The p53-inducible CLDN7 regulates colorectal tumorigenesis and has prognostic significance

Most colorectal cancer (CRC) are characterized by allele loss of the genes located on the short arm of chromosome 17 (17p13.1), including the tumor suppressor p53 gene. Although important, p53 is not the only driver of chromosome 17p loss. In this study, we explored the biological and prognostic significance of genes around p53 on 17p13.1 in CRC. The Cancer Genome Atlas (TCGA) were used to identify differentially expressed genes located between 1000 kb upstream and downstream of p53 gene. The function of CLDN7 was evaluated by both in vitro and in vivo experiments. Quantitative real-time PCR, western blot, and promoter luciferase activity, immunohistochemistry were used to explore the molecular drivers responsible for the development and progression of CRC. The results showed that CLDN7, located between 1000 kb upstream and downstream of p53 gene, were remarkably differentially expressed in tumor and normal tissues. CLDN7 expression also positively associated with p53 level in different stages of the adenoma-carcinoma sequence. Both in vitro and in vivo assays showed that CLDN7 inhibited cell proliferation in p53 wild type CRC cells, but had no effects on p53 mutant CRC cells. Mechanistically, p53 could bind to CLDN7 promoter region and regulate its expression. Clinically, high CLDN7 expression was negatively correlated with tumor size, invasion depth, lymphatic metastasis and AJCC III/IV stage, but was positively associated with favorable prognosis of CRC patients. Collectively, our work uncovers the tumor suppressive function for CLDN7 in a p53-dependent manner, which may mediate colorectal tumorigenesis induced by p53 deletion or mutation.

CHAF1A overexpression in human retinoblastoma promotes cell proliferation and suppresses apoptosis

PURPOSE

Retinoblastoma causes significant human mortality especially in children. Although retinoblastoma may be treated if detected at early stage, however, it becomes destructive at advanced stages. The treatment involves surgery and chemotherapy. However, the chemotherapeutic agents have severe adverse effects. Therefore, development of viable drugs and identification of novel molecular therapeutic targets may enable efficient management of retinoblastoma. This study was designed to examine the expression profile of Chromatin Assembly Factor-1 (CHAF1A) and explore its therapeutic implications in retinoblastoma.

METHODS

The expression of CHAF1A was determined by qRT-PCR. MTT assay was used for the determination of the cell viability. Apoptosis was detected by acridine orange (AO)/ethidium bromide (EB) and annexin V/propidium iodide (PI) assay. Cell cycle analysis was determined by flow cytometery. Protein expression was determined by western blot analysis.

RESULTS

The results showed that CHAF1A is significantly upregulated in human retinoblastoma, with 7.3 folds upregulation in retinoblastoma cells relative to normal cells. Knockdown of CHAF1A resulted in significant decline in the viability of the RB355 retinoblastoma cells. The flow cytometric analysis showed that knockdown of CHAF1A caused arrest of the RB355 cells at G0/G1 phase of the cell cycle. This was also linked with significant downregulation of cyclin D1 and cyclin E1. The AO/EB staining assay showed that CHAF1A knockdown promotes apoptosis which is associated with downregulation of Bcl-2 and upregulation of Bax.

CONCLUSION

Taken together, these results suggest that CHAF1A is upregulated in retinoblastoma and regulates its proliferation and apoptosis. As such CHAF1A may act as biomarker as well as therapeutic target for the management of retinoblastoma.

Light-Induced Self-Escape of Spherical Nucleic Acid from Endo/Lysosome for Efficient Non-Cationic Gene Delivery

Developing non-cationic gene carriers and achieving efficient endo/lysosome escape of functional nucleic acids in cytosol are two major challenges faced by the field of gene delivery. Herein, we demonstrate the concept of self-escape spherical nucleic acid (SNA) to achieve light controlled non-cationic gene delivery with sufficient endo/lysosome escape capacity. In this system, Bcl-2 antisense oligonucleotides (OSAs) were conjugated onto the surface of aggregation-induced emission (AIE) photosensitizer (PS) nanoparticles to form core-shell SNA. Once the SNAs were taken up by tumor cells, and upon light irradiation, the accumulative ¹ O₂ produced by the AIE PSs ruptured the lysosome structure to promote OSA escape. Prominent in vitro and in vivo results revealed that the AIE-based core-shell SNA could downregulate the anti-apoptosis protein (Bcl-2) and induce tumor cell apoptosis without any transfection reagent.

MK-8719, a Novel and Selective O-GlcNAcase Inhibitor That Reduces the Formation of Pathological Tau and Ameliorates Neurodegeneration in a Mouse Model of Tauopathy

Deposition of hyperphosphorylated and aggregated tau protein in the central nervous system is characteristic of Alzheimer disease and other tauopathies. Tau is subject to O-linked N-acetylglucosamine (O-GlcNAc) modification, and O-GlcNAcylation of tau has been shown to influence tau phosphorylation and aggregation. Inhibition of O-GlcNAcase (OGA), the enzyme that removes O-GlcNAc moieties, is a novel strategy to attenuate the formation of pathologic tau. Here we described the in vitro and in vivo pharmacological properties of a novel and selective OGA inhibitor, MK-8719. In vitro, this compound is a potent inhibitor of the human OGA enzyme with comparable activity against the corresponding enzymes from mouse, rat, and dog. In vivo, oral administration of MK-8719 elevates brain and peripheral blood mononuclear cell O-GlcNAc levels in a dose-dependent manner. In addition, positron emission tomography imaging studies demonstrate robust target engagement of MK-8719 in the brains of rats and rTg4510 mice. In the rTg4510 mouse model of human tauopathy, MK-8719 significantly increases brain O-GlcNAc levels and reduces pathologic tau. The reduction in tau pathology in rTg4510 mice is accompanied by attenuation of brain atrophy, including reduction of forebrain volume loss as revealed by volumetric magnetic resonance imaging analysis. These findings suggest that OGA inhibition may reduce tau pathology in tauopathies. However, since hundreds of O-GlcNAcylated proteins may be influenced by OGA inhibition, it will be critical to understand the physiologic and toxicological consequences of chronic O-GlcNAc elevation in vivo. SIGNIFICANCE STATEMENT: MK-8719 is a novel, selective, and potent O-linked N-acetylglucosamine (O-GlcNAc)-ase (OGA) inhibitor that inhibits OGA enzyme activity across multiple species with comparable in vitro potency. In vivo, MK-8719 elevates brain O-GlcNAc levels, reduces pathological tau, and ameliorates brain atrophy in the rTg4510 mouse model of tauopathy. These findings indicate that OGA inhibition may be a promising therapeutic strategy for the treatment of Alzheimer disease and other tauopathies.

FRI0271 IMPACT OF HLA-B27 STATUS ON CLINICAL OUTCOMES AMONG PATIENTS WITH ANKYLOSING SPONDYLITIS TREATED WITH SECUKINUMAB

Background:

Ankylosing spondylitis (AS) is strongly associated with the genetic marker HLA-B27. Approximately 80%-90% of white patients with AS express HLA-B27 compared with < 8% of the general population. In patients with AS, negative HLA-B27 status is a predictor of worse response to TNFis.1The impact of HLA-B27 status on clinical efficacy of secukinumab, a fully human monoclonal antibody that selectively inhibits IL-17A, has not been studied.

Objectives:

To analyze the impact of HLA-B27 status on clinical outcomes at Week 16 in patients with AS treated with secukinumab vs placebo.

Methods:

Patients with AS were pooled from the MEASURE 1-4 studies (NCT01358175,NCT01649375,NCT02008916, andNCT02159053) and stratified by HLA-B27 status. All trials included patients who received secukinumab 150 mg every 4 weeks with or without an initial loading dose (10 mg/kg IV at Weeks 0, 2, 4 or 150 mg SC at Weeks 0, 1, 2, and 3) or placebo control. MEASURE 3 included patients receiving secukinumab 300 mg every 4 weeks following the initial IV loading dose. Efficacy at Week 16 was determined by the proportion of patients achieving ASAS20/40, ASAS5/6, ASAS partial remission, BASDAI50, ASDAS-CRP < 2.1, ASDAS-CRP < 1.3, and improvement in Patient Global Assessment (VAS) and total spinal/back pain (VAS) scores. In MEASURE 1, 2, and 4, quality of life (QOL) was assessed at Week 16 by the SF-36 PCS, SF-36 MCS, and ASQOL. ASAS, BASDAI, and ASDAS-CRP responses were analyzed by nonresponder imputation, and all other outcomes by mixed models for repeated measures. For hypothesis generation, outcomes at Week 16 with secukinumab vs placebo within HLA-B27 strata were compared by logistic regression analysis without adjustment for multiple comparisons.

Results:

Baseline characteristics were balanced across treatment groups, although more HLA-B27+ patients than HLA-B27− patients were male (71%-73% vs 43%-50%). HLA-B27+ patients receiving any dose of secukinumab were significantly more likely to achieve ASAS, BASDAI50, and ASDAS-CRP responses vs those receiving placebo (P< .05; Figure 1). HLA-B27− patients receiving secukinumab 300 mg were significantly more likely to achieve ASAS40, ASAS partial remission (Figure 1A), and BASDAI50 (Figure 1B) responses than those receiving placebo (P< .05). Patients receiving any dose of secukinumab were more likely to achieve ASAS5/6 and ASDAS-CRP < 2.1 than those receiving placebo, regardless of HLA-B27 status (P< .05; Figure 1B). All secukinumab-treated patients experienced significant improvement in Patient Global Assessment at Week 16 vs placebo, regardless of HLA-B27 status, while only HLA-B27+ patients experienced significant reduction in total spinal/back pain vs placebo (P< .05; Figure 2A). Numerical improvements in QOL were observed in all patients receiving secukinumab 150 mg vs placebo; these reached significance for HLA-B27+ patients (Figure 2B).

Conclusion:

Secukinumab is effective in patients with AS regardless of HLA-B27 status; HLA-B27+ patients may derive increased therapeutic benefit compared with HLA-B27− patients.

Reference:

[1]Alazmi M, et al.Arthritis Care Res (Hoboken). 2018;70:1393-9.

Acknowledgments:

This study was funded by Novartis Pharmaceuticals Corporation. The authors thank Rich Karpowicz, PhD, of Health Interactions, Inc, for providing medical writing support/editorial support, which was funded by Novartis Pharmaceuticals Corporation, East Hanover, NJ, in accordance with Good Publication Practice (GPP3) guidelines (http://www.ismpp.org/gpp3).

Disclosure of Interests:

Atul Deodhar Grant/research support from: AbbVie, Eli Lilly, GSK, Novartis, Pfizer, UCB, Consultant of: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB, Speakers bureau: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB, Philip J Mease Grant/research support from: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – grant/research support, Consultant of: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – consultant, Speakers bureau: Abbott, Amgen, Biogen Idec, BMS, Eli Lilly, Genentech, Janssen, Pfizer, UCB – speakers bureau, Denis Poddubnyy Grant/research support from: AbbVie, MSD, Novartis, and Pfizer, Consultant of: AbbVie, Bristol-Myers Squibb, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Eli Lilly, MSD, Novartis, Pfizer, Roche, UCB, Renato Calheiros Shareholder of: Novartis, Employee of: Novartis, Xiangyi Meng Shareholder of: Novartis, Employee of: Novartis, Vibeke Strand Consultant of: AbbVie, Amgen, Biogen, Celltrion, Consortium of Rheumatology Researchers of North America, Crescendo Bioscience, Eli Lilly, Genentech/Roche, GlaxoSmithKline, Hospira, Janssen, Merck, Novartis, Pfizer, Regeneron Pharmaceuticals, Inc., Sanofi, UCB, Marina Magrey Grant/research support from: AbbVie, Amgen, and UCB, Consultant of: Eli Lilly and Novartis

THU0397 SYMPTOMS OF PERIPHERAL ARTHRITIS ARE SIGNIFICANTLY IMPROVED IN PATIENTS WITH ANKYLOSING SPONDYLITIS TREATED WITH SECUKINUMAB

Background:

Ankylosing spondylitis (AS) is a chronic inflammatory disease of the axial skeleton associated with pain, stiffness, and disability.1Up to 66% of patients (pts) with AS may also have peripheral involvement, including swollen and tender joints (STJs),2,3which are associated with worse overall disease activity.4A previous analysis showed that secukinumab, a selective inhibitor of interleukin 17A, led to significant improvements in efficacy outcomes vs placebo, regardless of peripheral joint involvement.3However, the effect of secukinumab on symptoms of peripheral arthritis in pts with AS was not assessed.

Objectives:

The objective of this analysis was to assess changes in peripheral symptoms in pts with AS treated with secukinumab vs placebo.

Methods:

Data from pts with active AS and peripheral symptoms who were enrolled in MEASURE 1 (NCT01358175), 2 (NCT01649375), 3 (NCT02008916), and 4 (NCT02159053) were pooled in this post hoc, hypothesis-generating analysis. No adjustments for multiple comparisons were made. Pts with peripheral symptoms were identified by the presence of STJs, based on 44-joint counts at baseline (BL). Pts received subcutaneous (SC) secukinumab every 4 weeks at doses of 300 mg with an intravenous (IV) loading dose (MEASURE 3 only), 150 mg with an IV or SC loading dose, or placebo. Treatment response through Week 16 was assessed based on the proportions of pts who achieved improvements of 20%, 50%, 70%, or 100% in the number of swollen and number of tender joints and improvements in the BASDAI score for question 3 and Patient Global Assessment (PGA). Changes in the number of swollen and number of tender joints were assessed in pts with swollen or tender joints at BL, respectively.

Results:

This pooled analysis included 560 pts with AS and STJs at BL (Table). At Week 16, treatment with secukinumab led to significantly greater proportions of pts achieving reductions in the number of swollen (Fig 1A) or tender (Fig 1B) joints compared with placebo; the treatment effect was more pronounced in reduction of swollen joints. Furthermore, a greater proportion of secukinumab-treated pts achieved complete resolution of swollen or tender joints vs placebo (Fig 1). Secukinumab also led to significant improvements in peripheral pain/swelling (Fig 2A) and disease activity (Fig 2B) vs placebo, as assessed using BASDAI question 3 and the PGA, respectively.

Table.

Patient Characteristics at Baseline

SecukinumabPlacebo (n = 252)300 mg (n = 52)150 mg (n = 256)Age, mean, y43.643.744.9Time since diagnosis, mean, y5.67.27.3Male, %63.562.157.5PGA of Disease Activity, mean, mm73.471.770.1BASDAI question 3, mean6.36.66.4Swollen 44-joint count, mean1.92.62.5Tender 44-joint count, mean7.17.87.9

Conclusion:

In parallel with its previously reported efficacy in axial symptoms,3secukinumab led to significant improvements in symptoms of peripheral arthritis in pts with AS. Significant improvements were seen in both tender and swollen joints.

References:

[1]Braun J, Sieper J.Lancet. 2007;369:1379-1390.

[2]de Winter JJ, et al.Arthritis Res Ther. 2016;18:196.

[3]Mease P, et al.Arthritis Rheumatol. 2019;71(suppl 10):1553.

[4]de Winter JJ, et al.RMD Open. 2019;5:e000802.

Acknowledgments:

This study was funded by Novartis Pharmaceuticals Corporation, East Hanover, NJ. The authors thank Amos Race, PhD, of ArticulateScience LLC, Hamilton, NJ, USA, for providing medical writing/editorial support, which was funded by Novartis Pharmaceuticals Corporation, East Hanover, NJ, USA, in accordance with Good Publication Practice (GPP3) guidelines (http://www.ismpp.org/gpp3).

Disclosure of Interests:

Philip J Mease Grant/research support from: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – grant/research support, Consultant of: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – consultant, Speakers bureau: Abbott, Amgen, Biogen Idec, BMS, Eli Lilly, Genentech, Janssen, Pfizer, UCB – speakers bureau, Atul Deodhar Grant/research support from: AbbVie, Eli Lilly, GSK, Novartis, Pfizer, UCB, Consultant of: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB, Speakers bureau: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myer Squibb (BMS), Eli Lilly, GSK, Janssen, Novartis, Pfizer, UCB, Renato Calheiros Shareholder of: Novartis, Employee of: Novartis, Xiangyi Meng Shareholder of: Novartis, Employee of: Novartis, Todd Fox Shareholder of: Novartis, Employee of: Novartis, Xenofon Baraliakos Grant/research support from: Grant/research support from: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Consultant of: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Speakers bureau: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen

Benthic foraminifera and its response to heavy metal pollution: A case study from Liaodong Bay, China

Benthic foraminifera can be used as an environmental bioindicator, especially in the polluted environment where their sensitivity to pollutants may be expressed by a modification in the assemblage. Based on the quantitative and qualitative analysis of 189 surface sediment samples in Liaodong Bay, 76 benthic foraminifera species which belong to 40 genera were recognized. Q-mode factor analysis was made for the 32 benthic foraminifera species, and three assemblages are recognized: Ammonia aomoriensis- Cribroelphidium magellanicum- Protelphidium tuberculatum; Textularia foliacea- Polskiammina asiatica; and Rotalidium annectens- Buccella frigida. To study the effects of heavy metal elements on benthic foraminifera fauna, seven heavy metals elements have been analyzed in all the surface sediment samples, the results show that the heavy metal elements in Liaodong Bay are mainly distributed in Jinzhou Port, and that the overall characteristics are high in northwest and low in southeast. The distribution of foraminifera and heavy metals elements reveals that there is a significant correlation between them. Cribroelphidium magellanicum and Protelphidium tuberculatum have maintained a high level in heavy metal enrichment areas, and may be used as an indicator of heavy metal contamination along the coast of Liaodong Bay.

Transcriptional regulation of heat shock protein 70 genes by class I histone deacetylases in the red flour beetle, Tribolium castaneum

The regulatory function of histone acetylation in the expression of genes encoding heat shock proteins (Hsps) has been documented in Drosophila melanogaster; however, knowledge of the role of acetylation in modulating Hsps in other insect pests is limited. In this study, two full-length cDNAs encoding inducible Hsp70 (designated TcHsp70) and heat shock cognate 70 (TcHsc70) were isolated and characterized in the red flour beetle, Tribolium castaneum. TcHsp70 and TcHsc70 cDNAs were 2256 and 2132 bp and encoded 1941- and 1893-bp open reading frames, respectively. The deduced TcHsp70 and TcHsc70 proteins contained 646 and 630 amino acids, respectively, and contained sequences typical of the Hsp70 family, including the EEVD motif for cytoplasmic localization. Expression patterns after heat shock indicated that TcHsp70 was strongly heat-inducible, whereas the expression level of TcHsc70 remained unchanged under heat shock. RNA interference-mediated knock-down of three genes encoding class I histone deacetylases differentially influenced both basal and heat shock inducible expression of TcHsp70 and TcHsc70, suggesting the involvement of histone acetylation in epigenetic regulation of Hsp70 transcription in T. castaneum.

Inhibition of microRNA-875-5p promotes radioiodine uptake in poorly differentiated thyroid carcinoma cells by upregulating sodium-iodide symporter

BACKGROUND AND AIM

Poorly differentiated thyroid carcinoma (PDTC) is an endocrine malignancy that is challenging to treat due to its limited radioiodine uptake. microRNAs (miRNAs or miRs) have been shown to be useful in treating many types of tumors, including PDTC. This study aims to evaluate the potential effect of miR-875-5p on the radioiodine uptake of PDTC and to clarify the underlying mechanisms.

METHODS

Expression of miR-875-5p and sodium-iodide symporter (NIS) in tissues and cell lines was determined using RT-qPCR. The binding relationship between miR-875-5p and NIS was predicted through in silico analysis and verified by dual-luciferase reporter gene assay. A series of miR-875-5p mimic, miR-875-5p inhibitor, shRNA against NIS, and overexpressed NIS plasmids were introduced into PDTC cells. We then evaluated the cell viability, colony formation, apoptosis, and radioiodine uptake of each PDTC sample via CCK-8 assay, clonogenic assay, flow cytometry, and γ counter, respectively.

RESULTS

miR-875-5p was found to be highly expressed, but NIS was poorly expressed in DTC tissues and PDTC cell lines. NIS was verified to be a target gene of miR-875-5p. Upregulation of miR-875-5p was found to induce PDTC cell proliferation, and reduce apoptosis and radioiodine uptake in vitro through down-regulation of NIS. In an in vivo orthotopic model, the enhancement of miR-875-5p led to the reduction of NIS expression and radioiodine uptake in the thyroid tumors.

CONCLUSIONS

Altogether, the findings of the current study suggest that down-regulated miR-875-5p expression could promote its target gene NIS to increase radioiodine uptake in PDTC, constituting a preventive strategy against PDTC.

fMRI study of olfactory processing in mice under three anesthesia protocols: Insight into the effect of ketamine on olfactory processing

Functional magnetic resonance imaging (fMRI) is a valuable tool for studying neural activations in the central nervous system of animals due to its wide spatial coverage and non-invasive nature. However, the advantages of fMRI have not been fully realized in functional studies in mice, especially in the olfactory system, possibly due to the lack of suitable anesthesia protocols with spontaneous breathing. Since mice are widely used in biomedical research, it is desirable to evaluate different anesthesia protocols for olfactory fMRI studies in mice. Dexmedetomidine (DEX) as a sedative/anesthetic has been introduced to fMRI studies in mice, but it has a limited anesthesia duration. To extend the anesthesia duration, DEX has been combined with a low dose of isoflurane (ISO) or ketamine (KET) in previous functional studies in mice. In this report, olfactory fMRI studies were performed under three anesthesia protocols (DEX alone, DEX/ISO, and DEX/KET) in three different groups of mice. Isoamyl-acetate was used as an odorant, and the odorant-induced neural activations were measured by blood oxygenation-level dependent (BOLD) fMRI. BOLD fMRI responses were observed in the olfactory bulb (OB), anterior olfactory nuclei (AON), and piriform cortex (Pir). Interestingly, BOLD fMRI activations were also observed in the prefrontal cortical region (PFC), which are most likely caused by the draining vein effect. The response in the OB showed no adaptation to either repeated odor stimulations or continuous odor exposure, but the response in the Pir showed adaptation during the continuous odor exposure. The data also shows that ISO suppresses the olfactory response in the OB and AON, while KET enhances the olfactory response in the Pir. Thus, DEX/KET should be an attractive anesthesia for olfactory fMRI in mice.

PRDX2 plays an oncogenic role in esophageal squamous cell carcinoma via Wnt/β-catenin and AKT pathways

PURPOSE

To investigate the role of PRDX2 in esophageal carcinoma (ESCA).

METHODS

The expression of PRDX2 was detected in ESCA tissues. And PRDX2 expression in two ESCA cell lines was knocked down. Cell proliferation, metastasis and invasion were detected in these cells.

RESULTS

Here, we found that PRDX2 expression was significantly increased in ESCA tissues and was associated with a poor prognosis in ESCA patients. In addition, PRDX2 expression was significantly associated with pathological grading, infiltration degree and 5-year survival time in ESCA patients. Next, we knocked down PRDX2 expression by PRDX2-shRNA transfection in two ESCA cell lines, Eca-109 and TE-1. Proliferation analysis indicated that in vitro PRDX2 knockdown decreased growth and clone formation of ESCA cells. Scratch and transwell assays indicated that cell migration and invasion were significantly inhibited by PRDX2 knockdown. In addition, PRDX2 knockdown inhibited cell cycle of ESCA cells and down-regulated Cyclin D1-CDK4/6. Moreover, PRDX2 knockdown regulated proteins involved in mitochondrial-dependent apoptosis, including increased Bax and Caspase9/3 and decreased Bcl2. Mechanism investigation indicated that PRDX2 knockdown led to inactivation of Wnt/β-catenin and AKT pathways.

CONCLUSIONS

Our data suggest that PRDX2 may function as an oncogene in the development of ESCA via regulating Wnt/β-catenin and AKT pathways. Our study fills a gap in the understanding of the role of PRDX2 in ESCA and provides a potential target for ESCA treatment.

Hybrid Nanospheres to Overcome Hypoxia and Intrinsic Oxidative Resistance for Enhanced Photodynamic Therapy

Photodynamic therapy (PDT) has been a well-accepted clinical treatment for malignant tumors owing to its noninvasiveness and high spatiotemporal selectivity. However, the efficiency of PDT is still severely hindered by an inherent aggregation-caused quenching (ACQ) effect of traditional photosensitizers (PSs), the presence of B-cell lymphoma 2 (Bcl-2), an antiapoptosis protein in cells, and hypoxia in the tumor microenvironment. To address these issues, hybrid nanospheres containing Fe³⁺, aggregation-induced emission (AIE) PS, and Bcl-2 inhibitor of sabutoclax were constructed via coordination-driven self-assembly in aqueous media. Once the hybrid nanospheres are taken up by tumor cells, intracellular O₂ concentration is observed to increase via Fenton reaction driven by Fe³⁺, whereas intracellular PDT resistance of the AIE PS was mitigated by sabutoclax. The design of the multifunctional hybrid nanospheres demonstrates a prospective nanoplatform for image-guided enhanced PDT of tumors.

MiR-107 confers chemoresistance to colorectal cancer by targeting calcium-binding protein 39

Background

Chemoresistance remains a critical event that accounts for colorectal cancer (CRC) lethality. The aim of this study is to explore the ability of dichloroacetate (DCA) to increase chemosensitivity in CRC and the molecular mechanisms involved.

Methods

The effects of combination treatment of DCA and oxaliplatin (L-OHP) were analysed both in vitro and in vivo. The DCA-responsive proteins in AMPK pathway were enriched using proteomic profiling technology. The effect of DCA on CAB39–AMPK signal pathway was analysed. In addition, miRNA expression profiles after DCA treatment were determined. The DCA-responsive miRNAs that target CAB39 were assayed. Alterations of CAB39 and miR-107 expression were performed both in vitro and on xenograft models to identify miR-107 that targets CAB39–AMPK–mTOR signalling pathway.

Results

DCA increased L-OHP chemosensitivity both in vivo and in vitro. DCA could upregulate CAB39 expression, which activates the AMPK/mTOR signalling pathway. CAB39 was confirmed to be a direct target of miR-107 regulated by DCA. Alterations of miR-107 expression were correlated with chemoresistance development in CRC both in vitro and in vivo.

Conclusion

These findings suggest that the miR-107 induces chemoresistance through CAB39–AMPK–mTOR pathway in CRC cells, thus providing a promising target for overcoming chemoresistance in CRC.

Impaired geometry, volumetric density, and microstructure of cortical and trabecular bone assessed by HR-pQCT in both sporadic and MEN1-related primary hyperparathyroidism

This study evaluated bone features of PHPT using HR-pQCT. The results showed both cortical and trabecular bones were significantly impaired in PHPT patients. Male and female PHPT patients suffered similar damages in bone. HR-pQCT indices were not observed to differ in MEN1 and sporadic PHPT patients.

INTRODUCTION

High-resolution peripheral quantitative CT is a novel imaging technique used to separately assess trabecular and cortical bone status of the radius and tibia in vivo. Using HR-pQCT, we aimed to evaluate bone features of primary hyperparathyroidism patients in a Chinese population and reveal similarities and differences in bone features in multiple endocrine neoplasia type 1-related PHPT and sporadic PHPT patients in the Chinese population.

METHODS

A case-control study was designed. In 58 PHPT patients and 58 sex- and age-matched healthy controls, the distal radius and tibia were scanned using HR-pQCT. Areal bone mineral density (aBMD) was also determined in PHPT patients using dual-energy X-ray absorptiometry (DXA).

RESULTS

In comparison with controls, PHPT patients were observed to exhibit reduced volumetric BMD at the cortical and trabecular compartments, thinner cortices, and more widely spaced trabeculae. Significant differences were still observed when comparing data of female and male patients with age-matched controls separately. MHPT patients (n = 11) were found to have lower aBMD Z-scores in the lumbar spine, trochanteric region, and total hip compared with sporadic PHPT patients (n = 47), while no differences were observed in HR-pQCT indices between the two groups. In multiple linear regression models, no significant correlations were identified between PTH and HR-pQCT indices. However, height was found to positively correlate with HR-pQCT-derived trabecular indices at both the radius and tibia.

CONCLUSIONS

PHPT affects geometry, volumetric density, and microstructure in both the cortical and trabecular bones in both male and female Chinese patients. MHPT patients were observed to have reduced aBMD as determined by DXA in the lumbar spine and hip in comparison with sporadic PHPT patients. However, HR-pQCT indices were not observed to differ.

Isolation and characterization of Salmonella in pork samples collected from retail and wholesale markets in each season from 2016 to 2018 in Wuhan, China

AIMS

To investigate the prevalence and characteristics of Salmonella in pork on sale in Wuhan, Central China.

METHODS AND RESULTS

A total of 4744 pork samples were collected from retail or wholesale markets in each season from 2016 to 2018. The samples showed an overall Salmonella prevalence of 19·54% (927/4744), among which the samples collected in 2017 (21·67%, 428/1975) possessed a significantly higher prevalence than those collected in 2016 (18·61%, 209/1123) (P = 0·047) or 2018 (17·51%, 290/1656) (P = 0·002), and the samples collected in winter showed the lowest prevalence (15·86%, 177/1116). The Salmonella prevalence was significantly higher among samples from retail markets (25·68%, 283/1102) than wholesale markets (17·68%, 644/3642) (P = 0·000). Antimicrobial resistance of 922 Salmonella strains was tested by determining the minimal inhibitory concentrations using a broth microdilution method. The strains revealed that 98·92% (912/922) were resistant to at least one of the antimicrobial agents, and 80·04% (738/922) were resistant to three or more antimicrobials (MDR). Resistance to sulfamethoxazole/trimethoprim (89·91%), tetracycline (87·20%) and ampicillin (71·69%) was predominant. The proportion of MDR strains in 2017 (93·62%, 396/423) was significantly higher than that in 2016 (63·16%, 132/209) (P = 0·000) or 2018 (69·66%, 202/290) (P = 0·000). No significant difference was observed in the proportions of MDR strains between wholesale markets (76·07%, 213/280) and retail markets (80·53%, 517/642) (P = 0·075). Multi-locus sequence typing for 554 of the isolates revealed 20 different sequence types (STs), among which ST40 (38·27%, 212/554), ST34 (18·41%, 102/554) and ST469 (14·46%, 79/554) were dominant.

CONCLUSIONS

A high risk of Salmonella prevalence and antimicrobial resistance was observed in pork in Wuhan. The risk varies between different sampling years, seasons and market types.

SIGNIFICANCE AND IMPACT OF THE STUDY

Providing baseline data on Salmonella contamination in pork on sale in Central China.

Aβ1-42 regulates astrocytes through JNK/AP-1 pathway

OBJECTIVE

In Alzheimer's disease (AD), astrocytes are generally found in the surrounding of senile plaques participating in the production of phagocytosis and the removal of toxic compounds such as Aβ. This study aimed at investigating the effect of Aβ1-42 on astrocytes.

MATERIALS AND METHODS

Cellular viability of primary cultured astrocytes was analyzed using CCK-8 assay. Quantitative Real-time PCR was used to assess the mRNA expression of JNK and AP-1. The proteins of JNK/AP-1 pathway were investigated using Western blot.

RESULTS

Our findings showed that Aβ1-42 inhibited cell viability and promoted apoptosis in astrocytes in primary culture. Additionally, Aβ1-42 increased the mRNA expression level of AP-1, but had no effect on the expression of JNK. Furthermore, Aβ1-42 increased the protein expression of p-JNK, p-c-jun and Fra-1 and the ratio of p-c-jun/c-jun and p-JNK/JNK.

CONCLUSIONS

We showed that Aβ1-42 promoted cell apoptosis in astrocytes in primary culture. Furthermore, Aβ1-42 activated JNK/AP-1 pathway through promoting the phosphorylation of JNK, c-jun and Fra-1 expression, then inducing cell apoptosis.