Cell fate decision is a critical step during physiological development when embryonic stem cells commit to either becoming adult stem cells or somatic cells. Recent advances in reprogramming demonstrate that a similar set of transcription factors (TFs), which are important for maintaining the pluripotent state of stem cells, can also reprogram somatic cells to induced pluripotent stem cells (iPSCs). In addition, trans-differentiation, which entails the use of different sets of defined factors, whereby one type of somatic cell can be directly converted into another and even to cell types from different germ layers has become a parallel widely used approach for switching cell fate. All these progresses have provided powerful tools to manipulate cells for basic science and therapeutic purposes. Besides protein-based factors, non-coding RNAs (ncRNAs), particularly microRNAs and long ncRNAs, are also involved in cell fate determination, including maintaining self-renewal of pluripotent stem cells and directing cell lineage. Targeting specific ncRNAs represents an alternative promising approach to optimize cell-based disease modeling and regenerative therapy. Here we focus on recent advances of ncRNAs in cell fate decision, including ncRNA-induced iPSCs and lineage conversion. We also discuss some underlying mechanisms and implications in molecular pathogenesis of human diseases.
ncRNAs; lncRNAs; microRNAs; reprogramming; trans-differentiation
No recent data exist on human papillomavirus (HPV) infection in Beijing, People's Republic of China.
Materials and method
We interviewed and examined a representative, randomly selected sample of 5552 sexually active women aged 25–54 years. Cervical cell samples were analysed for HPV DNA by a MY09/11-based PCR assay.
Human papillomavirus prevalence was 6.7% overall and 4.8% among women without cervical abnormalities. Of the 21 subtypes identified, HPV16 was the commonest type (2.6% overall; 39.1% of HPV-positive women), followed by HPV 58 (1.0%), 33 (0.8%), 43 (0.7%) and 56 (0.7%). High-risk HPV types predominated in all age groups. Human papillomavirus prevalence was highest in young to middle-aged women. Marital status, number of husband's sexual partners, age at sexual debut and nulligravidity were all associated with being HPV positive.
In our survey, HPV 16, HPV 58 and HPV 33 were the most prevalent HPV types in Beijing, indicating the potential for the prophylactic HPV 16/18 vaccine in China.
human papillomavirus; cervical neoplasia; China; epidemiology
Fas/APO-1 is a cell surface protein known to trigger apoptosis upon specific antibody engagement. Because wild-type p53 can activate transcription as well as induce apoptosis, we queried whether p53 might upregulate Fas/APO-1. To explore this possibility, we examined human p53-null (H358 non-small-cell lung adenocarcinoma and K562 erythroleukemia) and wild-type p53-containing (H460 non-small-cell lung adenocarcinoma) cell lines. When H358 or H460 cells were transduced with a replication-deficient adenovirus expression construct containing the human wild-type p53 gene but not with vector alone, a marked upregulation (approximately a three-to fourfold increase) of cell surface Fas/APO-1 was observed by flow cytometry. Similarly, K562, cells stably transfected with a plasmid vector containing the temperature-sensitive human p53 mutant Ala-143 demonstrated a four- to sixfold upregulation of Fas/APO-1 by flow-cytometric analysis at the permissive temperature of 32.5 degrees C. Temperature-sensitive upregulation of Fas/APO-1 in K562 Ala-143 cells was verified by immunoprecipitation and demonstrated to result from enhanced mRNA production by nuclear run-on and Northern (RNA) analyses. Stably transfected K562 cells expressing temperature-insensitive, transcriptionally inactive p53 mutants (His-175, Trp-248, His-273, or Gly-281) failed to upregulate Fas/APO-1 at either 32.5 degrees or 37.5 degrees C. The temperature-sensitive transcription of Fas/APO-1 occurred in the presence of cycloheximide, indicating that de novo protein synthesis was not required and suggested a direct involvement of p53. Collectively, these observations argue that Fas/APO-1 is a target gene for transcriptional activation by p53.
Recent data have linked hypoxia, a classic feature of the tumor microenvironment, to the function of specific microRNAs (miRNAs); however, whether hypoxia affects other types of noncoding transcripts is currently unknown. Starting from a genome-wide expression profiling, we demonstrate for the first time a functional link between oxygen deprivation and the modulation of long noncoding transcripts from ultraconserved regions, termed transcribed-ultraconserved regions (T-UCRs). Interestingly, several hypoxia-upregulated T-UCRs, henceforth named ‘hypoxia-induced noncoding ultraconserved transcripts' (HINCUTs), are also overexpressed in clinical samples from colon cancer patients. We show that these T-UCRs are predominantly nuclear and that the hypoxia-inducible factor (HIF) is at least partly responsible for the induction of several members of this group. One specific HINCUT, uc.475 (or HINCUT-1) is part of a retained intron of the host protein-coding gene, O-linked N-acetylglucosamine transferase, which is overexpressed in epithelial cancer types. Consistent with the hypothesis that T-UCRs have important function in tumor formation, HINCUT-1 supports cell proliferation specifically under hypoxic conditions and may be critical for optimal O-GlcNAcylation of proteins when oxygen tension is limiting. Our data gives a first glimpse of a novel functional hypoxic network comprising protein-coding transcripts and noncoding RNAs (ncRNAs) from the T-UCRs category.
ultraconserved genes; colorectal cancer; glioblastoma; hypoxia; OGT
Environmental factors are believed to play an important role in the pathogenesis of systemic sclerosis (SSc). Silica exposure has been implicated as potentially hazardous in epidemiological studies of SSc. It can activate fibroblasts to express profibrotic genes at certain conditions. The aim of this study is to examine whether the fibroblasts of SSc patients respond to silica particles with specific gene expressions differentially from normal control fibroblasts. The fibroblasts obtained from skin biopsies of 96 SSc patients and 104 controls were examined. Silica particles were used to perturb the cultures of the fibroblasts in time-course and dose-response assays. The transcript levels of COL1A2, COL3A1, MIVIP1, MMP3, TIMP3 and CTGF genes of the fibroblasts were measured with quantitative RT-PCR. The results showed that the expressions of all six genes in SSc fibroblasts under silica perturbation appeared significantly different from normal control fibroblasts. In age stratified analysis, compared to control fibroblasts, SSc fibroblasts from patients at age 30–40 years and 50–60 years displayed significantly decreased expressions of MMP1 gene in all dosage assays and increased expression of COL3A1 genes started at low dosages perturbation of silica particles, respectively. In autoantibody stratified analysis, specific gene expression patterns were significantly associated with autoantibody-subgroups of fibroblasts. A common feature of SSc fibroblasts was unstable and a wide range of gene expression changes in response to silica perturbation. Our studies may suggest an altered intrinsic dynamic control in SSc fibroblasts. In addition, sensitivity and specificity of SSc fibroblasts to potentially hazardous environmental trigger is age and autoantibody-subgroup-dependent. The fibroblasts of SSc patients at age 30–60 years may be more sensitive to silica perturbation toward a profibrotic gene expression.
scleroderma; fibroblasts; silica; gene expression; autoantibody
Fusion genes are hybrid genes that combine parts of two or more original genes. They can form as a result of chromosomal rearrangements or abnormal transcription, and have been shown to act as drivers of malignant transformation and progression in many human cancers. The biological significance of fusion genes together with their specificity to cancer cells has made them into excellent targets for molecular therapy. Fusion genes are also used as diagnostic and prognostic markers to confirm cancer diagnosis and monitor response to molecular therapies. High-throughput sequencing has enabled the systematic discovery of fusion genes in a wide variety of cancer types. In this review, we describe the history of fusion genes in cancer and the ways in which fusion genes form and affect cellular function. We also describe computational methodologies for detecting fusion genes from high-throughput sequencing experiments, and the most common sources of error that lead to false discovery of fusion genes.
Autophagy is a catabolic pathway utilized to maintain a balance among the synthesis, degradation, and recycling of cellular components, thereby playing a role in cell growth, development, and homeostasis. Previous studies revealed that a conditional knockout of essential member(s) of autophagy in a variety of tissues causes changes in structure and function of these tissues. Acinar cell-specific expression of knocked-in Cre recombinase through control of aquaporin 5 (Aqp5) promoter/enhancer (Aqp5-Cre) allows us to specifically inactivate Atg5, a protein necessary for autophagy, in salivary acinar cells of Atg5f/f;Aqp5-Cre mice. There was no difference in apoptotic or proliferation levels in salivary glands of Atg5/Cre mice from each genotype. However, H&E staining and electron microscopy studies revealed modestly enlarged acinar cells and accumulated secretory granules in salivary glands of Atg5f/f;Aqp5-Cre mice. Salivary flow rates and amylase contents of Atg5/Cre mice indicated that acinar-specific inactivation of ATG5 did not alter carbachol-evoked saliva and amylase secretion. Conversely, autophagy intersected with salivary morphological and secretory manifestations induced by isoproterenol administration. These results identified a role for autophagy as a homeostasis control in salivary glands. Collectively, Atg5f/f;Aqp5-Cre mice would be a useful tool to enhance our understanding of autophagy in adaptive responses following targeted head and neck radiation or Sjögren syndrome.
salivary gland; apoptosis; animal models; isoproterenol; proliferation
To  compare the frequency and severity of ultrasound (US) features in people with normal knees (controls), knee pain (KP), asymptomatic radiographic OA (ROA), and symptomatic OA (SROA),  examine relationships between US features, pain and radiographic severity,  explore the relationship between change in pain and US features over a 3-month period.
Community participants were recruited into a multiple group case–control study. All underwent assessment for pain, knee radiographs and US examination for effusion, synovial hypertrophy, popliteal cysts and power Doppler (PD) signal within the synovium. A 3-month follow-up was undertaken in over half of control and SROA participants.
243 participants were recruited (90 controls; 59 KP; 32 ROA; 62 SROA). Effusion and synovial hypertrophy were more common in ROA and SROA participants. Severity of effusion and synovial hypertrophy were greater in SROA compared to ROA (P < 0.05). Severity of US effusion and synovial hypertrophy were correlated with radiographic severity (r = 0.6 and r = 0.7, P < 0.01) but the relationship between pain severity and US features was weak (r = 0.3, P < 0.01). In SROA participants, pain severity did not change in tandem with a change in synovial hypertrophy over time.
US abnormalities are common in OA. Effusion and synovial hypertrophy were moderately correlated with radiographic severity but the relationship with pain is less strong. The degree to which these features reflect “active inflammation” is questionable and they may be better considered as part of the total organ pathology in OA. Further studies are warranted to confirm these findings.
Ultrasound; Knee osteoarthritis; Inflammation; Pain; Synovitis
Mechanical stimulation is known to regulate the calcification of endplate chondrocytes. The Ank protein has a strong influence on anti-calcification by transports intracellular inorganic pyrophosphate (PPi) to the extracellular matrix. It is known that TGF-β1 is able to induce Ank gene expression and protect chondrocyte calcification. Intermittent cyclic mechanical tension (ICMT) could induce calcification of endplate chondrocytes by decrease the expression of Ank gene. In this study, we investigated the relation of intermittent cyclic mechanical unconfined compression (ICMC) and Ank gene expression. We found that ICMC decreased the Ank gene expression in the endplate chondrocytes, and there was an decreased in the TGF-β1 expression after ICMC stimulation. The Ank gene expression significantly increased when treated by transforming growth factor alpha 1 (TGF-β1) in a dose-dependent manner and decreased when treated by SB431542 (ALK inhibitor) in a dose-dependent manner. Our results implicate that ICMC-induced downregulation of Ank gene expression may be regulated by TGF-β1 in end-plate chondrocytes.
Endplate chondrocytes; ICMC; Ank; TGF-β
Afatinib, an oral irreversible ErbB family blocker, showed comparable activity to cetuximab in patients with recurrent/metastatic head and neck squamous cell carcinoma in this phase II trial. Further, sequential EGFR/ErbB treatment provided sustained clinical benefit in some patients, suggesting a lack of cross-resistance.
Afatinib is an oral, irreversible ErbB family blocker that has shown activity in epidermal growth factor receptor (EGFR)-mutated lung cancer. We hypothesized that the agent would have greater antitumor activity compared with cetuximab in recurrent or metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) patients, whose disease has progressed after platinum-containing therapy.
Patients and methods
An open-label, randomized, phase II trial was conducted in 43 centers; 124 patients were randomized (1 : 1) to either afatinib (50 mg/day) or cetuximab (250 mg/m2/week) until disease progression or intolerable adverse events (AEs) (stage I), with optional crossover (stage II). The primary end point was tumor shrinkage before crossover assessed by investigator (IR) and independent central review (ICR).
A total of 121 patients were treated (61 afatinib, 60 cetuximab) and 68 crossed over to stage II (32 and 36 respectively). In stage I, mean tumor shrinkage by IR/ICR was 10.4%/16.6% with afatinib and 5.4%/10.1% with cetuximab (P = 0.46/0.30). Objective response rate was 16.1%/8.1% with afatinib and 6.5%/9.7% with cetuximab (IR/ICR). Comparable disease control rates were observed with afatinib (50%) and cetuximab (56.5%) by IR; similar results were seen by ICR. Most common grade ≥3 drug-related AEs (DRAEs) were rash/acne (18% versus 8.3%), diarrhea (14.8% versus 0%), and stomatitis/mucositis (11.5% versus 0%) with afatinib and cetuximab, respectively. Patients with DRAEs leading to treatment discontinuation were 23% with afatinib and 5% with cetuximab. In stage II, disease control rate (IR/ICR) was 38.9%/33.3% with afatinib and 18.8%/18.8% with cetuximab.
Afatinib showed antitumor activity comparable to cetuximab in R/M HNSCC in this exploratory phase II trial, although more patients on afatinib discontinued treatment due to AEs. Sequential EGFR/ErbB treatment with afatinib and cetuximab provided sustained clinical benefit in patients after crossover, suggesting a lack of cross-resistance.
afatinib; cetuximab; recurrent HNSCC; metastatic HNSCC; EGFR inhibitor therapy
Malignant gliomas have low survival expectations regardless of current treatments. Nonsteroidal anti-inflammatory drugs (NSAIDs) prevent cell transformation and slow cancer cell growth by mechanisms independent of cyclooxygenase (COX) inhibition. Certain NSAIDs trigger the endoplasmic reticulum stress response (ERSR), as revealed by upregulation of molecular chaperones such as GRP78 and C/EBP homologous protein (CHOP). Although celecoxib (CELE) inhibits the sarcoendoplasmic reticulum Ca2+ ATPase (SERCA), an effect known to induce ERSR, sulindac sulfide (SS) has not been reported to affect SERCA. Here, we investigated these two drugs for their effects on Ca2+ homeostasis, ERSR, and glioma cell survival. Our findings indicate that SS is a reversible inhibitor of SERCA and that both SS and CELE bind SERCA at its cyclopiazonic acid binding site. Furthermore, CELE releases additional Ca2+ from the mitochondria. In glioma cells, both NSAIDS upregulate GRP78 and activate ER-associated caspase-4 and caspase-3. Although only CELE upregulates the expression of CHOP, it appears that CHOP induction could be associated with mitochondrial poisoning. In addition, CHOP induction appears to be uncorrelated with the gliotoxicity of these NSAIDS in our experiments. Our data suggest that activation of ERSR is primarily responsible for the gliotoxic effect of these NSAIDS. Because SS has good brain bioavailability, has lower COX-2 inhibition, and has no mitochondrial effects, it represents a more appealing molecular candidate than CELE to achieve gliotoxicity via activation of ERSR.
GRP78; gliotoxicity; Ca2+; NSAIDs
Disturbing mitotic progression via targeted anti-mitotic therapy is an attractive strategy for cancer treatment. Therefore, the exploration and elucidation of molecular targets and pathways in mitosis are critical for the development of anti-mitotic drugs. Here, we show that cell division cycle 5-like (Cdc5L), a pre-mRNA splicing factor, is a regulator of mitotic progression. Depletion of Cdc5L causes dramatic mitotic arrest, chromosome misalignments and sustained activation of spindle assembly checkpoint, eventually leading to mitotic catastrophe. Moreover, these defects result from severe impairment of kinetochore-microtubule attachment and serious DNA damage. Genome-wide gene expression analysis reveals that Cdc5L modulates the expression of a set of genes involved in the mitosis and the DNA damage response. We further found that the pre-mRNA splicing efficiency of these genes were impaired when Cdc5L was knocked down. Interestingly, Cdc5L is highly expressed in cervical tumors and osteosarcoma. Finally, we demonstrate that downregulation of Cdc5L decreases the cell viability of related tumor cells. These results suggest that Cdc5L is a key regulator of mitotic progression and highlight the potential of Cdc5L as a target for cancer therapy.
mitotic catastrophe; chromosome misalignment; RNA processing
Aging refers to the physical and functional decline of the tissues over time that often leads to age-related degenerative diseases. Accumulating evidence implicates that the senescence of neural stem cells (NSCs) is of paramount importance to the aging of central neural system (CNS). However, exploration of the underlying molecular mechanisms has been hindered by the lack of proper aging models to allow the mechanistic examination within a reasonable time window. In the present study, we have utilized a hydroxyurea (HU) treatment protocol and effectively induced postnatal subventricle NSCs to undergo cellular senescence as determined by augmented senescence-associated-β-galactosidase (SA-β-gal) staining, decreased proliferation and differentiation capacity, increased G0/G1 cell cycle arrest, elevated reactive oxygen species (ROS) level and diminished apoptosis. These phenotypic changes were accompanied by a significant increase in p16, p21 and p53 expression, as well as a decreased expression of key proteins in various DNA repair pathways such as xrcc2, xrcc3 and ku70. Further proteomic analysis suggests that multiple pathways are involved in the HU-induced NSC senescence, including genes related to DNA damage and repair, mitochondrial dysfunction and the increase of ROS level. Intriguingly, compensatory mechanisms may have also been initiated to interfere with apoptotic signaling pathways and to minimize the cell death by downregulating Bcl2-associated X protein (BAX) expression. Taken together, we have successfully established a cellular model that will be of broad utilities to the molecular exploration of NSC senescence and aging.
aging; neural stem cells; cellular senescence model; stress; DNA damage
Our objective was to examine associations of adult weight gain and nonalcoholic
fatty liver disease (NAFLD). Cross-sectional interview data from 844 residents
in Wan Song Community from October 2009 to April 2010 were analyzed in
multivariate logistic regression models to examine odds ratios (OR) and 95%
confidence intervals (CI) between NAFLD and weight change from age 20.
Questionnaires, physical examinations, laboratory examinations, and
ultrasonographic examination of the liver were carried out. Maximum rate of
weight gain, body mass index, waist circumference, waist-to-hip ratio, systolic
blood pressure, diastolic blood pressure, fasting blood glucose, cholesterol,
triglycerides, uric acid, and alanine transaminase were higher in the NAFLD
group than in the control group. HDL-C in the NAFLD group was lower than in the
control group. As weight gain increased (measured as the difference between
current weight and weight at age 20 years), the OR of NAFLD increased in
multivariate models. NAFLD OR rose with increasing weight gain as follows: OR
(95%CI) for NAFLD associated with weight gain of 20+ kg compared to stable
weight (change <5 kg) was 4.23 (2.49-7.09). Significantly increased NAFLD OR
were observed even for weight gains of 5-9.9 kg. For the “age 20 to highest
lifetime weight” metric, the OR of NAFLD also increased as weight gain
increased. For the “age 20 to highest lifetime weight” metric and the “age 20 to
current weight” metric, insulin resistance index (HOMA-IR) increased as weight
gain increased (P<0.001). In a stepwise multivariate regression analysis,
significant association was observed between adult weight gain and NAFLD
(OR=1.027, 95%CI=1.002-1.055, P=0.025). We conclude that adult weight gain is
strongly associated with NAFLD.
China; Diabetes; Insulin resistance; Lipidosis; Nonalcoholic fatty liver disease; Obesity
Early serum detection is of critical importance to improve the therapy for hepatocellular carcinoma (HCC), one of the most deadly cancers. Hepatitis infection is a leading cause of HCC.
In the present study, we collected total serum samples with informed consent from 80 HCC patients with HBV (+)/cirrhosis (+), 80 patients with benign diseases (50 liver cirrhosis patients and 30 HBV-infected patients) and 60 healthy controls. Analysis was by using surface-enhanced laser desorption/ionisation-time-of-flight mass spectroscopy (SELDI-TOF-MS) to find new serum markers of HCC. SELDI peaks were isolated by SDS–PAGE, identified by LC-MS/MS and validated by immunohistochemistry (IHC) in liver tissues. Migration and invasion assay were performed to test the ability of cell migration and invasion in vitro.
SELDI-TOF-MS revealed a band at 7777 M/Z in the serum samples from HCC patients but not from healthy controls or patients with benign diseases. The protein (7777.27 M/Z) in the proteomic signature was identified as C-C motif chemokine 15 (CCL15) by peptide mass fingerprinting. A significant increase in serum CCL15 was detected in HCC patients. Functional analysis showed that HCC cell expressed CCL15, which in turn promoted HCC cell migration and invasion.
CCL15 may be a specific proteomic biomarker of HCC, which has an important role in tumorigenesis and tumour invasion.
CCL15; biomarker; HCC; migration; invasion
Dietary glycemic index (GI) and glycemic load (GL) typically have a positive relationship with obesity and diabetes, which are risk factors for liver cancer. However, studies on their association with liver cancer have yielded inconsistent results. Therefore, we assessed the association of GI, GL, and carbohydrates with liver cancer risk.
Patients and methods
A total of 72 966 women and 60 207 men from the Shanghai Women's Health Study (SWHS) and the Shanghai Men's Health Study (SMHS) were included for analysis. Food frequency questionnaire (FFQ) data were used to calculate daily dietary GI, GL, and carbohydrate intake. These values were energy adjusted and categorized into quintiles. The hazard ratios (HRs) and 95% confidence intervals (CI) were calculated with adjustment for potential confounders.
After a median follow-up time of 11.2 years for the SWHS and 5.3 years for the SMHS, 139 and 208 incident liver cancer cases were identified in the SWHS and SMHS, respectively. In multivariable Cox regression models, no statistically significant trends by quintile of GI, GL, or carbohydrate intake were observed. Stratification by chronic liver disease/hepatitis, diabetes, or body mass index (BMI) did not alter the findings.
There is little evidence that dietary GI, GL, or carbohydrates affect the incidence of liver cancer in this Asian population.
Chinese men and women; cohort study; diet; glycemic index; glycemic load; primary liver cancer
A number of epidemiological studies have reported inconsistent findings on the association between meat consumption and lung cancer.
We therefore conducted a systematic review and meta-analysis to investigate the relationship between meat consumption and lung cancer risk in epidemiological studies.
Twenty-three case–control and 11 cohort studies were included. All studies adjusted for smoking or conducted in never smokers. The summary relative risks (RRs) of lung cancer for the highest versus lowest intake categories were 1.35 (95% confidence interval (CI) 1.08–1.69) for total meat, 1.34 (95% CI 1.18–1.52) for red meat, and 1.06 (95% CI 0.90–1.25) for processed meat. An inverse association was found between poultry intake and lung cancer (RR = 0.91, 95% CI 0.85–0.97), but not for total white meat (RR = 1.06, 95% CI 0.82–1.37) or fish (RR = 1.01, 95% CI 0.96–1.07).
The relationship between meat intake and lung cancer risk appears to depend on the types of meat consumed. A high intake of red meat may increase the risk of lung cancer by about 35%, while a high intake of poultry decreases the risk by about 10%. More well-designed cohort studies on meat mutagens or heme iron, meat cooking preferences, and doneness level are needed to fully characterize this meat–lung cancer association.
case–control study; cohort study; lung cancer; meat consumption; meta-analysis
The receptor for advanced glycation end-products (RAGE) is an oncogenic trans-membranous receptor, which is overexpressed in multiple human cancers. However, the role of RAGE in gastric cancer is still elusive. In this study, we investigated the expression and molecular mechanisms of RAGE in gastric cancer cells. Forty cases of gastric cancer and corresponding adjacent non-cancerous tissues (ANCT) were collected, and the expression of RAGE was assessed using immunohistochemistry (IHC) in biopsy samples. Furthermore, RAGE signaling was blocked by constructed recombinant small hairpin RNA lentiviral vector (Lv-shRAGE) used to transfect into human gastric cancer SGC-7901 cells. The expression of AKT, proliferating cell nuclear antigen (PCNA) and matrix metallopeptidase-2 (MMP-2) was detected by Real-time PCR and Western blot assays. Cell proliferative activities and invasive capability were respectively determined by MTT and Transwell assays. Cell apoptosis and cycle distribution were analyzed by flow cytometry. As a consequence, RAGE was found highly expressed in cancer tissues compared with the ANCT (70.0% vs 45.0%, P=0.039), and correlated with lymph node metastases (P=0.026). Knockdown of RAGE reduced cell proliferation and invasion of gastric cancer with decreased expression of AKT, PCNA and MMP-2, and induced cell apoptosis and cycle arrest. Altogether, upregulation of RAGE expression is associated with lymph node metastases of gastric cancer, and blockade of RAGE signaling suppresses growth and invasion of gastric cancer cells through AKT pathway, suggesting that RAGE may represent a potential therapeutic target for this aggressive malignancy.
RAGE; gastric cancer; growth; invasion
MiR-133 was found to be specifically expressed in cardiac and skeletal muscle in previous studies. There are two members in the miR-133 family: miR-133a and miR-133b. Although previous studies indicated that miR-133a was related to myogenesis, the signaling pathways regulated by miR-133 were still not very clear. In this study, we showed that both miR-133a and miR-133b were upregulated during myogenesis through Solexa sequencing. We confirmed that miR-133 could promote myoblast differentiation and inhibit cell proliferation through the regulation of the extracellular signal-regulated kinase (ERK) signaling pathway in C2C12 cells. FGFR1 and PP2AC, which both participate in signal transduction of the ERK1/2 pathway, were found to be negatively regulated by miR-133a and miR-133b at the post-transcriptional level. Also, downregulation of ERK1/2 phosphorylation by miR-133 was detected. FGFR1 and PP2AC were also found to repress C2C12 differentiation by specific siRNAs. In addition, we found that inhibition of ERK1/2 pathway activity can inhibit C2C12 cell proliferation and promote the initiation of differentiation but form short and small myotubes. Furthermore, we found that the expression of miR-133 was negatively regulated by ERK1/2 signaling pathway. In summary, we demonstrated the role of miR-133 in myoblast and further revealed a new feedback loop between miR-133 and the ERK1/2 signaling pathway involving an exquisite mechanism for regulating myogenesis.
miR-133; ERK1/2; FGFR1; PP2AC; myoblast; differentiation
The current-induced motion of magnetic domain walls (DWs) confined to nanostructures is of great interest for fundamental studies as well as for technological applications in spintronic devices. Here, we present magnetic images showing the depinning properties of pulse-current-driven domain walls in well-shaped Permalloy nanowires obtained using photoemission electron microscopy combined with x-ray magnetic circular dichroism. In the vicinity of the threshold current density (Jth = 4.2 × 1011 A.m−2) for the DW motion, discontinuous DW depinning and motion have been observed as a sequence of “Barkhausen jumps”. A one-dimensional analytical model with a piecewise parabolic pinning potential has been introduced to reproduce the DW hopping between two nearest neighbour sites, which reveals the dynamical nature of the current-driven DW motion in the depinning regime.
Interferon regulatory factor 5(IRF5) located on human chromosome 7q32 is associated with many chronic inflammatory disorders. IRF5 is the key regulator of proinflammatory cytokines and type I interferons. We surveyed two cohorts of inflammatory bowel disease (IBD) patients from a North American Consortium. Six single-nucleotide polymorphisms and a 5-base-pair (bp) insertion-deletion (CGGGG indel)polymorphism were investigated. Cytokine secretion was measured in primary lymphocytes after toll-like receptor 9 stimulation. Two-marker haplotypes containing the pairs (rs4728142-CGGGG indel) and (CGGGG indel-rs7808907) were associated with IBD protection (P = 2.89 × 10−6, P = 9.32 × 10−4 (non-Jewish ancestry) and P = 4.68 × 10−8, P = 2.50 × 10−8 (Jewish ancestry)) and IBD risk (P = 0.004, P = 0.003 (Jewish ancestry), respectively. IRF5 polymorphisms were risk factors for IBD in a single cohort. Interleukin-12-p70 cytokine production was higher (P = 0.04) in lymphocytes from controls with two alleles of the 5-bp insertion. IRF5 polymorphisms contribute to the risk profile for Crohn’s disease and ulcerative colitis along with ancestry and NOD2 genotypes.
inflammatory bowel disease; Crohn’s disease; ulcerative colitis; interferon regulatory factor 5; polymorphisms; haplotype
Cancer stem cells (CSCs) are believed to be a promising target for cancer therapy because these cells are responsible for tumor development, maintenance and chemotherapy resistance. Finding out the critical factors regulating CSC fate is the key for target therapy of CSCs. Just as normal stem cells are regulated by their microenvironment (niche), CSCs are also regulated by cells in the tumor microenvironment. However, whether various tumor microenvironments can induce CSCs to differentiate into different cancer cells is not clear. Here, we show that single-cell-cloned CSCs, accidentally obtained from a human liver cancer microvascular endothelial cells, express classic stem cell markers, genes associated with self-renewal and pluripotent factors and possess colony-forming ability in vitro and the ability of serial transplantation in vivo. The single-cell-cloned CSCs treated with the different tumor cell/tissue-derived conditioned culture medium, which is a mimic of carcinoma microenvironment, could differentiate into corresponding tumor cells and express specific markers of the respective type of tumor cells at the gene, protein and cell levels, respectively. Interestingly, this multilineage differentiation potential of single-cell-cloned liver CSCs sharply declined after the specific knockdown of octamer-binding transcription factor 4 (Oct4) alone, even though they were under the same induction conditions (carcinoma microenvironments). These data support the hypothesis that single-cell-cloned liver CSCs have the potential of differentiating into different types of tumor cells, and the tumor microenvironment does play a crucial role in deciding differentiation directions. Simultaneously, Oct4 in CSCs is indispensable in this process. These factors are promising targets for liver CSC-specific therapy.
CSCs; carcinoma/cancer microenvironments; multilineage differentiation potential; Oct4; microvascular endothelial cells
The aim of this study was to evaluate the effect of monochrome liquid crystal displays (LCDs) with different resolutions on observer performance during detection of small solitary pulmonary nodules.
Chest images of digital radiography were selected online from the hospital's picture archiving and communication system. Of the 164 images selected, small solitary non-calcified pulmonary nodules were present in 63 images and absent in 101 images. Observer performance was assessed among 3 extremely experienced, 3 very experienced and 3 moderately experienced radiologists, who independently interpreted these images on 2, 3 and 5 megapixel greyscale LCDs. A five-point confidence level rating scale was used to represent the presence of nodules: definite absence, probable absence, indetermination, probable presence and definite presence. The observers were requested to rank each image on the given display according to the presence of the pulmonary nodule. Observer performance was analysed in terms of receiver operating characteristics (ROCs).
The areas under the ROC curves which represented the observer performance for the 2, 3 and 5 megapixel LCDs were found to be 0.705, 0.722 and 0.764, respectively, for the extremely experienced radiologists; 0.687, 0.712 and 0.721, respectively, for the very experienced radiologists; and 0.689, 0.696 and 0.711, respectively, for the moderately experienced radiologists. These differences were not statistically significant.
The observer performances for detection of small solitary non-calcified pulmonary nodules by radiologists with varying degrees of experience were comparable between the 2, 3 and 5 megapixel monochrome LCDs.