Ultrahigh-Efficiency Superior Energy Storage in Lead-Free Films with a Simple Composition.

Dielectric capacitors are highly desired in modern electronic devices and power systems to store and recycle electric energy. However, achieving simultaneous high energy density and efficiency remains a challenge. Here, guided by theoretical and phase-field simulations, we are able to achieve a superior comprehensive property of ultrahigh efficiency of 90-94% and high energy density of 85-90 J cm-3 remarkably in strontium titanate (SrTiO3), a linear dielectric of a simple chemical composition, by manipulating local symmetry breaking through introducing Ti/O defects. Atomic-scale characterizations confirm that these Ti/O defects lead to local symmetry breaking and local lattice strains, thus leading to the formation of the isolated ultrafine polar nanoclusters with varying sizes from 2 to 8 nm. These nanoclusters account for both considerable dielectric polarization and negligible polarization hysteresis. The present study opens a new realm of designing high-performance dielectric capacitors utilizing a large family of readily available linear dielectrics with very simple chemistry.

Progress of Clinical Studies Targeting Claudin18.2 for the Treatment of Gastric Cancer.

Claudin18.2 is a tight junction protein, highly selective, generally expressed only in normal gastric mucosal epithelial cells, which can effectively maintain the polarity of epithelial and endothelial cells, thus effectively regulating the permeability and conductance of the paracellular pathway. Abnormal expression of Claudin18.2 can occur in various primary malignant tumors, especially gastrointestinal tumors, and even in metastatic foci. It regulates its expression by activating the aPKC/MAPK/AP-1 pathway, and therefore, the Claudin18.2 protein is a pan-cancer target expressed in primary and metastatic lesions in human cancer types. Zolbetuximab (IMAB362), an antibody specific for Claudin18.2, has been successfully tested in a phase III clinical trial, and the results of the study showed that combining Zolbetuximab with chemotherapy notably extends patients' survival and is expected to be a potential first-line treatment for patients with Claudin18.2(+)/HER-2(-) gastric cancer. Here, we systematically describe the biological properties and oncogenic effects of Claudin18.2, centering on its clinical-pathological aspects and the progress of drug studies in gastric cancer, which can help to further explore its clinical value.

Marine-Derived Sulfated Glycans Inhibit the Interaction of Heparin with Adhesion Proteins of Mycoplasma pneumoniae.

Mycoplasma pneumoniae, a notable pathogen behind respiratory infections, employs specialized proteins to adhere to the respiratory epithelium, an essential process for initiating infection. The role of glycosaminoglycans, especially heparan sulfate, is critical in facilitating pathogen-host interactions, presenting a strategic target for therapeutic intervention. In this study, we assembled a glycan library comprising heparin, its oligosaccharide derivatives, and a variety of marine-derived sulfated glycans to screen the potential inhibitors for the pathogen-host interactions. By using Surface Plasmon Resonance spectroscopy, we evaluated the library's efficacy in inhibiting the interaction between M. pneumoniae adhesion proteins and heparin. Our findings offer a promising avenue for developing novel therapeutic strategies against M. pneumoniae infections.

Biochemical and Genetic Analysis Identify CSLD3 as a beta-1,4-Glucan Synthase That Functions during Plant Cell Wall Synthesis.

In plants, changes in cell size and shape during development fundamentally depend on the ability to synthesize and modify cell wall polysaccharides. The main classes of cell wall polysaccharides produced by terrestrial plants are cellulose, hemicelluloses, and pectins. Members of the cellulose synthase (CESA) and cellulose synthase-like (CSL) families encode glycosyltransferases that synthesize the ß-1,4-linked glycan backbones of cellulose and most hemicellulosic polysaccharides that comprise plant cell walls. Cellulose microfibrils are the major load-bearing component in plant cell walls and are assembled from individual ß-1,4-glucan polymers synthesized by CESA proteins that are organized into multimeric complexes called CESA complexes, in the plant plasma membrane. During distinct modes of polarized cell wall deposition, such as in the tip growth that occurs during the formation of root hairs and pollen tubes or de novo formation of cell plates during plant cytokinesis, newly synthesized cell wall polysaccharides are deposited in a restricted region of the cell. These processes require the activity of members of the CESA-like D subfamily. However, while these CSLD polysaccharide synthases are essential, the nature of the polysaccharides they synthesize has remained elusive. Here, we use a combination of genetic rescue experiments with CSLD-CESA chimeric proteins, in vitro biochemical reconstitution, and supporting computational modeling and simulation, to demonstrate that Arabidopsis (Arabidopsis thaliana) CSLD3 is a UDP-glucose-dependent ß-1,4-glucan synthase that forms protein complexes displaying similar ultrastructural features to those formed by CESA6.

A temperature-sensitive FERONIA mutant allele that alters root hair growth.

In plants, root hairs undergo a highly polarized form of cell expansion called tip-growth, in which cell wall deposition is restricted to the root hair apex. In order to identify essential cellular components that might have been missed in earlier genetic screens, we identified conditional temperature-sensitive (ts) root hair mutants by ethyl methanesulfonate mutagenesis in Arabidopsis thaliana. Here, we describe one of these mutants, feronia-temperature sensitive (fer-ts). Mutant fer-ts seedlings were unaffected at normal temperatures (20°C), but failed to form root hairs at elevated temperatures (30°C). Map based-cloning and whole-genome sequencing revealed that fer-ts resulted from a G41S substitution in the extracellular domain of FERONIA (FER). A functional fluorescent fusion of FER containing the fer-ts mutation localized to plasma membranes, but was subject to enhanced protein turnover at elevated temperatures. While tip-growth was rapidly inhibited by addition of rapid alkalinization factor 1 (RALF1) peptides in both wild-type and fer-ts mutants at normal temperatures, root elongation of fer-ts seedlings was resistant to added RALF1 peptide at elevated temperatures. Additionally, at elevated temperatures fer-ts seedlings displayed altered reactive oxygen species (ROS) accumulation upon auxin treatment and phenocopied constitutive fer mutant responses to a variety of plant hormone treatments. Molecular modeling and sequence comparison with other Catharanthus roseus receptor-like kinase 1L (CrRLK1L) receptor family members revealed that the mutated glycine in fer-ts is highly conserved, but is not located within the recently characterized RALF23 and LORELI-LIKE-GLYCOPROTEIN 2 binding domains, perhaps suggesting that fer-ts phenotypes may not be directly due to loss of binding to RALF1 peptides.

Antibody repertoire sequencing analysis.

High-throughput sequencing for B cell receptor (BCR) repertoire provides useful insights for the adaptive immune system. With the continuous development of the BCR-seq technology, many efforts have been made to develop methods for analyzing the ever-increasing BCR repertoire data. In this review, we comprehensively outline different BCR repertoire library preparation protocols and summarize three major steps of BCR-seq data analysis, i. e., V(D)J sequence annotation, clonal phylogenetic inference, and BCR repertoire profiling and mining. Different from other reviews in this field, we emphasize background intuition and the statistical principle of each method to help biologists better understand it. Finally, we discuss data mining problems for BCR-seq data and with a highlight on recently emerging multiple-sample analysis.

Positive regulation of ataxia-telangiectasia-mutated protein (ATM) by E2F transcription Factor 1 (E2F-1) in cisplatin-resistant nasopharyngeal carcinoma cells.

OBJECTIVE: To explore the mechanism of E2F transcription Factor 1 (E2F-1)-mediated ataxia-telangiectasia-mutated protein (ATM) in cisplatin (DDP)-resistant nasopharyngeal carcinoma (NPC). METHODS: E2F-1 and ATM expression was assessed in DDP-resistant NPC cell lines (CNE2/DDP and HNE1/DDP) and parental cells. Then, DDP-resistant NPC cells were transfected with control shRNA (short hairpin RNA) or E2F-1 shRNAs with or without ATM lentiviral activation particles. The half maximal inhibitory concentration (IC50) was evaluated by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay, and the cell cycle and cell proliferation were measured by flow cytometry and EdU staining, respectively. In addition, the expression of genes and proteins was quantified by quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and western blotting, respectively. RESULTS: Both E2F-1 and ATM expression in DDP-resistant NPC cells was much higher than that in parental cells. E2F-1 shRNA reduced ATM expression in DDP-resistant NPC cells, but ATM overexpression had no significant effect on E2F-1. ATM overexpression enhanced DDP resistance in DDP-resistant NPC cells with increased IC50 values, which was reversed by E2F-1 inhibition. Meanwhile, ATM overexpression resulted in upregulation of ABCA2 and ABCA5 in DDP-resistant NPC cells, induced elevations in the transition of the cells into S-phase, and increased cell proliferation with enhanced expression of cyclin E1, CDK2, and Ki67, which was reversed by E2F-1 shRNAs. CONCLUSION: Downregulation of E2F-1, possibly by regulating ATM, could block the cell cycle in the G1 phase and reduce the proliferation of CNE2/DDP cells, thereby reversing the resistance of human NPC cells to DDP.

Deep Neural Network for Point Sets Based on Local Feature Integration.

The research of object classification and part segmentation is a hot topic in computer vision, robotics, and virtual reality. With the emergence of depth cameras, point clouds have become easier to collect and increasingly important because of their simple and unified structures. Recently, a considerable number of studies have been carried out about deep learning on 3D point clouds. However, data captured directly by sensors from the real-world often encounters severe incomplete sampling problems. The classical network is able to learn deep point set features efficiently, but it is not robust enough when the method suffers from the lack of point clouds. In this work, a novel and general network was proposed, whose effect does not depend on a large amount of point cloud input data. The mutual learning of neighboring points and the fusion between high and low feature layers can better promote the integration of local features so that the network can be more robust. The specific experiments were conducted on the ScanNet and Modelnet40 datasets with 84.5% and 92.8% accuracy, respectively, which proved that our model is comparable or even better than most existing methods for classification and segmentation tasks, and has good local feature integration ability. Particularly, it can still maintain 87.4% accuracy when the number of input points is further reduced to 128. The model proposed has bridged the gap between classical networks and point cloud processing.

Individualized model for predicting COVID-19 deterioration in patients with cancer: A multicenter retrospective study.

The 2019 novel coronavirus has spread rapidly around the world. Cancer patients seem to be more susceptible to infection and disease deterioration, but the factors affecting the deterioration remain unclear. We aimed to develop an individualized model for prediction of coronavirus disease (COVID-19) deterioration in cancer patients. The clinical data of 276 cancer patients diagnosed with COVID-19 in 33 designated hospitals of Hubei, China from December 21, 2019 to March 18, 2020, were collected and randomly divided into a training and a validation cohort by a ratio of 2:1. Cox stepwise regression analysis was carried out to select prognostic factors. The prediction model was developed in the training cohort. The predictive accuracy of the model was quantified by C-index and time-dependent area under the receiver operating characteristic curve (t-AUC). Internal validation was assessed by the validation cohort. Risk stratification based on the model was carried out. Decision curve analysis (DCA) were used to evaluate the clinical usefulness of the model. We found age, cancer type, computed tomography baseline image features (ground glass opacity and consolidation), laboratory findings (lymphocyte count, serum levels of C-reactive protein, aspartate aminotransferase, direct bilirubin, urea, and d-dimer) were significantly associated with symptomatic deterioration. The C-index of the model was 0.755 in the training cohort and 0.779 in the validation cohort. The t-AUC values were above 0.7 within 8 weeks both in the training and validation cohorts. Patients were divided into two risk groups based on the nomogram: low-risk (total points ≤ 9.98) and high-risk (total points > 9.98) group. The Kaplan-Meier deterioration-free survival of COVID-19 curves presented significant discrimination between the two risk groups in both training and validation cohorts. The model indicated good clinical applicability by DCA curves. This study presents an individualized nomogram model to individually predict the possibility of symptomatic deterioration of COVID-19 in patients with cancer.

Metals in Traditional Chinese medicinal materials (TCMM): A systematic review.

Traditional Chinese medicine has become an important pillar of "Healthy China" and the national medical system in recent years. Due to the wide range of raw materials in traditional Chinese medicinal materials (TCMM), the issue of metals has attracted more and more attention. In this paper, a comprehensive review of public reports on metals in TCMM in recent decades was conducted. From a total of 1969 reported articles, a total of 296 research reports on metals in TCMM were screened. The 296 reports involved 255 species in 85 families, with a total of 274 medicinal materials. These TCMM were divided into taproot-type, leaf-type, flower and fruit-type, herba-type, stem-type and bark-type medicinal materials according to the medicinal parts. The content of five metals lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As), chromium (Cr) in these TCMM was noted, and the distribution rules for metals were analyzed. The results showed that: (1) For the distribution of metals in different medicinal parts, Pb was mainly distributed in leaves; Cd was mainly distributed in flowers and fruits, stems and leaves; Hg was mainly distributed in barks; As was mainly distributed in stems; Cr was mainly distributed in stems, flowers and fruits. (2) The areas with the highest risk of metal residues were the Qinghai-Tibet Plateau, south China, and southwest China. (3) Among all types of TCMM, herba-type medicinal materials had the highest risk of metal content. (4) Combined with the pharmacopoeia metal limit standards implemented in 2019, the exceeding rate of Pb in TCMM was the highest, with a maximum value of 37.67%; among the six major types of TCMM, the medicinal materials with the highest exceeding rate were herba-type medicinal materials, among which Hg had the highest exceeding rate of 23.08%; in terms of medicinal parts, the highest exceeding rate of metals was in leaf-type medicinal materials, among which Pb had the highest exceeding rate of 37.67%. On the whole, the situation in regard to metal residues in TCMM was acceptable, but it cannot be ignored. It needed to be paid attention to in the industrialization and management of TCMM.

Crosslinking of CD38 Receptors Triggers Apoptosis of Malignant B Cells.

Recently, we designed an inventive paradigm in nanomedicine-drug-free macromolecular therapeutics (DFMT). The ability of DFMT to induce apoptosis is based on biorecognition at cell surface, and crosslinking of receptors without the participation of low molecular weight drugs. The system is composed of two nanoconjugates: a bispecific engager, antibody or Fab' fragment-morpholino oligonucleotide (MORF1) conjugate; the second nanoconjugate is a multivalent effector, human serum albumin (HSA) decorated with multiple copies of complementary MORF2. Here, we intend to demonstrate that DFMT is a platform that will be effective on other receptors than previously validated CD20. We appraised the impact of daratumumab (DARA)- and isatuximab (ISA)-based DFMT to crosslink CD38 receptors on CD38+ lymphoma (Raji, Daudi) and multiple myeloma cells (RPMI 8226, ANBL-6). The biological properties of DFMTs were determined by flow cytometry, confocal fluorescence microscopy, reactive oxygen species determination, lysosomal enlargement, homotypic cell adhesion, and the hybridization of nanoconjugates. The data revealed that the level of apoptosis induction correlated with CD38 expression, the nanoconjugates meet at the cell surface, mitochondrial signaling pathway is strongly involved, insertion of a flexible spacer in the structure of the macromolecular effector enhances apoptosis, and simultaneous crosslinking of CD38 and CD20 receptors increases apoptosis.

Clinical characteristics, outcomes, and risk factors for mortality in patients with cancer and COVID-19 in Hubei, China: a multicentre, retrospective, cohort study.

BACKGROUND: Patients with cancer are a high-risk population in the COVID-19 pandemic. We aimed to describe clinical characteristics and outcomes of patients with cancer and COVID-19, and examined risk factors for mortality in this population. METHODS: We did a retrospective, multicentre, cohort study of 205 patients with laboratory-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and with a pathological diagnosis of a malignant tumour in nine hospitals within Hubei, China, from Jan 13 to March 18, 2020. All patients were either discharged from hospitals or had died by April 20, 2020. Clinical characteristics, laboratory data, and cancer histories were compared between survivors and non-survivors by use of χ2 test. Risk factors for mortality were identified by univariable and multivariable logistic regression models. FINDINGS: Between Jan 13 and Mar 18, 2020, 205 patients with cancer and laboratory-confirmed SARS-CoV-2 infection were enrolled (median age 63 years [IQR 56-70; range 14-96]; 109 [53%] women). 183 (89%) had solid tumours and 22 (11%) had haematological malignancies. The median duration of follow-up was 68 days (IQR 59-78). The most common solid tumour types were breast (40 [20%] patients), colorectal (28 [14%]), and lung cancer (24 [12%]). 54 (30%) of 182 patients received antitumour therapies within 4 weeks before symptom onset. 30 (15%) of 205 patients were transferred to an intensive care unit and 40 (20%) died during hospital admission. Patients with haematological malignancies had poorer prognoses than did those with solid tumours: nine (41%) of 22 patients with haematological malignancies died versus 31 (17%) of 183 patients with solid tumours (hazard ratio for death 3·28 [95% CI 1·56-6·91]; log rank p=0·0009). Multivariable regression analysis showed that receiving chemotherapy within 4 weeks before symptom onset (odds ratio [OR] 3·51 [95% CI 1·16-10·59]; p=0·026) and male sex (OR 3·86 [95% CI 1·57-9·50]; p=0·0033) were risk factors for death during admission to hospital. INTERPRETATION: Patients with cancer and COVID-19 who were admitted to hospital had a high case-fatality rate. Unfavourable prognostic factors, including receiving chemotherapy within 4 weeks before symptom onset and male sex, might help clinicians to identify patients at high risk of fatal outcomes. FUNDING: National Natural Science Foundation of China.

Inhibition of Immunosuppressive Tumors by Polymer-Assisted Inductions of Immunogenic Cell Death and Multivalent PD-L1 Crosslinking.

Checkpoint blockade immunotherapies harness the host's own immune system to fight cancer, but only work against tumors infiltrated by swarms of pre-existing T cells. Unfortunately, most cancers to date are immune-deserted. Here, we report a polymer-assisted combination of immunogenic chemotherapy and PD-L1 degradation for efficacious treatment in originally non-immunogenic cancer. "Priming" tumors with backbone-degradable polymer-epirubicin conjugates elicits immunogenic cell death and fosters tumor-specific CD8+ T cell response. Sequential treatment with a multivalent polymer-peptide antagonist to PD-L1 overcomes adaptive PD-L1 enrichment following chemotherapy, biases the recycling of PD-L1 to lysosome degradation via surface receptor crosslinking, and produces prolonged elimination of PD-L1 rather than the transient blocking afforded by standard anti-PD-L1 antibodies. Together, these findings established the polymer-facilitated tumor targeting of immunogenic drugs and surface crosslinking of PD-L1 as a potential new therapeutic strategy to propagate a long-term antitumor immunity, which might broaden the application of immunotherapy to immunosuppressive cancers.

High-coverage SARS-CoV-2 genome sequences acquired by target capture sequencing.

In this study, we designed a set of SARS-CoV-2 enrichment probes to increase the capacity for sequence-based virus detection and obtain the comprehensive genome sequence at the same time. This universal SARS-CoV-2 enrichment probe set contains 502 120 nt single-stranded DNA biotin-labeled probes designed based on all available SARS-CoV-2 viral sequences and it can be used to enrich for SARS-CoV-2 sequences without prior knowledge of type or subtype. Following the CDC health and safety guidelines, marked enrichment was demonstrated in a virus strain sample from cell culture, three nasopharyngeal swab samples (cycle threshold [Ct ] values: 32.36, 36.72, and 38.44) from patients diagnosed with COVID-19 (positive control) and four throat swab samples from patients without COVID-19 (negative controls), respectively. Moreover, based on these high-quality sequences, we discuss the heterozygosity and viral expression during coronavirus replication and its phylogenetic relationship with other selected high-quality samples from the Genome Variation Map. Therefore, this universal SARS-CoV-2 enrichment probe system can capture and enrich SARS-CoV-2 viral sequences selectively and effectively in different samples, especially clinical swab samples with a relatively low concentration of viral particles.

Arabidopsis CSLD5 Functions in Cell Plate Formation in a Cell Cycle-Dependent Manner.

In plants, the presence of a load-bearing cell wall presents unique challenges during cell division. Unlike other eukaryotes, which undergo contractile cytokinesis upon completion of mitosis, plants instead synthesize and assemble a new dividing cell wall to separate newly formed daughter cells. Here, we mine transcriptome data from individual cell types in the Arabidopsis thaliana stomatal lineage and identify CSLD5, a member of the Cellulose Synthase Like-D family, as a cell wall biosynthesis enzyme uniquely enriched in rapidly dividing cell populations. We further show that CSLD5 is a direct target of SPEECHLESS, the master transcriptional regulator of these divisions during stomatal development. Using a combination of genetic analysis and in vivo localization of fluorescently tagged fusion proteins, we show that CSLD5 preferentially accumulates in dividing plant cells where it participates in the construction of newly forming cell plates. We show that CSLD5 is an unstable protein that is rapidly degraded upon completion of cell division and that the protein turnover characteristics of CSLD5 are altered in ccs52a2 mutants, indicating that CSLD5 turnover may be regulated by a cell cycle-associated E3-ubiquitin ligase, the anaphase-promoting complex.

Identification of Potentially Functional CircRNA-miRNA-mRNA Regulatory Network in Gastric Carcinoma using Bioinformatics Analysis.

BACKGROUND As all we know, gastric cancer (GC) is a highly aggressive disease. Recently, circular RNA (circRNA) was found to play a vital role in regulation of GC. Some circRNAs could regulate messenger RNA (mRNA) expression by functioning as a microRNA (miRNA) sponge. Nevertheless, the circRNA-miRNA-mRNA regulatory network involved GC rarely has been explored and researched. MATERIAL AND METHODS All the differentially expressed circRNAs, miRNAs, and mRNA were derived from Gene Expression Omnibus (GEO) microarray data (GSE78092, GSE89143, GSE93415, and GSE54129). GC level 3 miRNA-sequencing data and clinical information were downloaded from The Cancer Genome Atlas (TCGA) database. Furthermore, a circRNA-miRNA-mRNA regulatory network was constructed by Cytoscape (version 3.6.1). Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway revealed the functions and signaling pathways associated with these target genes. Hub genes of protein-protein interaction (PPI) network were identified by STRING database and cytoHubba. RESULTS The regulatory network consists of 3 circRNAs, 22 miRNAs, and 128 mRNAs. Only 3 miRNAs of the network were consistent with the expression of TCGA and were associated with some clinical features. The results of the functional analysis of 128 mRNAs showed that GO analysis and KEGG pathways of inclusion criteria were 49 and 24, respectively. PPI network and Cytoscape showed that the top 10 hub genes were MYC, CTGF, TGFBR2, TGFBR1, SERPINE1, KRAS, ZEB1, THBS1, CDK6, and TNS1; 4 of which were verified by GEPIA based on TCGA. Highly expressed SERPINE1 had a poor OS (over survival) and DFS (disease-free survival), and TGFBR1 expression increased along with the increase of clinical stages. CONCLUSIONS This study looked at a circRNA-miRNA-mRNA regulatory network associated with GC and explored the potential functions of mRNA in the network, then identified a new molecular marker for prediction, prognosis, and therapeutic targets for clinical patients.

Drug-free macromolecular therapeutics induce apoptosis in cells isolated from patients with B cell malignancies with enhanced apoptosis induction by pretreatment with gemcitabine.

Drug-free macromolecular therapeutics (DFMT) is a new paradigm for the treatment of B cell malignancies. Apoptosis is initiated by the biorecognition of complementary oligonucleotide motifs at the cell surface resulting in crosslinking of CD20 receptors. DMFT is composed from two nanoconjugates: 1) bispecific engager, Fab'-MORF1 (anti-CD20 Fab' fragment conjugated with morpholino oligonucleotide), and 2) a crosslinking (effector) component P-(MORF2)X (N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer grafted with multiple copies of complementary morpholino oligonucleotide). We evaluated this concept in 44 samples isolated from patients diagnosed with various subtypes of B cell malignancies. Apoptosis was observed in 65.9% of the samples tested. Pretreatment of cells with gemcitabine (GEM) or polymer-gemcitabine conjugate (2P-GEM) enhanced CD20 expression levels thus increasing apoptosis induced by DFMT. These positive results demonstrated that DFMT has remarkable therapeutic potential in various subtypes of B cell malignancies.

Phosphorylation of SPOROCYTELESS/NOZZLE by the MPK3/6 Kinase Is Required for Anther Development.

Germ cells are indispensable carriers of genetic information from one generation to the next. In contrast to the well-understood process in animals, information on the mechanism of germ cell initiation in plants is very limited. SPOROCYTELESS/NOZZLE was previously identified as an essential regulator of diploid germ cell (archesporial cell) differentiation in the stamens and ovules of Arabidopsis (Arabidopsis thaliana). Although SPOROCYTELESS (SPL) transcription is activated by the floral organ identity regulator AGAMOUS and epigenetically regulated by SET DOMAIN GROUP2, little is known about the regulation of the SPL protein. Here, we report that the protein kinases MPK3 and MPK6 can both interact with SPL in vitro and in vivo and can phosphorylate the SPL protein in vitro. In addition, phosphorylation of the SPL protein by MPK3/6 is required for SPL function in the Arabidopsis anther, as measured by its effect on archesporial cell differentiation. We further demonstrate that phosphorylation enhances SPL protein stability. This work not only uncovers the importance of SPL phosphorylation for its regulatory role in Arabidopsis anther development, but also supports the hypothesis that the regulation of precise spatiotemporal patterning of germ cell initiation and that differentiation is achieved progressively through multiple levels of regulation, including transcriptional and posttranslational modification.

Effect of RSK4 on biological characteristics of colorectal cancer.

BACKGROUND: This study aimed to investigate the expression of P90 Ribosomal Protein S6 kinase 4 (RSK4) in colorectal cancer cells and its biological function. METHODS: We selected early SW480 and HCT116 colorectal cancer cell lines, using Lipofectamine™ 2000 transfection reagent carrying RSK4 gene transfected into cells to establish the colorectal cancer cell lines with high expression of RSK4. RT-PCR and western blot (WB) analysis confirmed RSK4 expression in SW480 and HCT116 cancer cell lines. We used methylthiazoltetrazolium (MTT) assay and flow cytometry to detect the proliferation of colorectal cancer cells. After transfection of RSK4, the effect of RSK4 on the RNA levels associated with epithelial-mesenchymal transition (EMT) of colorectal cancer cells was analyzed by real-time fluorescence quantitative PCR and the expression of EMT-related protein was detected by WB analysis. RESULTS: After transfection of RSK4 overexpression, the MTT assay detected that RSK4 could significantly inhibit the growth of colorectal cancer cells in vitro; flow cytometry detected that S-phase cells decreased significantly, and G0/1 cells increased significantly (P < 0.05). The invasion ability of SW480 and HCT116 cells transfected with RSK4 was markedly lower than that in the control group, and the difference was statistically significant (P < 0.05). Fluorescent quantitative PCR and WB analysis showed that the expression of EMT-associated molecular E-cadherin was remarkably increased and the expression of Snail was significantly decreased (P < 0.01). CONCLUSION: RSK4 gene in colorectal cancer cell lines with low expression of RSK4 after transfection can inhibit the growth and invasion of tumor cells. RSK4 gene may inhibit EMT and inhibit metastasis of colorectal cancer cells, may be a potential tumor suppressor gene and inhibit tumor distant metastasis, and may provide the biological basis for new therapeutic targets.

The Light at the End of the Tunnel-Second Generation HPMA Conjugates for Cancer Treatment.

It is almost four decades since N-(2-hydroxypropyl)methacrylamide (HPMA) - based copolymers arose as drug carriers. Although fundamentals have been established and significant advantages have been proved, the commercialization of this platform technology was hampered due to modest outcome of clinical trial initiated with PK1, the symbol of first generation polymer-drug conjugates. In this review, we illustrate the exciting progress and approaches offered by more effective 2nd generation HPMA-based polymer-drug conjugates in cancer treatment. For example, a new synthetic strategy endorses inert HPMA polymer with biodegradability, which permitted to prepare high molecular weight HPMA-drug conjugates with simple linear architecture while maintaining good biocompatibility. As expected, extended long-circulating pharmacokinetics and enhanced antitumor activities were achieved in several preclinical investigations. In addition, greater inhibition of tumor growth in combination regimes exhibits the remarkable capability and flexibility of HPMA-based macromolecular therapeutics. The review also discusses the main challenges and strategies for further translation development of 2nd generation HPMA-based polymer-drug conjugates.