Biomedical subjects

Yue Zhou

Publications and source records attributed to Yue Zhou.

At least 19 recordsLinked to original sources

PubMed2026

Decoding age-stratified clinical and molecular heterogeneity in male breast cancer through multiomic profiling.

OBJECTIVE: Age-associated molecular heterogeneity is well described in female breast cancer but remains insufficiently characterized in male breast cancer (MBC). We profiled age-stratified clinical and molecular differences between younger (≤55 years) male breast cancer (YMBC) and older (>55 years) male breast cancer (OMBC). METHODS: We retrospectively analyzed 347 patients with MBC diagnosed at Fudan University Shanghai Cancer Center by integrating clinicopathological data, RNA sequencing, and whole-exome sequencing (WES). Survival, differential expression, and mutational signature analyses were performed. Tumor microenvironment features were inferred using xCell and ESTIMATE, and weighted gene co-expression network analysis (WGCNA) was conducted to identify age-associated co-expression modules. Candidate therapeutics were prioritized using the Genomics of Drug Sensitivity in Cancer (GDSC) resource and evaluated using patient-derived organoids (PDOs). RESULTS: Compared with OMBC, YMBC more frequently had human epidermal growth factor receptor 2 (HER2)-positive status (14.91% vs. 4.02%) and triple-negative tumors (4.92% vs. 1.78%), and had worse 5-year recurrence-free survival (hazard ratio=2.19, P=0.018). Transcriptomic analyses indicated enrichment of neural-related programs and reduced immune-related signaling in YMBC, and xCell/ESTIMATE supported lower immune infiltration. Consistently, WGCNA identified age-associated modules linking neural-related programs with reduced immune infiltration. Immunohistochemistry supported increased perineural invasion and lower CD8+ T cell infiltration in YMBC. GDSC-guided prioritization with PDO testing nominated sepantronium bromide (YM155) as a candidate vulnerability in YMBC. WES showed a higher NBPF10 mutation frequency in YMBC (54.5% vs. 14.3%, P<0.05). CONCLUSIONS: Integrated multi-omics profiling revealed age-stratified clinical and molecular heterogeneity in MBC. YMBC patients demonstrated inferior recurrence-free survival, neural signaling enrichment, an immune-cold microenvironment, and enriched NBPF10 mutations. These findings support age as a meaningful stratification variable in MBC risk assessment and treatment planning, and highlight the need for caution when considering treatment de-escalation in younger patients, while nominating YM155 as a candidate agent for prospective evaluation.

Male breast cancer↗

PubMed2026

Clinical relevance of HRD score in pheochromocytomas and paragangliomas: molecular cluster distribution and prognostic implications.

Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors with variable metastatic potential across molecular clusters. While the homologous recombination deficiency (HRD) score has been established as a surrogate for HRD-related genomic instability to guide prognostic evaluation and therapeutic options in multiple solid tumors, its relevance in PPGLs remains unexplored. Here, data from 133 PPGL patients in the TCGA database were extracted to assess relationships between the HRD score and molecular clusters, metastasis, metastasis-free survival (MFS), and other clinical characteristics. Subsequently, a real-world cohort of 54 matched blood-tumor pairs was subjected to whole-exome sequencing, with HRD scores calculated to confirm the prior observations. The median HRD score was 7.0 and 9.0 in the TCGA-PPGL dataset and the clinical cohort, respectively. In the TCGA dataset, an elevated HRD score significantly correlated with metanephrine secretion, C2 cluster, and metastasis. Multivariate analysis identified a higher HRD score as an independent risk factor for shorter MFS (HR = 1.33, P = 0.008). Patients with HRD scores ≥ 7 exhibited significantly shorter MFS (P = 0.037), which was observed exclusively within the C1A cluster (P = 0.007). Analyses of our clinical validation cohort corroborated this cluster-specific distribution and further revealed higher HRD scores in three temozolomide-treated PPGLs compared with those treatment-naive C1A tumors (P = 0.043). In conclusion, despite exhibiting lower levels in C1A clusters, an elevated HRD score emerges as a promising indicator for refined metastatic risk stratification in PPGLs. Futhermore, the substantial increase in HRD score following temozolomide treatment provides a rationale for PARP inhibitor sequential or combination therapy in metastatic PPGLs.

Humans↗

PubMed2026

Genetically predicted associations between blood cell perturbation responses and bronchiectasis through immune mediation: A Mendelian Randomization study.

BACKGROUND: Bronchiectasis is a chronic airway disease characterized by persistent inflammation and structural damage, with substantial clinical and etiologic heterogeneity. Although previous studies have identified associations between blood cells and bronchiectasis, the causal relationships remain unclear. Moreover, the mechanisms underlying blood cell perturbation responses and their potential mediation by immune cells in disease progression are largely unexplored. METHODS: Two-sample Mendelian randomization (MR) analysis was used to explore genetically predicted associations among immune cell traits, blood cell perturbation response phenotypes, and bronchiectasis, based on genome-wide association study summary data. Mediation MR analysis was further applied to assess whether immune cells mediate these associations. Multiple sensitivity analyses, including tests for heterogeneity and horizontal pleiotropy, were performed to evaluate the validity and robustness. RESULTS: Five blood cell perturbation response phenotypes and twenty-nine immune cell traits showed significant genetically predicted associations with bronchiectasis. Mediation analysis showed that natural killer (NK) cell absolute count partially mediated the causal effect between the eosinophil perturbation response and bronchiectasis, with a mediation proportion of 9.626%. CD38 on transitional B cells mediated the causal effect between the monocyte perturbation response and bronchiectasis, with a mediation proportion of 10.580%. Additionally, CD45 on NK cells played a mediating role in the association between the white blood cell perturbation response and bronchiectasis, with a mediation proportion of 10.651%. CONCLUSION: This study systematically explores genetically predicted associations between blood cell perturbation responses and bronchiectasis and highlights potential immune-mediated pathways. These exploratory findings provide novel genetic insights into the pathogenesis of bronchiectasis and identify potential therapeutic targets for future strategies.

Humans↗

PubMed2025

FOSB is a key factor in the genetic link between inflammatory bowel disease and acute myocardial infarction: multiple bioinformatics analyses and validation.

BACKGROUND: Inflammatory Bowel Disease (IBD), which includes Crohn's disease and ulcerative colitis, is associated with an increased risk of Acute Myocardial Infarction (AMI). The genetic mechanisms underlying this link are not well understood. METHODS: We downloaded IBD and AMI-related microarray datasets from the NCBI Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were identified and analyzed using enrichment analysis and Weighted Gene Co-expression Network Analysis (WGCNA). Machine learning techniques, including LASSO, random forest, and Boruta, were employed to screen for hub genes. These genes were validated through qRT-PCR and Western blotting. Single-cell sequencing was used to confirm findings. Additionally, potential therapeutic targets were identified using the Connectivity Map (CMap) database. RESULTS: Five key hub genes-THBD, FOSB, ADGPR3, IL1R2, and PLAUR-were identified as significantly involved in both IBD and AMI pathogenesis. A diagnostic model for AMI constructed using these hub genes demonstrated high predictive accuracy. Single-cell sequencing analysis and several potential drugs targeting these hub genes were identified, offering new therapeutic avenues. CONCLUSION: This study highlights the crucial role of FOSB and other hub genes in the comorbidity of IBD and AMI. The findings provide novel insights for early diagnosis and potential therapeutic strategies, emphasizing the importance of further investigation into these genetic links.

Humans↗

PubMed2016

Matrix stiffness promotes cartilage endplate chondrocyte calcification in disc degeneration via miR-20a targeting ANKH expression.

The mechanical environment is crucial for intervertebral disc degeneration (IDD). However, the mechanisms underlying the regulation of cartilage endplate (CEP) calcification by altered matrix stiffness remain unclear. In this study, we found that matrix stiffness of CEP was positively correlated with the degree of IDD, and stiff matrix, which mimicked the severe degeneration of CEP, promoted inorganic phosphate-induced calcification in CEP chondrocytes. Co-expression analysis of the miRNA and mRNA profiles showed that increasing stiffness resulted in up-regulation of miR-20a and down-regulation of decreased ankylosis protein homolog (ANKH) during inorganic phosphate-induced calcification in CEP chondrocytes. Through a dual luciferase reporter assay, we confirmed that miR-20a directly targets 3'-untranslated regions of ANKH. The inhibition of miR-20a attenuated the calcium deposition and calcification-related gene expression, whereas the overexpression of miR-20a enhanced calcification in CEP chondrocytes on stiff matrix. The rescue of ANKH expression restored the decreased pyrophosphate efflux and inhibited calcification. In clinical samples, the levels of ANKH expression were inversely associated with the degeneration degree of CEP. Thus, our findings demonstrate that the miR-20a/ANKH axis mediates the stiff matrix- promoted CEP calcification, suggesting that miR-20a and ANKH are potential targets in restraining the progression of IDD.

3' Untranslated Regions↗

PubMed2006

Blockage of oncostatin M-induced LDL receptor gene transcription by a dominant-negative mutant of C/EBPbeta.

OM (oncostatin M) activates the human LDLR [LDL (low-density lipoprotein) receptor] gene transcription in HepG2 cells through the SIRE (sterol-independent regulatory element) of LDLR promoter. The SIRE sequence consists of a C/EBP (CCAAT/enhancer-binding protein)-binding site and a CRE (cAMP-response element). Our previous studies [Zhang, Ahlborn, Li, Kraemer and Liu (2002) J. Lipid Res. 43, 1477-1485; Zhang, Lin, Abidi, Thiel and Liu (2003) J. Biol. Chem. 278, 44246-44254] have demonstrated that OM transiently induces EGR-1 (early growth response gene product 1) expression and EGR-1 activates LDLR transcription primarily through a protein-protein interaction with C/EBPbeta, which serves as a co-activator of EGR-1. In the present study, we examined the direct role of C/EBPbeta as a transactivator in OM-regulated LDLR gene transcription independent of EGR-1. We show that OM induces C/EBPbeta expression with kinetics slower than EGR-1 induction. A significant increase in C/EBPbeta protein level is detected by 2 h of OM treatment and remains elevated for 24 h. Chromatin immunoprecipitation assays demonstrate that the amount of C/EBPbeta bound to the LDLR SIRE sequence is increased 2.8-fold of control by 2 h of OM treatment, reached the highest level of 8-fold by 4 h, and slowly declined thereafter. To further examine the requirement of C/EBPbeta in OM-stimulated LDLR expression, we developed a His-tagged dominant-negative mutant of C/EBPbeta (His-C/EBPbeta-P4; where P4 is plasmid 4 in our mutation series), consisting of the DNA-binding and leucine zipper domains of C/EBPbeta (amino acids 246-345). Expression of His-C/EBPbeta-P4 in HepG2 cells significantly diminishes the OM-induced increase in LDLR promoter activity and the elevation of endogenous LDLR mRNA expression. Taken together, these new findings identify C/EBPbeta as an OM-induced transactivator in LDLR gene transcription and provide a better understanding of the molecular mechanism underlying the sterol-independent regulation of LDLR expression.

Antineoplastic Agents↗

PubMed2006

Evidence for long poly(dA).poly(dT) tracts in D. discoideum DNA at high frequencies and their preferential avoidance of nucleosomal DNA core regions.

The eukaryote, Dictyostelium discoideum, has one of the most (A+T) rich genomes studied to date. Isolated nuclear D. discoideum DNA (AX3 strain) was used to qualitatively determine the frequency and length distribution of long (dA).(dT) homopolymer tracts in this genome, in comparison to the less (A+T) rich calf thymus and Schistosoma mansoni DNAs that had few observable long tracts. These experimental data accurately reflect the significantly elevated frequencies of long tracts found computationally within the D. discoideum intron and flanking sequences, but not exons. PCR amplification of long (dA).(dT) homopolymer tract containing sequences was carried out. Then experimental biotinylated (dT)18 probe hybridization to the PCR amplified DNA showed that the long (dA).(dT) homopolymer tracts were enriched in D. discoideum sequences only hundreds of base pair in length, under conditions where no equivalent hybridization was observed to S. mansoni DNA or calf DNA sequences. Similar probe hybridization to DNA isolated following micrococcal nuclease digestion of D. discoideum chromatin demonstrated that long (dA).(dT) homopolymer tracts were more highly enriched in nucleosomal DNA lengths that included the internucleosomal linker as compared to shorter linker free mononucleosomal lengths. This observation is in agreement with the frequency of tract spacing results calculated from GenBank sequence data. These frequency data indicate that adjacent long tracts plus the intervening spacer DNA are found at peak lengths (average 42 bp), exactly characteristic of the internucleosomal spacer region of D. discoideum chromatin and are in sufficient number to be found in nearly half of all nucleosomes. Compared to shuffled tract sequence controls, these lengths of adjacent long tracts plus the intervening spacer DNA were found to be significantly enriched. Lesser enrichments are observed at lengths corresponding to adjacent tracts being separated by nucleosomal core length DNA sequences (145-185 bp). These data strongly suggest that adjacent long tracts occur spaced at selected lengths so as to avoid the central core regions of nucleosomes and instead are found localized within internucleosomal DNA linker and core edge regions in D. discoideum chromatin.

Animals↗

PubMed2006

[Application of enhanced green fluorescent protein labeling technology to monitoring marrow mesenchymal stem cells migration after bone fracture].

OBJECTIVE: To monitor the stem cell migration into the bone defect following an injection of the labeled mesenchymal stem cells (MSCs) by the enhanced green fluorescent protein (EGFP) technology and to provide insights into an application of MSCs for the fracture healing. METHODS: Isolated MSCs from the rabbit femur marrow were culture-expanded and were labeled by the transfection with the recombinant retrovirus containing the EGFP gene. Then, some labeled MSCs were cultured under the osteogenic differentiation condition and the phenotype was examined. After the fracture of their bilateral ulna, 18 rabbits were divided into two groups. The labeled MSCs were injected into the aural vein at 1 x 10(7) cells/kg in the experimental group and the unmarked MSCs were injected in the control group 24 hours before surgery, and 1 and 24 hours after surgery, respectively. Necropsies were performed 2 days after surgery in the two groups. The sections from the left defects were observed under the fluorescence microscope and the others were analyzed by the bright-field microscopy after the HE staining. RESULTS: The EGFP did not affect the MSCs viability. After the labeled cells were incubated in the osteogenic medium alkaline phosphatase, the calcium nodules were observed. All the rabbits survived. The tissue of haematoma was observed in the bone defects and the fluorescent cells were found in the experimental group, but no fluorescent cells existed in the control group. CONCLUSION: The EGFP-labeled MSCs can undergo osteogenic differentiation in vitro and can migrate into bone defects after their being injected into the peripheral vein.

Animals↗

PubMed2006

[Effects of core binding factor alpha1 on promotion of osteoblastic differentiation from marrow mesenchymal stem cells].

OBJECTIVE: To observe effects of the core binding factor alpha1 (Cbfalpha1) in its promoting differentiation of the rabbit marrow mesenchymal stem cells (MSCs) into osteoblasts. METHODS: The rabbit marrow MSCs were isolated and cultured in vitro and were divided into 3 groups. In the control group, the marrow MSCs were cultured by DMEM; in the single inducement group, they were cultured by the condition medium (DMEM, 10% fetal bovine serum, dexamethasone 10 mmol/L, vitamin C 50 mg/L, and beta-GP 10 mmol/L); and in the experimental group, they were transfected with AdEasyl/Cbfalpha1, and then were cultured by the condition medium. The alkaline phosphatase (ALP) activity and the expression of osteocalcin as the osteoblast markers were measured with the chemohistological and immunohistochemical methods at 3 days, 1, 2, 3, and 4 weeks after inducement. RESULTS: More than 90% MSCs were grown well in vitro. The GFP was positive in MSCs after their being transfected with AdEasyl/Cbfalpha1. The ALP activity and the expression of osteocalcin were significantly upregulated in the transfection group compared with those in the single inducement group and the control group at 1, 2, 3, and 4 weeks (P < 0.05). The mineralized node began to appear at 2 weeks in the experimental group and the single induction group, but did not appear in control group. CONCLUSION: Cbfalpha1 can obviously promote differentiation of the rabbit marrow mesenchymal stem cells into the osteoblasts.

Animals↗

PubMed2006

Abnormal activation of the synuclein-gamma gene in hepatocellular carcinomas by epigenetic alteration.

Liver cancer is the fifth most common neoplastic disease and the fourth leading cause of cancer-related death. Identification of the key molecular targets involved in hepatocarcinogenesis has significant therapeutic implications. In this study, by conducting immunohistochemistry, we show that the neuronal protein, synuclein-gamma (SNCG), is abnormally expressed in a high percentage of liver cancer (46/70, 65.7%). The expression of SNCG in liver cancer exhibits a clear stage-specific pattern of low expression in stage I (1/19, 5.3%) and high expression in stages III to IV (44/50, 88%). Importantly, all patients with metastatic diseases expressed SNCG in their primary tumors (15/15, 100%). Consistent with the IHC results, RT-PCR assays demonstrate that SNCG mRNA is highly expressed in the tumor tissue of advanced hepatocellular carcinomas. Analyses of the methylation status of the CpG island of the SNCG gene by methylation-specific PCR confirmed that all tumor samples contained the demethylated gene. To determine whether demethylation of SNCG is an early event of genetic abnormality in the process of hepatocarcinogenesis, we examined the methylation status of SNCG in 70 non-malignant cirrhotic liver samples and showed that 64.3% cirrhotic liver samples contained the partially or completely demethylated gene. We further show that SNCG expression in liver cancer is not restricted to HBV- and HCV-infected tumors, implying the involvement of other hepatocarcinogenic risk factors in SNCG gene reactivation. Utilizing human hepatoma-derived cell line HepG2 as an in vitro model, we demonstrate that hepatic carcinogens aflatoxin B1 and N-nitrosodimethylamine (DMN) are strong inducers of SNCG expression. Collectively, these new findings suggest that SNCG protein expression in primary tumors is a strong indicator of distant metastasis and demethylation of SNCG CpG island is an early sign of genetic abnormality in liver cirrhosis preceding hepatocarcinogenesis. Our studies also suggest that inducing demethylation of SNCG by hepatocarcinogens may represent one underlying mechanism for the aberrant expression of SNCG in HCC.

Adult↗

PubMed2006

Inhibition of synuclein-gamma expression increases the sensitivity of breast cancer cells to paclitaxel treatment.

Anti-microtubule drugs that cause mitotic arrest and subsequent apoptosis of cancer cells are frequently used to treat breast cancer patients with advanced or metastatic diseases. However, patient response rates to this class of chemotherapeutic agents vary significantly. Identification of cellular and genetic factors that are associated with the sensitivity to anti-microtubule drug treatment would have great clinical implications. Our previous studies have demonstrated that the neuronal protein, synuclein-gamma (SNCG), plays oncogenic roles in breast carcinogenesis and is abnormally expressed at high levels in advanced and metastatic breast carcinomas but not expressed in normal or benign breast tissues. In this study, we show that responses of 12 breast cancer cell lines to paclitaxel-induced mitotic arrest and cytotoxicity highly correlate with SNCG expression status. SNCG-positive cells exhibit a significant higher resistance to paclitaxel-induced mitotic arrest than SNCG-negative cells (p<0.01). Moreover, we demonstrate that down-regulation of SNCG expression directly increased the effectiveness of anti-microtubule drug-induced cytotoxicity in breast cancer cells without altering cell responses to doxorubicin. These new findings suggest that SNCG expression in breast carcinomas is probably a causal factor contributing to the poor patient response to paclitaxel treatment.

Antibiotics, Antineoplastic↗

PubMed2006

[Total hip arthroplasty for treatment of developmental dysplasia of the hip].

OBJECTIVE: To summarize the techniques of the total hip arthroplasty in the treatment of osteoarthritis secondary to developmental dysplasia of the hip joint (DDH). METHODS: Between February 1986 and November 2004, a total of 32 hips in 24 patients with advanced osteoarthritis secondary to DDH underwent the total hip arthroplasty. Among the patients, 4 were male and 20 were female, with their ages ranging from 33 to 59 years and an average age of 47 years. The bilateral arthroplasty was performed in 8 patients and the unilateral arthroplasty in 16 patients. The patients mainly suffered from pain and claudication. According to the Hartofilakidis classification, semidislocation occurred in 2 hips, low-dislocation in 21 hips, and high-dislocation in 9 hips; and the Harris scores before operation were 56.70 +/- 2.75, 36.09 +/- 4.16, and 29.45 +/- 2.16, respectively. RESULTS: All the patients were followed up for 6 months to 8 years (averaged 3 years and 4 months). The Harris scores after operation were 93.10 +/- 2.10, 92.7 +/- 3.20, and 88.09+/- 3.67, respectively. The differences between preoperation and postoperation were significant (P < 0.01). All the patients were pain-free and there was no sign of aseptic loosening and subsidence. CONCLUSION: The total hip arthroplasty is an effective method for the treatment of osteoarthritis secondary to DDH. The key techniques for the total hip arthroplasty are as follows: deepening the medial wall of the acetabulum, improving the techniques of the bone graft, and firmly placing the acetabular component in the true acetabulum.

Acetabulum↗

PubMed2006

[Study on several methods of character analysis and classification for pulse-condition based on statistics theory ].

In this paper, several methods of character analysis and classification for pulse condition are studied with the use of statistics theory. Five methods are applied to character abstraction. Pulse condition is analyzed in time, frequency and wavelet domain. The abstraction methods include wavelet analysis, AR modeling, and template match. On the other hand, four classification methods are used, namely BP, RBF, CGA and FMMNN.

Humans↗

PubMed2005

[The clinical comparison of microendoscopic lumbar diskectomy with and without preservation of the ligamentum flavum].

OBJECTIVE: To discuss the surgical technique, indication and the clinical effects of the Microscope Endoscopic Tubular Retractor System (METRx) for microendoscopic lumbar diskectomy with the preservation of the ligamentum flavum. METHODS: Two hundred and eleven patients underwent single-segment METRx, with ligamentum flavum preservation in 65 patients (Group A), and without preservation in 146 patients (Group B). The two groups were compared clinically. All the patients suffered from low back pain and radicular syndrome to some extent, and the diagnosis was affirmed by CT and/or MRI. After exposed the interlaminar space regularly, the superior, inferior and lateral edge of the ligamentum flavum was released, the 3-sided dissociative ligament pacth was retracted medially during the spinal manipulation and restored anatomically after disc removal and the decompression of the nerve root. RESULTS: According to the results of two groups, ligamentum flavum preservation technique was feasible under endoscope and helpful in reducing the scar formation in the spinal canal. CONCLUSIONS: The ligamentum flavum preservation technique enable the surgeons to preserve the natural barrier. It is feasible to perform METRx, and it is helpful in reducing the epidural fibrosis.

Adult↗

PubMed2005

Feasibility of tissue plasminogen activator formulated for pulmonary delivery.

PURPOSE: This study was conducted to assess the feasibility of a pulmonary formulation of tissue plasminogen activator (tPA) for nebulization into the airway by measuring protein stability, biologic activity, particle size, and estimating human lung distribution. METHODS: Formulations were derived by varying the surfactant and protein concentrations. Protein stability and recovery of each nebulized tPA formulation were assessed by ultraviolet spectroscopy. Formulations that met protein stability feasibility criteria were assessed for biologic and fibrinolytic activities. Biologic activity was determined by their ability to inhibit superoxide anion production by human neutrophils. Fibrinolytic activity was assessed by the cleavage of plasminogen to plasmin. Aerodynamic properties were assessed using a cascade impactor, and an estimation of human airway deposition was made via a human lung replica. RESULTS: Twenty-seven tPA formulations were initially assessed, 15 of which met protein stability criteria. Subsequently, three of these formulations maintained biologic and fibrinolytic activities. These formulations exhibited particle sizes of 2.4-3.1 microm, and had respirable doses > or =65%. A formulation of 1mg mL(-1) tPA and 0.1% Tween 80 exhibited a 45% deposition in the lower airways of a human lung replica. CONCLUSIONS: A suitable pulmonary tPA formulation was identified that, following nebulization, maintained protein stability as well as biologic and fibrinolytic activities, and resulted in an optimal respirable dose and human airway deposition. This formulation may be applicable in the treatment of lung diseases, such as acute respiratory distress syndrome by permitting targeted pulmonary delivery of a therapeutic protein to the lungs.

Chemistry, Pharmaceutical↗

PubMed2005

Loss of epigenetic control of synuclein-gamma gene as a molecular indicator of metastasis in a wide range of human cancers.

Metastasis is a major contributing factor to poor prognosis in cancer. Reliable and sensitive biomarkers that indicate the development of metastasis of primary tumors would be of great clinical use. In this study, we show that the neuronal protein synuclein-gamma (SNCG) is abnormally expressed in a high percentage (67.5%) of tumor tissues of diversified cancer types, including liver, esophagus, colon, gastric, lung, prostate, cervical, and breast cancer, but rarely expressed in tumor-matched nonneoplastic adjacent tissues (0.6%). Expressions of SNCG protein in different cancer types all display stage-specific patterns of very low expression in stage I and high expression in stages II to IV. Importantly, we observe a strong association between SNCG protein expression in primary tumors with distant metastasis in patients regardless of the cancer type (60.6%, P < 0.001). By performing genomic sequencing and methylation-specific PCR assays, we identify an inclusive demethylation of CpG sites within the CpG island of SNCG gene in every tumor sample (100%) across all cancer types, illustrating a universal loss of the epigenetic control of SNCG gene expression in tumors and further demonstrating that the demethylation of SNCG CpG island is primarily responsible for the aberrant expression of SNCG protein in cancerous tissues. These new findings strongly suggest that reactivation of SNCG gene expression by DNA demethylation is a common critical contributing factor to malignant progression of many solid tumors and its expression in primary carcinomas is an effective molecular indicator of distant metastasis. Our studies also suggest that the methylation status of SNCG gene can be used as a sensitive molecular tool in early detections of tumorigenesis.

Aged↗

PubMed2005

Extracellular signal-regulated kinase-dependent stabilization of hepatic low-density lipoprotein receptor mRNA by herbal medicine berberine.

OBJECTIVE: Our recent studies identified berberine (BBR) as a novel cholesterol-lowering drug that upregulates low-density lipoprotein (LDL) receptor expression through mRNA stabilization. Here, we investigated mechanisms underlying regulatory effects of BBR on LDL receptor (LDLR) messenger. METHODS AND RESULTS: We show that the extracellular signal-regulated kinase (ERK) signaling pathway is used primarily by BBR to attenuate the decay of LDLR mRNA in HepG2 cells. Using different reporter constructs, we demonstrate that BBR affects LDLR mRNA stability entirely through 3' untranslated region (UTR) in an ERK-dependent manner, and this stabilizing effect is more prominent in liver-derived cells than nonhepatic cell lines. In contrast to BBR, the mRNA stabilizing effect of bile acid chenodeoxycholic acid is mediated through the LDLR coding sequence, whereas the 5'UTR, 3'UTR, and the coding sequence of LDLR mRNA are all implicated in the action of phorbol 12-myristate 13-acetate. By performing UV cross-linking and SDS-PAGE, we identify 2 cytoplasmic proteins of 52 and 42 kDa that specifically bind to the LDLR 3'UTR in BBR-inducible and ERK-dependent manners. CONCLUSIONS: These new findings demonstrate that the BBR-induced stabilization of LDLR mRNA is mediated by the ERK signaling pathway through interactions of cis-regulatory sequences of 3'UTR and mRNA binding proteins that are downstream effectors of this signaling cascade.

3' Untranslated Regions↗

PubMed2005

Concentration and particle size of airborne toxic algae (brevetoxin) derived from ocean red tide events.

Red tides in the Gulf of Mexico are formed by blooms of the dinoflagellate Karenia brevis, which produces brevetoxins (PbTx). Brevetoxins can be transferred from water to air in the wind-powered whitecapped waves during red tide episodes. Inhalation exposure to marine aerosol containing PbTx causes respiratory problems. A liquid chromatograph/ tandem mass spectrometric method was developed for the detection and quantitation of several PbTxs in ambient samples collected during red tide events. This method was complemented by a previously developed antibody assay that analyzes the entire class of PbTx compounds. The method showed good linearity, accuracy, and reproducibility, allowing quantitation of PbTx compounds in the 10 pg/m3 range. Air concentrations of PbTxs and brevenal for individual samples ranged from 0.01 to 80 ng/m3. The particle size showed a single mode with a mass median diameter between 6 and 10 microm, which was consistent for all of the PbTx species that were measured. Our results imply that individual PbTxs were from the same marine aerosol or from marine aerosol that was produced from the same process. The particle size indicated the likelihood of high deposition efficiency in the respiratory tract with the majority of aerosol deposited in the upper airways and small but not insignificant deposition in the lower airways.

Aerosols↗