CBLC inhibits the proliferation and metastasis of breast cancer cells via ubiquitination and degradation of CTTN.

The E3 ubiquitin ligase is an important regulator of cell signaling and proteostasis and is tightly controlled in many diseases, including cancer. Our study aimed to investigate the biological role of the E3 ubiquitin ligase CBLC in breast cancer and elucidate the specific mechanistic network underlying CBLC-mediated target substrate degradation, cell proliferation and metastasis. Here, we showed that CBLC expression was higher in breast cancer tissues and cells than that in normal tissues and cells. Higher expression of CBLC predicted a better prognosis for breast cancer patients. CBLC inhibited the proliferation, migration and invasion of breast cancer cells. Co-IP and immunofluorescence co-localization assays demonstrated that CBLC interacted with CTTN in the cytoplasm. CBLC promoted the degradation of CTTN through the ubiquitin-proteasome pathway without affecting its mRNA level. The inhibitory effect of CBLC on breast cancer cell proliferation, migration and invasion could partly be reversed by CTTN. Taken together, our study clarified the biological role of CBLC as a tumor suppressor and discovered its functional substrate, providing a molecular basis for CBLC/CTTN as a potential therapeutic target in breast cancer.

Glutamate Ionotropic Receptor Kainate Type Subunit 3 (GRIK3) promotes epithelial-mesenchymal transition in breast cancer cells by regulating SPDEF/CDH1 signaling.

Glutamate Ionotropic Receptor Kainate Type Subunit 3 (GRIK3) is an important excitatory neurotransmitter receptor that plays a significant role in various neurodegenerative diseases. However, the biological functions of GRIK3 in malignancies are largely unknown because of limited related studies. Here, we primarily reported that the expression of GRIK3 was higher in breast cancer tissues than in adjacent noncancerous tissues. GRIK3 expression was also positively correlated with the prognosis of patients with breast cancer. GRIK3 promoted the proliferation and migration abilities of breast cancer cells and enhanced the growth of orthotopically implanted tumors. Mechanically, GRIK3 influenced a range of signaling pathways and key signal transducers, including two epithelial-mesenchymal transition regulators, SPDEF and CDH1. Heterogenous expression of SPDEF and CDH1 counteracted the migration and invasion abilities, respectively, of breast cancer cells induced by GRIK3. Moreover, overexpression of GRIK3 increased the expression of mesenchymal markers and decreased the expression of epithelial markers, resulting in the translocation of ß-catenin into the nucleus and the increased ß-catenin transcriptional activity. In conclusion, the present study reported a novel oncogenic role of GRIK3. Meanwhile, GRIK3, as a membrane receptor, may also serve as a potential therapeutic target for the treatment of breast cancer.

Glutamate metabotropic receptor 4 (GRM4) inhibits cell proliferation, migration and invasion in breast cancer and is regulated by miR-328-3p and miR-370-3p.

BACKGROUND: Glutamate metabotropic receptors (GRM) play a variety of roles in neuronal cells. However, their clinical significance and biological functions in breast cancer remain unknown. METHODS: RNA sequencing data of breast cancer was obtained from the TCGA dataset (v2) and mined for the expression profiles of GRM family according to cancer subtypes. mRNA expression of GRM family in breast cancer tissues and para-cancerous tissue samples as well as breast cancer cell lines were measured by qPCR. The effects of over- and under-expression of GRM4 on cell capabilities to survive, migrate and invade were determined by colony formation, transwell migration and invasion assays. To explore the upstream regulation pattern of GRM4, miRNAs that target GRM4 were predicted and validated by dual luciferase reporter assay. In addition, the mRNA and protein expression of GRM4 regulated by these miRNAs were further measured by qPCR and western blot assay. RESULTS: GRM4 was the only GRM member that expressed in breast cancer tissues. Ectopic expression of GRM4 was correlated with better prognosis of breast cancer patients. Overexpression of GRM4 could significantly inhibit cell proliferation, migration and invasion capacity in MDA-MB-231, while knockdown of GRM4 could promote these processes. miR-328-3p and miR-370-3p were predicted to regulate the expression of GRM4 and dual luciferase reporter assay demonstrated that miR-328-3p and miR-370-3p directly bound to the 3' UTR of GRM4 and mutations on the binding regions on GRM4 significantly decreased the luciferase activity. qPCR demonstrated that expression of miR-328-3p and miR-370-3p was significantly decreased in breast cancer tissues and cells compared with that in control samples. However, there were no correlations between the expression of miR-328-3p and GRM4, as well as the expression of miR-370-3p and GRM4. Moreover, overexpression of miR-328-3p and miR-370-3p counteracted the inhibitory effect of GRM4-induced cell proliferation, migration and invasion. CONCLUSIONS: Our results suggest that GRM4 might be a tumor suppressor gene in breast cancer under the direct regulation of miR-328-3p and miR-370-3p.

Identification of key genes relevant to the prognosis of ER-positive and ER-negative breast cancer based on a prognostic prediction system.

Few prognostic indicators with differential expression have been reported among the differing ER statuses. We aimed to screen important breast cancer prognostic genes related to ER status and to construct an efficient prognostic prediction system. mRNA expression profiles were downloaded from TCGA and GSE70947 dataset. Two hundred seventy-one overlapping differentially expressed genes (DEGs) between the ER- and ER+ breast cancer samples were identified. Among the 271 DEGs, 109 prognostically relevant mRNAs were screened. mRNAs such as RASEF, ITM2C, CPEB2, ESR1, ANXA9, and VASN correlated strongly with breast cancer prognosis. Three modules, which contained 28, 9 and 8 enriched DEGs, were obtained from the network, and the DEGs in these modules were enriched in response to hormone stimulus, epithelial cell development, and host cell entry. Using bayes discriminant analysis, 48 signature genes were screened. We constructed a prognostic prediction system using the 48 signature genes and validated this system as relatively accurate and reliable. The DEGs might be closely associated with the prognosis in patients with breast cancer. We validated the effectiveness of our prognostic prediction system by GEO database. Therefore, this system might be a useful tool for preliminary screening and validation of potential prognosis indicators for ER+ breast cancer derived from mechanistic research.

Identification of methylation sites and signature genes with prognostic value for luminal breast cancer.

BACKGROUND: Robust and precise molecular prognostic predictors for luminal breast cancer are required. This study aimed to identify key methylation sites in luminal breast cancer, as well as precise molecular tools for predicting prognosis. METHODS: We compared methylation levels of normal and luminal breast cancer samples from The Cancer Genome Atlas dataset. The relationships among differentially methylated sites, corresponding mRNA expression levels and prognosis were further analysed. Differentially expressed genes in normal and cancerous samples were analysed, followed by the identification of prognostic signature genes. Samples were divided into low- and high-risk groups based on the signature genes. Prognoses of low- and high-risk groups were compared. The Gene Expression Omnibus dataset were used to validate signature genes for prognosis prediction. Prognosis of low- and high-risk groups in Luminal A and Luminal B samples from the TCGA and the Metabric cohort dataset were analyzed. We also analysed the correlation between clinical features of low- and high- risk groups as well as their differences in gene expression. RESULTS: Fourteen methylation sites were considered to be related to luminal breast cancer prognosis because their methylation levels, mRNA expression and prognoses were closely related to each other. The methylation level of SOSTDC1 was used to divide samples into hypo- and hyper-methylation groups. We also identified an mRNA signature, comprising eight transcripts, ESCO2, PACSIN1, CDCA2, PIGR, PTN, RGMA, KLK4 and CENPA, which was used to divide samples into low- and high-risk groups. The low-risk group showed significantly better prognosis than the high-risk group. A correlation analysis revealed that the risk score was an independent prognostic factor. Low- and high- risk groups significantly correlated with the survival ratio in Luminal A samples, but not in Luminal B samples on the basis of the TCGA and the Metabric cohort dataset. Further functional annotation demonstrated that the differentially expressed genes were mainly involved in cell cycle and cancer progression. CONCLUSIONS: We identified several key methylation sites and an mRNA signature for predicting luminal breast cancer prognosis. The signature exhibited effective and precise prediction of prognosis and may serve as a prognostic and diagnostic marker for luminal breast cancer.

Synchronized Progression of Prestin Expression and Auditory Brainstem Response during Postnatal Development in Rats.

Prestin is the motor protein expressed in the cochlear outer hair cells (OHCs) of mammalian inner ear. The electromotility of OHCs driven by prestin is responsible for the cochlear amplification which is required for normal hearing in adult animals. Postnatal expression of prestin and activity of OHCs may contribute to the maturation of hearing in rodents. However, the temporal and spatial expression of prestin in cochlea during the development is not well characterized. In the present study, we examined the expression and function of prestin from the OHCs in apical, middle, and basal turns of the cochleae of postnatal rats. Prestin first appeared at postnatal day 6 (P6) for basal turn, P7 in middle turn, and P9 for apical turn of cochlea. The expression level increased progressively over the next few days and by P14 reached the mature level for all three segments. By comparison with the time course of the development of auditory brainstem response for different frequencies, our data reveal that prestin expression synchronized with the hearing development. The present study suggests that the onset time of hearing may require the expression of prestin and is determined by the mature function of OHCs.

Evaluation of the analytical and clinical performances of time-resolved fluoroimmunoassay for detecting carcinoma antigen 50.

We developed a TR-FIA kit for quantitative detection of CA50. This study aims to evaluate the analytical and clinical performances of this kit. Precision, accuracy, specificity, sensitivity, stability, and endogenous interference of this kit are evaluated. Reference range is established. Coincidence rate and correlation between TR-FIA and RIA are evaluated. ROC is adopted to evaluate the diagnostic performance. This kit shows excellent precision with a coefficients of variation (CVs) ranged from 2.2-9.3%, accuracy (average recovery, 98.5%), sensitivity (minimum detectable concentration is 0.2 U/mL), specificity (all cross-reactivity is less than 0.1% except CA199, which is 0.175%), and storage stability (recoveries, 90.8-100.4%). Bilirubin, hemoglobin, and triglyceride dose not interfere with CA50 detection (recovery, 97.13-109.1%). The range from 0-25 U/mL is chosen as the reference range. There are good correlation (r = 0.804) and coincidence (p = 0.608, kappa = 0.924) between TR-FIA and RIA. Diagnostic performance of this kits, which based on RIA results, is perfect (AUC = 0.996), and the diagnostic accuracy for malignancy diagnosis is in moderate degree (AUC, 0.802-0.861). The TR-FIA (CA50) kit performs well in analytical and clinical performances, and can be employed in the clinical diagnosis of malignancy.

[Prevention and control of SARS-CoV-2 infection in clinical laboratories: implementation of contingency plan and postpandemic response strategies].

The outbreak of COVID-19 has currently been under control in China, but now the disease has rapidly evolved into a global pandemic. We formulated a prevention and control plan for clinical laboratories responsible for detection of the novel coronavirus infection. We analyzed the implementation of this plan and the problems arising from its clinical practice. We found that the layout of most clinical laboratories (including gene amplification laboratories for clinical samples) was inadequate in response to a major outbreak and did not meet the requirements for biosafety protection and etiology and serology testing; and laboratory staff showed insufficiencies in their awareness regarding biosafety protection; the functions and status of the laboratory in the fever clinic need to be enhanced to increase its detection capacity; the high density of military personnel, the low level of automation of clinical laboratory equipment, and the lack of biosafety cabinets and personal protective equipment all limit the performance of diverse military operations and major overseas missions. In view of these problems, we propose the following strategies and recommendations: the clinical laboratory needs to standardize the design and staff management according to the standards of P2 laboratory; the detection capacity and staffing of fever clinic laboratory in hospitals need to be strengthened, and a separate clinical gene amplification laboratory can be optimal; for those clinical gene amplification laboratories that fail to meet these standards, reconstruction and upgrade should be made according to the requirements of biosafety protection; for the clinical laboratory in the military medical system, in addition to enforcement of biological safety protection of the staff, sufficient supply of medical materials and biological safety equipment should be ensured and biological safety cabinets should be routinely equipped if possible.

Asymmetric synthesis of beta,gamma-unsaturated alpha-amino acids via efficient kinetic resolution with cinchona alkaloids.

The beta,gamma-unsaturated amino acids are versatile chiral building blocks and biologically interesting compounds. The asymmetric synthesis of beta,gamma-unsaturated amino acids presents a challenging task as these compounds are labile toward racemization as well as the undesirable double bond isomerization. An efficient, general and mild kinetic resolution with readily accessible and fully recyclable cinchona alkaloid catalysts has been developed to provide a reliably useful approach toward optically active beta,gamma-unsaturated amino acids.

[Structure and function of B-cell linker and its role in the development of B cell-related diseases].

B cell linker (BLNK) is a key linker protein of B cell receptor (BCR) signaling pathway. BLNK participates in the regulation of PLC-γactivity and the activation of Ras pathway through its typical structure and interaction network with other proteins, and is thus widely involved in the regulation of B cell proliferation, differentiation, apoptosis and signal transduction. Furthermore, it is closely related to anaphylactic diseases, multiple sclerosis, chromosomal aneuploidy, aneuglobulinemia, B lymphocytic leukemia and lymphoma. Herein we review the structure and biological function of BLNK and its role in B cell-related diseases. BLNK can cooperate with a series of effective proteins to activate BCR signaling pathway, thereby regulating the development, maturation and function of B cells. The functional mutation of BLNK can destroy the homeostasis of B cells and affect the development and maturation of B cells, which leads to the occurrence of B cell related diseases. A comprehensive understanding of the biological functions of BLNK not only provides insights into the pathogenesis of B cell-related diseases, but also inspires new ideas and helps to find breakthroughs for the treatment of these diseases with BLNK as the therapeutic target.

Analysis of the miRNA-mRNA-lncRNA network in human estrogen receptor-positive and estrogen receptor-negative breast cancer based on TCGA data.

Estrogen receptor-positive (ER+) and ER-negative (ER-) subtypes of breast cancer have distinct clinical outcomes because they respond differentially to endocrine therapies. We aimed to comprehensively analyze differentially expressed microRNA (miRNAs), long non-coding RNAs (lncRNAs) and mRNAs in different ER subtypes as well as to identify prognosis-related RNAs. The expression levels of miRNAs, lncRNAs, and mRNAs between breast cancer and normal samples were compared using data from The Cancer Genome Atlas database. Differentially expressed miRNAs, lncRNAs and mRNAs between ER+ and ER- samples were also screened. An ER subtype-related miRNA-lncRNA-mRNA network was constructed. lncRNAs and mRNAs in this network were further subjected to an analysis of their associations with patient prognosis. Sets of differentially expressed miRNAs, lncRNAs, and miRNAs between breast cancer and normal samples were identified among which 14 miRNAs, 78 lncRNAs, and 475 mRNAs were differentially expressed between ER subtypes. Relationships between these RNAs were analyzed. The resultant ER subtype-related miRNA-lncRNA-mRNA network consisted of 14 nodes, among which LINC0092 and chromosome 2 open reading frame 71 (C2orf71) were correlated with better prognosis of breast cancer. LINC0092 was co-expressed with SFRP1 and RGMA and regulated by hsa-miR-449a and hsa-miR-452-5p. C2orf71 was co-expressed with LINC00511 and regulated by hsa-miR-184. Cross-talk among differentially expressed miRNAs, lncRNAs, and miRNAs may be an important feature in ER+ and ER- subtypes of breast cancer. LINC0092 and C2orf71, two of these cross-talking RNAs, may serve as novel prognostic predictor of breast cancer because of their close associations with prognosis.

[Preparation and evaluation of a time-resolved fluoroimmunoassay kit for CA50 determination].

OBJECTIVE: To prepare a rapid and sensitive diagnostic kit for detection of CA50 based on time-resolved fluoroimmunoassay. METHODS: A sandwich-TRFIA diagmostic kit was developed using anti-CA50 monoclonal antibody and all parameters of the kit were evaluated. RESULTS: The linear measurement range of the kit was (5 - 300) U/ml. The sensitivity was 0.2 U/ml. The intra- and inter-assay coefficients of variation were 4.3% - 8.2% and 7.7% - 11.2%, respectively. There was no cross-reaction with CEA, CA12-5, CA15-3 and AFP. The cross reactivity with CA19-9 was 0.7 U/ml. The correlation coefficient of detection results of 107 blood samples between this newly developed kit and commercially available CA50 RIA kit was 0.901. CONCLUSION: This newly developed CA50-TRFIA kit is a valuable test tool for clinical application with even better sensitivity, specificity and accuracy.

A flexible Sb2O3/carbon cloth composite as a free-standing high performance anode for sodium ion batteries.

A flexible Sb2O3/carbon cloth (CC) composite is synthesized using a simple solvothermal method. The Sb2O3/CC composite exhibits higher capacity and capacity retention of alloying and conversion reactions as an anode for sodium ion batteries, attributed to the good conductivity of CC and strong chemical bonds between Sb2O3 and CC.

[Preparation of time-resolved fluoroimmunoassay kit for human alpha-fetoprotein detection].

OBJECTIVE: To prepare time-resolved fluoroimmunoassay (TRFIA) kit for detecting human alpha-fetoprotein (hAFP). METHODS: Sandwich TRFIA kit for hAFP detection was developed using monoclonal antibody of anti-AFP. RESULTS: AFP-TRFIA kit was capable of detecting AFP within the range of 1-1 000 U/ml with sensitivity of 0.17 U/ml and without cross-reactivity with CEA, CA12-5, CA15-3, or CA19-9. The intra- and inter-assay coefficients of variation were (3.3-5.9)% and (3.7-6.5)%, respectively. The prepared AFP-TRFIA reagent could withstand preservation at 4 degrees celsius; for 1 year and at 37 degrees celsius; for 7 days with the cutoff value of 12 U/ml in healthy subjects (n=426). The correlation coefficient of the detection results between this kit and commercially available AFP kit (Wallac OY, Finland) for 60 blood samples was 0.995. CONCLUSION: The prepared TRFIA kit for hAFP detection meets the demand of clinical application with good sensitivity, precision, specificity, stability and accuracy.

Development of a rapid, room-temperature dynamic kinetic resolution for efficient asymmetric synthesis of alpha-aryl amino acids.

[reaction: see text] A rapid, highly efficient and general dynamic kinetic resolution (DKR) of racemic alpha-aryl UNCAs with the dual-function catalysis of modified cinchona alkaloid was accomplished at room temperature. This DKR led to the development of a highly enantioselective catalytic method for the practical synthesis of a wide range of alpha-aryl and alpha-heteroaryl amino acids in 89-92% ee and 86-95% yield from racemic UNCAs.

Preclinical evaluation of the synthetic adjuvant SQS-21 and its constituent isomeric saponins.

The saponin fraction QS-21 from Quillaja saponaria has been demonstrated to be a potent immunological adjuvant when mixed with keyhole limpet hemocyanin conjugate vaccines, as well as with other classes of subunit antigen vaccines. QS-21 adjuvant is composed of two isomers that include the apiose and xylose forms in a ratio of 65:35, respectively. The chemical syntheses of these two isomers in pure form have recently been disclosed. Herein we describe detailed in vivo immunological evaluations of these synthetic QS-21 isomeric constituents, employing the GD3-KLH melanoma antigen. With this vaccine construct, high antibody titers against GD3 ganglioside and KLH were elicited when GD3-KLH was co-administered with adjuvant, either as the individual separate synthetic QS-21 isomers (SQS-21-Api or SQS-21-Xyl), or as its reconstituted 65:35 isomeric mixture (SQS-21). These antibody titer levels were comparable to that elicited by vaccinations employing naturally derived QS-21 (PQS-21). Moreover, toxicities of the synthetic saponin adjuvants were also found to be comparable to that of naturally derived PQS-21. These findings demonstrate unequivocally that the adjuvant activity of QS-21 resides in these two principal isomeric forms, and not in trace contaminants within the natural extracts. This lays the foundation for future exploration of structure-function correlations to enable the discovery of novel saponins with increased potency, enhanced stability, and attenuated toxicity.

[Time-resolved fluoroimmunoassay of carcino-embryonic antigen and preparation of its diagnostic reagent].

AIM: To establish a two-site time-resolved fluoroimmunoassay (TRFIA) for detection of carcino-embryonic antigen(CEA) based on the direct sandwich technique(One monoclonal antibody(mAb) is immobilized on the surface of microtiter plate strip wells, another mAb is labelled with Eu(3+)) and prepare its diagnostic reagent. METHODS: The sandwich TRFIA for detection of serum CEA level using anti-CEA mAbs was used. RESULTS: The measure range of CEA-TRFIA was (1-560) microg/L. The analytical sensitivity was 0.28 mug/L. The intra- and inter-assay coefficients of variation (CV) were 7.2%-8.6% and 8.9%-13.2%, respectively. There was no cross-reaction to AFP, CA12-5, CA19-9 and albumin. Cross reactivity to CA15-3 was 1.62 microg/L. The correlation coefficient of blood samples detected by CEA-TRFIA and commercially available CEA CLIA (chemiluminescent immunoassay) kit (Roche) was 0.946. CONCLUSION: CEA-TRFIA is a new immunoassay which has several advantages including high sensitivity, specificity and a wide working range. It is suitable for routine clinical use.

Asymmetric organic catalysis with modified cinchona alkaloids.

Insights into the role played by modified cinchona alkaloids in the Sharpless asymmetric dihydroxylation inspired studies of modified cinchona alkaloids as chiral organic catalysts that lead to the development of highly enantioselective alcoholyses for the desymmetrization, kinetic resolution, and dynamic kinetic resolution of cyclic anhydrides, cyanation of ketones, and 1,4-addition of thiols to cylic enones. These studies demonstrate the potential of modified cinchona alkaloids as broadly useful chiral organic catalysts for asymmetric synthesis.