Andrographolide inhibits the activation of spinal microglia and ameliorates mechanical allodynia

Andrographolide (Andro), a labdane diterpene, possesses anti-inflammatory properties and has been used to treat numerous inflammatory diseases. Novel findings revealed that Andro might be vital in regulating pain. However, the contribution of Andro to chronic inflammatory pain has yet to be determined, and its underlying mechanism of action remains unknown. In this study, we observed that Andro attenuated mechanical allodynia in inflammatory pain mice induced by injecting complete Freund's adjuvant (CFA) into the right hind paws. This analgesic effect of Andro is mainly dependent on its inhibition of microglial overactivation and the release of proinflammatory cytokines (TNF and IL-1β) in lumbar spinal cords of inflammatory pain model mice. More importantly, our data in vivo and in vitro revealed a negative role for Andro in regulating the TLR4/NF-κB signaling pathway, which might contribute to the inhibition of spinal microglial activation and proinflammatory cytokines production, and the improvement of paw withdrawal thresholds in a mouse model of chronic inflammatory pain evoked by CFA. We further found the potential interaction of Andro with TLR4/myeloid differentiation factor 2 heterodimer using molecular modeling, implying that TLR4 might be a potential target for Andro to exert an analgesic effect. Taken together, our findings demonstrated that the modulation of spinal microglial activation by Andro might be substantially conducive to managing chronic pain triggered by neuroinflammation.

Neuroprotection and Mechanism of Gas-miR36-5p from Gastrodia elata in an Alzheimer's Disease Model by Regulating Glycogen Synthase Kinase-3β

Alzheimer's disease (AD) is currently the most common neurodegenerative disease. Glycogen synthase kinase 3β (GSK-3β) is a pivotal factor in AD pathogenesis. Recent research has demonstrated that plant miRNAs exert cross-kingdom regulation on the target genes in animals. Gastrodia elata (G. elata) is a valuable traditional Chinese medicine that has significant pharmacological activity against diseases of the central nervous system (CNS). Our previous studies have indicated that G. elata-specific miRNA plays a cross-kingdom regulatory role for the NF-κB signaling pathway in mice. In this study, further bioinformatics analysis suggested that Gas-miR36-5p targets GSK-3β. Through western blot, RT-qPCR, and assessments of T-AOC, SOD, and MDA levels, Gas-miR36-5p demonstrated its neuroprotective effects in an AD cell model. Furthermore, Gas-miR36-5p was detected in the murine brain tissues. The results of the Morris water maze test and western blot analysis provided positive evidence for reversing the learning deficits and hyperphosphorylation of Tau in AD mice, elucidating significant neuroprotective effects in an AD model following G. elata RNA administration. Our research emphasizes Gas-miR36-5p as a novel G. elata-specific miRNA with neuroprotective properties in Alzheimer's disease by targeting GSK-3β. Consequently, our findings provide valuable insights into the cross-kingdom regulatory mechanisms underlying G. elata-specific miRNA, presenting a novel perspective for the treatment of Alzheimer's disease.

Association of maternal age with adverse pregnancy outcomes: A prospective multicenter cohort study in China

Background

Although maternal age might affect pregnancy outcomes, it remains unclear whether this relationship is linear or curvilinear and if it differs between nulliparous and multiparous women. We aimed to characterize the relationship between maternal age and risks of pregnancy outcomes in a diverse sample of Chinese singleton pregnant women and to evaluate whether the relationship varied by parity.

Methods

We based this prospective multicenter cohort study on data from 18 495 singleton pregnant women who participated in the University Hospital Advanced Age Pregnant Cohort Study, conducted in eight Chinese public hospitals from 2016 to 2021. We used restricted cubic splines to model nonlinear relationships between maternal age continuum and adverse outcomes, and performed multivariable log-binomial regression to estimate the adjusted relative risk (RR) and 95% confidence interval (CI).

Results

Among 18 495 singleton pregnant women (mean age 35.7, standard deviation (SD) = 4.2 years), maternal age was not related to postpartum hemorrhage or small for gestational age, but showed a positive, nonlinear relationship to gestational diabetes mellitus, hypertensive disorders of pregnancy, preeclampsia, placenta accreta spectrum, placenta previa, cesarean delivery, preterm birth, large for gestational age, macrosomia, and fetal congenital anomaly, with inflection points around 35.6-40.4 years. Compared to women younger than 35 years, older women had higher risks of adverse pregnancy outcomes, except for postpartum hemorrhage and small for gestational age. The risks of placenta accreta spectrum, placenta previa, large for gestational age, and macrosomia were highest for women aged 40-44 years, and risks of gestational diabetes mellitus, hypertensive disorders of pregnancy, preeclampsia, cesarean delivery, preterm birth and congenital anomaly were highest for those aged ≥45 years. Most risks were more pronounced in nulliparous than multiparous women (P for interaction <0.02).

Conclusions

Delayed childbirth was related to increased risks of adverse pregnancy outcomes, especially for nulliparous women. Appropriate childbearing age, generally before 35 years, is recommended for optimising pregnancy outcomes.

Gastrodia elata specific miRNA attenuates neuroinflammation via modulating NF-κB signaling pathway

AIMS

Based on our previous research on the specific miRNAs identified from Gastrodia elata, we selected Gas-miR2-3p to investigate its effects on neuroinflammation via in vitro and in vivo experiments.

RESULTS

RT-qPCR analysis indicated that G. elata specific Gas-miR2-3p was detected in all murine tissues post-oral administration, suggesting their potential as orally bioavailable miRNA. The analysis of RT-qPCR, Western blotting and ELISA assays consistently demonstrate that the expression of inflammatory factors as TNF-α, IL-6, IL-1β was decreased and the expression levels of p-p65 and p-IκBα were downregulated after the action of Gas-miR2-3p in both cell and animal experiments.

CONCLUSION

Gas-miR2-3p can attenuate neuroinflammation by regulating the inflammation factors and suppressing the activation of the NF-κB signaling pathway. Our findings indicate that G. elata miRNAs, as novel active components, perform a modulatory role in the NF-κB signaling pathway associated with neuroinflammation in a cross-species way.

The acetyltransferase BmCBP changes the acetylation modification of BmSP3 and affects its protein expression in silkworm, Bombyx mori

BACKGROUND

Protein acetylation is an important post-translational modification (PTM) that widely exists in organisms. As a reversible PTM, acetylation modification can regulate the function of proteins with high efficiency. In the previous study, the acetylation sites of silkworm proteins were identified on a large scale by nano-HPLC/MS/MS (nanoscale high performance liquid chromatography-tandem secondary mass spectrometry), and a total of 11 acetylation sites were discovered on Bombyx mori nutrient-storage protein SP3 (BmSP3). The purpose of this study was to investigate the effect of acetylation level on BmSP3.

METHODS AND RESULTS

In this study, the acetylation of BmSP3 was further verified by immunoprecipitation (IP) and Western blotting. Then, it was confirmed that acetylation could up-regulate the expression of BmSP3 by improving its protein stability in BmN cells. Co-IP and RNAi experiments showed acetyltransferase BmCBP could bind to BmSP3 and catalyze its acetylation modification, then regulate the expression of BmSP3. Furthermore, the knock-down of BmCBP could improve the ubiquitination level of BmSP3. Both acetylation and ubiquitination occur on the side chain of lysine residues, therefore, we speculated that the acetylation of BmSP3 catalyzed by BmCBP could competitively inhibit its ubiquitination modification and improve its protein stability by inhibiting ubiquitin-mediated proteasome degradation pathway, and thereby increase the expression and intracellular accumulation.

CONCLUSIONS

BmCBP catalyzes the acetylation of BmSP3 and may improve the stability of BmSP3 by competitive ubiquitination. This conclusion provides a new functional basis for the extensive involvement of acetylation in the regulation of nutrient storage and utilization in silkworm, Bombyx mori.

Corrigendum: Involvement of PtPHR1 in phosphates starvation-induced alkaloid biosynthesis in Pinellia ternata (Thunb.) Breit

[This corrects the article DOI: 10.3389/fpls.2022.914648.].

Gestational Vitamin E Status and Gestational Diabetes Mellitus: A Retrospective Cohort Study

Objectives: To examine the association between vitamin E (VE) status and gestational diabetes mellitus (GDM). Methods: A retrospective cohort study was conducted by using data of 52,791 women at 137 hospitals across 22 provinces of China. A fasting plasma glucose (FPG) level of ≥5.1 mmol/L between the 24th and 40th weeks of gestation was used as the criteria for the diagnosis of GDM. Mean FPG level and GDM rate were calculated within each combination of the first-trimester VE concentration categories and gestational change categories. The associations of the first-trimester VE concentrations and gestational VE change with FPG and GDM were examined by employing generalized additive models (GAMs). Results: 7162 (13.57%) cases were diagnosed with GDM. The GDM rate was 22.44%, 11.50%, 13.41%, 12.87%, 13.17%, 13.44%, 12.64%, and 14.24% among women with the first-trimester VE concentrations of <7.2, 7.2–7.9, 8.0–9.3, 9.4–11.0, 11.1–13.2, 13.3–15.8, 15.9–17.7, and 17.8–35.9 mg/L, respectively. The GDM rate was 15.96%, 13.10%, 13.64%, and 12.87% among women with gestational VE change of <0, 0–0.19, 0.20–0.29, ≥0.30 mg/L per week, respectively. Multivariable adjusted GAM analyses found that the first-trimester VE concentration was associated with the FPG levels and GDM risk in an L-shaped pattern; the FPG levels and GDM risk decreased sharply to a threshold (around 7 mg/L), and then were keep flat. Gestational VE decreases when the first-trimester VE level was less than 11 mg/L were related to increased FPG levels and GDM risk. Conclusions: Both low first-trimester VE levels and subsequent gestational VE decrease were related with increased risk of GDM. The findings suggest the necessity of having VE-rich foods and appropriate VE supplementation to prevent GDM for pregnant women with low baseline VE levels.

BmCBP Catalyzes the Acetylation of BmApoLp-II Protein and Regulates Its Stability in Silkworm, Bombyx mori

Acetylation is an important and reversible post-translational modification (PTM) of protein, which is involved in many cellular physiological processes. In previous studies, lots of nutrient storage proteins were found to be highly acetylated in silkworms, and acetylation can improve the stability of these proteins. However, the related acetyltransferase was not involved. In the present work, a Bombyx mori nutrient storage protein, apolipophorin II (BmApoLp-II), was further confirmed to be acetylated, and the acetylation could improve its protein expression. Furthermore, RNAi and Co-IP showed that the acetyltransferase BmCBP was found to catalyze the acetylation modification of BmApoLp-II, and thus affect its protein expression. Meanwhile, it was proved that acetylation could improve the stability of the BmApoLp-II protein by completing its ubiquitination. These results lay a foundation for further study on the mechanism of regulating nutrition storage and hydrolysis utilization of storage proteins by BmCBP and the acetylation in the silkworm Bombyx mori.

First demonstration of a fiber optic bolometer on a tokamak plasma (invited)

A fiber optic bolometer (FOB) was demonstrated observing a fusion plasma for the first time at the DIII-D tokamak. A FOB uses a fiber optics-based interferometric technique that is designed to have a high sensitivity to temperature changes [75 mK/(W/m²) responsivity in high vacuum with 0.38 mK noise level] with a negligible susceptibility to electromagnetic interference (EMI) that can be problematic for resistive bolometers in a tokamak environment. A single-channel test apparatus was installed on DIII-D consisting of a measurement FOB and shielded reference FOB. The single-channel FOB showed a negligible increase in the noise level during typical plasma operations (0.39 mK) compared to the benchtop results (0.38 mK), confirming an insignificant EMI impact to the FOB. Comparisons to DIII-D resistive bolometers showed good agreement with the single-channel FOB, indicating that the FOB is comparable to a resistive bolometer when the impulse calibration is applied. The noise-equivalent power density of the calibrated FOB during a plasma operation was 0.55 W/m² with an average sampling time of 20 ms. The major potential effect of ionizing radiation on the FOB would be the radiation-induced attenuation, which can be efficiently compensated for by adjusting the probing light power.

The emerging role of circular RNAs in drug resistance of non-small cell lung cancer

Due to the characteristics of aggressiveness and high risk of postoperative recurrence, non-small cell lung cancer (NSCLC) is a serious hazard to human health, accounting for 85% of all lung cancer cases. Drug therapies, including chemotherapy, targeted therapy and immunotherapy, are effective treatments for NSCLC in clinics. However, most patients ultimately develop drug resistance, which is also the leading cause of treatment failure in cancer. To date, the mechanisms of drug resistance have yet to be fully elucidated, thus original strategies are developed to overcome this issue. Emerging studies have illustrated that circular RNAs (circRNAs) participate in the generation of therapeutic resistance in NSCLC. CircRNAs mediate the modulations of immune cells, cytokines, autophagy, ferroptosis and metabolism in the tumor microenvironment (TME), which play essential roles in the generation of drug resistance of NSCLC. More importantly, circRNAs function as miRNAs sponges to affect specific signaling pathways, directly leading to the generation of drug resistance. Consequently, this review highlights the mechanisms underlying the relationship between circRNAs and drug resistance in NSCLC. Additionally, several therapeutic drugs associated with circRNAs are summarized, aiming to provide references for circRNAs serving as potential therapeutic targets in overcoming drug resistance in NSCLC.

Interaction of acetic acid bacteria and lactic acid bacteria in multispecies solid-state fermentation of traditional Chinese cereal vinegar

The microbial community plays an important role on the solid-state fermentation (SSF) of Chinese cereal vinegar, where acetic acid bacteria (AAB) and lactic acid bacteria (LAB) are the dominant bacteria. In this study, the top-down (in situ) and bottom-up (in vitro) approaches were employed to reveal the interaction of AAB and LAB in SSF of Shanxi aged vinegar (SAV). The results of high-throughput sequencing indicates that Acetobacter pasteurianus and Lactobacillus helveticus are the predominant species of AAB and LAB, respectively, and they showed negative interrelationship during the fermentation. A. pasteurianus CGMCC 3089 and L. helveticus CGMCC 12062, both of which were isolated from fermentation of SAV, showed no nutritional competition when they were co-cultured in vitro. However, the growth and metabolism of L. helveticus CGMCC 12062 were inhibited during SSF due to the presence of A. pasteurianus CGMCC 3089, indicating an amensalism phenomenon between these two species. The transcriptomic results shows that there are 831 differentially expressed genes (|log2 (Fold Change)| > 1 and, p ≤ 0.05) in L. helveticus CGMCC 12062 under co-culture condition comparing to its mono-culture, which are mainly classified into Gene Ontology classification of molecular function, biological process, and cell composition. Of those 831 differentially expressed genes, 202 genes are up-regulated and 629 genes are down-regulated. The down-regulated genes were enriched in KEGG pathways of sugar, amino acid, purine, and pyrimidine metabolism. The transcriptomic results for A. pasteurianus CGMCC 3089 under co-culture condition reveals 529 differentially expressed genes with 393 up-regulated and 136 down-regulated, and the genes within KEGG pathways of sugar, amino acid, purine, and pyrimidine metabolism are up-regulated. Results indicate an amensalism relationship in co-culture of A. pasteurianus and L. helveticus. Therefore, this work gives a whole insight on the interaction between the predominant species in SSF of cereal vinegar from nutrient utilization, endogenous factors inhibition and the regulation of gene transcription.

Involvement of PtPHR1 in phosphates starvation-induced alkaloid biosynthesis in Pinellia ternata (Thunb.) Breit

Nowadays, because of the great benefit to human health, more and more efforts have been made to increase the production of alkaloids in Pinellia ternata (Thunb.) Breit. Phosphate (Pi) plays a critical role in plant growth and development, as well as secondary metabolism. However, its effect and regulation mechanism of Pi signaling on alkaloid biosynthesis call for further exploration. Here, we reported that Pi starvation could induce alkaloid accumulation in P. ternata. We cloned a cDNA sequence encoding PtPHR1 from P. ternata, which was further identified by nuclear localization, transcription activity, and binding ability to the PHR1-binding sequence. We found that the transformation of PtPHR1 into the Arabidopsis phr1 mutant (designated as PtPHR1OE/phr1) led to the rescue of the phenotype of the phr1 mutant to that of the wild-type, including the expression level of Pi starvation-induced genes and anthocyanin accumulation. The combination of these biochemical and genetic experiments indicated that PtPHR1 was intended to have a role similar to that of AtPHR1 in Pi signaling and metabolic responses. Interestingly, we found that Pi starvation also induced the production of benzoic acid, an intermediate in the biosynthetic pathway of phenylpropylamino alkaloids. Furthermore, this induction effect was impaired in the phr1 mutant but partly recovered in PtPHR1OE/phr1 plants. Together, our data suggest that Pi starvation promoted benzoic acid-derived alkaloid biosynthesis in P. ternata under the control of PtPHR1. Our finding that PtPHR1 is involved in the regulation of Pi signaling on alkaloid biosynthesis shows a direct link between the Pi nutrient supply and secondary metabolism.

Abstract 2568: ARTS-021 is a potent and selective CDK2 inhibitor that demonstrates anti-cancer activity in preclinical cancer models with CCNE1 amplification

Cyclin E1 amplification is prevalent in cancers with high unmet medical need such as high grade serous ovarian cancer, stomach cancer and esophageal cancer. Cancer cell lines with high expression level of cyclin E1 gene exhibited profound sensitivity to CDK2 gene depletion, suggesting CDK2 selective inhibitors have the potential to treat patients harboring Cyclin E1 alterations. Here we report the development and preclinical characterization of ARTS-021, an orally bioavailable small molecule CDK2 selective inhibitor. In enzymatic assay against a panel of different CDKs, ARTS-021 potently inhibits the activity of CDK2/CyclinE1 complex with 50% inhibitory concentration (IC50) in the sub-nanomolar range, displaying superior selectivity against other CDKs (CDK1,4,6,7,9). Very low hit rate (S(10)=0.022, at 1uM) is observed when ARTS-021 is assessed in whole Kinome profiling, further revealing the selectivity of this compound. ARTS-021 also demonstrates potent CDK2 inhibition and selectivity against other CDK family members (CDK1,4,6,9) in a series of cellular assays. Consistent with genetic CDK2 dependence data, cell lines with CCNE1 amplification are particularly sensitive to ARTS-021. Double nanomolar ARTS-021 inhibits Rb phosphorylation and blocks G1/S transition, leading to cell growth arrest specifically in CCNE1 amplified cell lines. This CDK2 dependent anti-tumor activity is further validated in vivo, where daily ARTS-021 administration leads to tumor stasis in CCNE1 amplified but not wild type xenograft models. Taken together, these data demonstrate ARTS-021 as a promising CDK2 selective inhibitor with strong potential towards the development of effective therapies for CCNE1 altered cancer.

Citation Format: jiaqi Liang, Dai Cheng, Yali Guo, xiaobin zhang, Xipan Liu, Jia Fu, Qiang Ding, Wen Xiong, Fang Li, Yaoyu Chen, Qing Sheng. ARTS-021 is a potent and selective CDK2 inhibitor that demonstrates anti-cancer activity in preclinical cancer models with CCNE1 amplification [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2568.

A First-in-Human, Phase 1, Multicenter, Open-label, Dose-Escalation Study of PCA062, an Antibody-Drug Conjugate Targeting P-Cadherin, in Patients with Solid Tumors

This first-in-human (FIH), phase 1, multicenter, open-label study was conducted to characterize the safety, tolerability, pharmacokinetics, and preliminary efficacy, and to establish the maximum tolerated dose (MTD)/recommended dose for expansion (RDE) of PCA062 in patients with solid tumors. Adult patients with any solid tumor type and having a documented P-cadherin-positive tumor were enrolled; exceptions to P-cadherin positivity requirement were head and neck squamous cell carcinomas (HNSCC) and esophageal squamous cell carcinoma (ESCC). Dose escalation was guided by an adaptive Bayesian logistic regression model with escalation with overdose control to determine the MTD/RDE. Forty-seven patients were treated at 10 different dose levels of PCA062, ranging from 0.4 to 5.0 mg/kg Q2W administered as a 1-hour intravenous infusion. All enrolled patients discontinued the treatment; primary reason for discontinuation was progressive disease (78.7%). All 47 patients experienced at least one AE, of which 32 patients had a grade {greater than or equal to}3 AE and 37 patients experienced AEs suspected to be study drug related. The MTD of PCA062 was 3.6 mg/kg Q2W and thrombocytopenia was reported as a DLT that was attributed to the known toxicities of the DM1 payload with no P cadherin-related toxicities. PK was proportional, and no patients developed antidrug antibodies, suggesting adequate exposure at the doses tested. One patient out of 47 achieved a partial response and there was no correlation between tumor P-cadherin expression and clinical efficacy. Due to limited anti-tumor activity at the maximally tolerated dose level, Novartis has terminated clinical development of PCA062 (NCT02375958).

The Acetylation Modification of SP1 Regulates the Protein Stability in Silkworm

Acetylation is a highly conservative and reversible post-translational modification. Acetylation modification can regulate gene expression by altering protein function and is widely identified in an increasing number of species. Previously, the acetylated proteome of silkworm was identified by combining acetylated polypeptide enrichment with nano-HPLC/MS/MS; the identification revealed that the SP proteins (SPs) were high acetylated. In this study, the acetylation of SP1, one of the SPs, was further confirmed using immunoprecipitation (IP) and Western blotting. Then, we found the acetylation could upregulate SP1 protein expression by enhancing the protein stability. Further research found that the acetylation of SP1 protein can competitively inhibit its ubiquitination and thus improve the stability and cell accumulation of SP1 protein by inhibiting the ubiquitin-mediated proteasome degradation pathway. This result provides a basis for acetylation to regulate the nutrient storage and utilization of silkworm.

A Phase I Study of LSZ102, an Oral Selective Estrogen Receptor Degrader, with or without Ribociclib or Alpelisib, in Patients with Estrogen Receptor-Positive Breast Cancer

PURPOSE

Data are sparse for oral selective estrogen receptor (ER) degraders (SERD) in cancer treatment. The investigational oral SERD LSZ102 was assessed in monotherapy and combination use in a phase I study.

PATIENTS AND METHODS

A phase I, multicenter, open-label dose-escalation study (NCT02734615) of LSZ102 alone (arm A; n = 77) or with ribociclib (arm B; n = 78) or alpelisib (arm C; n = 43) in heavily pretreated adults with histologically confirmed ER-positive breast cancer and prior disease progression. Arm A received LSZ102 200-900 mg/day; arm B, LSZ102 200-600 mg/day plus ribociclib 300-600 mg/day; arm C, LSZ102 300-450 mg/day plus alpelisib 200-300 mg/day. Key outcomes were dose-limiting toxicities (DLT) in the first 28-day treatment cycle, adverse events (AE), laboratory parameters, pharmacokinetics, biopsy ER protein, and investigator-assessed clinical response (RECIST v1.1).

RESULTS

The most common AEs were gastrointestinal. Treatment-related serious AEs occurred in 10% of participants (19/198), mostly in arm C [10/43 (23%)]. DLTs occurred in: arm A, 5% (4/77); arm B, 3% (2/78); and arm C, 19% (8/43). LSZ102 exposure was slightly greater than dose proportional. On-treatment biopsy ER reductions were observed, with a trend toward an LSZ102 dose response. Objective response rates (95% confidence interval) were: arm A, 1.3% (0.0-7.0); arm B, 16.9% (9.3-27.1); and arm C, 7.0% (1.5-19.1), and clinical benefit rates 7.8% (2.9-16.2), 35.1% (24.5-46.8), and 20.9% (10.0-36.0), respectively.

CONCLUSIONS

LSZ102 was well tolerated alone and with ribociclib and had a manageable safety profile with alpelisib. Preliminary clinical activity was observed in combination use.

The acetylation modification regulates the stability of Bm30K-15 protein and its mechanism in silkworm, Bombyx mori

The 30 K proteins are the major silkworm hemolymph proteins and are involved in a variety of physiological processes, such as nutrient and energy storage, embryogenesis, immune response, and inhibition of apoptosis. The Bm30K-15 protein is one of the 30 K proteins and is abundant in the hemolymph of fifth instar silkworm larva. We previously found that the Bm30K-15 protein can be acetylated. In the present study, we found that acetylation can improve the protein stability of Bm30K-15. Further exploration confirmed that the increase in protein stability by acetylation was caused by competition between acetylation and ubiquitination. In summary, these findings aim to provide insight into the effect of acetylation modification on the protein level and stability of the Bm30K-15 and the possible molecular mechanism of its existence in silkworm, Bombyx mori.

Daphnetin inhibits spinal glial activation via Nrf2/HO-1/NF-κB signaling pathway and attenuates CFA-induced inflammatory pain

Daphnetin (7, 8-dihydroxycoumarin, DAPH), a coumarin derivative isolated from Daphne odora var., recently draws much more attention as a promising drug candidate to treat neuroinflammatory diseases due to its protective effects against neuroinflammation. However, itscontribution to chronic inflammatory pain is largely unknown. In the current work, we investigated the effects of DAPH in a murine model of inflammatory pain induced by complete Freund's adjuvant (CFA) and its possible underlying mechanisms. Our results showed that DAPH treatment significantly attenuated mechanical allodynia provoked by CFA. A profound inhibition of spinal glial activation, followed by attenuated expression levels of spinal pro-inflammatory cytokines, was observed in DAPH-treated inflammatory pain mice. Further study demonstrated that DAPH mediated negative regulation of spinal NF-κB pathway, as well as its preferential activation of Nrf2/HO-1 signaling pathway in inflammatory pain mice. This study, for the first time, indicated that DAPH might preventthe development of mechanical allodynia in mice with inflammatory pain. And more importantly, these data provide evidence for the potential application of DAPH in the treatment of chronic inflammatory pain.

PCA062, a P-cadherin Targeting Antibody-Drug Conjugate, Displays Potent Antitumor Activity Against P-cadherin-expressing Malignancies

The cell surface glycoprotein P-cadherin is highly expressed in a number of malignancies, including those arising in the epithelium of the bladder, breast, esophagus, lung, and upper aerodigestive system. PCA062 is a P-cadherin specific antibody-drug conjugate that utilizes the clinically validated SMCC-DM1 linker payload to mediate potent cytotoxicity in cell lines expressing high levels of P-cadherin in vitro, while displaying no specific activity in P-cadherin-negative cell lines. High cell surface P-cadherin is necessary, but not sufficient, to mediate PCA062 cytotoxicity. In vivo, PCA062 demonstrated high serum stability and a potent ability to induce mitotic arrest. In addition, PCA062 was efficacious in clinically relevant models of P-cadherin-expressing cancers, including breast, esophageal, and head and neck. Preclinical non-human primate toxicology studies demonstrated a favorable safety profile that supports clinical development. Genome-wide CRISPR screens reveal that expression of the multidrug-resistant gene ABCC1 and the lysosomal transporter SLC46A3 differentially impact tumor cell sensitivity to PCA062. The preclinical data presented here suggest that PCA062 may have clinical value for treating patients with multiple cancer types including basal-like breast cancer.

Structural and functional organization of the MYC transcriptional factors in Camellia sinensis

Genome-wide identification, expression analysis of the MYC family in Camellia sinensis, and potential functional characterization of CsMYC2.1 have laid a solid foundation for further research on CsMYC2.1 in jasmonate (JA)-mediated response. Myelocytomatosis (MYC) of basic helix-loop-helix (bHLH) plays a major role in JA-mediated plant growth and developmental processes through specifically binding to the G-box in the promoters of their target genes. In Camellia sinensis, studies on the MYC gene family are limited. Here, we identified 14 C. sinensis MYC (CsMYC) genes, and further analyzed the evolutionary relationship, gene structure, and motif pattern among them. The expression patterns of these CsMYC genes in different tissues suggested their important roles in diverse function in tea plant. Four MYC transcription factors with the highest homology to MYC2 in Arabidopsis were localized in the nucleus. Two of them, named CsMYC2.1 and CsMYC2.2, exhibited transcriptional self-activating activity, and, therefore, could significantly activate the promoter containing G-box motif, whereas CsJAM1.1 and CsJAM1.2 lack the transcriptional self-activating activity, indirectly mediating the JA pathway through interacting with CsMYC2.1 and CsMYC2.2. Furthermore, Yeast Two-Hybrid (Y2H) and Bimolecular Fluorescent Complimentary (BiFC) assays showed that CsMYC2.1 could interact with CsJAZ3/7/8 proteins. Genetically, the complementation of CsMYC2.1 in myc2 mutants conferred the ability to restore the sensitivity to JA signals. The results provide a comprehensive characterization of the 14 CsMYCs in C. sinensis, establishing a solid foundation for further research on CsMYCs in JA-mediated response.

PM2.5 Induces the Expression of Inflammatory Cytokines via the Wnt5a/Ror2 Pathway in Human Bronchial Epithelial Cells

Background and Purpose

Recently, fine particulate matter (PM2.5) was identified as the main exposure risk for COPD, and inflammation is central to the development of COPD. In this study, we investigated whether PM2.5 can induce the secretion of interleukin-6 (IL-6), IL-8 and IL-1β in human bronchial epithelial cells (HBECs) in vitro via the wingless-related integration site 5A (Wnt5a)/receptor tyrosine kinase-like orphan receptor 2 (Ror2) signaling.

Methods

The expression of Wnt5a and Ror2 was assessed by immunohistochemistry in motor vehicle exhaust (MVE)-induced Sprague-Dawley rats. HBECs were transfected with small interfering RNA (siRNA) targeting Wnt5a or Ror2 and subsequently stimulated with PM2.5.The secretion of IL-6, IL-8 and IL-1β was assessed by ELISAs, and the expression of Wnt5a/Ror2 signaling were assessed by RT-PCR and Western blotting.

Results

Both Wnt5a and Ror2 protein were increased in the lung of MVE-induced rats. HBECs exposed to PM2.5 for 24 h significantly upregulated Wnt5a and Ror2 expression and subsequently promoted the nuclear translocation of NF-κB, which increased the production of IL-1β, IL-6 and IL-8. Wnt5a siRNA prevented these outcomes. Wnt5a antagonist (BOX5) also prevented inflammatory effects. Furthermore, Ror2 siRNA blocked the NF-κB activity and inhibited the release of IL-6, IL-8 and IL-1β from PM2.5-exposed HBECs.

Conclusion

PM2.5 induces the secretion of IL-6, IL-8 and IL-1β in HBECs via the Wnt5a/Ror2 signaling, demonstrating a novel mechanism for PM2.5-associated airway inflammation.

Identification and Investigation of miRNAs From Gastrodia elata Blume and Their Potential Function

Gastrodia elata Blume (G. elata) is a valuable traditional Chinese medicine with neuroprotection, anti-inflammatory, and immune regulatory functions. MicroRNAs (miRNA) is a kind of endogenous noncoding small RNAs that plays distinctly important roles for gene regulation of organisms. So far, the research on G. elata is mainly focused on the pharmacological functions of the natural chemical ingredients, and the function of G. elata miRNA remains unknown. In this study, 5,718 known miRNAs and 38 novel miRNAs were identified by high-throughput sequencing from G. elata. Based on GO and KEGG analysis, we found that the human genes possibly regulated by G. elata miRNAs were related to the cell cycle, immune regulation, intercellular communication, etc. Furthermore, two novel miRNAs as Gas-miR01 and Gas-miR02 have stable and high expression in the medicinal tissues of G. elata. Further bioinformatics prediction showed that both Gas-miR01 and Gas-miR02 could target Homo sapiens A20 gene, furthermore, the dual-luciferase reporter gene assay and Western Blotting verified the interaction of Gas-miR01 or Gas-miR02 with A20. These evidences suggested that G. elata-unique miRNAs might be involved in certain physiological processes. The animal experiment showed that Gas-miR01 and Gas-miR02 could be detected in some tissues of mice by intragastric administration; meanwhile, the A20 expression in some tissues of mice was downregulated. These results supported for the functional study of G. elata miRNAs.

Efficient and risk-reduced genome editing using double nicks enhanced by bacterial recombination factors in multiple species

Site-specific DNA double-strand breaks have been used to generate knock-in through the homology-dependent or -independent pathway. However, low efficiency and accompanying negative impacts such as undesirable indels or tumorigenic potential remain problematic. In this study, we present an enhanced reduced-risk genome editing strategy we named as NEO, which used either site-specific trans or cis double-nicking facilitated by four bacterial recombination factors (RecOFAR). In comparison to currently available approaches, NEO achieved higher knock-in (KI) germline transmission frequency (improving from zero to up to 10% efficiency with an average of 5-fold improvement for 8 loci) and 'cleaner' knock-in of long DNA fragments (up to 5.5 kb) into a variety of genome regions in zebrafish, mice and rats. Furthermore, NEO yielded up to 50% knock-in in monkey embryos and 20% relative integration efficiency in non-dividing primary human peripheral blood lymphocytes (hPBLCs). Remarkably, both on-target and off-target indels were effectively suppressed by NEO. NEO may also be used to introduce low-risk unrestricted point mutations effectively and precisely. Therefore, by balancing efficiency with safety and quality, the NEO method reported here shows substantial potential and improves the in vivo gene-editing strategies that have recently been developed.

Increased lysosomal biomass is responsible for the resistance of triple-negative breast cancers to CDK4/6 inhibition

Inhibitors of cyclin-dependent kinases CDK4 and CDK6 have been approved for treatment of hormone receptor-positive breast cancers. In contrast, triple-negative breast cancers (TNBCs) are resistant to CDK4/6 inhibition. Here, we demonstrate that a subset of TNBC critically requires CDK4/6 for proliferation, and yet, these TNBC are resistant to CDK4/6 inhibition due to sequestration of CDK4/6 inhibitors into tumor cell lysosomes. This sequestration is caused by enhanced lysosomal biogenesis and increased lysosomal numbers in TNBC cells. We developed new CDK4/6 inhibitor compounds that evade the lysosomal sequestration and are efficacious against resistant TNBC. We also show that coadministration of lysosomotropic or lysosome-destabilizing compounds (an antibiotic azithromycin, an antidepressant siramesine, an antimalaria compound chloroquine) renders resistant tumor cells sensitive to currently used CDK4/6 inhibitors. Lastly, coinhibition of CDK2 arrested proliferation of CDK4/6 inhibitor-resistant cells. These observations may extend the use of CDK4/6 inhibitors to TNBCs that are refractory to current anti-CDK4/6 therapies.

The stability and antiapoptotic activity of Bm30K-3 can be improved by lysine acetylation in the silkworm, Bombyx mori

Acetylation is an important, highly conserved, and reversible post-translational modification of proteins. Previously, we showed by nano-HPLC/MS/MS that many nutrient storage proteins in the silkworm are acetylated. Among these proteins, most of the known 30K proteins were shown to be acetylated, including 23 acetylated 30K proteins containing 49 acetylated sites (Kac), indicating the importance of the acetylation of 30K proteins in silkworm. In this study, Bm30K-3, a 30K protein containing three Kac sites, was further assessed in functional studies of its acetylation. Increasing the level of Bm30K-3 acetylation by adding the deacetylase inhibitor trichostatin A (TSA) increased the levels of this protein and further inhibited cellular apoptosis induced by H₂ O₂ . In contrast, decreasing the level of acetylation by adding the acetylase inhibitor C646 could reduce the level of Bm30K-3 and increase H₂ O₂ -induced apoptosis. Subsequently, BmN cells were treated with CHX and MG132, and increasing the acetylation level using TSA was shown to inhibit protein degradation and improve the stability of Bm30K-3. Furthermore, the acetylation of Bm30K-3 could compete with its ability to be ubiquitinated, suggesting that acetylation could inhibit the ubiquitin-mediated proteasome degradation pathway, improving the stability and accumulation of proteins in cells. These results further indicate that acetylation might regulate nutrition storage and utilization in Bombyx mori, which requires further study.

Glomerular endothelial derived vesicles mediate podocyte dysfunction: A potential role for miRNA

MicroRNAs (miRNA) are shown to be involved in the progression of several types of kidney diseases. Podocytes maintain the integrity of the glomerular basement membrane. Extracellular vesicles (EV) are important in cell-to-cell communication as they can transfer cellular content between cells, including miRNA. However, little is known about how extracellular signals from the glomerular microenvironment regulate podocyte activity. Using a non-contact transwell system, communication between glomerular endothelial cells (GEnC) and podocytes was characterised in-vitro. Identification of transferred EV-miRNAs from GEnC to podocytes was performed using fluorescence cell tracking and miRNA mimetics. To represent kidney disease, podocyte molecular profiling and functions were analysed after EV treatments derived from steady state or activated GEnC. Our data shows activation of GEnC alters EV-miRNA loading, but activation was not found to alter EV secretion. EV delivery of miRNA to recipient podocytes altered cellular miRNA abundance and effector functions in podocytes, including decreased secretion of VEGF and increased mitochondrial stress which lead to altered cellular metabolism and cytoskeletal rearrangement. Finally, results support our hypothesis that miRNA-200c-3p is transfered by EVs from GEnC to podocytes in response to activation, ultimately leading to podocyte dysfunction.

Abstract P4-10-07: Tumor ER protein modulation, molecular characterization and monitoring of cfDNA in phase 1 study of LSZ102 and LSZ102 + ribociclib in patients with ER+ MBC

Background: LSZ102 is an orally bioavailable selective estrogen receptor degrader (SERD) that inhibits estrogen receptor (ER) mediated gene transcription, induces receptor degradation, and blocks ER-dependent cell growth in preclinical models. This first-in-human study of LSZ102 is evaluating LSZ102 as a single agent (SA) and in combination with the CDK4/6 inhibitor ribociclib or the PI3K inhibitor alpelisib (BYL719) in patients (pts) with locally advanced/metastatic ER-positive (ER+) breast cancer (BC). Here, we present the immunohistochemistry (IHC) and circulating tumor DNA (ctDNA) data obtained from a subset of pts treated with either LSZ102 SA or the combination of LSZ102 and ribociclib. Methods: ER IHC was performed with an antirabbit antibody (clone SP1) on FFPE samples collected at baseline and cycle 1 day 15 (C1D15), and the ER value was reported using the H-score method. A Novartis exploratory PanCancer next-generation sequencing ~600 gene panel for cell-free DNA (cfDNA) was used on plasma samples collected from pts treated with SA or the combination at baseline, on treatment (C1D1, C2D1/C3D1, C5D1, CXD1) at radiological assessments and at the end of treatment (EOT). Results: One hundred fifty-three pts with MBC (median number of prior lines of therapy in metastatic setting = 4; range, 0-10) were treated with LSZ102 SA or the combination of LSZ102 and ribociclib (data cutoff, November 30, 2018). ER protein levels, assessed by IHC H-score, are downregulated in about 75% of C1D15 samples in both SA and combination-treated pts. In this cohort of heavily pretreated pts, cfDNA sequencing was performed on approximately 400 samples from 135 pts, and the genomic landscape is described both at baseline and EOT for pts with detectable ctDNA (~77% of pts). At baseline, approximately 40% of pts had mutations in the ESR1 ligand-binding domain (LBD), and approximately 40% of pts had PIK3CA activating mutations. LBD ESR1 mutations were mainly subclonal with several pts harboring multiple mutations at baseline. The frequency of ESR1 Y537S mutation was no higher in EOT samples after LSZ102 treatment compared with baseline. Moreover, the tumor reduction of target lesions &gt; 30% was observed in pts harboring different baseline ESR1 mutations, including Y537S, treated with either SA or the combination. Furthermore, the longitudinal cfDNA analysis showed a consistent reduction of the overall circulating tumor fraction (ctDNA fraction), from baseline for the majority of patients who achieved either partial response or stable disease with either SA or the combination. Conclusions: Consistent with being a SERD, LSZ102 treatment leads to the degradation of ER in tumor biopsies. The addition of ribociclib does not alter LSZ102-induced ER downregulation. The most common genetic alterations found in cfDNA collected from enrolled ER+ MBC patients before the study treatment were ESR1 and PIK3CA mutations. Importantly, the antitumor activity was observed in pts harboring a variety of ESR1 LBD mutations. Furthermore, enrichment of ESR1 Y537S mutations was not observed after LSZ102 treatment. Finally, the on-treatment longitudinal assessment of cfDNA measuring ctDNA fraction and mutation dynamics is maturing as a useful tool for monitoring the treatment efficacy.

Citation Format: Komal Jhaveri, Dejan Juric, Sara Cresta, Yoon-Sim Yap, Francois P. Duhoux, Catherine Terret, Rachel Layman, Alejandro Balbin, Qing Sheng, Serena Liao, Adam Crystal, Giuseppe Curigliano. Tumor ER protein modulation, molecular characterization and monitoring of cfDNA in phase 1 study of LSZ102 and LSZ102 + ribociclib in patients with ER+ MBC [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-10-07.

The effect of acetylation on the protein stability of BmApoLp-III in the silkworm, Bombyx mori

Acetylation is an important, reversible posttranslational modification to a protein. In a previous study, we found that there were a large number of acetylated sites in various nutrient storage proteins of the silkworm haemolymph. In this study, we confirmed that acetylation can affect the stability of nutrient storage protein Bombyx mori apolipophorin-III (BmApoLp-III). First, the expression of BmApoLp-III could be upregulated when BmN cells were treated with the deacetylase inhibitor panobinostat (LBH589); similarly, the expression was downregulated when the cells were treated with the acetylase inhibitor C646. Furthermore, the increase in acetylation by LBH589 could inhibit the degradation and improve the accumulation of BmApoLp-III in BmN cells treated with cycloheximide and MG132 respectively. Moreover, we found that an increase in acetylation could decrease the ubiquitination of BmApoLp-III and vice versa; therefore, we predicted that acetylation could improve the stability of BmApoLp-III by competing for ubiquitination and inhibiting the protein degradation pathway mediated by ubiquitin. Additionally, BmApoLp-III had an antiapoptosis function that increased after LBH589 treatment, which might have been due to the improved protein stability after acetylation. These results have laid the foundation for further study on the mechanism of acetylation in regulating the storage and utilization of silkworm nutrition.

Cisplatin-mediated down-regulation of miR-145 contributes to up-regulation of PD-L1 via the c-Myc transcription factor in cisplatin-resistant ovarian carcinoma cells

Immune tolerance is one of the leading causes of chemotherapy resistance in carcinoma cases. Studies have shown that programmed cell death ligand-1 (PD-L1), an inhibitory molecule expressed by cancer cells, plays a significant role in immune tolerance through the induction of T cell dysfunction. The results of our RNA sequencing in previous studies revealed that microRNA-145 (miR-145), which is known to be down-regulated by cisplatin in cisplatin-resistant ovarian cancer cells, also represses gene PD-L1 expression. However, the mechanism by which miR-145 contributes to regulate PD-L1 expression in cisplatin resistance of ovarian cancer is yet to be fully understood. Here, we show that cisplatin-mediated miR-145 down-regulation increased PD-L1 expression via targeting the c-Myc transcription factor, thereby inducing T cell apoptosis in vitro. We also report that expression of miR-145 is negatively correlated with PD-L1 expression in human ovarian cancer tissues, malignant grades and the recurrent risks of ovarian cancer after chemotherapy. In summary, our findings suggest that the miR-145/c-Myc/PD-L1 axis contributes to cisplatin resistance in ovarian cancer and support that miR-145 might act as an adjuvant therapeutic target in chemotherapy of ovarian cancer.

Abstract 922: Preclinical anticancer activity of LSZ102, a novel oral selective estrogen receptor degrader targeting wild-type and mutant ER

Estrogen receptor (ER) blockade is a well-established therapeutic approach in ER+ breast cancer. A novel oral selective estrogen receptor degrader (SERD), LSZ102, is in development. LSZ102 induces proteasome-mediated degradation of both wild type and mutant ERα in MCF-7 cells. LSZ102 also inhibits transcription of ERα target genes and results in a decrease in cell proliferation in a dose dependent manner. Expression of ERα Y537S results in a shift in inhibition of cell proliferation upon incubation with either LSZ102 or fulvestrant; however, the shift with LSZ102 was less severe. Similarly, LSZ102 induced a more pronounced level of ERα degradation than fulvestrant in the Y537S mutant MCF7 cells. Overall, LSZ102 is effective in the wild type and Y537S ERα mutant setting in vitro. In vivo, LSZ102 treatment of ER+ breast cancer xenografts resulted in inhibition of ERα regulated transcripts and a decrease in ERα protein levels. In the MCF7 xenograft model, expression of ERα Y537S resulted in reduced activity by fulvestrant, but not by LSZ102. In vivo, LSZ102 exhibited single agent and combination efficacy upon co-administration with the CDK4/6 inhibitor ribociclib and the alpha-specific PI3K inhibitor alpelisib. LSZ102 is currently in a Phase I clinical trial in patients with ER+ breast cancer in which it is tested as a single agent, and in combination with either ribociclib or alpelisib.

Citation Format: L. Alex Gaither, Choi Lai Tiong Yip, Chunrong Wang, Weiyi Toy, Qing Sheng, Jinyun Chen, Yuji Mishina, Rita Das, Stefan Peukert, Alice Loo, Sarat Chandarlapaty, Adam Crystal, Tinya J. Abrams. Preclinical anticancer activity of LSZ102, a novel oral selective estrogen receptor degrader targeting wild-type and mutant ER [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 922.

Abstract 4743: Using genome-wide CRISPR screen to understand resistance mechanisms to PCA062, a P-cadherin targeting antibody-drug conjugate

P-cadherin (PCAD) is a member of the cadherin family that mediates calcium dependent cell-cell contacts in adherens-type junctions of epithelium. Expression of P-cadherin is high in malignant tumors of epithelial origin, such as breast, esophagus, head and neck cancers, but low in normal tissues. This expression pattern makes P-cadherin a potential good target for antibody-drug conjugates (ADCs). PCA062 is a first-in-class antibody drug conjugate targeting P-cadherin. PCA062 consists of a fully human anti-P-cadherin antibody of the IgG1/κ subtype, a non-cleavable bi-functional linker (SMCC) and a maytansine-derived cytotoxic payload (DM1, with a target average drug to antibody ratio (DAR) of 3.8).

PCA062 activity was examined in a collection of cell lines expressing high level of PCAD. A subset of these PCAD high cell lines are resistant to PCA062 treatment while they remain sensitive to DM1, suggesting defects in the process of PCA062 uptake or the processing and release of DM1 into the cytoplasmic compartment. PCA062 internalization rate was measured by the uptake of a fluorescent dye labeled anti-PCAD antibody (CQY684, the Ab portion of PCA062) in both PCA062 sensitive and resistant lines. PCA062 resistant lines show slower CQY684 internalization as compared to PCA062 sensitive lines, indicating a defect in ADC internalization may contribute to PCA062 resistance. To explore additional resistance mechanisms to PCA062 as well as to find critical components for PCA062 internalization, a genome wide CRISPR screen was performed in PCA062 sensitive HCC1954 and in PCA062 resistant KYSE510 cell line in the presence and absence of PCA062 and DM1 to look for genes that when knocked out may specifically modulate PCA062 sensitivity. The multi-drug resistant gene MRP1 is a strong hit for PCA062 sensitization in both PCA062 resistant KYSE510 and PCA062 sensitive HCC1954 cells. Lysosomal transporter SLC46A3 and Saga transcription complex components are strong rescue hits for PCA062 in HCC1954. These data suggest that in addition to target expression level and cell intrinsic sensitivity to payload, genes involved in ADC internalization and payload cytoplasmic accumulation will also impact tumor cell sensitivity to ADCs.

Citation Format: Angela Tam, Mark Zambrowski, Katherine Seiss, Si-Qi Liu, Tinya Abrams, Giordano Caponigro, William Tschantz, Jennifer Campbell, Tony DAlessio, Qing Sheng. Using genome-wide CRISPR screen to understand resistance mechanisms to PCA062, a P-cadherin targeting antibody-drug conjugate [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4743.

Bmo-miR-79 downregulates the expression of BmEm4 in the silkworm, Bombyx mori

MicroRNA is an important regulation factor in insect development and metamorphosis. It has been reported that E(spl)m4 is a miRNA-targeted gene, as well as the target of the Notch signaling pathway in Drosophila. The expression of E(spl)m4 can be regulated by microRNA and further affect the neural development of Drosophila. Here, we found that BmEm4, an ortholog of E(spl)m4 from Bombyx mori, was the target gene of bmo-miR-79, with target sites containing the Brd and K boxes of the BmEm4_3'UTR, which was validated by the dual luciferase reporter (DLR) assay. Furthermore, bmo-miR-79 mimics can inhibit the expression of BmEm4 in BmN cells after transfection, and bmo-miR-79 can also inhibit the expression of BmEm4 in different developmental stages of Bombyx mori at a posttranscriptional level, to different degrees. The EMSA test further showed that bmo-miR-79 could bind to BmAGO2, which is the Bombyx mori argonaute2 protein, suggesting that bmo-miR-79 might regulate the expression of BmEm4 by forming miRISC complexes with BmAGO2. Taken together, bmo-miR-79 could regulate the expression of BmEm4 mediated by BmAGO2 and further affect its function in the silkworm Bombyx mori.

WITHDRAWN: Effects of cancer-associated point mutations on the structure, function, and stability of succinate dehydrogenase A

This article has been withdrawn by the authors. Some of the SDHA enzyme activity data were flawed and were not performed and analyzed correctly. The withdrawing authors are in the process of correcting the data and re-evaluating them for resubmission.

Cloning, expression profiling, and acetylation identification of alpha-tubulin N-acetyltransferase 1 from Bombyx mori

Alpha-tubulin N-acetyltransferase 1 (ATAT1) is an acetyltransferase specific to α-tubulin and performs important functions in many cellular processes. Bombyx mori is an economic insect and also known as a model lepidoptera insect. In this study, we cloned a B. mori ATAT1 gene (BmATAT1) (Gen Bank accession number: XP_004932777.1). BmATAT1 contained an open reading frame (ORF) of 1,065 bp encoding 355 amino acids (aa). Expression profiling of BmATAT1 protein showed that the expression levels of BmATAT1 at different developmental stages and different tissues in fifth-instar larvae differ. BmATAT1 was highly expressed at the egg stage and in the head of the fifth-instar larvae. Subcellular localization showed that BmATAT1 was distributed in the cytoplasm and nucleus. Furthermore, BmATAT1 may lead to time-dependent induction of cell cycle arrest in the G2/M phase by flow cytometry analysis. Interestingly, using site-specific mutation, immunoprecipitation, and Western blotting, we further found a BmATAT1 acetylated site at K156, suggesting that this acetyltransferase could be regulated by acetylation itself.

The brain microenvironment mediates resistance in luminal breast cancer to PI3K inhibition through HER3 activation

Although targeted therapies are often effective systemically, they fail to adequately control brain metastases. In preclinical models of breast cancer that faithfully recapitulate the disparate clinical responses in these microenvironments, we observed that brain metastases evade phosphatidylinositide 3-kinase (PI3K) inhibition despite drug accumulation in the brain lesions. In comparison to extracranial disease, we observed increased HER3 expression and phosphorylation in brain lesions. HER3 blockade overcame the resistance of HER2-amplified and/or PIK3CA-mutant breast cancer brain metastases to PI3K inhibitors, resulting in marked tumor growth delay and improvement in mouse survival. These data provide a mechanistic basis for therapeutic resistance in the brain microenvironment and identify translatable treatment strategies for HER2-amplified and/or PIK3CA-mutant breast cancer brain metastases.

The Subthalamic Neurons are Activated by Both Orexin-A and Orexin-B

The subthalamic nucleus is an important nucleus in the indirect pathway of the basal ganglia circuit and therefore is involved in motor control under both normal and pathological conditions. Morphological studies reveal that the subthalamic nucleus receives relatively dense orexinergic projections originating from the hypothalamus. Both orexin-1 (OX₁) and orexin-2 (OX₂) receptors are expressed in the subthalamic nucleus. To explore the functions of orexinergic system in the subthalamic nucleus, extracellular electrophysiological recordings and behavioral tests were performed in the present study. Exogenous application of orexin-A significantly increased the spontaneous firing rate from 5.70 ± 0.66 Hz to 9.87 ± 1.18 Hz in 64.00% subthalamic neurons recorded. OX₁ receptors are involved in orexin-A-induced excitation. Application of orexin-B increased the firing rate from 7.47 ± 0.92 Hz to 11.85 ± 1.39 Hz in 80.95% subthalamic neurons recorded, entirely through OX₂ receptors. Both OX₁ and OX₂ receptor antagonists decreased the firing rate in 43.75% and 62.50% subthalamic neurons recorded respectively, suggesting the involvement of endogenous orexinergic system in the control of spontaneous firing activity. Further elevated body swing test revealed that microinjection of orexins and the receptor antagonists into the subthalamic nucleus induced contralateral-biased swing and ipsilateral-biased swing, respectively. Taken together, the present study suggests that orexins play important roles in the subthalamic nucleus which may provide further evidence for the involvement of subthalamic orexinergic tone in Parkinson's disease.

SIGNIFICANCE

Previous morphological studies indicate that the subthalamic nucleus receives orexinergic innervation and expresses both OX₁ and OX₂ receptors. Using in vivo multibarrel electrophysiological recordings, the present study revealed that exogenous application of orexin-A and orexin-B increased the spontaneous firing rate of the subthalamic neurons through OX₁ and OX₂ receptors. Endogenous orexinergic system was involved in the control of spontaneous firing of the subthalamic neurons. Further behavioral test revealed that intrasubthalamic application of orexins and the receptor antagonists induced biased swing behavior. The present study may provide further evidence for the involvement of subthalamic orexinergic tone in Parkinson's disease.

[Teaching research of Molecular Pharmacognosy for talent development in industry of Chinese medicinal materials under new situation]

The industry of Chinese medicinal materials is going through another high-level development stage with some important files issued by Chinese government in the past months, such as "the protection and development plans of Chinese medicinal materials (2015-2020)" and "the strategic development plans of Chinese medicine (2016-2030)". In addition, the effect of "TU Youyou" will not only improve the industry development, but also indicates the increasing international competition intensely. Therefore, one of the core problems of the sustainable-development industry is the training of senior talents under the "New Situation" with opportunity and intense competition. As one of the forefront courses of Chinese Pharmacology, Molecular Pharmacognosy (MP) is a new interdisciplinary science, which integrates the pharmacognosy and molecular biology, and combines many discipline theories and technological systems. MP not only inherits the traditional concepts,but also makes up for the shortages of pharmacognosy, and improves the development of pharmacognosy. Thus, these are importance of MP for cultivation of senior talents, and also the difficult teaching points of MP with no unified teaching mode. We will, in this paper, discuss the possible teaching modes through several aspects for talent cultivation and meeting the needs of social and industry development, such as teaching state of MP, the education of undergraduate and graduate students, social identity, and self renewal of curriculum theories and practice.

A phase I open-label dose-escalation study of the anti-HER3 monoclonal antibody LJM716 in patients with advanced squamous cell carcinoma of the esophagus or head and neck and HER2-overexpressing breast or gastric cancer

Background

Human epidermal growth factor receptor 3 (HER3) is important in maintaining epidermal growth factor receptor-driven cancers and mediating resistance to targeted therapy. A phase I study of anti-HER3 monoclonal antibody LJM716 was conducted with the primary objective to identify the maximum tolerated dose (MTD) and/or recommended dose for expansion (RDE), and dosing schedule. Secondary objectives were to characterize safety/tolerability, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity.

Methods

This open-label, dose-finding study comprised dose escalation, followed by expansion in patients with squamous cell carcinoma of the head and neck or esophagus, and HER2-overexpressing metastatic breast cancer or gastric cancer. During dose escalation, patients received LJM716 intravenous once weekly (QW) or every two weeks (Q2W), in 28-day cycles. An adaptive Bayesian logistic regression model was used to guide dose escalation and establish the RDE. Exploratory pharmacodynamic tumor studies evaluated modulation of HER3 signaling.

Results

Patients received LJM716 3–40 mg/kg QW and 20 mg/kg Q2W (54 patients; 36 patients at 40 mg/kg QW). No dose-limiting toxicities (DLTs) were reported during dose-escalation. One patient experienced two DLTs (diarrhea, hypokalemia [both grade 3]) in the expansion phase. The RDE was 40 mg/kg QW, providing drug levels above the preclinical minimum effective concentration. One patient with gastric cancer had an unconfirmed partial response; 17/54 patients had stable disease, two lasting >30 weeks. Down-modulation of phospho-HER3 was observed in paired tumor samples.

Conclusions

LJM716 was well tolerated; the MTD was not reached, and the RDE was 40 mg/kg QW. Further development of LJM716 is ongoing.

Trial registration

Clinicaltrials.gov registry number NCT01598077 (registered on 4 May, 2012).

Electronic supplementary material

The online version of this article (10.1186/s12885-017-3641-6) contains supplementary material, which is available to authorized users.

Abstract 5008: The brain microenvironment mediates resistance in luminal breast cancer to PI3K inhibition through HER3 activation

Brain metastases represent a devastating progression of luminal breast cancer. While targeted therapies are often effective systemically, they fail to adequately control brain metastases. In preclinical models that faithfully recapitulate the disparate clinical responses in these microenvironments, we observed that brain metastases evade PI3K inhibition despite efficient drug delivery. In comparison to extracranial disease, there is increased HER3 expression and phosphorylation in the brain lesions. HER3 blockade overcomes the resistance of both HER2-amplified and/or PIK3CA-mutant breast cancer brain metastases to PI3K inhibitors, leading to striking tumor growth delay and significant improvement of mouse survival. Collectively, these data provide a mechanistic basis underlying therapeutic resistance in the brain microenvironment and identify rapidly translatable treatment strategiesfor HER2-amplified and/or PIK3CA-mutant breast cancer brain metastases.

Citation Format: Gino B. Ferraro, David P. Kodack, Vasileios Askoxylakis, Qing Sheng, Mark Badeaux, Shom Goel, Xiaolong Qi, Ram Shankaraiah, Alexander Z. Cao, Rakesh R. Ramjiawan, Divya Bezwada, Bhushankumar Patel, Youngchul Song, Carlotta Costa, Kamila Naxerova, Christina Wong, Jonas Kloepper, Rita Das, Angela Tam, Jantima Tanboon, Dan G. Duda, Ryan C. Miller, Marni B. Siegel, Carey K. Anders, Melinda Sanders, Valeria M. Estrada, Robert Schlegel, Carlos L. Arteaga, Elena Brachtel, Alan Huang, Dai Fukumura, Jeffrey A. Engelman, Rakesh K. Jain. The brain microenvironment mediates resistance in luminal breast cancer to PI3K inhibition through HER3 activation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5008. doi:10.1158/1538-7445.AM2017-5008

Transposable Element Bm1645 is a Source of BmAGO2-associated Small RNAs that affect its expression in Bombyx mori

Background

A transposable element (TE) is a DNA fragment that can change its position within a genome. Transposable elements play important roles in maintaining the stability and diversity of organisms by transposition. Recent studies have shown that approximately half of the genes in Bombyx mori are TEs.

Results

We systematically identified and analyzed the BmAGO2-associated TEs, which exceed 100 in the B. mori genome. Additionally, we also mapped the small RNAs associated with BmAGO2 in B.mori. The transposon Bm1645 is the most abundant TE associated with BmAGO2, and Bm1645-derived small RNAs represent a small RNA pool. We determined the expression patterns of several Bm1645-derived small RNAs by northern blotting, and the results showed there was differential expression of multiple small RNAs in normal and BmNPV-infected BmN cells and silkworms from various developmental stages. We confirmed that four TE-siRNAs could bind to BmAGO2 using EMSA and also validated the recognition sites of these four TE-siRNAs in Bm1645 by dual-luciferase reporter assays. Furthermore, qRT-PCR analysis revealed the overexpression of the four TE-siRNAs could downregulate the expression of Bm1645 in BmN cells, and the transcription of Bm1645 was upregulated by the downregulation of BmAGO2.

Conclusions

Our results suggest Bm1645 functions as a source of small RNAs pool and this pool can produce many BmAGO2-associated small RNAs that regulate TE’s expression.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-017-3598-5) contains supplementary material, which is available to authorized users.

Co-targeting of FAK and MDM2 triggers additive anti-proliferative effects in mesothelioma via a coordinated reactivation of p53

BACKGROUND

Improved mesothelioma patient survival will require development of novel and more effective pharmacological interventions. TP53 genomic mutations are uncommon in mesothelioma, and recent data indicate that p53 remains functional, and therefore is a potential therapeutic target in these cancers. In addition, the tumour suppressor NF2 is inactivated by genomic mechanisms in more than 80% of mesothelioma, causing upregulation of FAK activity. Because FAK is a negative regulator of p53, NF2 regulation of FAK-p53-MDM2 signalling loops were evaluated.

METHODS

Interactions of FAK-p53 or NF2-FAK were evaluated by phosphotyrosine-p53 immunoaffinity purification and tandem mass spectrometry, and p53, FAK, and NF2 immunoprecipitations. Activation and/or expression of FAK, p53, and NF2 were also evaluated in mesotheliomas. Effects of combination MDM2 and FAK inhibitors/shRNAs were assessed by measuring mesothelioma cell viability/growth, expression of cell cycle checkpoints, and cell cycle alterations.

RESULTS

We observed constitutive activation of FAK, a known negative regulator of p53, in each of 10 mesothelioma cell lines and each of nine mesothelioma surgical specimens, and FAK was associated with p53 in five of five mesothelioma cell lines. In four mesotheliomas with wild-type p53, FAK silencing by RNAi induced expression and phosphorylation of p53. However, FAK regulation of mesothelioma proliferation was not restricted to p53-dependent pathways, as demonstrated by immunoblots after FAK knockdown in JMN1B mesothelioma cells, which have mutant/inactivated p53, compared with four mesothelioma cell lines with nonmutant p53. Additive effects were obtained through a coordinated reactivation of p53, by FAK knockdown/inhibition and MDM2 inhibition, as demonstrated by immunoblots, cell viability, and cell-cycle analyses, showing increased p53 expression, apoptosis, anti-proliferative effects, and cell-cycle arrest, as compared with either intervention alone. Our results also indicate that NF2 regulates the interaction of FAK-p53 and MDM2-p53.

CONCLUSIONS

These findings highlight novel therapeutic opportunities in mesothelioma.

Lysine acetylation stabilizes SP2 protein in the silkworm Bombyx mori

Lysine acetylation (Kac) is a vital post-translational modification that plays an important role in many cellular processes in organisms. In the present study, the nutrient storage proteins in hemolymph were first found to be highly acetylated-particularly SP2 protein, which contains 20 potential Kac sites. Further results confirmed that lysine acetylation could stabilize and up-regulate the protein level of anti-apoptosis protein SP2, thereby improving the survival of H2O2-treated BmN cells and suppressing the apoptosis induced by H2O2. The potential mechanism involved in the inhibition of ubiquitin-mediated proteasomal degradation by crosstalk between lysine acetylation and ubiquitination. Our results showed that the increase in the acetylation level by TSA could decrease the ubiquitination and improve the protein level of SP2, indicating that lysine acetylation could influence the SP2 protein level through competition between ubiquitination and the suppression of ubiquitin-mediated proteasomal degradation, thereby stabilizing the protein. SP2 is a major nutrient storage protein from hemolymph for amino acid storage and utilization. The crosstalk between lysine acetylation and ubiquitination of SP2 might imply an important role of lysine acetylation for nutrient storage and utilization in silkworm.

Orexin-A increases the activity of globus pallidus neurons in both normal and parkinsonian rats

Orexin is a member of neuropeptides which was first identified in the hypothalamus. The globus pallidus is a key structure in the basal ganglia, which is involved in both normal motor function and movement disorders. Morphological studies have shown the expression of both OX1 and OX2 receptors in the globus pallidus. Employing single unit extracellular recordings and behavioural tests, the direct in vivo electrophysiological and behavioural effects of orexin-A in the globus pallidus were studied. Micro-pressure administration of orexin-A significantly increased the spontaneous firing rate of pallidal neurons. Correlation analysis revealed a negative correlation between orexin-A induced excitation and the basal firing rate. Furthermore, application of the specific OX1 receptor antagonist, SB-334867, decreased the firing rate of pallidal neurons, suggesting that endogenous orexinergic systems modulate the firing activity of pallidal neurons. Orexin-A increased the excitability of pallidal neurons through both OX1 and OX2 receptors. In 6-hydroxydopamine parkinsonian rats, orexin-A-induced increase in firing rate of pallidal neurons was stronger than that in normal rats. Immunostaining revealed positive OX1 receptor expression in the globus pallidus of both normal and parkinsonian rats. Finally, postural test showed that unilateral microinjection of orexin-A led to contralateral deflection in the presence of systemic haloperidol administration. Further elevated body swing test revealed that pallidal orexin-A and SB-334867 induced contralateral-biased swing and ipsilateral-biased swing respectively. Based on the electrophysiological and behavioural findings of orexin-A in the globus pallidus, the present findings may provide a rationale for the pathogenesis and treatment of Parkinson's disease.

HDACi inhibits liposarcoma via targeting of the MDM2-p53 signaling axis and PTEN, irrespective of p53 mutational status

The MDM2-p53 pathway plays a prominent role in well-differentiated liposarcoma (LPS) pathogenesis. Here, we explore the importance of MDM2 amplification and p53 mutation in LPS independently, to determine whether HDACi are therapeutically useful in LPS. We demonstrated that simultaneous knockdown of MDM2 and p53 in p53-mutant LPS lines resulted in increased apoptosis, anti-proliferative effects, and cell cycle arrest, as compared to either intervention alone. HDACi treatment resulted in the dephosphorylation and depletion of MDM2 and p53 without affecting CDK4 and JUN expression, irrespective of p53 mutational status in MDM2-amplified LPS. In control mesothelioma cell lines, HDACi treatment resulted in down-regulation of p53 in the p53 mutant cell line JMN1B, but resulted in no changes of MDM2 and p53 in two mesothelioma lines with normal MDM2 and wild-type p53. HDACi treatment substantially decreased LPS and mesothelioma proliferation and survival, and was associated with upregulation of PTEN and p21, and inactivation of AKT. Our findings indicate that wild-type p53 depletion by HDACi is MDM2 amplification-dependent. These findings underscore the importance of targeting both MDM2 and p53 in LPS and other cancers harboring p53 mutations. Moreover, the pro-apoptotic and anti-proliferative effect of HDACi warrants further evaluation as a therapeutic strategy in MDM2-amplified LPS.