotic BON-Vector or BON-ELF4 cells. The expressions of phosphorylated Akt and total Akt in the cells were detected using Western blotting.

RESULTS

BON-ELF4 cell line with stable overexpression of ELF4 was successfully established. ELF4 overexpression significantly promoted the proliferation (P < 0.05) and obviously suppressed epirubicin- induced apoptosis in BON cells, resulting also in significantly reduced expressions of cleaved caspase-8, caspase-9 and PARP (P < 0.05). The results of flow cytometry showed a significantly lower apoptotic rate in BON-ELF4 cells than in BON-Vector cells following epirubicin treatment (6.03% vs 22.90%). The phosphorylation levels of Akt (Thr308 and Ser473) were significantly increased (P < 0.05) while the level of total Akt remained unchanged (P>0.05) in ELF4- overexpressing cells.

CONCLUSION

ELF4 overexpression enhances the proliferation and suppresses apoptosis of insulinomas cells by activating Akt signaling.

Sodium butyrate relieves lung ischemia-reperfusion injury by inhibiting NF-κB and JAK2/STAT3 signaling pathways

OBJECTIVE

Ischemia-reperfusion (IR) is the main cause of acute lung injury (ALI) in clinical lung transplantation, extracorporeal circulation, lung sleeve resection, trauma and cardiopulmonary resuscitation. The inflammatory response and oxidative stress following IR are factors that cause and aggravate its secondary damage. The purpose of this study was to investigate the efficacy and mechanism of sodium butyrate (NaB) on lung ischemia-reperfusion injury (LIRI).

MATERIALS AND METHODS

We used male C57BL/6 mice to construct the LIRI model and administered the mice with NaB. By examining the expression of inflammatory factors and oxidative stress-related molecules in mouse lung tissue, we investigated the effects of NaB on inflammation and oxidative stress in lung tissue after IR. In addition, the changes in the activity of the NF-κB and JAK2/STAT3 signaling pathways were also examined to determine the mechanism of NaB.

RESULTS

The expression levels of the inflammatory factors (IL-1β, IL-6 and TNF-α) in lung tissue of mice after IR were significantly increased, while NaB reduced the expression of inflammatory factors. In addition, the oxidative stress level of mouse lung tissue after IR increased significantly, showing the decrease of antioxidant molecules SOD1/2, catalase (CAT), and Peroxiredoxin 1 (Prdx1), while the intake of NaB increased the antioxidant level of mouse lung tissue. The activities of NF-κB and JAK2/STAT3 signaling pathways were significantly increased in lung tissue after IR, whereas NaB inhibited the activity of NF-κB and JAK2/STAT3 signaling pathways.

CONCLUSIONS

NaB relieves LIRI by inhibiting NF-κB and JAK2/STAT3 signaling pathways to reduce inflammation and oxidative stress levels in lung tissue of mice after IR.

Does active surveillance avoid overtreatment in prostate cancer? Lessons learned from salvage radical prostatectomies

OBJECTIVE

Determine whether our institution´s active surveillance (AS) protocol is a suitable strategy to minimise prostate cancer overtreatment.

MATERIAL AND METHODS

Retrospective analysis of 516 patients on AS after prostate cancer diagnosis. Population divided into "per-protocol" vs "induced" AS depending on fulfilment of protocol´s inclusion criteria. Radical prostatectomies after AS were selected and stratified based on: reclassification, progression or patient anxiety. Clinicopathological features and biochemical relapse-free survival were studied. Primary endpoint was overtreatment ratio based on the presence of insignificant prostate cancer and adverse pathological features in the surgical specimen. Kaplan-Meier curves were used to estimate the biochemical relapse-free survival and compared with log-rank test.

RESULTS

304 patients fulfilled inclusion criteria; 100 proceeded to radical prostatectomy (31% "induced", 69% "per-protocol" AS). Surgery indications were reclassification, progression and anxiety in 66%, 18% and 16% of patients respectively. Rate of positive lymph nodes was higher in the progression group (11%) compared to reclassification and anxiety (5% and 0% respectively, P = .002). Positive surgical margins were more frequently reported in the progression cohort compared to reclassification (28% vs 20%). Median follow-up from diagnosis until last radical prostatectomy was 48.3 months (32.4-70). 3 year biochemical relapse-free survival in the salvage radical prostatectomy was 85.4% (95 CI 78.3-93.2). Insignificant cancer was noticed in 7% of patients (Epstein´s vs 24% Wolters´ criteria). Rate of patients with adverse pathological features was 36%.

CONCLUSIONS

The majority of patients who underwent salvage surgery after AS were not overtreated. Radical prostatectomy should be considered a safe rescue treatment.

Multiple hospitalisations towards the end of life among patients with serious mental illness: A retrospective cohort study in England, UK

Introduction

Multiple hospitalisations towards the end of life is an indicator of poor-quality care. Understanding the characteristics of patients who experience hospitalisations at the end-of-life and how they vary is important for improved care planning.

Objectives

To describe socio-demographic and clinical characteristics of patients diagnosed with serious mental illness who experienced multiple hospitalisations in the last 90 days of life.

Methods

Data for all adult patients with a diagnosis of serious mental illness who died in 2018-2019 in England, UK were extracted from the National Mental Health Services Data Set linked with Hospital Episode Statistics and death registry data. Variables of interest included age, gender, marital status, underlying and contributory cause of death, ethnicity, place of death, deprivation status, urban-rural indicator, and patient’s region of residence. The number of hospitalisations and patient’s sociodemographic & clinical were described using descriptive statistics and percentages, respectively.

Results

Of the 45924 patients, 38.1% (n=17505, Male=42.9%, Female=57.1%, Mean age:78.4) had at least one hospitalisation in the last 90 days of life. The median number of hospitalisations was 2(StdDev:1.64, Minimum=1,Maximum=23). Most of those hospitalised (n=11808, 67.5%), died in a health care establishment (e.g. Hospital or hospice). There were marked geographic differences in the proportions of hospitalisations.The North West region of England recorded the most hospitalisations (n= 2906,16.6%), compared to other regions.

Conclusions

Further analysis is needed to understand factors independently associated with hospitalisations in people with serious mental illness. Funding: This project is supported by the National Institute for Health Research (NIHR) Applied Research Collaborations (ARC) South London.

Clash of the calculators: External validation of prostate cancer risk calculators in men undergoing mpMRI and transperineal biopsy

Objective

To compare the accuracy of the European Randomized Study of Screening for Prostate Cancer (ERSPC) RC, MRI‐ERSPC‐RC, and Prostate Biopsy Collaborative Group (PBCG) RC in patients undergoing transperineal prostate biopsy.

Patients and methods

We identified 392 patients who underwent mpMRI before transperineal prostate biopsy across multiple public and private institutions between January 2017 and August 2019. The estimated probabilities of detecting PCa and significant PCa were calculated using the MRI‐ERSPC‐RC, ERSPC‐RC, and PBCG‐RC. Receiver operating characteristic (ROC) curves for each calculator were generated and the area underneath the curve (AUC) was compared. Calibration and clinical utility were assessed with calibration plots and decision curve analysis, respectively.

Results

PCa was detected in 285 patients (72.7%) with significant PCa found in 200 patients (51.1%). ROC curve analysis found the MRI‐ERSPC‐RC outperformed the ERSPC‐RC and PBCG‐RC. For the prediction of PCa, the AUC was 0.756, 0.696, and 0.675 for the MRI‐ERSPC‐RC, ERSPC‐RC, and PBCG‐RC, respectively. The AUC for the prediction of significant PCa was 0.803, 0.745, and 0.746 for the MRI‐ERSPC‐RC, ERSPC‐RC, and PBCG‐RC, respectively.

Conclusions

Our study validated the ERSPC‐RC, MRI‐ERSPC‐RC, and PBCG‐RC in a cohort undergoing transperineal prostate biopsy with the MRI‐ERSPC‐RC performing the best. These RCs may enable improved shared decision making and help to guide patient selection for biopsy.

[Effect of piRNA NU13 in regulating biological behaviors of human Wilms tumor cells in vitro]

OBJECTIVE

To investigate the role of the differential piRNA NU13 derived from piwil2-induced cancer stem-like cells (piwil2-iCSCs) in regulating biological behaviors of Wilms tumor cells (G401).

OBJECTIVE

The expressions of piRNA NU13 and NOP56 were detected in Wilms tumor cell line G401 using RT-qPCR. G401 cells were transfected with piRNA NU13 mimics and inhibitor for its over-expression and inhibition, and the transfection efficiency was verified with RT-qPCR. The changes in proliferation of G401 cells after transfection were detected using CCK8 assay, and cell apoptosis was analyzed using flow cytometry. Wound healing assay and Transwell assay were performed to examine the changes in migration and invasion abilities of the transfected cells. The binding of NOP56 and piRNA NU13 was detected using dual luciferase experiment. The protein expressions of MMP2, MMP9, BAX, Bcl2, and NOP56 in the cells were detected with Western blotting.

OBJECTIVE

RTqPCR showed that the expression of piRNA NU13 decreased significantly in human Wilms tumor G401 cells as compared with that in renal tubular epithelial cell line HK2 (P < 0.05), and NOP56 was highly expressed in G401 cells and Wilms tumor tissues (P < 0.05). Over-expression of piRNA NU13 significantly suppressed the proliferation, migration and invasion of G401 cells, promoted cell apoptosis (P < 0.05), inhibited the expression of MMP2, MMP9 and Bcl2, and enhanced the expression of BAX (P < 0.05). The results of dual luciferase experiment showed that piRNA NU13 did not bind to NOP56 directly but regulated the expression of NOP56 in an indirect manner.

OBJECTIVE

piRNA NU13 is down-regulated and NOP56 is highly expressed in Wilms tumor. piNU13 may regulate the expression of NOP56 indirectly to inhibit the proliferation, migration and invasion and promote apoptosis of Wilms tumor cells in vitro.

Does active surveillance avoid overtreatment in prostate cancer? Lessons learned from salvage radical prostatectomies

OBJECTIVE

Determine whether our institution's active surveillance (AS) protocol is a suitable strategy to minimise prostate cancer overtreatment.

MATERIAL AND METHODS

Retrospective analysis of 516 patients on AS after prostate cancer diagnosis. Population divided into «per-protocol» vs «induced» AS depending on fulfilment of protocol's inclusion criteria. Radical prostatectomies after AS were selected and stratified based on reclassification, progression or patient anxiety. Clinicopathological features and biochemical relapse-free survival were studied. Primary endpoint was overtreatment ratio based on the presence of insignificant prostate cancer and adverse pathological features in the surgical specimen. Kaplan-Meier curves were used to estimate the biochemical relapse-free survival and compared with log-rank test.

RESULTS

304 patients fulfilled inclusion criteria; 100 proceeded to radical prostatectomy (31% «induced», 69% «per-protocol» AS). Surgery indications were reclassification, progression and anxiety in 66%, 18% and 16% of patients, respectively. Rate of positive lymph nodes was higher in the progression group (11%) compared to reclassification and anxiety (5% and 0%, respectively; P=.002). Positive surgical margins were more frequently reported in the progression cohort compared to reclassification (28% vs 20%). Median follow-up from diagnosis until last radical prostatectomy was 48.3months (32.4-70). Three year biochemical relapse-free survival in the salvage radical prostatectomy was 85.4% (95%CI: 78.3-93.2). Insignificant cancer was noticed in 7% of patients (Epstein's vs 24% Wolters' criteria). Rate of patients with adverse pathological features was 36%.

CONCLUSIONS

The majority of patients who underwent salvage surgery after AS were not overtreated. Radical prostatectomy should be considered a safe rescue treatment.

Changes of substrate microbial biomass and community composition in a constructed mangrove wetland for municipal wastewater treatment during 10-years operation

Constructed wetlands (CWs) have been used for wastewater treatment for decades, but research on microorganisms involved, especially long-term changes, is still limited. In this study, we evaluated changes in the substrate microbial community in a pilot-scale horizontal subsurface-flow constructed mangrove wetland during 10-years operation. In the 3rd year of operation, microbial biomass carbon and phospholipid fatty acids (PLFAs) reached peak values in two vegetated belts planted with Aegiceras corniculatum (Ac) and Kandelia obovata (Ko), respectively, then stabilized or declined in the 9th and 10th years of operation. PLFA profiles reflecting microbial community compositions varied significantly in the Ac belt during the operation period. Principal component (PCA) and redundancy analyses (RDA) revealed that microbial community compositions were significantly correlated with organic matter content, especially in the 9th and 10th years of operation, implying that the substrate microbial community in constructed mangrove wetland is sensitive to substrate characteristics and can be used as an indicator for long-term performance of CWs.

Facile surface improvement of LaCoO3 perovskite with high activity and water resistance towards toluene oxidation: Ca substitution and citric acid etching

We employ two facile modification methods, i.e., Ca substitution and citric acid etching, to further improve the catalytic activity of LaCoO₃ perovskite towards toluene oxidation.

Enhanced β-glucan and pullulan production by Aureobasidium pullulans with zinc sulfate supplementation

The effects of mineral salts on the production of exopolysaccharides, including β-glucan and pullulan, by Aureobasidium pullulans CCTCC M 2012259 were investigated. Zinc sulfate at certain concentrations decreased dry biomass but favored to the biosynthesis of both exopolysaccharides. When 100 mg/L zinc sulfate was added to the fermentation medium, production of β-glucan and pullulan increased by 141.7 and 10.2%, respectively, when compared with that noted in the control without zinc sulfate addition. To reveal the physiological mechanism underlying improved β-glucan and pullulan production, key enzymes activities, energy metabolism substances, intracellular uridine diphosphate glucose (UDPG) levels, and gene expression were determined. The results indicated that zinc sulfate up-regulated the transcriptional levels of pgm1, ugp, fks, and kre6 genes, increased activities of key enzymes involved in the biosynthesis of UDPG, β-glucan and pullulan, enhanced intracellular UDPG content, and improved energy supply, all of which contributed to the increment in β-glucan and pullulan production. The present study not only provides a feasible approach to improve the production of exopolysaccharides but also contributes to better understanding of the physiological characteristics of A. pullulans.

Remarkable effect of Co substitution in magnetite on the reduction removal of Cr(VI) coupled with aqueous Fe(II): Improvement mechanism and Cr fate

The interaction between magnetite and aqueous Fe(II) profoundly impacts the mineral recrystallization, trace-metal sequestration, and contaminant reduction. The iron ions in natural magnetite are extensively substituted by other cations. It is still unclear whether the substitution with thermodynamically favorable redox repairs (e.g., Co²⁺/Co³⁺) plays a vital role in the reducing capability of the coupled system. Herein, a series of Co-substituted magnetite samples (Fe_3-xCo_xO₄, 0.00 ≤ x ≤ 1.00) were synthesized and tested for the reductive removal of Cr(VI) in the presence of Fe(II). Fe_3-xCo_xO₄ had a spinel structure with the preferential occupancy of Co²⁺ on octahedral sites. No visible variation in the BET surface area was observed, whereas the surface site density increased gradually with Co substitution. Cr(VI) was found first adsorbed on the Fe_3-xCo_xO₄ surface and then reduced to Cr(III) by the structural Fe²⁺ and the absorbed Fe(II), accompanied by the oxidation of bulk Fe²⁺ and surface Fe(II) in Fe_3-xCo_xO₄ without phase transformation. The Cr(III) was precipitated on the Fe_3-xCo_xO₄ surface with Fe(III), or substituted octahedral Fe in Fe_3-xCo_xO₄. Both the reaction kinetics and the electron transfer efficiency revealed that Co substitution significantly improved the reactivity of Fe_3-xCo_xO₄/Fe(II) towards Cr(VI) reduction. This was ascribed to the presence of the redox pairs Co²⁺/Co³⁺ and Fe²⁺/Fe³⁺ accelerating electron transfer from the Fe_3-xCo_xO₄ interface to Cr(VI).

Abstract P5-18-02: A quantitative centrosomal amplification score (CAS) predicts local recurrence in ductal carcinoma in situ

Background: About 60-80% of ductal carcinoma in situ (DCIS) cases are high-grade (HG) DCIS with an elevated risk of local recurrence (LR) even after a lumpectomy. Patients are often under or over treated due to the lack of accurate recurrence risk prediction models. Current prognostic models such as OncotypeDX and Van Nuys Prognostic Index (VNPI) lack consistency and are limited to a specific subset of patients. Here in this study, we show that the extent of centrosome amplification (CA) in a DCIS lesion can predict the risk of LR after lumpectomy. CA refers to presence of supernumerary or large centrosomes and is a characteristic of pre-invasive lesions, and breast tumors, and promotes erroneous mitoses and chromosomal instability.

Methods: We have pioneered a semi-automated pipeline that integrates immunofluorescence confocal microscopy with digital image analysis and yields a quantitative Centrosomal Amplification Score (CAS) for each patients' tumor sample by evaluating severity and frequency of centrosomal aberrations therein. To this end, we first immunofluorescently stained centrosomes in formalin fixed paraffin embedded resection samples from DCIS patients (discovery cohort n=133 and a validation cohort n=119) using an antibody against γ-tubulin, and co-stained nuclei with DAPI. Next, we imaged the slides and processed the raw 3D image data using IMARIS Biplane 8.2 3D volume rendering software. Finally, we calculated centrosome numbers and volume in ˜250 cells from each patient sample. Using a mathematical algorithm, we generated a composite CAS score for each patient sample by integrating the numerical (CASi) and structural (CASm) aberrations.

Results: We found that DCIS patients with recurrence exhibited higher CAS. Intriguingly, higher CAS was also associated with greater risk of developing ipsilateral breast events [Hazard ratio (HR) =7.58 for discovery cohort and HR=5.8 for validation cohort, p&lt;0.0001] which remained significant (HR=8.5 for discovery and HR=3.39, p&lt;0.0001) after accounting for the confounding factors like age, tumor size, comedo necrosis and radiotherapy. Kaplan Meir survival analysis indicated that high CAS was associated with poor recurrence-free survival (RFS) (p&lt;0.001). For the high and low CAS groups, the 5-year risk of recurrence was 87.5% and 12.5% respectively (p&lt;0.001). In our discovery cohort, a head-to-head comparison of the ability of VNPI and CAS to predict recurrence illuminated that CAS was able to stratify the DCIS group in recurrence and recurrence-free group with much higher significance (p&lt;0.0001) than the Van Nuys Prognostic Index (VNPI) (HRs for CAS- 8.8 vs. VNPI 0.959). Finally, the Harrell's concordance index using SAS PROC PHREG tests yielded that the probability of a patient with poorer/lower RFS to be in the high CAS group is 76.2%.

Conclusion: Our data compellingly show that CAS quantifies the risk of recurrence in DCIS patients with the highest concordance and provides a novel and innovative tool to tailor their treatment based on their risk profile.

Citation Format: Mittal K, Kaur J, Wei G, Toss MS, Osan RM, Janssen EA, Søiland H, Rakha EA, Rida PC, Aneja R. A quantitative centrosomal amplification score (CAS) predicts local recurrence in ductal carcinoma in situ [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-18-02.

Association between androgen receptor polymorphic CAG and GGC repeat lengths and cryptorchidism: A meta-analysis of case-control studies

INTRODUCTION

Previous studies have revealed the relationship between androgen receptor (AR) CAG and/or GGC polymorphisms and risk of cryptorchidism, yet the results have been elusive and controversial.

AIM

To determine whether AR polymorphic CAG and/or GGC repeats are related to cryptorchidism.

STUDY DESIGN

The relevant studies were obtained from PubMed, Embase, China National Knowledge Infrastructure, and Wanfang. The pooled odds ratios with 95% confidence intervals (CIs) were used to assess the strength of associations. Subgroup analyses were performed based on ethnicity and source of controls. Moreover, Begg's funnel plots and Egger's linear regression test were conducted to determine publication bias.

RESULTS

Eight case-control studies containing 321 patients and 784 normal controls were included. There was a significant association between longer CAG repeats and cryptorchidism risk (weighted mean difference (WMD) = 0.62; 95% CIs 0.06, 1.18; P = 0.031). Moreover, there was a significant association between the longer GGC repeats and cryptorchidism risk (WMD = 0.87; 95% CIs 0.04, 1.74; P = 0.040). There was significant association between the longer CAG repeats and bilateral cryptorchidism (WMD = 0.88; 95% CIs -0.18, 1.94; P = 0.011), while there was no significant association between the longer CAG repeats and unilateral cryptorchidism (WMD = -0.09; 95% CIs -0.50, 0.31; P = 0.554). There were significant associations between the longer GGC repeats and unilateral cryptorchidism (WMD = 0.88; 95% CIs -0.30, 2.05; P = 0.005) and bilateral cryptorchidism (WMD = 1.35; 95% CIs -0.52, 3.21; P = 0.000). Stratifying analysis revealed an association between longer CAG/GGC repeats and cryptorchidism in Caucasian populations from Europe (WMD = 0.73; 95% CIs 0.00, 1.46; P = 0.017), while there was no association with Asian populations.

DISCUSSION

This meta-analysis found that CAG/GGC repeats in the AR gene were longer in cryptorchidism patients compared to controls. Both the longer CAG repeats and GGC repeats in the AR gene were associated with cryptorchidism risk. The longer CAG repeats were associated with bilateral cryptorchidism, whereas the longer GGC repeats were associated with unilateral and bilateral cryptorchidism. Stratifying analysis revealed an association between longer CAG/GGC repeats and cryptorchidism in Caucasian populations from Europe, while there was no association between longer CAG/GGC repeats and cryptorchidism in Asian populations.

CONCLUSION

The CAG/GGC repeats in the AR gene were longer in cryptorchidism than in controls. Longer CAG repeats may play a role in determining bilateral cryptorchidism, and longer GGC repeats may play a role in determining unilateral and bilateral cryptorchidism. These observations were more applicable to Caucasian populations.

Mechanism of Nucleoside Triphosphate Diphosphohydrolase-1-Associated Imbalance in Adenosine Diphosphate Degradation, B-Cell Activation, and Related Injury During Acute Antibody-Mediated Rejection

OBJECTIVE

The objective of this study was to investigate the effect of nucleoside triphosphate diphosphohydrolase-1 (NTPDase1) during acute antibody-mediated rejection (AMR).

METHODS

NTPDase1 overexpression, NTPDase1 knockout, and wild-type nude mice skin graft models were used to induce acute AMR. NTPDase1 expression in B cells, NTPDase1 messenger RNA expression in skin grafts, extracellular adenosine diphosphate (ADP) concentration, B-cell volume and surface antigens expression, average platelet transport rate, and ultrastructure and apoptosis of skin graft cells were investigated.

RESULTS

During acute AMR in nude mice, higher NTPDase1 expression caused lower extracellular ADP concentration, smaller increase in B-cell volume, and major histocompatibility complex II surface antigen expression, suggesting a negative correlation between them; higher NTPDase1 expression also caused slower average platelet transport rate and less severe skin graft injury, suggesting a negative correlation between them. Pretreatment with high-dose exogenous NTPDase1 inhibited platelet activation and protected skin grafts, but it resulted in prolonged bleeding time (by 51.4%) and prolonged coagulation time (by 44.1%).

CONCLUSION

An NTPDase1-associated imbalance in extracellular ADP degradation may contribute to B-cell activation, platelet activation, and more severe skin graft injury in nude mice. Pretreatment with high-dose exogenous NTPDase1 effectively protected skin grafts in nude mice at 1 week, but it increased the risk of bleeding.

Degradation of tetrabromobisphenol A in a paddy soil during sequential anoxic-oxic incubation: Kinetics, metabolites, and potential pathways

Due to the increasing pollution of tetrabromobisphenol A (TBBPA) in paddy soils, it is of great importance to explore the degradation of TBBPA under repeated anoxic-oxic conditions. In the present study, the degradation of TBBPA (kinetics, metabolites and potential pathways) and the influence of low molecular weight organic acid i.e., lactic acid were investigated in a paddy soil during sequential anoxic-oxic incubations. Under the anoxic condition, TBBPA in the non-sterile soils was efficiently debrominated into three intermediates (including tri-BBPA, di-BBPA and mono-BBPA) and bisphenol A (BPA) with a rate constant (k) of 0.0371 d⁻¹ and a half-life (t_1/2) of 60.8 d. The debromination end product (BPA) steadily accumulated. Next, turning to the oxic conditions, the anaerobically accumulated BPA degraded rapidly, while the intermediates and TBBPA were desorbed from the bound residues and were persistent. The detection of tri-BBPA followed by di-BBPA and mono-BBPA thereafter indicated that the dehalogenation of TBBPA was likely a stepwise removal of bromine atoms. A pathway of TBBPA → tri-BBPA → di-BBPA → mono-BBPA → BPA was thus proposed for TBBPA degradation. The degradation of TBBPA and its metabolites was biologically mediated. Moreover, the biodegradation of TBBPA could be significantly accelerated by the addition of lactic acid as an exogenous carbon source and electron donor, with k being increased to 0.0766 d⁻¹ and t_1/2 being shortened to 31.9 d. The information will improve our understanding of biotic process associated with agronomic practices (such as applying organic fertilizers) contributing to TBBPA attenuation in the natural soil environment.

A novel splice site mutation of the PRKAR1A gene, C.440+5 G>C, in a Chinese family with Carney complex

BACKGROUND

Carney complex (CNC) is an extremely rare, multiple endocrine neoplasia syndrome that occurs in an autosomal dominant manner. Mutations in PRKAR1A have been reported to be a common genetic cause of CNC.

METHODS

In this study, we reported a Chinese pedigree of CNC that manifests mainly as spotty skin pigmentation and primary pigmented nodular adrenocortical disease. Whole blood samples of this pedigree were collected for DNA/RNA analysis. Polymerase chain reaction (PCR) and reverse-transcription polymerase chain reaction analyses were performed to amplify the 11 exons and adjacent introns of PRKAR1A. Direct sequencing was used to detect the mutation, and DNA from 70 Han Chinese people was extracted and sequenced as a control to estimate the frequency of the identified mutation.

RESULTS

Within the pedigree, ten patients with CNC were identified, and a novel heterozygous mutation (c.440+5 G>C in intron 4a) was identified in the PRKAR1A gene. PCR amplification of cDNA from the control subjects and patients was performed. Agarose gel electrophoresis showed only one wild-type band in the cDNA corresponding to the former group, whereas an extra band was present in samples from the latter group corresponding to the skipping of exon 4a; this confirms that the variant affects PRKAR1A splicing.

CONCLUSION

In conclusion, the c.440+5 G>C mutation is a new splice site mutation that has not been reported and has the potential to broaden the mutational spectrum of PRKAR1A that is associated with CNC, which would facilitate genetic diagnosis and counseling for CNC.

Comparative symbiotic plasmid analysis indicates that symbiosis gene ancestor type affects plasmid genetic evolution

Rhizobial symbiotic plasmids play vital roles in mutualistic symbiosis with legume plants by executing the functions of nodulation and nitrogen fixation. To explore the gene composition and genetic constitution of rhizobial symbiotic plasmids, comparison analyses of 24 rhizobial symbiotic plasmids derived from four rhizobial genera was carried out. Results illustrated that rhizobial symbiotic plasmids had higher proportion of functional genes participating in amino acid transport and metabolism, replication; recombination and repair; carbohydrate transport and metabolism; energy production and conversion and transcription. Mesorhizobium amorphae CCNWGS0123 symbiotic plasmid - pM0123d had similar gene composition with pR899b and pSNGR234a. All symbiotic plasmids shared 13 orthologous genes, including five nod and eight nif/fix genes which participate in the rhizobia-legume symbiosis process. These plasmids contained nod genes from four ancestors and fix genes from six ancestors. The ancestral type of pM0123d nod genes was similar with that of Rhizobium etli plasmids, while the ancestral type of pM0123d fix genes was same as that of pM7653Rb. The phylogenetic trees constructed based on nodCIJ and fixABC displayed different topological structures mainly due to nodCIJ and fixABC ancestral type discordance. The study presents valuable insights into mosaic structures and the evolution of rhizobial symbiotic plasmids.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study compared 24 rhizobial symbiotic plasmids that included four genera and 11 species, illuminating the functional gene composition and symbiosis gene ancestor types of symbiotic plasmids from higher taxonomy. It provides valuable insights into mosaic structures and the evolution of symbiotic plasmids.

Effect of renal sympathetic denervation on ventricular and neural remodeling

Background

This study assessed the therapeutic effects of renal sympathetic denervation (RDN) on post-myocardial infarction (MI) ventricular remodeling and sympathetic neural remodeling in dogs. The possible mechanisms and optimal time for treatment are discussed.

Methods

We randomly assigned 30 dogs to five groups: RDN 1 week before MI (RDN1w + MI; n = 6), RDN 1 week after MI (MI1w + RDN; n = 6), RDN 2 weeks after MI (MI2w + RDN; n = 6), control (N; n = 6), and MI (n = 6). A canine model of myocardial infarction was established by interventional occlusion with a gelatin sponge via the femoral artery. Brain natriuretic peptide (BNP) and endothelin-1 (ET-1) levels were measured and echocardiography was performed to assess cardiac function and heart size. All dogs were killed at the end of the experiment and samples of cardiac and renal arteries were obtained. The expression of matrix metalloproteinase (MMP)-2 and MMP-9 in cardiac and of tyrosine hydroxylase (TH) in renal arteries was assessed by immunohistochemistry. Sympathetic innervations in the infarction border zone were investigated via Western blotting and real-time PCR.

Results

Left ventricular function in the MI group decreased significantly, while plasma BNP and ET-1 levels as well as MMP-2 and MMP-9 expression increased. Compared with the MI group, the RD groups showed significantly reduced MMP‑2, MMP‑9, TH, and growth-associated protein (GAP) 43 expression in the RDN1w + MI, MI1w + RDN, and MI2w + RDN groups was significantly improved. Additionally, the expression of TH in renal arteries decreased after RDN.

Conclusion

RDN has preventive and therapeutic effects on post-MI ventricular remodeling and sympathetic neural remodeling. The mechanism of RDN is likely mediated through restraint of renal sympathetic nerve activity.

Improvement of zinc substitution in the reactivity of magnetite coupled with aqueous Fe(II) towards nitrobenzene reduction

The reduction of nitrobenzene (NB) by Zn-substituted magnetite coupled with aqueous Fe(II) was studied. A series of Zn-substituted magnetites (Fe_3-xZn_xO₄, x = 0, 0.25, 0.49, 0.74, and 0.99) were synthesized by a coprecipitation method followed by systematic analysis of the variation in structure and physicochemical properties of magnetite using XRD, TEM, TG, BET and XAFS. All of the samples had a spinel structure by Zn substitution. Zn²⁺ primarily occupied the tetrahedral sites, but a portion of them moved to the octahedral sites at higher Zn level. Zn substitution increased the BET specific surface area and surface hydroxyl amount. The electron balance indicated that the NB reduction was primarily through the heterogeneous reaction by Fe_3-xZn_xO₄ and adsorbed Fe(II), where NB in aqueous solution was reduced by structural Fe²⁺ in magnetite recharged by adsorbed Fe(II). Various factors, such as aqueous Fe(II) concentration, magnetite stoichiometry and Zn level, were investigated to illustrate their effects on the reduction processes. Both the rate constant k_obs and electron transfer amount illustrated that Zn substitution generally improved the reduction activity of the Fe_3-xZn_xO₄/Fe(II) system, while overdose of Zn retarded the process. This issue was attributed to the variation in electron conductivity of Fe_3-xZn_xO₄ and Zn²⁺ occupancy.

Photonic ring resonator filters for astronomical OH suppression

Ring resonators provide a means of filtering specific wavelengths from a waveguide, and optionally dropping the filtered wavelengths into a second waveguide. Both of these features are potentially useful for astronomical instruments. In this paper we focus on their use as notch filters to remove the signal from atmospheric OH emission lines from astronomical spectra. We derive the design requirements for ring resonators for OH suppression from theory and finite difference time domain simulations. We find that rings with small radii (< 10 μm) are required to provide an adequate free spectral range, leading to high index contrast materials such as Si and Si₃N₄. Critically coupled rings with high self-coupling coefficients should provide the necessary Q factors, suppression depth, and throughput for efficient OH suppression, but will require post-inscription tuning of the coupling and the resonant wavelengths. The overall prospects for the use of ring resonators in astronomical instruments is promising, provided efficient fibre-chip coupling can be achieved.

Expression and characterization of a lipase-related protein in the malpighian tubules of the Chinese oak silkworm, Antheraea pernyi

Lipases are ubiquitous enzymes in nature, which play a crucial role in fat metabolism by catalyzing the hydrolysis of triacylglycerol to free fatty acids and glycerol. However, reports concerning insect lipase are rare. In this study, we studied the expression and activity of a lipase-related protein from Antheraea pernyi (ApLRP). Recombinant ApLRP was expressed in Escherichia coli cells and used to raise rabbit anti-ApLRP polyclonal antibodies. ApLRP mRNA and protein expression were abundant in the midgut and malpighian tubules, respectively. After challenge with four different microorganisms (E. coli, Beauveria bassiana, Micrococcus luteus and nuclear polyhedrosis virus), the expression levels of ApLRP mRNA in midgut were inducted significantly compared with the control. The different pathogens induced different ApLRP gene expression patterns. The optimum temperature and pH for the enzyme's activity were 35°C and 7.0, respectively. ApLRP activity was stimulated in the presence of Mg2+, Na+, Ca2+ and b-mercaptoethanol; while Zn2+, Cu2+ and Fe3+ inhibited its activity. Detergents such as SDS, glycerol and Tween-20 increased the lipase activity by 20-30%. Our results indicated that ApLRP might play an important role in the innate immunity of insects.

Sea-level haemoglobin concentration is associated with greater exercise capacity in Tibetan males at 4200 m

NEW FINDINGS

What is the topic of this review? Recent developments link relatively lower hemoglobin concentration in Tibetans at high altitude to exercise capacity and components of oxygen transport. What advances does it highlight? Haemoglobin concentration (ranging from 15.2 to 22.9 g dl(-1) ) in Tibetan males was negatively associated with peak oxygen (O2 ) uptake per kilogram, cardiac output and muscle O2 diffusion conductance. Most variance in the peak O2 uptake per kilogram of Tibetan males was attributed to cardiac output, muscle diffusional conductance and arterial partial pressure of CO2 . The mechanisms underlying these differences in oxygen transport in Tibetans require additional analyses. Despite residence at >4000 m above sea level, many Tibetan highlanders, unlike Andean counterparts and lowlanders at altitude, exhibit haemoglobin concentration ([Hb]) within the typical sea-level range. Genetic adaptations in Tibetans are associated with this relatively low [Hb], yet the functional relevance of the lower [Hb] remains unknown. To address this, we examined each major step of the oxygen transport cascade [ventilation (VE), cardiac output (QT) and diffusional conductance in lung (DL) and muscle (DM)] in Tibetan males at maximal exercise on a cycle ergometer. Ranging from 15.2 to 22.9 g dl(-1) , [Hb] was negatively associated with peak O2 uptake per kilogram (r = -0.45, P < 0.05) and both cardiac output (QT/kg: r = -0.54, P < 0.02) and muscle O2 diffusion conductance (DM/kg: r = -0.44, P < 0.05) but not ventilation, arterial partial pressure of O2 or pulmonary diffusing capacity. Most variance in peak O2 uptake per kilogram was attributed to QT, DM and arterial partial pressure of CO2 (r(2)  = 0.90). In summary, lack of polycythaemia in Tibetans is associated with increased exercise capacity, which is explained by elevated cardiac, muscle and, to a small extent, ventilatory responses rather than pulmonary gas exchange. Whether lower [Hb] is the cause or result of these changes in O2 transport or is causally unrelated will require additional study.

The variation of cationic microstructure in Mn-doped spinel ferrite during calcination and its effect on formaldehyde catalytic oxidation

In this study, a series of Mn substituted spinel ferrites calcinated at different temperatures were used as catalysts for the oxidation of formaldehyde (HCHO). X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy and H2 temperature-programmed reduction were conducted to characterize the structure and physico-chemical properties of catalysts, which were affected by calcination in the range of 200-600°C. Results show that all the ferrites were with spinel structure, and those calcinated in the range of 300-600°C were in the phase of maghemite. The calcination changed the valence and distribution of Mn and Fe on the ferrite surface, and accordingly the reducibility of ferrites. The HCHO catalytic oxidation test showed that with the increase of calcination temperature, the activity was initially improved until 400°C, but then decreased. The variation of HCHO conversion performance was well positively correlated to the variation of reduction temperature of surface Mn(4+) species. The remarkable effect of calcination on the catalytic activity of Mn-doped spinel ferrites for HCHO oxidation was discussed in view of reaction mechanism and variations in cationic microstructure of Mn-doped ferrites.

What hides behind the MASC: clinical response and acquired resistance to entrectinib after ETV6-NTRK3 identification in a mammary analogue secretory carcinoma (MASC)

Here, we describe the dramatic response of a patient with an ETV6-NTRK3-driven mammary analogue secretory carcinoma to treatment with a pan-Trk inhibitor, and the development of acquired resistance linked to a novel NTRK3 mutation that interferes with drug binding. This case emphasizes how molecular profiling can identify therapies for rare diseases and dissect mechanisms of drug resistance.

Background

Mammary analogue secretory carcinoma (MASC) is a recently described pathologic entity. We report the case of a patient with an initial diagnosis of salivary acinic cell carcinoma later reclassified as MASC after next-generation sequencing revealed an ETV6-NTRK3 fusion.

Patients and methods

This alteration was targeted with the pan-Trk inhibitor entrectinib (Ignyta), which possesses potent in vitro activity against cell lines containing various NTRK1/2/3 fusions.

Results

A dramatic and durable response was achieved with entrectinib in this patient, followed by acquired resistance that correlated with the appearance of a novel NTRK3 G623R mutation. Structural modeling predicts that this alteration sterically interferes with drug binding, correlating to decreased sensitivity to drug inhibition observed in cell-based assays.

Conclusions

This first report of clinical activity with TrkC inhibition and the development of acquired resistance in an NTRK3-rearranged cancer emphasize the utility of comprehensive molecular profiling and targeted therapy for rare malignancies (NCT02097810).

Isolation and characterisation of cDNA encoding a wheat heavy metal-associated isoprenylated protein involved in stress responses

In cells, metallochaperones are important proteins that safely transport metal ions. Heavy metal-associated isoprenylated plant proteins (HIPPs) are metallochaperones that contain a metal binding domain and a CaaX isoprenylation motif at the carboxy-terminal end. To investigate the roles of wheat heavy metal-associated isoprenylated plant protein (TaHIPP) genes in plant development and in stress responses, we isolated cDNA encoding the wheat TaHIPP1 gene, which contains a heavy metal-associated domain, nuclear localisation signals and an isoprenylation motif (CaaX motif). Quantitative real-time PCR analysis indicated that the TaHIPP1 gene was differentially expressed under biotic and abiotic stresses. Specifically, TaHIPP1 expression was up-regulated by ABA exposure or wounding. Additionally, TaHIPP1 over-expression in yeast (Schizosaccharomyces pombe) significantly increased the cell growth rate under Cu(2+) and high salinity stresses. The nuclear localisation of the protein was confirmed with confocal laser scanning microscopy of epidermal onion cells after particle bombardment with chimeric TaHIPP1-GFP constructs. In addition, TaHIPP1 was shown to enhance the susceptibility of wheat to Pst as determined by virus-induced gene silencing. These data indicate that TaHIPP1 is an important component in defence signalling pathways and may play a crucial role in the defence response of wheat to biotic and certain abiotic stresses.