Ultrasensitive Detection of Organophosphorus Pesticides Using Single-Molecule Conductance Measurement.

Detection of organophosphorus pesticides (OPs) with high sensitivity in environmental samples is of vital importance for environmental safety and human health. However, it remains a challenge to achieve fM (10-15 mol/L) sensitivity for detecting OPs. Herein, we developed an acetylcholinesterase sensor based on 3,3',5,5'-tetramethylbenzidine (TMB) combining an enzyme-mediated strategy and scanning tunneling microscopy break junction (STM-BJ). Benefiting from the enzyme inhibition kinetics of OPs and the customized spectral clustering analysis method, our new strategy achieved the detection of methamidophos (MTMP) with a limit of 10 aM (10-17 mol/L) and 3 times higher selectivity in mixed OPs. As applied to natural lake waters, it also exhibited high reproducibility, high stability, and good recovery. This work paves a new avenue toward the application of single-molecule conductance characterizations for biochemical analysis and environmental monitoring.

CRISPR-cas technology: A key approach for SARS-CoV-2 detection.

The CRISPR (Clustered Regularly Spaced Short Palindromic Repeats) system was first discovered in prokaryotes as a unique immune mechanism to clear foreign nucleic acids. It has been rapidly and extensively used in basic and applied research owing to its strong ability of gene editing, regulation and detection in eukaryotes. Hererin in this article, we reviewed the biology, mechanisms and relevance of CRISPR-Cas technology and its applications in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnosis. CRISPR-Cas nucleic acid detection tools include CRISPR-Cas9, CRISPR-Cas12, CRISPR-Cas13, CRISPR-Cas14, CRISPR nucleic acid amplification detection technology, and CRISPR colorimetric readout detection system. The above CRISPR technologies have been applied to the nucleic acid detection, including SARS-CoV-2 detection. Common nucleic acid detection based on CRISPR derivation technology include SHERLOCK, DETECTR, and STOPCovid. CRISPR-Cas biosensing technology has been widely applied to point-of-care testing (POCT) by targeting recognition of both DNA molecules and RNA Molecules.

Leaf water potential of field crops estimated using NDVI in ground-based remote sensing-opportunities to increase prediction precision.

Remote-sensing using normalized difference vegetation index (NDVI) has the potential of rapidly detecting the effect of water stress on field crops. However, this detection has typically been accomplished only after the stress effect led to significant changes in crop green biomass, leaf area index, angle and position, and few studies have attempted to estimate the uncertainties of the regression models. These have limited the informed interpretation of NDVI data in agricultural applications. We built a ground-based sensing cart and used it to calibrate the relationships between NDVI and leaf water potential (LWP) for wheat, corn, and cotton growing under field conditions. Both the methods of ordinary least-squares (OLS) and weighted least-squares (WLS) were employed in data analysis, and measurement errors in both LWP and NDVI were considered. We also used statistical resampling to test the effect of measurement errors of LWP on the uncertainties of model coefficients. Our data showed that obtaining a high value of the coefficient of determination did not guarantee a high prediction precision in the obtained regression models. Large prediction uncertainties were estimated for all three crops, and the regressions obtained were not always significant. The best models were obtained for cotton with a prediction uncertainty of 27%. We found that considering measurement errors for both LWP and NDVI led to reduced uncertainties in model coefficients. Also, reducing the sample size of LWP measurement led to significantly increased uncertainties in the coefficients of the linear models describing the LWP-NDVI relationship. Finally, potential strategies for reducing the uncertainty relative to the range of NDVI measurement are discussed.

Immune signature-based hepatocellular carcinoma subtypes may provide novel insights into therapy and prognosis predictions.

BACKGROUND: Hepatocellular carcinoma (HCC) has a poor prognosis and has become the sixth most common malignancy worldwide due to its high incidence. Advanced approaches to therapy, including immunotherapeutic strategies, have played crucial roles in decreasing recurrence rates and improving clinical outcomes. The HCC microenvironment is important for both tumour carcinogenesis and immunogenicity, but a classification system based on immune signatures has not yet been comprehensively described. METHODS: HCC datasets from The Cancer Genome Atlas (TCGA), the Gene Expression Omnibus (GEO), and the International Cancer Genome Consortium (ICGC) were used in this study. Gene set enrichment analysis (GSEA) and the ConsensusClusterPlus algorithm were used for clustering assessments. We scored immune cell infiltration and used linear discriminant analysis (LDA) to improve HCC classification accuracy. Pearson's correlation analyses were performed to assess relationships between immune signature indices and immunotherapies. In addition, weighted gene co-expression network analysis (WGCNA) was applied to identify candidate modules closely associated with immune signature indices. RESULTS: Based on 152 immune signatures from HCC samples, we identified four distinct immune subtypes (IS1, IS2, IS3, and IS4). Subtypes IS1 and IS4 had more favourable prognoses than subtypes IS2 and IS3. These four subtypes also had different immune system characteristics. The IS1 subtype had the highest scores for IFNγ, cytolysis, angiogenesis, and immune cell infiltration among all subtypes. We also identified 11 potential genes, namely, TSPAN15, TSPO, METTL9, CD276, TP53I11, SPINT1, TSPO, TRABD2B, WARS2, C9ORF116, and LBH, that may represent potential immunological biomarkers for HCC. Furthermore, real-time PCR revealed that SPINT1, CD276, TSPO, TSPAN15, METTL9, and WARS2 expression was increased in HCC cells. CONCLUSIONS: The present gene-based immune signature classification and indexing may provide novel perspectives for both HCC immunotherapy management and prognosis prediction.

Reduced Energy Metabolism Impairs T Cell-Dependent B Cell Responses in Patients With Advanced HBV-Related Cirrhosis.

Background and Aims: Patients with decompensated HBV-related liver cirrhosis (HBV D-LC) showed compromised immune responses, which manifested as a proneness to develop infections and hyporesponsiveness to vaccines, resulting in accelerated disease progression. The alterations in T cell-dependent B cell responses in this pathophysiological process were not well understood. This study aimed to investigate T cell-dependent B cell responses in this process and discuss the mechanism from the perspective of metabolism. Methods: Changes in phenotypes and subsets of peripheral B cells between HBV D-LC patients and healthy controls (HCs) were compared by flow cytometry. Isolated B cells were activated by coculture with circulating T follicular (cTfh) cells. After coculture, the frequencies of plasmablasts and plasma cells and immunoglobin levels were analyzed. Oxidative phosphorylation (OXPHOS) and glycolysis were analyzed by a Seahorse analyzer. Mitochondrial function and the AKT/mTOR pathway were analyzed by flow cytometry. Results: The proliferation and differentiation capacities of B cells after T cell stimulation were impaired in D-LC. Furthermore, we found that B cells from D-LC patients showed reductions in OXPHOS and glycolysis after activation, which may result from reduced glucose uptake, mitochondrial dysfunction and attenuated activation of the AKT/mTOR pathway. Conclusions: B cells from HBV D-LC patients showed dysfunctional energy metabolism after T cell-dependent activation. Understanding the regulations of B cell metabolic pathway and their changes may provide a new direction to rescue B cell hyporesponsiveness in patients with HBV D-LC, preventing these patients be infected and improving sensitivity to vaccines.

Detection and Significance of PNC in Breast Cancer Tissues.

BACKGROUND: The PNC (perinucleolar compartment) associates with malignancy of various solid tumors. Our study was to detect the expression level of PNC in breast cancer tissues and analyze the clinical significance. METHODS: Immunohistochemistry and immunofluorescence were used to detect the expression of PNC in breast cancer tissues, para-cancer tissues, and lymph nodes. RESULTS: We used immunohistochemistry to detect PNC in paraffin tissues of breast cancer. PNC was expressed in 66.67% breast cancer tissues and 60.87% lymph node tissues, but not corresponding para-cancer tissues. PNC was not correlated with ER, PR, tumor size, and lymph node infiltration (all p > 0.05), but was correlated with TNM (p < 0.05). Immunofluorescence was used to detect PNC, 64.29% breast cancer tissues and 75% lymph node tissues were positive, but all adjacent tissues were negative. PNC was detected by immunohistochemistry and immunofluorescence in 14 breast cancer tissues and para-cancer tissues simultaneously. Nine cases were positive by immunofluorescence and 6 cases were positive by immunohistochemistry, with a coincidence rate of 66.67%. PNC of para-cancer tissues were detected negative by both methods, and the coincidence rate was 100%. CONCLUSIONS: The expression of PNC in breast cancer tissues was higher than that in para-cancer tissues. There was no significant correlation between PNC and breast cancer invasion and metastasis.

Eleven routine clinical features predict COVID-19 severity uncovered by machine learning of longitudinal measurements.

Severity prediction of COVID-19 remains one of the major clinical challenges for the ongoing pandemic. Here, we have recruited a 144 COVID-19 patient cohort, resulting in a data matrix containing 3,065 readings for 124 types of measurements over 52 days. A machine learning model was established to predict the disease progression based on the cohort consisting of training, validation, and internal test sets. A panel of eleven routine clinical factors constructed a classifier for COVID-19 severity prediction, achieving accuracy of over 98% in the discovery set. Validation of the model in an independent cohort containing 25 patients achieved accuracy of 80%. The overall sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 0.70, 0.99, 0.93, and 0.93, respectively. Our model captured predictive dynamics of lactate dehydrogenase (LDH) and creatine kinase (CK) while their levels were in the normal range. This model is accessible at https://www.guomics.com/covidAI/ for research purpose.

NUF2 as an anticancer therapeutic target and prognostic factor in breast cancer.

Breast cancer (BC) is the most frequently diagnosed type of cancer, and the leading cause of cancer­associated mortality in females worldwide. The aim of the present study was to investigate the prognostic and therapeutic potential of NUF2 in BC. The expression levels of NUF2 in BC tissues and cell lines were evaluated via bioinformatics, reverse transcription­quantitative PCR, western blot analysis and immunohistochemistry (IHC). In addition, the effect of NUF2 knockdown on BC cell proliferation and apoptosis was investigated using small interfering RNA (siRNA) technology. Bioinformatics and IHC analysis showed that NUF2 was overexpressed in BC tissues. Furthermore, western blot and RT­qPCR analyses demonstrated that NUF2 was upregulated in BC cells. In addition, BC cells transfected with NUF2 siRNA exhibited significantly decreased proliferation and colony formation, and increased apoptosis, compared with the control. Additionally, cell cycle analysis revealed that NUF2 induced G0/G1 cell cycle arrest by inhibiting cyclin B1 expression. Collectively, the present study suggested that NUF2 may represent a promising prognostic biomarker and a potential therapeutic target for BC.

Serum Exosomal miR-17-5p as a Promising Biomarker Diagnostic Biomarker for Breast Cancer.

BACKGROUND: The biological role of exosomes has attracted widespread attention in various fields of biomedicine. Exosome-delivered microRNAs (miRNAs) play crucial roles in cancer diagnosis. The aim of our study was to examine whether serum exosomal miR-17-5p could be identified as a diagnostic biomarker for breast cancer (BC). METHODS: Eighty-three patients diagnosed with BC and thirty-four healthy women (controls) were included in this study. The expression level of serum exosomal miR-17-5p was identified by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and calculated by 2-ΔΔCq method. RESULTS: Reduced level of exosomal miR-17-5p in serum from BC patients was found compared with healthy controls. In addition, miR-17-5p also had low expression in 34 pairs of tissue and serum samples. MiR-17-5p was highly concentrated in serum exosomes and the expression level was stable. In addition, the exosomal miR-17-5p could distinguish BC from healthy controls with the area under the ROC curve (AUC) of 0.784 (p < 0.0001, sensi¬tivity = 66.67%, specificity = 83.95%). The sensitivity and specificity of miR-17-5p were superior to conventional se¬rum biomarkers CEA, CA125, and CA153. We predicted target genes of miR-17-5p were also mainly involved in cancer-related pathways. CONCLUSIONS: In conclusion, our findings strongly suggested that serum exosomal miR-17-5p could serve as a novel diagnostic biomarker for BC.

Screening of differentially expressed genes and identification of NUF2 as a prognostic marker in breast cancer.

The aims of the present study were to screen differentially expressed genes (DEGs) in breast cancer (BC) and investigate NDC80 kinetochore complex component (NUF2) as a prognostic marker of BC in detail. A total of four BC microarray datasets, downloaded from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases, were used to screen DEGs. A total of 190 DEGs with the same expression trends were identified in the 4 datasets, including 65 upregulated and 125 downregulated DEGs. Functional and pathway enrichment analyses were performed using the Database for Annotation, Visualization and Integrated Discovery. The upregulated DEGs were enriched for 10 Gene Ontology (GO) terms and 7 pathways, and the downregulated DEGs were enriched for 10 GO terms and 10 pathways. A protein­protein interaction network containing 149 nodes and 930 edges was constructed using the Search Tool for the Retrieval of Interacting Genes, and 2 functional modules were identified using the MCODE plugin of Cytoscape. Based on an in­depth analysis of module 1 and literature mining, NUF2 was selected for further research. Oncomine database analysis and reverse transcription­quantitative PCR showed that NUF2 is significantly upregulated in BC tissues. In analyses of correlations between NUF2 and clinical pathological characteristics, NUF2 was significantly associated with the malignant features of BC. Using 5 additional datasets from GEO, it was demonstrated that NUF2 has a significant prognostic role in both ER­positive and ER­negative BC. A Gene Set Enrichment Analysis indicated that NUF2 may regulate breast carcinogenesis and progression via cell cycle­related pathways. The results of the present study demonstrated that NUF2 is overexpressed in BC and is significantly associated with its multiple pathological features and prognosis.

miR-17-5p promotes migration and invasion in breast cancer cells by repressing netrin 4.

Netrin 4 (NTN4) is downregulated in breast cancer (BC) and can inhibit the migration of BC cells. miRNAs dysregulation plays prominent roles in BC tumorigenesis. However, the function of miR-17-5p, its relationship with NTN4 and its underlying functional mechanism in BC are unclear and were investigated in the current study. Compared with normal breast samples, miR-17-5p was upregulated in BC specimens in The Cancer Genome Atlas (TCGA). A clinical analysis based on TCGA showed that miR-17-5p expression correlated with BC tumor stage, lymph node status, estrogen receptor, and progesterone receptor status. A wound-healing assay and Transwell assay implied that miR-17-5p upregulation promotes BC cell migration and invasion. Reverse transcription-quantitative PCR and ELISA showed that NTN4 mRNA and protein were both downregulated after miR-17-5p was overexpressed in Hs578T cells, whereas miR-17-5p inhibition had the opposite effect in MCF-7 cells. We also performed a dual-fluorescent reporter assay, the results of which demonstrated that miR-17-5p represses NTN4 expression by directly targeting the 3' untranslated region of NTN4 mRNA. In summary, miR-17-5p considerably promotes BC cell migration by suppressing NTN4 expression, and may therefore offer a potential therapeutic target for BC.

Diagnostic value of α-enolase expression and serum α-enolase autoantibody levels in lung cancer.

OBJECTIVE: To investigate the diagnostic value of α-enolase (ENO1) and serum ENO1 autoantibody levels in lung cancer. METHODS: Immunohistochemistry staining and ELISA were performed to detect ENO1 expression in lung tissue and serum ENO1 autoantibody levels, respectively. RESULTS: The expression of ENO1 was higher in lung cancer tissues than in benign lung disease tissues (p < 0.001). The proportion of lung cancer samples expressing ENO1 was not significantly different among the various pathological classification groups. The proportion of samples expressing ENO1 was higher in lung cancer patients in stages I/II than in those in stages III/IV (χ2 = 5.445; p = 0.018). The expression of ENO1 in lung cancer tissues was not associated with age, gender, or smoking history. Serum ENO1 antibody levels were significantly higher in the lung cancer group than in the benign lung disease and control groups (p < 0.001). The differences among the pathological classification groups were not statistically significant. Serum ENO1 antibody levels were also in lung cancer patients in stages I/II than in those in stages III/IV (p < 0.01). Serum ENO1 antibody levels were not associated with age, gender, or smoking history in lung cancer patients. The ROC curve representing the diagnosis of lung cancer based on ENO1 antibody levels had an area under the curve of 0.806. CONCLUSIONS: Our results suggest that high levels of ENO1 are associated with the clinical stage of lung cancer and that ENO1 expression and its serum autoantibody levels show diagnostic value in lung cancer.

Diagnostic value of α-enolase expression and serum α-enolase autoantibody levels in lung cancer / Valor diagnóstico da expressão de α-enolase e dos níveis séricos de autoanticorpos contra α-enolase no câncer de pulmão

ABSTRACT Objective: To investigate the diagnostic value of α-enolase (ENO1) and serum ENO1 autoantibody levels in lung cancer. Methods: Immunohistochemistry staining and ELISA were performed to detect ENO1 expression in lung tissue and serum ENO1 autoantibody levels, respectively. Results: The expression of ENO1 was higher in lung cancer tissues than in benign lung disease tissues (p < 0.001). The proportion of lung cancer samples expressing ENO1 was not significantly different among the various pathological classification groups. The proportion of samples expressing ENO1 was higher in lung cancer patients in stages I/II than in those in stages III/IV (χ2 = 5.445; p = 0.018). The expression of ENO1 in lung cancer tissues was not associated with age, gender, or smoking history. Serum ENO1 antibody levels were significantly higher in the lung cancer group than in the benign lung disease and control groups (p < 0.001). The differences among the pathological classification groups were not statistically significant. Serum ENO1 antibody levels were also in lung cancer patients in stages I/II than in those in stages III/IV (p < 0.01). Serum ENO1 antibody levels were not associated with age, gender, or smoking history in lung cancer patients. The ROC curve representing the diagnosis of lung cancer based on ENO1 antibody levels had an area under the curve of 0.806. Conclusions: Our results suggest that high levels of ENO1 are associated with the clinical stage of lung cancer and that ENO1 expression and its serum autoantibody levels show diagnostic value in lung cancer.

RESUMO Objetivo: Investigar o valor diagnóstico da α-enolase (ENO1) e dos níveis séricos de autoanticorpos contra ENO1 no câncer de pulmão. Métodos: Marcação imuno-histoquímica e ELISA foram realizados para detectar a expressão de ENO1 no tecido pulmonar e os níveis séricos de autoanticorpos contra ENO1, respectivamente. Resultados: A expressão de ENO1 foi maior nos tecidos de câncer de pulmão que nos tecidos de doença pulmonar benigna (p < 0,001). Não houve diferença significativa entre os diversos grupos de classificação patológica quanto à proporção de amostras de câncer de pulmão que expressaram ENO1. A proporção de amostras que expressaram ENO1 foi maior nos pacientes com câncer de pulmão nos estágios I/II que naqueles com câncer de pulmão nos estágios III/IV (χ2 = 5,445; p = 0,018). Não houve relação entre a expressão de ENO1 em tecidos de câncer de pulmão e idade, sexo ou histórico de tabagismo. Os níveis séricos de anticorpos contra ENO1 foram significativamente maiores no grupo câncer de pulmão que nos grupos doença pulmonar benigna e controle (p < 0,001). As diferenças entre os grupos de classificação patológica não foram estatisticamente significativas. Os níveis séricos de anticorpos contra ENO1 foram também significativamente maiores nos pacientes com câncer de pulmão nos estágios I/II que naqueles com câncer de pulmão nos estágios III/IV (p < 0,01). Nos pacientes com câncer de pulmão, não houve relação entre os níveis séricos de anticorpos contra ENO1 e idade, sexo ou histórico de tabagismo. A curva ROC do diagnóstico de câncer de pulmão baseado nos níveis de anticorpos contra ENO1 apresentou área sob a curva = 0,806. Conclusões: Nossos resultados sugerem que há relação entre níveis elevados de ENO1 e o estágio clínico do câncer de pulmão e que a expressão de ENO1 e os níveis séricos de autoanticorpos contra ENO1 têm valor diagnóstico no câncer de pulmão.

Enterovirus 71 infection impairs the reproductive capacity of female mice.

Enterovirus 71 (EV71) is a major cause of hand, foot and mouth disease (HFMD); however, no clinically approved vaccine or antiviral treatment is currently available for EV71 infection. In the present study, a murine model of EV71 infection was constructed. The clinical isolates of EV71 were amplified in Vero cells and used to challenge adult mice via hydrodynamic injection (HI) and intraperitoneal injection (IP). Following two challenges, >50% of the mice succumbed to EV71 infection. Surviving female mice were identified to have impaired fertility and their litter sizes were significantly decreased compared with the control group. The antibody against EV71-VP1 persisted in the sera of female mice at a high titer for >2 years after challenge. The maternal antibody in the offspring sera also persisted for ~1 year and disappeared after ~2 years. Results from the present study suggest that a high titer of active EV71 was able to impair the reproductivity of adult female mice, and that high levels of maternal antibody persisted in the offspring and protected postnatal mice from EV71-induced mortality. The promising antigenicity, immunogenicity and reactogenicity of EV71 suggests that it a potential vaccine target that may be beneficial to the control of HFMD, through immunizing infants and women of reproductive age.

Prognostic role of the long non-coding RNA, SPRY4 Intronic Transcript 1, in patients with cancer: a meta-analysis.

Recent studies have emphasized the important role of long non-coding RNAs (lncRNAs) in cancer development. The present study performed a meta-analysis to investigate whether lncRNA, SPRY4 Intronic Transcript 1(SPRY4-IT1) can be served as a potential biomarker for prognosis in human cancers. The eligible studies were collected by searching multiple online databases (Pubmed, EMBASE, CNKI, Web of Science and Google Scholar) and meta-analysis was performed to explore the association between the expression levels of SPRY4-IT1 and overall survival (OS), disease-free survival (DFS) and clinicopathological parameters. A total of 1329 patients from 13 studies were included for meta-analysis. The meta-analysis results showed that high expression level of SPRY4-IT1 was significantly associated with shorter OS in cancer patients (HR = 3.20, 95% CI: 2.59-3.90, P<0.001) except in the patients with non-small cell lung cancer (NSCLC). Increased SPRY4-IT1 expression level was correlated with shorter DFS in patients with gastric cancer and ovarian cancer. SPRY4-IT1 expression level was not correlated with the clinicopathological parameters including age (P = 0.37), gender (P = 0.87), tumor size (P = 0.47) and invasion depth (P = 0.52), and increased SPRY4-IT1 expression level was significantly associated with distant metastasis (odds ratio (OR) = 1.96, 95% CI: 1.24-3.08, P = 0.004), lymph node metastasis (OR = 3.96, 95% CI: 1.48-5.54, P<0.001), advanced tumor/node/metastasis stage (OR = 3.72, 95% CI = 2.91-4.76, P<0.001) and poor tumor differentiation (OR = 1.86, 95% CI = 1.35-2.58, P<0.001) in cancer patients except in patients with NSCLC. In summary, the meta-analysis results suggested that increased expression level of SPRY4-IT1 was positively associated with unfavorable prognosis and advanced features of cancers in cancer patients but not in patients with NSCLC.

Feedback regulation of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 via ATM/Chk2 pathway contributes to the resistance of MCF-7 breast cancer cells to cisplatin.

The methyl methanesulfonate and ultraviolet-sensitive gene clone 81 protein is a structure-specific nuclease that plays important roles in DNA replication and repair. Knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 has been found to sensitize cancer cells to chemotherapy. However, the underlying molecular mechanism is not well understood. We found that methyl methanesulfonate and ultraviolet-sensitive gene clone 81 was upregulated and the ATM/Chk2 pathway was activated at the same time when MCF-7 cells were treated with cisplatin. By using lentivirus targeting methyl methanesulfonate and ultraviolet-sensitive gene clone 81 gene, we showed that knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 enhanced cell apoptosis and inhibited cell proliferation in MCF-7 cells under cisplatin treatment. Abrogation of ATM/Chk2 pathway inhibited cell viability in MCF-7 cells in response to cisplatin. Importantly, we revealed that ATM/Chk2 was required for the upregulation of methyl methanesulfonate and ultraviolet-sensitive gene clone 81, and knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 resulted in inactivation of ATM/Chk2 pathway in response to cisplatin. Meanwhile, knockdown of methyl methanesulfonate and ultraviolet-sensitive gene clone 81 activated the p53/Bcl-2 pathway in response to cisplatin. These data suggest that the ATM/Chk2 may promote the repair of DNA damage caused by cisplatin by sustaining methyl methanesulfonate and ultraviolet-sensitive gene clone 81, and the double-strand breaks generated by methyl methanesulfonate and ultraviolet-sensitive gene clone 81 may activate the ATM/Chk2 pathway in turn, which provide a novel mechanism of how methyl methanesulfonate and ultraviolet-sensitive gene clone 81 modulates DNA damage response and repair.

NTN4 is associated with breast cancer metastasis via regulation of EMT-related biomarkers.

Metastasis is the leading cause of death for breast cancer patients. Nerve guidance factor 4 (Netrin-4, NTN4) is reduced in variety of malignancies and involved in tumor metastasis. However, the functions of NTN4 and related molecular mechanisms in breast cancer are poorly understood. Oncomine data revealed that NTN4 was decreased in breast cancer compared with normal breast tissues. For fresh frozen breast cancer samples, significantly depressed expression of NTN4 mRNA was observed in lesion tissues compared with that in adjacent tissues. Afterwards, NTN4 protein level was evaluated in 52 paired breast cancer tissues, and the results were consistent with that in fresh frozen samples. NTN4 expression was upregulated using NTN4-pcDNA3.1 plasmid in MDA-MB-231 cells and silenced using NTN4 small interfering RNA (siRNA) in Hs578T cells. Then the effects of NTN4 overexpression or knockdown on breast cancer cell migration and invasion were investigated. The results manifested that NTN4 overexpression attenuated cell migration and invasion, and induced N-cadherin and vimentin downregulation, while NTN4 siRNA-transfected cells had a significant increase in migration and invasion, as well as upregulation in N-cadherin and vimentin expression. These results demonstrate that NTN4 is reduced in breast cancer tissues and NTN4 is associated with breast cancer cell migration and invasion via regulation of epithelial mesenchymal transition (EMT)-related biomarkers.

[Circulating miR-152 helps early prediction of postoperative biochemical recurrence of prostate cancer].

OBJECTIVE: To investigate the value of circulating miR-152 in the early prediction of postoperative biochemical recurrence of prostate cancer. METHODS: Sixty-six cases of prostate cancer were included in this study, 35 with and 31 without biochemical recurrence within two years postoperatively, and another 31 healthy individuals were enrolled as normal controls. The relative expression levels of circulating miR-152 in the serum of the subjects were detected by qRT-PCR, its value in the early diagnosis of postoperative biochemical recurrence of prostate cancer was assessed by ROC curve analysis, and the correlation of its expression level with the clinicopathological parameters of the patients were analyzed. RESULTS: The expression of circulating miR-152 was significantly lower in the serum of the prostate cancer patients than in the normal controls (t = －5.212, P = 0.001), and so was it in the patients with than in those without postoperative biochemical recurrence (t = －5.727, P = 0.001). The ROC curve for the value of miR-152 in the early prediction of postoperative biochemical recurrence of prostate cancer showed the area under the curve (AUC) to be 0.906 (95% CI: 0.809－0.964), with a sensitivity of 91.4% and a specificity of 80.6%. The expression level of miR-152 was correlated with the Gleason score, clinical stage of prostate cancer, biochemical recurrence, and bone metastasis (P <0.05), decreasing with increased Gleason scores and elevated clinical stage of the malignancy. No correlation, however, was found between the miR-152 expression and the patients' age or preoperative PSA level (P >0.05). CONCLUSIONS: The expression level of circulating miR-152 is significantly reduced in prostate cancer patients with biochemical recurrence after prostatectomy and could be a biomarker in the early prediction of postoperative biochemical recurrence of the malignancy.

Clinical value of serum trophoblast cell surface protein 2 (TROP2) antibody in non-small-cell lung cancer patients.

OBJECTIVE: This study was to explore the clinical role of serum trophoblast cell surface protein 2 (TROP2) antibody in patients with non-small-cell lung cancer (NSCLC). MATERIALS AND METHODS: We collected serum specimens from 117 NSCLC patients, 40 benign lung disease patients, and 60 healthy controls. TROP2 antibody concentrations were measured using enzyme-linked immunosorbent assay. RESULTS: Serum TROP2 antibody levels were higher in the NSCLC group compared to the control group (p < 0.001). TROP2 antibody, at a cutoff value of 9.8 U/ml, showed good diagnostic performance for NSCLC. CONCLUSION: Measurement of TROP2 antibody might have diagnostic value for patients with NSCLC.

Effect of GEN1 interference on the chemosensitivity of the breast cancer MCF-7 and SKBR3 cell lines.

Chemotherapy is a notable method for the treatment of breast cancer. Numerous genes associated with the sensitivity of cancer to chemotherapy have been found. In recent years, evidence has suggested that a particular structure termed Holliday junction (HJ) plays a crucial role in cancer chemosensitivity. Targeting HJ resolvases, such as structure-specific endonuclease subunit SLX4 (Slx4) and MUS81 structure-specific endonuclease subunit (Mus81), significantly increases the chemosensitivity of tumor cells. Flap endonuclease GEN homolog 1 (GEN1) is a HJ resolvase that belongs to the Rad2/xeroderma pigmentosum complementation group G nuclease family. Whether GEN1 affects the chemosensitivity of tumor cells in a similar manner to Slx4 and Mus81 remains unknown. The aim of the present study was to determine the effect of GEN1 interference on the chemosensitivity of breast cancer cell lines. The investigation of the function of GEN1 was performed using MCF-7 and SKBR3 cells. Short hairpin RNA was used to suppress the expression of GEN1, and western blot analysis and reverse transcription-quantitative polymerase chain reaction were used to detect gene expression. In addition, a cell counting kit-8 assay was performed to detect the viability of cells and flow cytometry was performed to test apoptosis levels. Suppression of GEN1 in SKBR3 cells effectively increased the sensitivity to the chemotherapeutic drug 5-fluorouracil (5-FU), while MCF-7 cells showed no significant change in sensitivity following GEN1 suppression. However, when GEN1 was targeted in addition to Mus81, the MCF-7 cells also demonstrated a significantly increased sensitivity to 5-FU. In addition, when the level of Mus81 was low, GEN1 expression was increased under a low concentration of 5-FU. The present results suggest that GEN1 may play different roles in different breast cancer cell lines. The function of GEN1 may be affected by the level of Mus81 in the cell line. In addition, GEN1 interference may improve the sensitivity to chemotherapy induced by targeting Mus81 alone.