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Comorbidity exists between metabolic disorders and depressive syndrome with unclear mechanisms. To characterize the causal relationship, we adopted a 12-week high-fat diet (HFD) to induce metabolic disorder and depressive phenotypes in mice. Initially, we identified an enhanced glutamatergic input in the nucleus accumbens of HFD mice. Retrograde tracing and chemogenetic inhibition showed that the hyperactive ventral hippocampal glutamatergic afferents to the nucleus accumbens determined the exhibition of depression-like behavior in HFD mice. Using lentiviral knockdown and overexpression approaches, we proved that HFD-induced downregulation of glial glutamate transporters, GLAST and GLT-1, contributed to the observed circuit maladaptations and subsequent depression-like behaviors. Finally, we identified a potential therapeutic agent, riluzole, which could mitigate the HFD-induced behavioral deficits by normalizing the expressions of GLAST and GLT-1 and ventral hippocampal glutamatergic afferents to the nucleus accumbens. Overall, astrocyte-mediated disturbance in glutamatergic transmission underlies the metabolic disorder-related depressive syndrome and represents a therapeutic target for this subtype of depressive mood disorders.

Metastasis is the main cause of death in many cancers including colorectal cancer (CRC); however, the underlying mechanisms responsible for metastatic progression remain largely unknown. We found that nuclear TYRO3 receptor tyrosine kinase is a strong predictor of poor overall survival in patients with CRC. The metastasis-promoting function of nuclear TYRO3 requires its kinase activity and matrix metalloproteinase–2 (MMP-2)–mediated cleavage but is independent of ligand binding. Using proteomic analysis, we identified bromodomain-containing protein 3 (BRD3), an acetyl-lysine reading epigenetic regulator, as one of nuclear TYRO3’s substrates. Chromatin immunoprecipitation-sequencing data reveal that TYRO3-phosphorylated BRD3 regulates genes involved in anti-apoptosis and epithelial-mesenchymal transition. Inhibition of MMP-2 or BRD3 activity by selective inhibitors abrogates nuclear TYRO3-induced drug resistance and metastasis in organoid culture and in orthotopic mouse models. These data demonstrate that MMP-2/TYRO3/BRD3 axis promotes the metastasis of CRC, and blocking this signaling cascade is a promising approach to ameliorate CRC malignancy.

Open inquiry learning and student–scientist partnerships are two effective ways of enhancing students’ science learning; however, due to their challenging and intimidating nature, students might encounter emotional breakdowns when engaging with them. To address communicative and emotional issues in high school students’ internships with scientists, this ethnographic case study integrated a pedagogical tool called cogenerative dialogues (cogen), which are conversations cogenerated by different stakeholders to reflect on participants’ experiences and help them reach collective decisions about the rules, roles, and responsibilities that govern their partnerships. Data sources include video recordings of internship activities, video recordings of cogenerative dialogues, students’ journals and interviews, and researchers’ field notes, pictures, and artifacts collected during the internship. Drawing on the emotion regulation framework, I demonstrate how cogen could be used as a powerful tool to reveal emotion suppression, share emotion regulation strategies, and transform negative emotions into positive emotions. The results of this case study show that cogen played an important role in addressing specific issues one at a time and sustaining student engagement throughout the internship program. The implications of cogen for sustainability and organizational health are discussed.

This paper evaluates the use of plasma etching for preparing TEM specimens to analyze high aspect ratio 3D NAND integrated circuits. By controlling plasma etching parameters, a relatively high material removal rate could be obtained. Moreover, through the control of etch time, the top region of the test specimens could be completely removed down through the expected number of layers, making it possible to resolve details throughout the entire sample, particularly in the middle region of the 3D NAND, using TEM cross-section analysis.

Scaffold hopping-driven lead optimizations were performed based on our prior lead 7-methoxy-4-(2-methylquinazolin-4-yl)-3,4-dihydroquinoxalin-2(1H)-one (2a) by C-ring expansion and isometric replacement of the A/B-ring, successively, aimed at finding new potential alternative drug candidates with different scaffold(s), high antitumor activity, and other improved properties to replace prior, once promising drug candidates that failed in further studies. Two series of new compounds 7 (a-d) and 13 (a-j) were synthesized and evaluated for antitumor activity, leading to the discovery of three highly potent compounds 13c, 13d, and 13e with different scaffolds. They exhibited similar high antitumor activity with single digital low nanomolar GI50 values (4.6-9.6 nM) in cellular assays, comparable to lead 2a, clinical drug candidate CA-4, and paclitaxel in the same assays. Further biological evaluations identified new active compounds as tubulin polymerization inhibitors targeting the colchicine binding site. Moreover, 13d showed better aqueous solubility than 2a and a similar log P value.

Betulinic acid (BA), a pentacyclic triterpenoid, exhibits broad spectrum antiproliferative activity, but generally with only modest potency. To improve BA’s pharmacological properties, fluorine was introduced as a single atom at C-2, creating two diastereomers, or in a trifluoromethyl group at C-3. We evaluated the impact of these groups on antiproliferative activity against five human tumor cell lines. A racemic 2-F-BA (compound 6) showed significantly improved antiproliferative activity, while each diastereomer exhibited similar effects. We also demonstrated that 2-F-BA is a topoisomerase (Topo) I and IIα dual inhibitor in cell-based and cell-free assays. A hypothetical mode of binding to the Topo I-DNA suggested a difference between the hydrogen bonding of BA and 2-F-BA to DNA, which may account for the difference in bioactivity against Topo I.

Endometriosis is a highly prevalent gynecological disease with severe negative impacts on life quality and financial burden. Unfortunately, there is no cure for this disease, which highlights the need for further investigation about the pathophysiology of this disease to provide clues for developing novel therapeutic regimens. Herein, we identified that vascular endothelial growth factor (VEGF)-C, a potent lymphangiogenic factor, is up-regulated in endometriotic cells and contributes to increased lymphangiogenesis. Bioinformatic analysis and molecular biological characterization revealed that VEGF-C is negatively regulated by an orphan nuclear receptor, chicken ovalbumin upstream promoter-transcription factor II (COUP-TFII). Further studies demonstrated that proinflammatory cytokines, via suppression of COUP-TFII level, induce VEGF-C overexpression. More importantly, we show that functional VEGF-C is transported by extracellular vesicles (EVs) to enhance the lymphangiogenic ability of lymphatic endothelial cells. Autotransplanted mouse model of endometriosis showed lenvatinib treatment abrogated the increased lymphatic vessels development in the endometriotic lesion, enlarged retroperitoneal lymph nodes, and immune cells infiltration, indicating that blocking VEGF-C signaling can reduce local chronic inflammation and concomitantly endometriosis development. Evaluation of EV-transmitted VEGF-C from patients' sera demonstrates it is a reliable noninvasive way for clinical diagnosis. Taken together, we identify the vicious cycle of inflammation, COUP-TFII, VEGF-C, and lymphangiogenesis in the endometriotic microenvironment, which opens up new horizons in understanding the pathophysiology of endometriosis. VEGF-C not only can serve as a diagnostic biomarker but also a molecular target for developing therapeutic regimens.

Research is urgently needed to learn how to improve the emotional climate of science learning by ameliorating excesses of negative emotions, which may lead to students dropping out of school, teachers burning out, and health problems for both groups. This is especially true when teachers and students are situated in highly challenging environments such as project-based learning (PBL) practice. PBL is regarded as an effective way to engage students meaningfully in science learning. However, emotional dissonance between teachers and students can arise because of many challenges in PBL (e.g., difficulty of assessing learning, uncertainty about teacher and student roles). In this study, we investigated how cogenerative dialogues (cogens) served as a pedagogical tool to address emotional issues in a PBL science internship. Data sources included 210 h of video-recorded internship and cogen sessions conducted with one laboratory team. Drawing on polyvagal theory and event-oriented inquiry, this case study shows how educators used cogens as a tool to transform the emotional climate in an internship through respectful communication emphasizing equality, thereby increasing reciprocity, equality, and synchronicity among teachers and students. The findings may help students and teachers regulate their expressions of emotion and enhance the quality of classroom interactions and learning environments.

TYRO3 belongs to the TAM (TYRO3, AXL, and MER) receptor family, a unique subfamily of the receptor tyrosine kinases. Members of TAM family share the same ligand, growth arrest-specific 6, and protein S. Although the signal transduction pathways of TYRO3 have not been evaluated in detail, overexpression and activation of TYRO3 receptor tyrosine kinase have been reported to promote cell proliferation, survival, tumorigenesis, migration, invasion, epithelial-mesenchymal transition, or chemoresistance in several human cancers. Targeting TYRO3 could break the kinase signaling, stimulate antitumor immunity, reduce tumor cell survival, and regain drug sensitivity. To date, there is no specific TYRO3-targeted drug, the effectiveness of targeting TYRO3 in cancer is worthy of further investigations. In this review, we present an update on molecular biology of TYRO3, summarize the development of potential inhibitors of TAM family members, and provide new insights in TYRO3-targeted treatment.Impact statementCancer is among the leading causes of death worldwide. In 2016, 8.9 million people are estimated to have died from various forms of cancer. The current treatments, including surgery with chemotherapy and/or radiation therapy, are not effective enough to provide full protection from cancer, which highlights the need for developing novel therapy strategies. In this review, we summarize the molecular biology of a unique member of a subfamily of receptor tyrosine kinase, TYRO3 and discuss the new insights in TYRO3-targeted treatment for cancer therapy.

Rationale: Endometriosis is a highly prevalent gynecological disease in women of reproductive age that markedly reduces life quality and fertility. Unfortunately, there is no cure for this disease, which highlights that more efforts are needed to investigate the underlying mechanism for designing novel therapeutic regimens. This study aims to investigate druggable membrane receptors distinctively expressed in endometriotic cells. Methods: Bioinformatic analysis of public databases was employed to identify potential druggable candidates. Normal endometrial tissues and ectopic endometriotic lesions were obtained for the determination of target genes. Primary endometrial and endometriotic stromal cells as well as two different mouse models of endometriosis were used to characterize molecular mechanisms and therapeutic outcomes of endometriosis, respectively. Results: Anthrax toxin receptor 2 (ANTXR2) mRNA and protein are upregulated in the endometriotic specimens. Elevation of ANTXR2 promotes endometriotic cell adhesion, proliferation, and angiogenesis. Furthermore, hypoxia is the driving force for ANTXR2 upregulation via altering histone modification of ANTXR2 promoter by reducing the repressive mark, histone H3 lysine 27 (H3K27) trimethylation, and increasing the active mark, H3K4 trimethylation. Activation of ANTXR2 signaling leads to increased Yes-associated protein 1 (YAP1) nuclear translocation and transcriptional activity, which contributes to numerous pathological processes of endometriosis. Pharmacological blocking of ANTXR2 signaling not only prevents endometriotic lesion development but also causes the regression of established lesion. Conclusion: Taken together, we have identified a novel target that contributes to the disease pathogenesis of endometriosis and provided a potential therapeutic regimen to treat it.

Science internships where students work with scientists have been suggested to have many positive impacts on students’ science learning. However, little research has been conducted to investigate t...

Working with scientists has been suggested as an effective way for high school students to learn science more authentically. However, several challenges hinder partnerships between students and scientists, such as intimidation issues, the complexity of scientific language, and communication barriers. The purpose of this phenomenographic study was to introduce a pedagogical tool, cogenerative dialogs (cogens), to improve student–scientist partnerships and to investigate high school students’ experience of cogens with scientists. The analysis of high school students’ and scientists’ experiences of cogens in this study suggested four positive and two challenging experiences that shed light on the use of cogens by two distinctly different groups of stakeholders. This study demonstrates positive evidence that cogens can help students build a stronger bond with scientists to enhance their science learning. Suggestions to improve cogen practices between students and scientists are provided.

The strong hemolytic toxicity of pulsatilla saponin D (1, HD(50) 6.3 μM) has hampered its clinical development as an injectable anticancer agent. To combat this challenge, 17 new derivatives of 1 with ring C, C-28, or C-3 modifications were synthesized and evaluated for cytotoxicity against several selected human tumor lines, as well as for hemolytic toxicity against rabbit erythrocytes. Structure−activity relationship (SAR) and structure−toxicity relationship (STR) correlations were also elucidated. Compared to the lead compound 1, the hemolytic activity of all 17 derivatives dropped dramatically. Notably, compound 14 exhibited significant cytotoxicity toward A549 human lung cancer cells (IC(50) 2.8 μM) in a dose-dependent manner without hemolytic toxicity (HD(50) > 500 μM). Molecular studies indicated that 14 induced typical G(1) cell cycle arrest and apoptosis in A549 cells, and Western blot assays suggested that both intrinsic and extrinsic apoptosis pathways were activated by 14. Collectively, compound 14 may merit further development as a potential anti-lung cancer agent.

Working with scientists has been suggested as an effective way for high-school students to learn authentic science. However, little research has involved students’ perceptions of science learning environments in a university internship. This study drew on the theoretical framework of community of practice with cogenerative dialogues to design an internship program that aims to build a constructivist internship for students. Students who learned science in the internship program developed stronger constructivist learning perceptions than those who learned science in school. Specifically, students perceived that they had more opportunities to think independently of the instructors and other students. Three effective principles for program design are: (a) high school students conduct open-inquiry projects with the support of scientists; (b) high school students and scientists conduct cogenerative dialogues regularly to address issues and share experiences; and (c) high school students present their project proposals and scientific findings at open house events. Implications of the results are discussed.

Research in science education has shown that one’s identities as science learner and teacher can mediate their pedagogical practices.Grounded in the perspec-tive that language is a resource for identity (re)construction (Gee, 2000), the present study sought to understand how preservice science teachers’ identities were manifested in their philosophies of science learning and teaching. Drawing on identity theory, we analyzed 76 essays (38 preservice teachers’sci-ence learning autobiographies and teaching philosophies) in terms of four dimensions of identity: nature, institution, discourse, and affinity. Our findings suggest that affinity identity plays an important role in shaping participants’ science learning experiences and teaching philosophy. Ways to enhance preservice teachers’ identities as science teachers and the relevance of adopting a discursive analytical approach to identity as a means of improving science teacher education programs are discussed.

7-Methoxy-4-(2-methylquinazolin-4-yl)-3,4-dihydroquinoxalin-2(1H)-one (2), a promising anticancer lead previously identified by us, inhibited tumor growth by 62% in mice at 1.0 mg/kg without obvious signs of toxicity. Moreover, compound 2 exhibited extremely high antiproliferative activity in the NIH-NCI 60 human tumor cell line panel, with low to subnanomolar GI(50) values (10(−10) M level). It also showed a suitable balance between aqueous solubility and lipophilicity, as well as moderate metabolic stability in vivo. Mechanistic studies using Mayer’s hematoxylin and eosin and immunohistochemistry protocols on xenograft tumor tissues showed that 2 inhibited tumor cell proliferation, induced apoptosis, and disrupted tumor vasculature. Moreover, evaluation of new synthetic analogues (6a−6t) of 2 indicated that appropriate 2-substitution on the quinazoline ring could enhance antitumor activity and improve druglike properties. Compound 2 and its analogues with a 4-(2-methylquinazolin-4-yl)-3,4-dihydroquinoxalin-2(1H)-one scaffold thus represent a novel class of tubulin-binding tumor-vascular disrupting agents (tumor-VDAs) that target established blood vessels in tumors.

Early dissemination is a unique characteristic and a detrimental process of pancreatic ductal adenocarcinoma (PDAC); however, the underlying mechanism remains largely unknown. Here, we investigate the role of dual-specificity phosphatase-2 (DUSP2)-vascular endothelial growth factor-C (VEGF-C) axis in mediating PDAC lymphangiogenesis and lymphovascular invasion. Expression of DUSP2 is greatly suppressed in PDAC, which results in increased aberrant expression of extracellular vesicle (EV)-associated VEGF-C secretion. EV-VEGF-C exerts paracrine effects on lymphatic endothelial cells and autocrine effects on cancer cells, resulting in the lymphovascular invasion of cancer cells. Tissue-specific knockout of Dusp2 in mouse pancreas recapitulates PDAC phenotype and lymphovascular invasion. Mechanistically, loss-of-DUSP2 enhances proprotein convertase activity and vesicle trafficking to promote the release of the mature form of EV-VEGF-C. Collectively, these findings represent a conceptual advance in understanding pancreatic cancer lymphovascular invasion and suggest that loss-of-DUSP2-mediated VEGF-C processing may play important roles in early dissemination of pancreatic cancer. Abbreviations: DUSP2: dual-specificity phosphatase-2; VEGF-C: vascular endothelial growth factor-C; EV: extracellular vesicles; PDAC: pancreatic ductal adenocarcinoma; KD: knockdown