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Triple-negative breast cancer (TNBC) is a malignant tumor without specific therapeutic targets and a poor prognosis. Chemotherapy is currently the first-line therapeutic option for TNBC. However, due to the heterogeneity of TNBC, not all of TNBC patients are responsive to chemotherapeutic agents. Therefore, the demand for new targeted agents is critical. β -tubulin isotype III (Tubb3) is a prognostic factor associated with cancer progression, including breast cancer, and targeting Tubb3 may lead to improve TNBC disease control. Shikonin, the active compound in the roots of Lithospermun erythrorhizon suppresses the growth of various types of tumors, and its efficacy can be improved by altering its chemical structure. In this work, the anti-TNBC effect of a shikonin derivative (PMMB276) was investigated, and its mechanism was also investigated. This study combines flow cytometry, immunofluorescence staining, immunoblotting, immunoprecipitation, siRNA silencing, and the iTRAQ proteomics assay to analyze the inhibition potential of PMMB276 on TNBC. In vivo study was performed, Balb/c female murine models with or without the small molecule treatments. Herein, we screened 300 in-house synthesized analogs of shikonin against TNBC and identified a novel small molecule, PMMB276; it suppressed cell proliferation, induced apoptosis, and arrested the cell cycle at the G2/M phase, suggesting that it could have a tumor suppressive role in TNBC. Tubb3 was identified as the target of PMMB276 using proteomic and biological activity analyses. Meanwhile, PMMB276 regulated microtubule dynamics in vitro by inducing microtubule depolymerization and it could act as a tubulin stabilizer by a different process than that of paclitaxel. Moreover, suppressing or inhibiting Tubb3 with PMMB276 reduced the growth of breast cancer in an experimental mouse model, indicating that Tubb3 plays a significant role in TNBC progression. The findings support the therapeutic potential of PMMB276, a Tubb3 inhibitor, as a treatment for TNBC. Our findings might serve as a foundation for the utilization of shikonin and its derivatives in the development of anti-TNBC. A small novel molecule, i.e., α-lipoic acyl shikonin, modified form of a natural product (shikonin), acts as a novel inhibitor of Tubb3. [Display omitted] [ABSTRACT FROM AUTHOR]

Plant roots continuously influence the rhizosphere, which also serves as a recruitment site for microorganisms with desirable functions. The development of genetically engineered (GE) crop varieties has offered unparalleled yield advantages. However, in-depth research on the effects of GE crops on the rhizosphere microbiome is currently insufficient. We used a triple-transgenic soybean cultivar (JD606) that is resistant to insects, glyphosate, and drought, along with its control, ZP661, and JD606 treated with glyphosate (JD606G). Using 16S and ITS rDNA sequencing, their effects on the taxonomy and function of the bacterial and fungal communities in the rhizosphere, surrounding, and bulk soil compartment niches were determined. Alpha diversity demonstrated a strong influence of JD606 and JD606G on bacterial Shannon diversity. Both treatments significantly altered the soil's pH and nitrogen content. Beta diversity identified the soil compartment niche as a key factor with a significant probability of influencing the bacterial and fungal communities associated with soybeans. Further analysis showed that the rhizosphere effect had a considerable impact on bacterial communities in JD606 and JD606G soils but not on fungal communities. Microbacterium , Bradyrhizobium , and Chryseobacterium were found as key rhizobacterial nodes. In addition, the LEfSe analysis identified biomarker taxa with plant-beneficial attributes, demonstrating rhizosphere-driven microbial recruitment. FUNGuild, Bugbase, and FAPROTAX functional predictions showed that ZP661 soils had more plant pathogen-associated microbes, while JD606 and JD606G soils had more stress-tolerance, nitrogen, and carbon cycle-related microbes. Bacterial rhizosphere networks had more intricate topologies than fungal networks. Furthermore, correlation analysis revealed that the bacteria and fungi with higher abundances exhibited varying degrees of positive and negative correlations. Our findings shed new light on the niche partitioning of bacterial and fungal communities in soil. It also indicates that following triple-transgenic soybean cultivation and glyphosate application, plant roots recruit microbes with beneficial taxonomic and functional traits in the rhizosphere. [Display omitted] • The triple-transgenic soybean and glyphosate shaped the rhizosphere bacterial community. • Soil compartment niche had a substantial impact on the bacterial and fungal community assembly. • Rhizosphere effect resulted in the enrichment of beneficial bacterial and fungal taxa. • LEfSe and network analyses revealed rhizosphere-driven microbial recruitment. • Fungal networks were relatively less dense and more robust than bacterial networks. [ABSTRACT FROM AUTHOR]

Since the lack of targeted treatment, triple-negative breast cancer (TNBC) has poor outcomes. Histone deacetylase inhibitors (HDACi) blocking the activity of specific HDACs have emerged as cancer therapeutic agents. However, the therapeutic efficiency is still not satisfactory for patients with solid tumor. We thus performed screening for the synergistic agents of Vorinostat (SAHA). The resulting candidate Simvastatin was obtained. The efficacy and mechanism of combination have been studied in TNBC cells. The synergism of SAHA and Simvastatin was evaluated by IC 50 of proliferation and combination index (CI). The antitumor activities of combination were further evaluated in TNBC cells. The pro-apoptotic effects were determined by flow cytometry and Western blot. Autophagosome-lysosome fusion was monitored using confocal microscope. The underlying mechanism was further studied by over-expressing of wild-type or inactive (C205S/C207S) Rab7 in compounds treated cells. The in vivo efficacy was also evaluated in mice. The combination of SAHA and Simvastatin had potent synergism in apoptosis of TNBC cells. It exerted pro-apoptosis effect by compromising the fusion between autophagosome and lysosome. Over-expressing of wild-type, but not inactive Rab7 rescued cells from apoptosis induced by the combinatory treatments. Mevalonate supplementation also decreased the combinatory treatment-induced apoptosis. These results indicate that the combinatory treatment enhances the apoptosis of TNBC cells by interrupting Rab7 prenylation and obstructing autophagosome-lysosome fusion. Combination between SAHA and Simvastatin could also significantly decrease the tumor growth in xenografted mice by inducing apoptosis and inhibiting Rab7 prenylation. Rab7 is a potential target for the combined effects of Simvastatin and SAHA. [ABSTRACT FROM AUTHOR]

Colorectal cancer is a common malignancy and the second leading cause of cancer-related death. Emerging evidence suggests that the Wnt/β-catenin pathway has a significant role in cancer development. Shikonin is one of the main bioactive components of the plant, Lithospermum erythrorhizon, which possesses various biological properties. In this study, we identified a shikonin derivative, E5, as a novel suppressor of colorectal carcinoma that acted by inhibiting cell proliferation and migration, and promoting apoptosis. Mechanistically, the drug activated caspase-dependent pathways, negatively regulating the Wnt/β-catenin pathway, and inhibited epithelial–mesenchymal transition. The findings suggest the potential of β-catenin as a molecular target in colon carcinoma and propose E5 as a promising therapeutic strategy for targeting Wnt/β-catenin [Display omitted] ● A novel thioether shikonin derivative (E5), modified form of shikonin, acts as a novel inhibitor of β-catenin. ● E5 suppressed cancer cell proliferation and migration and promoted cell apoptosis via caspase-dependent pathways. ● E5 can be a drug candidate and has the potential to inhibit Wnt/β-catenin signaling pathway in the colon carcinoma. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Cancer cells are continuously challenged by adverse environmental stress and adopt diverse strategies to survive. Hsp70 plays pivotal roles in invasion, migration, drug resistance, and the survival of tumor cells. Hsp70 functions as molecular chaperone to protect tumor cells from stress-induced cell death. Hsp70 acetylation alters its chaperone activity in cell death pathways, but its relevance in the process of cell death and the underlying mechanisms involved are not well understood. In this study, we demonstrated that vincristine induces mitophagy via the disruption of Hsp70 binding with Sirt2, leading to Hsp70 acetylation at K126 and elevated sequestration of Bcl2 by Hsp70 for autophagosome creation. Acetylation at K126 significantly changes the physiological function of Hsp70 compared to acetylation at other sites. It also attenuates the protein folding and renaturation function of Hsp70 by altering the binding co-chaperones. In addition, acetylation at K126 inhibits Hsp70-mediated tumor cell invasion and migration, and the binding of Hsp70 to AIF1 and Apaf1 for promoting mitochondrial-mediated apoptosis. In conclusion, this study describes the molecular mechanism of vincristine induction of cell apoptosis and mitophagy via ablation of Sirt2 induced Hsp70 acetylation at K126 in MDA-MB-231 cells. [ABSTRACT FROM AUTHOR]

This study aimed to examine the antiviral effects of shikonin ester ((R)-1-(5, 8-dihydroxy-1,4-dioxo-1,4-dihydronaphthalen-2-yl)-4-methylpent-3-en-1-yl3-(1H- indol-3-yl) propanoate (PMM-034) against influenza A (H1N1) virus. We investigated PMM-034 anti-H1N1 activity and its effect on caspase 3 gene expression during cellular apoptosis after influenza virus infection in vitro. Neuraminidase (NA) inhibition was assessed in comparison with oseltamivir in the influenza virus standard strains A/PR/8/34 to understand the viral mechanism. MDCK and A549 cells were used to investigate influenza viral infection and the structure-activity relationship between PMM-034 and NA was evaluated by pharmacophore-based docking modeling. The production of viral protein was tested by western blot. A/PR/8/34 induced cell inhibition but this was reduced by PMM-034 to 16 μg/mL and this showed a selective index of 10 mM. PMM-034 inhibited NA in a dose dependent manner, similar to oseltamivir inhibition. A sharp decrease in viral nucleocapsid protein mRNA was observed in infected cells after treatment with PMM-034. Apoptosis of infected A459 cells was inhibited by PMM-034 with decreased caspase 3 levels. ARG 118, ARG 152, ARG 371 and GLU 227 in the binding pocket of NA bound to PMM-034 in the docking model. Taken together, these results suggest PMM-034 shikonin ester blocked H1N1 infection and might be a potential anti-H1N1 drug. [ABSTRACT FROM AUTHOR]

Pyruvate kinase 2 (PKM2) and pyruvate dehydrogenase kinase 1 (PDK1) are two key enzymes in tumor glucose metabolism pathway that not only promote tumor growth and proliferation through accelerating aerobic glycolysis, but also contribute to drug resistance of non-small cell lung cancer (NSCLC). Considering that targeting PKM2 or PDK1 alone seems insufficient to remodel abnormal glucose metabolism to achieve significant antitumor activity, we proposed a "two-step approach" that regulates PKM2 and PDK1 synchronously. Firstly, we found that the combination of ML265 (PKM2 activator) and AZD7545 (PDK1 inhibitor) could synergistically inhibit proliferation and induce apoptosis in H1299 cells. Base on this, we designed a series of novel shikonin (SK) thioether derivatives as PKM2/PDK1 dual-target agents, among which the most potent compound E5 featuring a 2-methyl substitution on the benzene ring exerted significantly increased inhibitory activity toward EGFR mutant NSCLC cell H1975 (IC 50 = 1.51 μmol/L), which was 3 and 17-fold more active than the lead compound SK (IC 50 = 4.56 μmol/L) and the positive control gefitinib (IC 50 = 25.56 μmol/L), respectively. Additionally, E5 also showed good anti-tumor activity in xenografted mouse models, with significantly lower toxicity side effects than SK. Moreover, E5 also inhibited the entry of PKM2 into nucleus to regulate the transcriptional activation of oncogenes, thus restoring the sensitivity of H1975 cell to gefitinib. Collectively, these data demonstrate that E5 , a dual inhibitor of PKM2/PDK1, may be a promising adjunct to gefitinib in the treatment of EGFR-TKIs resistant NSCLC, deserving further investigation. [Display omitted] • A synergistic effect of PKM2 activation and PDK1 inhibition was first demonstrated. • A series of PKM2/PDK1 dual-target shikonin thioether derivatives were developed. • The most active compound E5 significantly inhibit tumor growth in vitro and in vivo. • The most active compound E5 enhance the sensitivity of H1975 cells to gefitinib. [ABSTRACT FROM AUTHOR]

PDK1 is one of the key enzymes in the glucose metabolism pathway, which is abnormally high expressed in breast cancer tissues and can promote tumor proliferation and metastasis. PDK1 and the PDHC/PDK axis are important targets for regulating glucose metabolism and anti-tumor activity. In this study, we evaluated the anti-tumor activities of a series of semi-synthesized shikonin (SK) derivatives against human breast cancer cells. The anti-proliferation activity of SK derivatives against human breast cancer cell lines was tested by CCK-8 and EdU assay. Flow cytometry was utilized to evaluate cell apoptosis, reactive oxygen species and cell cycle distribution. Cell migration ability was determined by wound healing and trans-well assay. PDK1 targeting effect was confirmed by western bolting, molecular docking, bio-layer interferometry and PDK1 enzyme activity assay. Nude-mouse transplanted tumor model was used to evaluate their anti-tumor effect in vivo. Findings revealed that SK derivatives had good anti-proliferation ability against MDA-MB-231 cell. They induced cell apoptosis by regulating the mitochondrial apoptosis and death receptor pathway. They also inhibited cell migration by suppressing EMT progression. Molecular docking, PDK1 affinity and enzyme activity demonstrated their PDK1 targeting. In vivo antitumor experiment showed that E2 could significantly inhibit tumor growth with lower side-effect on mice than SK. In conclusion, the novel SK derivatives E2 and E5 inhibited tumor glycolysis by targeting PDK1 and ultimately induced apoptosis. Our data demonstrated that E2 would be a good lead compound for the treatment of human TNBC as a novel PDK1 inhibitor. [ABSTRACT FROM AUTHOR]

PMMB-302 has an effect on the expression of apoptosis-related proteins such as Bcl2, Bcl-XL, caspase-9, caspase3 and FADD. Moreover, PMMB-302 inhibited expression of telomerase core proteins, dyskerin and NHP2, and telomerase reverse transcriptase RNA. These results suggested that PMMB-302 has tumor suppressive roles in lung cancer cells. [Display omitted] • A small novel molecule modified form of a natural product (shikonin), acts as a novel inhibitor of telomerase. • The small molecule suppresses cancer cell proliferation in vitro via inducing apoptosis and arresting cell cycle at G2/M phase. • This small molecule induces apoptosis in A549 cells through the mitochondrial and death receptor pathways. In this study, a series of novel shikonin N -benzyl matrinic acid ester derivatives (PMMB-299–PMMB-310) were synthesized and tested for their ability to inhibit the proliferation of cancer cells. Compared with shikonin and matrine, some of the ester derivatives were found to exhibit better anti-proliferative activity against seven different cancer cell lines, with less cytotoxicity toward non-cancerous cells. The strongest anti-proliferative activity was exhibited by PMMB-302, which had an IC 50 value of 2.71 μM against A549 cells. The compound caused cell cycle arrest in the G2/M phase and induced apoptosis. Effects on the expression of apoptosis-related molecules such as Bcl2, Bcl-XL, caspase-3, caspase-9 and FADD suggested that PMMB-302 has tumor suppressive roles in lung cancer cells. In addition, PMMB-302 inhibited expression of telomerase core proteins, dyskerin and NHP2, and telomerase reverse transcriptase RNA. Moreover, molecular docking of PMMB-302 was subsequently conducted to determine the probable binding mode with telomerase. Taken together, the results indicate that PMMB-302 acts as a tumor suppressor in lung cancer cells by negatively regulating telomerase expression. [ABSTRACT FROM AUTHOR]

The target of product attributes prediction is to complete the characteristics set for defining a particular product. Most of the existing methods treat the product attributes prediction as a Named-Entity Recognition (NER) problem from the products' affiliated data, such as product title and introduction. However, in a large number of industrial applications of Alibaba, we found that the existing methods are good at concrete attributes extraction (e.g., color, size) but short of abstract attributes extraction (e.g., applicable event). Moreover, these abstract attributes are usually not easy to extract from the products' affiliated data. In this paper, we propose a novel heterogeneous s tar graph a ttention n etwork called "SAN", which incorporates the advantages of multiple information in the e-commerce scene to predict the abstract attributes of products. Specifically, we model the customer interactive behaviors, product title and concrete attributes of a product as a star graph. Then, we extract the node features, node types and graph structure information from the heterogeneous star graph network which consists of n star graphs. By leveraging the parallel multiple attention mechanism, SAN can aggregate features and learn weights of nodes for product representation and abstract attribute prediction. Extensive experimental results of a real-world e-commerce dataset have demonstrated that SAN outperforms state-of-the-art methods significantly for product attributes prediction. These series of solutions are already planned for use in the applications of Alibaba. [ABSTRACT FROM AUTHOR]

• SbNAC2 can be induced by various abiotic stresses. • Silencing of SbNAC2 leads to compromised drought tolerance of sorghum seedlings. • SbNAC2 can directly induce SbAP37 , a stress-response gene, to enhance the stress tolerance of sorghum. • Heterologous expression of SbNAC2 in Arabidopsis and rice enhanced the stress tolerance of the transgenic plants. Major abiotic stresses such as drought and salinity affect the growth and yield of crops. NAC (NAM, ATAF1/2, and CUC2) is a plant-specific gene family that has been demonstrated to contribute to responses and adaption to abiotic stress in plants. The specific NAC transcription factors (TFs) that play important roles in the response to abiotic stress in sorghum are unknown. Here, we characterized a sorghum TF, SbNAC2, that can be strongly induced by abiotic stresses, including polyethylene glycol (PEG)-simulated dehydration stress treatment, salt treatment, and 4 °C chilling. Knockdown of SbNAC2 in sorghum seedlings by virus-induced gene silencing (VIGS) weakened the drought tolerance of plants. Heterologous overexpression of SbNAC2 in Arabidopsis and rice can induce plant antioxidant enzyme activity under abiotic stress conditions. Furthermore, SbNAC2 directly activates the expression of a stress responsive AP2/ERF type TF gene, SbAP37 , by binding to the TTNCGTA motif of its promoter. These results indicate that SbNAC2 functions as a potentially important regulator in response to abiotic stresses and that it may possibly be used for molecular breeding to enhance crop yields under adverse environmental conditions. [ABSTRACT FROM AUTHOR]

Abstract: Aluminum (Al) is one of the limiting factors for crop production in acidic soil. We aimed to demonstrate how the rhizosphere diazotrophic community responds to two contrasting soybean genotypes, BX10 (Al-tolerant) and BD2 (Al-sensitive), under Al stress at different growth stages. The diversity and abundance of nifH gene in the rhizosphere soils were assessed by denaturing gradient gel electrophoresis (DGGE) and real-time PCR. The results indicated that there were differences in the community structure between BX10 and BD2 at three sampling stages, respectively. Phylogenetic analyses revealed that 3 and 16 non-identical sequences were responsive to BX10 and BD2, respectively, during the whole growth periods. Parts of sequences responsive to BD2 were affiliated with Rhizobium sp. and Azospirillum brasilense, which have the potential to promote plant growth. Dominant diazotrophs varied in different growth stages of both soybean genotypes. Higher nifH abundance was observed in BD2 at seedling stage, whereas that was detected in BX10 at flowering and maturity stages. The diazotrophic community is sensitive and responds differentially to different soybean genotypes adapted to Al stress, as demonstrated by the increased quantity of diazotrophs in BX10 and the stimulation of beneficial diazotrophic bacteria in BD2. [Copyright &y& Elsevier]

Abstract: We report the design and characterization of a microarray with 46 short virus-specific oligonucleotides for detecting influenza A virus of 5 subtypes: H1N1, H1N2, H3N2, H5N1, and H9N2. A unique combination of 3 specific modifications was introduced into the microarray assay: (1) short probes of 19 to 27 nucleotides, (2) simple amplification of full-length hemagglutinin and neuraminidase cDNAs with universal primers, and (3) Klenow-mediated labeling and further amplification of the samples before hybridization. The assay correctly and specifically detected and subtyped 11 different influenza A isolates from human, avian, and swine species representing the 5 subtypes. When tested with 225 clinical samples, 20 were detected to be positive using our microarray-based assay, whereas only 10 were positive by the conventional culture method. The entire analysis was completed within 7 h. Thus, these modifications result in a specific, sensitive, and rapid microarray assay and may be used for constructing microarrays for the detection of all influenza subtypes and strains. [Copyright &y& Elsevier]

Amphiphilic block copolymers, poly(caprolactone)–poly(ethylene glycol)–poly(lactide) (PCELA), were synthesized by ring opening polymerization of caprolactone and lactide initiated with the hydroxyl groups of poly(ethylene glycol) (PEG). These copolymers could form micelle-like nanoparticles due to their amphiphilic characteristic. From the observation of transmission electron microscopy (TEM), the nanoparticles exhibited a regular spherical shape with core-shell structure. The critical micelle concentrations (CMC) of these nanoparticles in water were decreased as molecular weight of PEG decreased. The particle sizes obtained by dynamic light scattering of these nanoparticles were in the range of 100–200 nm, and increased as the hydrophobic property of the nanoparticles increased. Nimodipine as a model drug was loaded in these nanoparticles to investigate the drug release behavior. It was found that the chemical composition of the nanoparticles was a key factor in controlling nanoparticle size, nanoparticle yields, drug-entrapment efficiency, and drug release behavior. When the PEG content is about 2% (wt), the release profile of PCELA nanoparticles appeared to follow zero-order kinetics. [Copyright &y& Elsevier]

• SbWRKY30 could respond to various abiotic stresses and phytohormones. • Heterologous overexpression of SbWRKY30 enhances plant drought tolerance in Arabidopsis and rice. • SbWRKY30 confers plant drought stress tolerance by affecting the root architecture. • SbWRKY30 protects plant cells from the damage of active oxygen species by improving ROS scavenging capability. • SbWRKY30 enhances drought stress by directly activating SbRD19 in sorghum. WRKY transcription factors have been suggested to play important roles in response and adaptation to drought stress. However, how sorghum WRKY transcription factors function in drought stress is still unclear. Here, we identify a WRKY transcription factor of sorghum, SbWRKY30, which is induced significantly by drought stress. SbWRKY30 is mainly expressed in sorghum taproot and leaf. SbWRKY30 has transcriptional activation activity and functions in the nucleus. Heterologous expression of SbWRKY30 confers tolerance to drought stress in Arabidopsis (Arabidopsis thaliana) and rice by affecting root architecture. In addition, SbWRKY30 transgenic Arabidopsis and rice plants have higher proline contents and SOD, POD, and CAT activities but lower MDA contents than wild-type plants after drought stress. As a homologous gene of the drought stress-responsive gene RD19 of Arabidopsis , SbRD19 overexpression in Arabidopsis improved the drought tolerance of plants relative to wild-type plants. Further analysis demonstrated that SbWRKY30 could induce SbRD19 expression through binding to the W-box element in the promoter of SbRD19. These results suggest that SbWRKY30 functions as a positive regulator in response to drought stress. Therefore, SbWRKY30 may serve as a promising candidate gene for molecular breeding to generate drought-tolerant crops. [ABSTRACT FROM AUTHOR]