[β-catenin nuclear translocation represses thyroid cancer stem cells differentiating into cells with sodium-iodine symporter functional expression]

Objective: To confirm whether β-catenin nuclear translocation in thyroid cancer stem cells can differentiate into thyroid cancer cells without functional membrane expression of sodium-iodine transporter (NIS) and be resistant to iodide 131 treatment. Methods: Thyroid cancer stem cells were firstly isolated as a side population (SP) from human thyroid cancer cell line FTC133. The SP cells from FTC133 were transfected with β-catenin, and then differentiated. The cells were further collected for Western blot, Transwell and MTT assay to investigate the epithelial-mesenchymal transition (EMT) characteristics, tumor growth, invasion, and iodine uptake potency in vitro. Functional NIS expression and iodide uptake in differentiated cells were detected with immunofluorescent staining and iodide uptake assay, respectively. Subcutaneous severe combined immunodeficient (SCID) mice tumor model was induced with differentiated cancer cells to explore the in vivo effect of radioiodine treatment. Further immunohistochemical staining was performed to reveal the changes of functional proteins involved in tumor radioiodine treatment. Results: Side population was isolated from FTC133 accounting for about 0.03%, with high expression of stem cell markers and decreased expression of differentiated cell markers. Western blot showed prominent EMT phenotype in the differentiated cells from β-catenin transfected stem cell model, with absence of epithelial expression of E-cadherin and cytokeratin 18, as well as abnormal expression of vimentin,fibronectin and urokinase-type plasminogen activator. Moreover,compared with cells differentiated from untransfected or empty plasmid transfected stem cells, in vitro proliferation markedly increased 85.4% and 81.0%, respectively (both P<0.01); while in vitro invasion augmented 78.8% and 84.4%, respectively (both P<0.01). Immunofluorescent staining identified that, after transfected with β-catenin, differentiated cells underwent β-catenin nuclear translocation and NIS localization transferred from membrane to plasma, compared with cells from untransfected or empty plasmid transfected stem cells. Cell iodide uptake in vitro decreased about 52.8% and 45.2%, respectively (both P<0.01). Furthermore, in vivo experiment further demonstrated that, cells differentiated from β-catenin transfected stem cells were found with much higher tumor proliferation,tumor growth rate and larger tumor mass after radioiodine 131 treatment (both P<0.05). Conclusion: Induction of β-catenin nuclear translocation in stem cells may generate differentiated thyroid cancer cells that are not sensitive to radioiodine treatment.

[The co-relation of BRAF V600E mutation and factors affecting occurrence and prognosis of papillary thyroid carcinoma]

Objective: To investigate the prevalence of BRAF V600E mutation in thyroid nodules and to analyze the relationship between BRAF V600E mutation and various clinicopathological features. Methods: BRAF V600E mutant gene test was done in 463 cases of thyroid nodules collected from April 2015 to July 2018 in Beijing Hospital. Pathologic sections of 444 cases of papillary thyroid carcinoma were reviewed and clinical information was collected.Statistical analysis of the relationship between BRAF V600E gene mutation and various clinicopathological features was performed with SPSS 21.0 statistical software. Results: There were 109 males and 354 females in the cohort, with a male to female ratio of 1.0∶3.2. The patient ranged in age from 16 to 82 years, with an average age of 46.1 years. The BRAF V600E mutation rates in papillary thyroid carcinoma, benign thyroid nodules and other thyroid carcinoma were 86.5%(384/444),0/15 and 1/4,respectively.There was significant correlation between BRAF V600E mutation and histological diagnosis of papillary thyroid carcinoma (P<0.05). There was no correlation with age, gender, multifocality, bilaterality, coexisting lymphocytic thyroiditis, nodular goiter, maximum diameter, capsule invasion, extrathyroidal extension and clinical stage (P>0.05). Conclusions: BRAF V600E gene mutation is closely related to the occurrence of papillary thyroid carcinoma. BRAF V600E has significant value in the diagnosis of papillary thyroid carcinoma. While BRAF V600E mutation is related to the histological diagnosis, it shows no correlation with other clinicopathologic features. BRAF V600E mutation is not an independent prognostic factor in papillary thyroid carcinoma patients.

[Role of ash2 (absent, small, or homeotic)-like and Jumonji domain-containing protein 3 on histone methylation of interferon-gamma gene and their associations with vascular damage of Kawasaki disease]

Objective: To investigate the impacts of ash2 (absent, small, or homeotic)-like (Ash2L) and Jumonji domain-containing protein 3 (Jmjd3) on histone methylation of interferon-gamma(IFN-γ) gene and association with vascular damage of Kawasaki disease (KD) in acute phase. Methods: This study was performed among 36 children with KD in acute phase (KD group) and 28 age-matched health children (control group), who were treated or underwent physical examination in our hospital between February 2015 and June 2016. Patients were further divided into KD groups with or without coronary artery lesions (KD-CAL(+) , 16 cases; KD-CAL(-), 20 cases). All KD patients were treated with intravenous immunoglobulin. The proportion of type 1 helper T(Th1) cells and protein levels of IFN-γ, T-box expressed in T cells(T-bet), phosphorylated signal transducer and activator of transcription 1(pSTAT1) and phosphorylated signal transducer and activator of transcription 4(pSTAT4) were analyzed by flow cytometry.Chromatin immunoprecipitation was performed to determine histone methylation (histone H3 tri-methyl K4(H3K4me3), histone H3 tri-methyl K27(H3K27me3)) and binding levels of Ash2L, Jmjd3 and Ezh2 associated with IFN-γ in CD4(+) T cells. Quantitative real-time PCR was used to determine mRNA levels of IFN-γ, interferon γ receptor 1(IFN-γR1), interferon γ receptor 2(IFN-γR2), interleukin 12 receptor subunit beta 1(IL-12Rβ1), interleukin 12 receptor subunit beta 2(IL-12Rβ2), interleukin 18 receptor subunit beta α(IL-18Rα), interleukin 18 receptor subunit beta β(IL-18Rβ), tumor necrosis factor receptor 1(TNFR1), toll-like receptor 4(TLR4), receptor interacting serine/threonine kinase 1(RIP-1) and myeloid differentiation primary response gene 88(MyD88) in CD4(+) T cells. Plasma concentrations of IFN-γ, interleukin 12(IL-12), interleukin 18(IL-18) and tumor necrosis factor α(TNF-α) were measured by enzyme-linked Immunosorbent assay. Results: (1)The proportion of Th1 and its protein level of IFN-γ were significantly higher in KD group than those in control group and higher in KD-CAL(+) group than in KD-CAL(-) group (all P<0.05), and lower after treatment than before treatment (all P<0.05). (2)Compared with control group, mRNA level of IFN-γ and IFN-γ-associating H3K4me3 was increased, while level of IFN-γ associating H3K27me3 in CD4(+) T cells was reduced in KD group (all P<0.05), which resulted in a higher rate of H3K4me3/H3K27me3 (P<0.05) in KD group, which was positively correlated with IFN-γ mRNA in KD group(r=0.55, P<0.05). Similar results were found between KD-CAL(+) group and KD-CAL(-) group (all P<0.05). Level of IFN-γ associating H3K27me3 was increased, and mRNA level of IFN-γ and IFN-γ associating H3K4me3 was decreased after treatment than before treatment (all P<0.05). (3)Expression of T-bet protein and binding levels of Ash2L and Jmjd3 with IFN-γ gene were significantly higher in KD group than those in control group(all P<0.05), higher in KD-CAL(+) group than those in KD-CAL(-) group (all P<0.05). These parameters were significantly lower after treatment than before treatment (all P<0.05). Binding level of Ezh2 with IFN-γ gene was similar among various groups (all P>0.05). (4)In comparison with control or after treatment, surface receptors(IFN-γR1/2, IL-12Rβ1/2, IL-18Rα/β, TNFR1 and TLR4) and its downstream molecules(pSTAT1, pSTAT4, RIP(1) and MyD88) in CD4(+) T cells, and plasma concentrations of inflammatory cytokines(IFN-γ, IL-12, IL-18 and TNF-α) were found to be higher in KD group(all P<0.05). These parameters were also higher in KD-CAL(+) group than in KD-CAL(-) group (all P<0.05). Conclusion: Aberrant histone methylation of IFN-γ associating H3K4me3 and H3K27me3 caused by over-binding of Ash2L and Jmjd3 might be involved in immune dysfunction and vascular damage in KD in the acute phase.

An integrative model of prostate cancer interaction with the bone microenvironment

Despite advanced efforts in early diagnosis, aggressive surgical treatment, and use of targeted chemotherapies, the prognosis for many cancers is still dismal. This emphasizes the necessity to develop new strategies for understanding tumor growth and metastasis. Here we use a systems approach that combines mathematical modeling and numerical simulation to develop a predictive computational model for prostate cancer and its subversion of the bone microenvironment. This model simulates metastatic prostate cancer evolution, progressing from normal bone and hormone levels to quantifiable diseased states. The simulations clearly demonstrate phenomena similar to those found clinically in prostate cancer patients. In addition, the major prediction of this model is the existence of low and high osteogenic states that are markedly different from one another. The existence and potential realization of these steady states appear to be mediated by the Wnt signaling pathway and by the effects of PSA on TGF-β, which encourages the bone microenvironment to evolve. The model is used to explore several potential therapeutic strategies, with some potential drug targets showing more promise than others: in particular, completely blocking Wnt and greatly increasing DKK-1 had significant positive effects, while blocking RANKL did not improve the outcome.

Bivalent Histone Codes on WNT5A during Odontogenic Differentiation

Lineage-committed differentiation is an essential biological program during odontogenesis, which is tightly regulated by lineage-specific genes. Some of these genes are modified by colocalization of H3K4me3 and H3K27me3 marks at promoter regions in progenitors. These modifications, named "bivalent domains," maintain genes in a poised state and then resolve for later activation or repression during differentiation. Wnt5a has been reported to promote odontogenic differentiation in dental mesenchyme. However, relatively little is known about the epigenetic modulations on Wnt5a activation during tooth development. Here, we investigated the spatiotemporal patterns of H3K4me3 and H3K27me3 marks in developing mouse molars. Associated H3K4me3 methylases (mixed-lineage leukemia [MLL] complex) and H3K27me3 demethylases (JMJD3 and UTX) were dynamically expressed between early and late bell stage of human tooth germs and in cultured human dental papilla cells (hDPCs) during odontogenic induction. Poised WNT5A gene was marked by bivalent domains containing repressive marks (H3K27me3) and active marks (H3K4me3) on promoters. The bivalent domains tended to resolve during inducted differentiation, with removal of the H3K27me3 mark in a JMJD3-dependent manner. When JMJD3 was knocked down in cultured hDPCs, odontogenic differentiation was suppressed. The depletion of JMJD3 epigenetically repressed WNT5A activation by increased H3K27me3 marks. In addition, JMJD3 could physically interact with ASH2L, a component of the MLL complex, to form a coactivator complex, cooperatively modulating H3K4me3 marks on WNT5A promoters. Overall, our study reveals that transcription activities of WNT5A were epigenetically regulated by the negotiated balance between H3K27me3 and H3K4me3 marks and tightly mediated by JMJD3 and MLL coactivator complex, ultimately modulating odontogenic commitment during dental mesenchymal cell differentiation.

[Anatomic study and clinical practice of mesopancreas and total mesopancreatic excision]

Objective: To explore the anatomical characteristics of the mesopancreas, to define the range of the total mesopancreas excision and to evaluate the feasibility, safety and effectiveness in the treatment of pancreatic cancer. Methods: A regional anatomical and pathological study was performed on 14 cadavers with large slices and paraffin sections. The clinical and pathological data of 58 consecutive patients underwent total mesopancreas excision for pancreatic head carcinoma from January 2013 to December 2015 were prospectively collected and analysed. The perioperative morbidity, mortality and clinical outcomes of patients underwent total mesopancreas excision were compared with the patients underwent conventional pancreaticoduodenectomy from January 2010 to December 2012. Results: The mesopancreas located in the retropancreatic area, extending from the head, neck, and uncinated process of pancreas to the aorto-caval groove, in which there were loose areolar tissue, adipose tissue, nerve plexus, lymphatic and capillaries. Although no fibrous sheath or fascia like mesocolorectum was found around the structures, a relatively fixed extent could be defined according to its embryologic and anatomic characters. In clinical practice, total mesopancreas excision was classified into two levels according to the extent of resection in this series: level Ⅰ was a"standard total mesopancreas excision" or"total mesopancreas excision in a narrow sense" , which was similar to the extent of standard resection from consensus statement of ISGPS. Level Ⅱ was defined as any procedure extending the range of level Ⅰ, called the"extended total mesopancreas excision" or"total mesopancreas excision in a broad sense". In TMpE group, the intraoperative blood loss( (461.4±184.5)ml vs. (532.2±319.8)ml, P=0.301), operation time( (368.6±92.5)minutes vs. (397.1±112.7)minutes, P=0.559), total complication rate (39.7% vs. 51.2%, P=0.250), fistula mortality (25.9% vs. 30.2%, P=0.628) were all reduced. There were significantly higher R0 rate (91.4% vs.76.7%, P=0.041) and more harvested lymph nodes (16.2 vs. 11.4, P=0.000) and lower total and local recurrence: rate (half-year local recurrence rate: 7.8% vs. 23.7%, P=0.036; one-year local recurrence rate: 18.2% vs. 39.5%, P=0.018) and longer disease-free survival (16.9 months vs. 13.4 months, P=0.044) and overall survival(22.5 months vs. 19.9 months, P>0.05) were also found in the study group. Conclusions: Mesopancreas is different from mesorectum since it has no fascial envelop, which should be regarded as a surgical concept, rather than an anatomical structure. Total mesopancreas excision is safe and feasible for pancreatic head cancer and probably helps to increase the R0 resection rate and improve the clinical outcomes.

Cloacogenic adenocarcinoma of the vulva: one new case and literature review

Primary adenocarcinoma of the vulva is uncommon, and cloacogenic adenocarcinoma of the vulva is extremely rare. Here the authors report a vulvar neoplasm, arising in continuity with the epidermis, characterized by villoglandular architecture, and mucinous-type ep- ithelium with intestinal differentiation (goblet cells). Histochemistry, immunohistochemistry, and gene mutation analysis revealed a colon-like pattern, except for CK7 expression. Extensive workup failed to reveal other primary cancers. In order to provide a much bet- ter experience for diagnosis, the authors compared the previously published cases with the present case regarding clinical presentation and histopathologic aspect. They believe that the notion of the tumor arising from cloacal remnants is a more acceptable viewpoint, and its behavior is mostly indolent. In the present case, a wide local excision was sufficient for radical cure.

Selective binding in different adsorption sites of a 2D covalent organic framework

Monolayer covalent organic frameworks selectively bind fullerenes and trichlorobenzene at different sites via different types of interactions.

Effects of LeY glycan expression on embryo implantation

OBJECTIVE

To investigate the correlation between LeY glycan expression and embryo implantation.

MATERIALS AND METHODS

Uterine epithelial cells before implantation were transfected with FUT1siRNA to inhibit FUT1 (the gene encoding the key enzyme of LeY synthesis) expression and treated with 10 ng/ml leukemia inhibitory factor (LIF). Murine embryo implantation model in vitro was prepared by late blastocysts with identical morphology and treated uterine epithelial cells co-culture. Using RT-PCR, dot blot and observation of embryo attachment to analyze FUT1 gene expression and LeY synthesis of uterine epithelial cells and studied further the correlation of LeY expression level and embryo implantation.

RESULTS

FUT1 gene expression and LeY synthesis declined after cells were transfected with FUT1siRNA, and LIF promoted FUT1 expression and LeY synthesis. After expression of FUT1 gene was inhibited, attachment rate of embryos lowered, but LIF up-regulated FUT1 expression and increased the attachment rate of embryos.

CONCLUSIONS

These results indicated regulating FUT1 expression affected LeY synthesis, and then LeY regulated the recognition and attachment of uterus-embryo and participates in embryo implantation further.

Transcriptional activity of acetylcholinesterase gene is regulated by DNA methylation during C2C12 myogenesis

The expression of acetylcholinesterase (AChE), an enzyme hydrolyzes neurotransmitter acetylcholine at vertebrate neuromuscular junction, is regulated during myogenesis, indicating the significance of muscle intrinsic factors in controlling the enzyme expression. DNA methylation is essential for temporal control of myogenic gene expression during myogenesis; however, its role in AChE regulation is not known. The promoter of vertebrate ACHE gene carries highly conserved CG-rich regions, implying its likeliness to be methylated for epigenetic regulation. A DNA methyltransferase inhibitor, 5-azacytidine (5-Aza), was applied onto C2C12 cells throughout the myotube formation. When DNA methylation was inhibited, the promoter activity, transcript expression and enzymatic activity of AChE were markedly increased after day 3 of differentiation, which indicated the putative role of DNA methylation. By bisulfite pyrosequencing, the overall methylation rate was found to peak at day 3 during C2C12 cell differentiation; a SP1 site located at -1826bp upstream of mouse ACHE gene was revealed to be heavily methylated. The involvement of transcriptional factor SP1 in epigenetic regulation of AChE was illustrated here: (i) the SP1-driven transcriptional activity was increased in 5-Aza-treated C2C12 culture; (ii) the binding of SP1 onto the SP1 site of ACHE gene was fully blocked by the DNA methylation; and (iii) the sequence flanking SP1 sites of ACHE gene was precipitated by chromatin immuno-precipitation assay. The findings suggested the role of DNA methylation on AChE transcriptional regulation and provided insight in elucidating the DNA methylation-mediated regulatory mechanism on AChE expression during muscle differentiation.

In vitro and in vivo characterisation of the metabolism and disposition of suvorexant in humans

1. Suvorexant (MK-4305, Belsomra®) is a first-in-class dual orexin receptor antagonist approved in the USA and Japan for the treatment of insomnia. The current studies describe suvorexant's absorption, disposition and potential for CYP-mediated drug interactions in humans. 2. Following single oral administration of [(14)C]suvorexant to healthy human subjects, 90% of the radioactivity was recovered (66% in faeces, 23% in urine), primarily as oxidative metabolites. 3. In plasma, suvorexant and M9 were predominant, accounting for 30 and 37% of the total radioactivity, respectively. Metabolite M17 became more prominent (approaching 10%) following multiple daily doses of unlabelled suvorexant. M9 and M17 are not expected to contribute to the pharmacological activity of suvorexant due to reduced orexin receptor binding affinity and limited brain penetration. 4. CYP3A was determined to be the predominant enzyme mediating suvorexant oxidation. In vitro, suvorexant demonstrated reversible inhibition of CYP3A4 and 2C19 (IC50 ∼ 4-5 μM), and weak time-dependent inhibition of CYP3A4 (KI = 12 μM, kinact = 0.14 min(-1)). Suvorexant was also a weak inducer of CYP3A4, 1A2 and 2B6. Given the low plasma concentrations at clinical doses, suvorexant was not anticipated to cause significant drug interactions via inhibition and/or induction of major CYPs in vivo.

The Identification of Two Head Smut Resistance-Related QTL in Maize by the Joint Approach of Linkage Mapping and Association Analysis

Head smut, caused by the fungus Sphacelotheca reiliana (Kühn) Clint, is a devastating threat to maize production. In this study, QTL mapping of head smut resistance was performed using a recombinant inbred line (RIL) population from a cross between a resistant line "QI319" and a susceptible line "Huangzaosi" (HZS) with a genetic map constructed from genotyping-by-sequencing (GBS) data and composed of 1638 bin markers. Two head smut resistance QTL were identified, located on Chromosome 2 (q2.09HR) and Chromosome 5 (q5.03HR), q2.09HR is co-localized with a previously reported QTL for head smut resistance, and the effect of q5.03HR has been validated in backcross populations. It was also observed that pyramiding the resistant alleles of both QTL enhanced the level of resistance to head smut. A genome-wide association study (GWAS) using 277 diverse inbred lines was processed to validate the mapped QTL and to identify additional head smut resistance associations. A total of 58 associated SNPs were detected, which were distributed in 31 independent regions. SNPs with significant association to head smut resistance were detected within the q2.09HR and q5.03HR regions, confirming the linkage mapping results. It was also observed that both additive and epistastic effects determine the genetic architecture of head smut resistance in maize. As shown in this study, the combined strategy of linkage mapping and association analysis is a powerful approach in QTL dissection for disease resistance in maize.

Hepatitis B virus stimulates G6PD expression through HBx-mediated Nrf2 activation

Metabolic reprogramming is a hallmark of physiological changes in cancer. Cancer cells primarily apply glycolysis for cell metabolism, which enables the cells to use glycolytic intermediates for macromolecular biosynthesis in order to meet the needs of cell proliferation. Here, we show that glucose-6-phosphate dehydrogenase (G6PD), the first and rate-limiting enzyme of the pentose phosphate pathway, is highly expressed in chronic hepatitis B virus (HBV)-infected human liver and HBV-associated liver cancer, together with an elevated activity of the transcription factor Nrf2. In hepatocytes, HBV stimulates by its X protein (HBx) the expression of G6PD in an Nrf2 activation-dependent pathway. HBx associates with the UBA and PB1 domains of the adaptor protein p62 and augments the interaction between p62 and the Nrf2 repressor Keap1 to form HBx–p62–Keap1 complex in the cytoplasm. The aggregation of HBx–p62–Keap1 complexes hijacks Keap1 from Nrf2 leading to the activation of Nrf2 and consequently G6PD transcription. Our data suggest that HBV upregulates G6PD expression by HBx-mediated activation of Nrf2. This implies a potential effect of HBV on the reprogramming of the glucose metabolism in hepatocytes, which may be of importance in the development of HBV-associated hepatocarcinoma.

The effect of treadmill training and N-acetyl-l-cysteine intervention on biogenesis of cytochrome c oxidase (COX)

Mitochondrial biogenesis refers to increased content of mitochondria, which has been shown to be promoted by aerobic exercise. During this process, oxidative stress is considered the essential initiator. Even though some studies have addressed the issue as to whether antioxidants would hamper the effects of exercise on mitochondrial biogenesis, no consensus has been achieved. Therefore, the purpose of the present study was to investigate the effects of exercise and antioxidant intervention on mitochondrial biogenesis, as well as COX biogenesis. Thirty-two clean-grade male ICR mice were randomly assigned to a control group (Con), exercise group (Ex), N-acetyl-l-cysteine group (NAC), or NAC plus exercise group (NEx). The NAC and NEx groups were injected with NAC (0.1 mg/g/2 days) intraperitoneally for 3 weeks, whereas the Con and Ex groups were administered saline for the same period of time. Mice assigned to Ex and NEx groups started exercise training 1 week before drug intervention was initiated. After 1 week of acclimatization, the mice were allowed to run at a speed of 28 m/min for 60 min, 6 days a week. The results showed that exercise training caused an increase in mRNA and protein levels of COXIV, whereas NAC intervention lowered the two so significantly that even exercise training could not reverse the effect of NAC intervention. Our data suggest that even though antioxidant intervention could alleviate oxidative damage caused by exercise, it was not necessarily beneficial for mitochondrial biogenesis.