Chirality Gearing in an Achiral Cage through Adaptive Binding.

Herein we report an adaptive, achiral trithiourea molecular cage and its conformational and stereodynamics toward tricarboxylate anion binding. The cage was readily synthesized in four steps with a 44% yield for the irreversible cage-forming reaction. It possesses a flexible conformation and strongly binds 1,3,5-benzene tricarboxylate by forming a sandwich-like inclusion complex, with an affinity up to 106 M-1 in acetonitrile. Upon binding, the cage is locked in a twisted helical conformation. By incorporation of three chiral arms on the guest, a gear-like complex dominant in one given helical sense was produced. Due to the steric crowding in the helical grooves, a small change of methyl to ethyl on guest caused a striking difference on binding and chiral induction. The system thus represents a rare example of chiral induction on a flexible, achiral host and provides a decoupled model that the generation of a racemate and following chiral discrimination can be individually probed.

Beyond a tumor suppressor: Soluble E-cadherin promotes the progression of cancer.

E-cadherin (E-cad) plays important roles in tumorigenesis as well as in tumor progression, invasion and metastasis. This protein exists in two forms: a membrane-tethered form and a soluble form. Full-length E-cad is membrane tethered. As a type I transmembrane glycoprotein, E-cad mainly mediates adherens junctions between cells and is involved in maintaining the normal structure of epithelial tissues. Soluble E-cad (sE-cad) is the extracellular fragment of the protein that is cleaved from the membrane after proteolysis of full-length E-cad. The production of sE-cad undermines adherens junctions, causing a reduction in cell aggregation capacity; furthermore, sE-cad can diffuse into the extracellular environment and the blood. As a paracrine/autocrine signaling molecule, sE-cad activates or inhibits multiple signaling pathways and participates in the progression of various types of cancer, such as breast cancer, ovarian cancer, and lung cancer, by promoting invasion and metastasis. This article briefly reviews the role of sE-cad in tumorigenesis and tumor progression and its significance in clinical therapeutics.

[Haplotype analysis for mucocutaneous venous malformations in a Chinese Han ethnic family].

A Chinese Han ethnic family with mucocutaneous venous malformations (VMCM) was investigated. This family has autosomal dominantly inherited VMCM in five generations, and the offspring has a 50% risk of this inherited disorder. Affected individuals have small, spongy, and multiple vascular lesions, which often locate in the skin, oral mucosa, and upper and lower extremities. None of the family members had gastrointestinal bleeding, central nervous system involvement and cardiac defects. Pathological analysis showed that the veins have irregular vascular space and walls with variable thickness. All phenotypes of the patients displayed the basic characters of VMCM. To analyze the genetic locus and haplotype, genomic DNA of 26 family members was obtained from peripheral leukocytes, and the linkage analysis and haplotypes analysis were performed using microsatellites markers. The results of two-point linkage analysis and haplotype analysis showed that the disease-causing gene located within a 7 cM region between D9S1121 and D9S161 on the short arm of chromosome 9. The study firstly reported the Chinese family with VMCM, which disease-causing gene is located in 9p, consistent with western VMCM families reported. Four flanking markers, D9S1121, D9S169, D9S16 and D9S248, were used to define the linkage haplotypes in the family, which can provide useful informaion for researchers to study VMCM in different racial background.

Electroacupuncture Activates Neuroplasticity in the Motor Cortex and Corticospinal Tract via the mTOR Pathway in a Rat P-MCAO Model.

Electroacupuncture (EA) combines traditional Chinese medicine acupuncture theory with modern scientific technology. It is a promising therapy for the treatment of cerebrovascular diseases such as cerebral infarction. A large number of clinical studies have shown that EA promotes recovery of neurological function after cerebral infarction, however, the underlying mechanisms behind its effects remain unclear. We tested whether EA stimulation of the Zusanli (ST36) and Neiguan (PC6) acupoints activates neuroplasticity in rats with ischemic stroke and whether this involves the regulation of axonal regeneration through the mTOR pathway. 24 h after permanent middle cerebral artery occlusion (p-MCAO) in rats, EA treatment was started for 20 min, daily, for 14 days. We found that EA significantly reduced Modified Neurological Severity Scores (mNSS), cerebral infarct volume, and apoptosis of neuronal cells. EA also significantly increased the expression of the neuroplasticity-associated proteins GAP-43 and SYN and upregulated the phosphorylation levels of AKT, mTOR, S6, and PTEN to promote CST axon sprouting in the spinal cord at C1-C4 levels. The positive effects of EA were blocked by the administration of the mTOR inhibitor Rapamycin. In short, we found that EA of the Zusanli (ST36) and Neiguan (PC6) acupoints in p-MCAO rats induced neuroprotective and neuroplastic effects by regulating the mTOR signaling pathway. It promoted neuroplasticity activated by axon regeneration in the contralateral cortex and corticospinal tract. Activation of such endogenous remodeling is conducive to neurological recovery and may help explain the positive clinical effects seen in patients with infarcts.

Prognostic alternative splicing signature in cervical squamous cell carcinoma.

Basing on alternative splicing events (ASEs) databases, the authors herein aim to explore potential prognostic biomarkers for cervical squamous cell carcinoma (CESC). mRNA expression profiles and relevant clinical data of 223 patients with CESC were obtained from The Cancer Genome Atlas (TCGA). Correlated genes, ASEs and percent-splice-in (PSI) were downloaded from SpliceSeq, respectively. The PSI values of survival-associated alternative splicing events (SASEs) were used to construct the basis of a prognostic index (PI). A protein-protein interaction (PPI) network of genes related to SASEs was generated by STRING and analysed with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Consequently, 41,776 ASEs were discovered in 19,724 genes, 2596 of which linked with 3669 SASEs. The PPI network of SASEs related genes revealed that TP53 and UBA52 were core genes. The low-risk group had a longer survival period than high-risk counterparts, both groups being defined according to PI constructed upon the top 20 splicing events or PI on the overall splicing events. The AUC value of ROC reached up to 0.88, demonstrating the prognostic potential of PI in CESC. These findings suggested that ASEs involve in the pathogenesis of CESC and may serve as promising prognostic biomarkers for this female malignancy.

[Gene diagnosis and CAG repeat analysis of spinocerebellar ataxia cases of Guangxi region].

To characterize the distributions and subtypes of the spinocerebellar ataxias (SCA) in Guangxi region, the SCAl, SCA2, SCA3/MJD, SCA6, SCA7 and SCA12 (CAG)n mutations were analyzed by polymerase chain reaction (PCR) and capillary electrophoresis (CE). The SCA3/MJD mutation was detected in a total of 21 SCA patients and 19 presymptomatic individuals from 6 SCA families and their CAG repeat numbers were 59-70 and 60-73, respectively. No (CAG)n mutations of SCA1, SCA2, SCA6, SCA7 and SCA12 were detected. This study showed that SCA in Guangxi region is mostly SCA3/MJD subtype and the CAG repeats are smaller than those reported in other regions previously.

Construction of a model to predict the prognosis of patients with cholangiocarcinoma using alternative splicing events.

Cholangiocarcinoma (CCA) is a type of malignant tumor that originates in the mucosal epithelial cells of the biliary system. It is a highly aggressive cancer that progresses rapidly, has low surgical resection rates and a high recurrence. At present, no prognostic molecular biomarker for CCA has been identified. However, CCA progression is affected by mRNA precursors that modify gene expression levels and protein structures through alternative splicing (AS) events, which create molecular indicators that may potentially be used to predict CCA outcomes. The present study aimed to construct a model to predict CCA prognosis based on AS events. Using prognostic data available from The Cancer Genome Atlas, including the percent spliced index of AS events obtained from TCGASpliceSeq in 32 CCA cases, univariate and multivariate Cox regression analyses were performed to assess the associations between AS events and the overall survival (OS) rates of patients with CCA. Additional multivariate Cox regression analyses were used to identify AS events that were significantly associated with prognosis, which were used to construct a prediction model with a prognostic index (PI). A receiver operating characteristic (ROC) curve was used to determine the predictive value of the PI, and Pearson's correlation analysis was used to determine the association between OS-related AS events and splicing factors. A total of 38,804 AS events were identified in 9,673 CCA genes, among which univariate Cox regression analysis identified 1,639 AS events associated with OS (P<0.05); multivariate Cox regression analysis narrowed this list to 23 CCA AS events (P<0.001). The final PI model was constructed to predict the survival of patients with CCA; the ROC curve demonstrated that it had a high predictive power for CCA prognosis, with a highest area under the curve of 0.986. Correlations between 23 OS-related AS events and splicing factors were also noted, and may thus, these AS events may be used to improve predictions of OS. In conclusion, AS events exhibited potential for predicting the prognosis of patients with CCA, and thus, the effects of AS events in CCA required further examination.

Upregulation of miR­132­3p in cholangiocarcinoma tissues: A study based on RT­qPCR, The Cancer Genome Atlas miRNA sequencing, Gene Expression Omnibus microarray data and bioinformatics analyses.

MicroRNAs (miRNAs/miRs) have been reported to be closely associated with numerous human diseases, including cholangiocarcinoma (CCA). However, the number of miRNAs known to be involved in CCA is limited, and the association between miR­132­3p and CCA remains unknown. In the present study, the clinical role of miR­132­3p and its potential signaling pathways were investigated by multiple approaches. Reverse transcription­quantitative PCR (RT­qPCR), CCA­associated Gene Expression Omnibus (GEO), ArrayExpress and Sequence Read Archive (SRA) miRNA­microarray or miRNA­sequencing data were screened, and meta­analyses were conducted, in order to calculate the receiver operating characteristic (ROC) curve and standardized mean difference (SMD). The predicted target genes of miR­132­3p were obtained from 12 online databases and were combined with the downregulated differentially expressed genes identified in the RNA­sequencing data of CCA. Gene Ontology annotation and pathway analysis were performed in WebGestalt. Protein­protein interaction analyses were conducted in STRING. The Cancer Genome Atlas (TCGA) mRNA expression profiles were used to validate the expression levels of hub genes at the mRNA level. The Human Protein Atlas was used to identify the protein expression levels of hub genes in CCA tissues and non­tumor biliary epithelium. The meta­analyses comprised 10 groups of RT­qPCR data, eight GEO microarray datasets and one TCGA miRNA­sequencing dataset. The SMD of miR­132­3p in CCA was 0.75 (95% CI: 0.25, 1.24), which indicated that miR­132­3p was overexpressed in CCA tissues. This finding was supported by a summary ROC value of 0.80 (95% CI: 0.76, 0.83). The pooled sensitivity and specificity were 0.81 (95% CI: 0.59, 0.93) and 0.71 (95% CI: 0.58, 0.81), respectively. The relative expression level of miR­132­3p in the early stage of CCA (stages I­II) was 6.8754±0.5279, which was markedly lower than that in the advanced stage (stages III­IVB), 7.3034±0.3267 (P=0.003). Consistently, the miR­132­3p level in low­grade CCA (grades G1­G2) was 6.7581±0.5297, whereas it was 7.1191±0.4651 in patients with high­grade CCA (grades G3­G4) (P=0.037). Furthermore, 555 potential target genes of miR­132­3p in CCA were mainly enriched in the 'Focal Adhesion­PI3K­Akt­mTOR­signaling pathway'. In conclusion, upregulation of miR­132­3p may serve a pivotal role in the tumorigenesis and progression of CCA by targeting different pathways. Further in vitro and in vivo studies are required to support the current findings.

Down-regulation of cancer/testis antigen OY-TES-1 attenuates malignant behaviors of hepatocellular carcinoma cells in vitro.

Cancer/testis (CT) antigens are normally expressed in testis and overexpressed in various tumor types. However, their biological function is largely unknown. OY-TES-1, one of cancer/testis (CT) antigens, is reported overexpression in hepatocellular carcinoma (HCC). And we assumed that OY-TES-1 contribute to oncogenesis and progression of HCC. In this study, we knocked down OY-TES-1 by small interference RNA (siRNA) in HCC cell lines (HepG2 and BEL-7404) to verify this assumption and evaluate its potential as therapeutic targets for HCC. We showed that down regulation of OY-TES-1 decreased cell growth, induced the G0/G1 arrest and apoptosis, and prevented migration and invasion in the two HCC cell lines. Further analysis revealed that down regulation of OY-TES-1 increased expression of apoptosis-regulated protein caspase-3, and decreased expression of cell cycle-regulated protein cyclin E, migration/invasion-regulated proteins MMP2 and MMP9. These findings may shed light on the gene therapy about the OY-TES-1 expression in HCC cells.

Distinct patterns of ALDH1A1 expression predict metastasis and poor outcome of colorectal carcinoma.

PURPOSE: Aldehyde dehydrogenase 1A1 (ALDH1A1) has been proposed as a candidate biomarker for colorectal carcinoma (CRC). However, the heterogeneity of its expression makes it difficult to predict the outcome of CRC. The aim of this study was to evaluate the diagnostic and prognostic value of this molecule in CRC. METHODS AND RESULTS: In this study, we examined ALDH1A1 expression by immunohistochemistry including 406 cases of primary CRC with corresponding adjacent mucosa, with confirmation of real-time PCR and Western blotting. We found that the expression patterns of ALDH1A1 were heterogeneous in the CRC and corresponding adjacent tissues. We defined the ratio of ALDH1A1 level in adjacent mucosa to that in tumor tissues as RA/C and found that the capabilities of tumor invasion and metastasis in the tumors with RA/C < 1 were significantly higher than those with RA/C ≥ 1. Follow-up data showed the worse prognoses in the CRC patients with RA/C < 1. For understanding the underlying mechanism, the localization of ß-catenin was detected in the CRC tissues with different patterns of ALDH1A1 expression from 221 patients and ß-catenin was found preferentially expressed in cell nuclei of the tumors with RA/C < 1 and ALDH1A1(high) expression of HT29 cell line, indicating that nuclear translocation of ß-catenin might contribute to the increased potentials of invasion and metastasis. CONCLUSION: Our results indicate that RA/C is a novel biomarker to reflect the distinct expression patterns of ALDH1A1 for predicting metastasis and prognosis of CRC.