Large intergenic non-coding RNAs (lincRNA) regulate development and disease via interactions with their protein partners. Expression of the lincRNA HOX transcript antisense RNA (HOTAIR) is elevated in a variety of malignancies and linked to metastasis and poor prognosis. HOTAIR promotes proliferation, invasion, and metastasis in the preclinical studies of cancer through modulation of chromatin modifying complexes. In the current review we discuss the molecular mechanisms of HOTAIR-mediated aggressive phenotypes of cancer, HOTAIR’s potential in cancer intervention, and challenges in exploration of HOTAIR in cancer biology.
lincRNA; cancer; PRC2; EZH2; metastasis
Osteosarcoma (OS) has an unfavorable prognosis and tends to metastasize to lung tissue. Although the CXCL12-CXCR4 axis appears to affect progression and metastasis in numerous tumors, its mechanism and downstream pathways in OS remain unclear. We used western blotting and flow cytometry to detect CXCR4 and CXCR7 expression in two OS cell lines (LM8 and Dunn). An MTT assay was used to evaluate the effects of CXCL12 and AMD3100, a specific CXCR4 antagonist, on cell viability. Flow cytometry was utilized to analyze changes in apoptosis induced by serum deprivation following treatment with CXCL12 and AMD3100. A Transwell assay was used to assess cell migration in response to CXCL12 and AMD3100. Western blotting was performed to identify the phosphorylation of signaling molecules (JNK, c-Jun, Akt, p38 and Erk1/2) and expression of caspase-3 and -8, and PARP. Mouse models were employed to evaluate AMD3100 inhibition of primary OS growth and lung metastasis in vivo. CXCR4 expression was detected in LM8 but not Dunn cells, and neither cell line expressed CXCR7. The addition of CXCL12 induced the survival and migration of serum-starved CXCR4+ LM8 cells activating JNK and Akt pathways, which were abrogated by adding AMD3100. However, similar results were not observed in CXCR4− Dunn cells. CXCL12 protected LM8, but not Dunn cells, from apoptosis induced by serum deprivation by suppressing PARP cleavage, which was partly reversed by AMD3100. In a mouse model, AMD3100 reduced primary tumor growth and lung metastasis compared with the controls. Thus, the CXCL12-CXCR4 axis regulated OS survival and metastasis through the JNK and Akt pathways, and blocking them with AMD3100 was found to be a potential OS treatment.
osteosarcoma; chemokine 12; chemokine receptor 4; AMD3100; survival; metastasis
Long non-coding RNAs (lncRNAs) govern fundamental biochemical and cellular processes. lncRNA HOX transcript antisense RNA (HOTAIR) represses gene expression through recruitment of chromatin modifiers. The expression of HOTAIR is elevated in lung cancer and correlates with metastasis and poor prognosis. Moreover, HOTAIR promotes proliferation, survival, invasion, metastasis, and drug resistance in lung cancer cells. Here we review the molecular mechanisms underlying HOTAIR-mediated aggressive phenotypes of lung cancer. We also discuss HOTAIR’s potential in diagnosis and treatment of lung cancer, as well as the challenges of exploiting HOTAIR for intervention of lung cancer.
lncRNA; HOTAIR; Lung cancer; PRC2; Metastasis
Papillary thyroid cancer (PTC) often presents as multifocal. However, the association of multifocality with poor prognosis remains controversial. The aim of this retrospective study was to identify the characteristics of PTC with multiple foci and to evaluate the association between multifocality and prognosis.
We reviewed the medical records of 496 patients who underwent total thyroidectomy for PTC. Patients were classified as G1 (1 tumor focus), G2 (2 foci), and G3 (3 or more foci). We analyzed the clinicopathological features and clinical outcomes in each classification. A Cox regression model was used to assess the relationship between multifocality and recurrence or cancer mortality.
The G1, G2 and G3 groups included 287, 141 and 68 patients, respectively. The mean age was 47.1 ± 16.1 yr in G1, 41.1 ± 18.4 yr in G2, and 35.5 ± 15.9 yr in G3 and differed significantly among the 3 groups (p = 0.001). The proportion of extrathyroidal extension, central lymph node metastasis (CLNM), and lateral lymph node metastasis (LLNM) in the G1 to G3 groups increased with increasing number of tumor foci. The Kaplan–Meier curves revealed that G3 had the shortest recurrence-free survival, and differences were significant among the 3 groups (p = 0.001, Log Rank test). Furthermore, cancer-specific survival rates decreased significantly with increasing number of tumor foci (p = 0.041). Independent predictors of recurrence by multivariate Cox analysis included >3 tumor foci [HR 2.60, 95% confidence interval (CI) 1.53-4.39, p = 0.001] and extrathyroidal extension (HR 1.95, CI 1.12-3.38, p = 0.018).
An increase in the number of tumors is associated with a tendency toward more aggressive features and predicts poor prognosis in PTC.
Papillary thyroid carcinoma; Multifocality; Recurrence; Mortality
(1) Background: The genetic predisposition to papillary thyroid cancer (PTC) is far from clearly elucidated. Rs2292832 is a genetic polymorphism that located in the precursor of mir-149 and has been studied in diverse cancers. Thus far, the role of rs2292832 in PTC tumorigenesis and progression was unclear; (2) Method: Rs2292832 was genotyped in 838 PTCs, 495 patients with thyroid benign tumors (BNs) and 1006 controls in a Chinese Han population. Clinicopathological data was collected and compared. The expression level of mature mir-149 was examined in 55 normal thyroid tissue samples; (3) Results: The CC genotype of rs2292832 was significantly associated with an increased risk of PTC compared with TT homozygote (OR = 1.60, 95% CI: 1.72–2.20, p = 0.003) and TT/TC combined genotype (OR = 1.54, 95% CI: 1.14–2.09, p = 0.005). Rs2292832 is an independent risk factor correlated with tumor invasion (p = 0.006) and higher T stage in PTC patients (p = 0.007), but uncorrelated with short-term disease persistence of PTC. PTC subjects carrying CC genotype have lower mir-149-5p expression than those with TC genotype (p = 0.002). Twelve predicted target genes have been identified by collaboratively using computational tools; (4) Conclusion: Rs2292832 was possibly involved in the susceptibility and local progression of PTC in Chinese patients, by altering the expression level of mir-149-5p and its target genes.
rs2292832; has-mir-149; PTC susceptibility; clinicopathological characteristics
Accurate prediction of a particular cancer can be achieved by measuring multiplex biomarkers. Traditional methods for multi-biomarkers detection are either multi-spots assay with chip or multi-label assay with one detection spot. However, the detection throughput of these two approaches is limited by the substrate area and the numbers of available label respectively. To solve this problem, in the present study, an immunoassay was firstly prepared by combining multi-label strategy and multi-spot assay with a novel array electrode for simultaneous detection of six biomarkers for hepatocellular carcinoma (HCC). The detection throughput of the proposed method was doubled in comparison with traditional multi-spots assay (one target protein was detected on each analytic spot), which could greatly enhance the sensitivity and specificity of HCC diagnosis. This detection model may serve as the starting point for high throughput of multianalyte assay.
Three-dimensional organotypic culture using reconstituted basement membrane matrix (rBM 3-D) is an invaluable tool to characterize morphogenesis of epithelial cells and to elucidate the tumor-modulating actions of extracellular matrix. microRNAs (miRNA) are a novel class of tumor modulating genes. A substantial amount of investigation of miRNAs in cancer is carried out using monolayer 2-D culture on plastic substratum, which lacks a consideration of the matrix-mediated regulation of miRNAs. In the current study we compared the expression of miRNAs in rBM 3-D and 2-D cultures of two lung adenocarcinoma cell lines. Our findings revealed a profound difference in miRNA profiles between 2-D and rBM 3-D cultures of lung adenocarcinoma cells. The rBM 3-D culture-specific miRNA profile was highlighted with higher expression of the tumor suppressive miRNAs (i.e., miR-200 family) and lower expression of the oncogenic miRNAs (i.e., miR-17~92 cluster and miR-21) than that of 2-D culture. Moreover, the expression pattern of miR-17, miR-21, and miR-200a in rBM 3-D culture correlated with the expression of their targets and acinar morphogenesis, a differentiation behavior of lung epithelial cells in rBM 3-D culture. Over-expression of miR-21 suppressed its target PTEN and disrupted acinar morphogenesis. In summary, we provide the first miRNA profile of lung adenocarcinoma cells in rBM 3-D culture with respect to acinar morphogenesis. These results indicate that rBM 3-D culture is essential to a comprehensive understanding of the miRNA biology in lung epithelial cells pertinent to lung adenocarcinoma.
microRNA; three-dimensional organotypic culture; extracellular matrix; lung epithelial cells; morphogenesis
Lymph node metastasis has a significant impact on laryngeal cancer prognosis. The role of lymph node ratio (LNR, ratio of metastatic to examined nodes) in the staging of laryngeal cancer was not reported.
Patients and Methods
Records of laryngeal cancer patients with lymph node involvement from Surveillance, Epidemiology, and End Results database (SEER, training set, N = 1963) and Fudan University Shanghai Cancer Center (FDSCC, validating set, N = 27) were analyzed for the prognostic value of LNR. Kaplan–Meier survival estimates, the Log-rank χ2 test and Cox proportional hazards model were used for univariate and multivariate analysis. Optimal LNR cutoff points were identified by X-tile.
Optimal LNR cutoff points classified patients into three risk groups R1 (≤0.09), R2 (0.09–0.20) and R3 (>0.20), corresponding to 5-year cause-specific survival and overall survival in SEER patients of 55.1%, 40.2%, 28.8% and 43.1%, 31.5%, 21.8%, 2-year disease free survival and disease specific survival in FDSCC patients of 74.1%, 62.5%, 50.0%, and 67.7%, 43.2%, 25.0%, respectively. R3 stratified more high risk patients than N3 with the same survival rate, and R classification clearly separated N2 patients to 3 risk groups and N1 patients to 2 risk groups (R1–2 and R3).
R classification is a significant prognostic factor of laryngeal cancer and should be used as a complementary staging system of N classification.
The exponential growth of gigantic biological data from various sources, such as protein-protein interaction (PPI), genome sequences scaffolding, Mass spectrometry (MS) molecular networking and metabolic flux, demands an efficient way for better visualization and interpretation beyond the conventional, two-dimensional visualization tools.
We developed a 3D Cytoscape Client/Server (3DScapeCS) plugin, which adopted Cytoscape in interpreting different types of data, and UbiGraph for three-dimensional visualization. The extra dimension is useful in accommodating, visualizing, and distinguishing large-scale networks with multiple crossed connections in five case studies.
Evaluation on several experimental data using 3DScapeCS and its special features, including multilevel graph layout, time-course data animation, and parallel visualization has proven its usefulness in visualizing complex data and help to make insightful conclusions.
The tumor microenvironment is a crucial determinant in tumor progression. Interstitial extracellular matrix (ECM), such as type I collagen (Col-1), is aberrantly enriched in the tumor microenvironment and promotes tumor progression. Long intergenic non-coding RNAs (lincRNA) are a new family of regulatory RNAs that modulate fundamental cellular processes via diverse mechanisms.
We investigated whether the expression of lincRNAs was regulated by the tumor promoting Col-1. In a three-dimensional organotypic culture model using the reconstituted basement membrane ECM Matrigel (rBM 3-D), supplementation of Col-1 disrupted acini, a differentiation feature of well-differentiated lung adenocarcinoma cells, and concurrently induced the expression of a tumor-promoting lincRNA, HOX transcript antisense RNA (HOTAIR). Induction of HOTAIR by Col-1 was diminished by a neutralizing antibody against the Col-1 receptor α2β1 integrin. Col-1 activates the expression of a reporter gene controlled by the human HOTAIR promoter. Moreover the expression of HOTAIR and Col-1 was concurrently up-regulated in human non-small cell lung cancer.
Our findings indicate that tumor-promoting Col-1 up-regulates the expression of HOTAIR in NSCLC cells. These initial results warrant further investigation of HOTAIR and other lincRNA genes in lung tumorigenesis.
HOTAIR; lincRNA; Type I collagen; Three-dimensional ogranotypic culture
With the emergence of next-generation sequencing, the availability of prokaryotic genome sequences is expanding rapidly. A total of 5,276 genomes have been released since 2008, yet only 1,692 genomes were complete. The final phase of microbial genome sequencing, particularly gap closing, is frequently the rate-limiting step either because of complex genomic structures that cause sequence bias even with high genomic coverage, or the presence of repeat sequences that may cause gaps in assembly.
We have developed a Cytoscape plugin to facilitate gap closing for high-throughput sequencing data from microbial genomes. This plugin is capable of interactively displaying the relationships among genomic contigs derived from various sequencing formats. The sequence contigs of plasmids and special repeats (IS elements, ribosomal RNAs, terminal repeats, etc.) can be displayed as well.
Displaying relationships between contigs using graphs in Cytoscape rather than tables provides a more straightforward visual representation. This will facilitate a faster and more precise determination of the linkages among contigs and greatly improve the efficiency of gap closing.
ContigScape; Repeat contig; Microbial; Visualization; Linkage; Gap closing
The genome of Amycolatopsis mediterranei S699 was resequenced and assembled de novo. By comparing the sequences of S699 previously released and that of A. mediterranei U32, about 10 kb of major indels was found to differ between the two S699 genomes, and the differences are likely attributable to their different assembly strategies.
There is growing interest in discovery of novel bioactive natural products from Burkholderia thailandensis. Here we report a significantly improved genome sequence and reannotation of Burkholderia thailandensis MSMB43, which will facilitate the discovery of new natural products through genome mining and studies of the metabolic versatility of this bacterium.
Rs2910164, a Single nucleotide polymorphism (SNP) located in the precursor microRNA sequence of miR-146a, is the only MicroRNA sequence SNP studied in papillary thyroid cancer (PTC). Association studies had been performed in US and UK-Northern European populations, but results were inconsistence. This study evaluated the association between rs2910164 and the risk of PTC as well as benign thyroid tumor (BN), and examined the clinicopathological characteristics of PTC and BN for different genotypes.
This case-control study genotyped rs2910164 in 753 PTCs, 484 BNs and 760 controls in a Chinese Han population. Clinicopathological and genetic data were collected and compared. Multivariate logistic regression was performed to calculate adjusted odds ratios (ORs).
There were no differences in rs2910164 genotype distributions between the three groups. PTC cases with three genotypes (CC, CG, GG) had similar clinicopathological characteristics except the existence of “para-cancer” BN (PTC/BN, P = 0.006). PTC/BN patients were older (P = 0.009), and had smaller cancer lesions (P<0.001), lower serum thyrotropin levels (1.82±1.42 vs. 2.21±1.74, P = 0.04), and lower rates of level VI lymph node metastasis (20.8% vs. 52.7%, P<0.001) and lateral neck lymph node metastasis (11.5% vs. 23.0%, P = 0.011) compared with PTC only. Then we supposed a possible progression from BN to PTC which may involve rs2910164 in and performed a multivariate logistic regression analysis of PTC/BN and BN cases to determine risk factors of this progression. Results showed that the rs2910164 GG homozygote (OR = 2.25, 95% CI 1.22–4.14, P = 0.01) was the only risk factor in this study.
Rs2910164 was not associated with increased risk of PTC and BN in Chinese patients, but may play a latent role in the transformation from BN to PTC.
A fribotic tumor microenvironment promotes progression of cancer. In this study, we utilize a reconstituted basement membrane mimics Matrigel based three-dimensional organotypic culture (rBM 3-D) to investigate the mechanisms that mediate the tumor promoting effects of the fibrogenic mediators TGF-β1 and type I collagen (Col-1) on lung adenocarcinoma cells. Similar to normal alveolar epithelial cells, the well-differentiated lung adenocarcinoma cells in rBM 3-D culture undergo acinar morphogeneis that features polarized epithelial cell spheres with a single central lumen. Either TGF-β1 or Col-1 modestly distorts acinar morphogenesis. On the other hand, TGF-β1 and Col-1 synergistically induce a transition from acinar morphology into stellate morphology that is characteristic of invasive and metastatic cancer cells. Inhibition of the Src kinase activity abrogates induction of stellate morphology, activation of Akt and mTOR, and the expression of tumor promoting genes by TGF-β1 and Col-1. To a similar extent, pharmacological inhibition of mTOR abrogates the cellular responses to TGF-β1 and Col-1. In summary, we demonstrate that TGF-β1 and Col-1 promote stellate morphogenesis of lung cancer cells. Our findings further suggest that the Src-Akt-mTOR axis mediates stellate morphogenesis. These findings also indicate that rBM 3-D culture can serve as an ideal platform for swift and cost-effective screening of therapeutic candidates at the interface of the tumor and its microenvironment.
TGF-β1; Src; Type I collagen; Three-dimensional culture; Extracellular matrix
The goal of this study was to identify the clinicopathological factors of co-existing papillary thyroid cancer (PTC) in patients with Hashimoto’s thyroiditis (HT) and provide information to aid in the diagnosis of such patients.
This study included 6109 patients treated in a university-based tertiary care cancer hospital over a 3-year period. All of the patients were categorised based on their final diagnosis. Several clinicopathological factors, such as age, gender, nodular size, invasive status, central compartment lymph node metastasis (CLNM) and serum thyroid-stimulating hormone (TSH) level, were compared between the various groups of patients.
There were 653 patients with a final diagnosis of HT. More PTC was found in those with HT (58.3%; 381 of 653) than those without HT (2416 of 5456; 44.3%; p < 0.05). The HT patients with co-occurring PTC were more likely to be younger, be female, have smaller nodules and have higher TSH levels than those without PTC. A multivariate analysis indicated that the presence of HT and higher TSH levels were risk factors for a diagnosis of PTC. In the PTC patients, the presence of HT or another benign nodule was a protective factor for CLNM, whereas no significant association was found for TSH levels.
PTC and HT have a close relationship in this region of highly prevalent HT disease. Based on the results of our study, we hypothesise that long-term HT leads to elevated serum TSH, which is the real risk factor for thyroid cancer.
Papillary thyroid carcinoma; Thyroid-stimulating hormone; Hashimoto’s thyroiditis
The ketoisovalerate reductase (EC 184.108.40.206 ) is required for the formation of beauvericin via the nonribosomal peptide synthetase biosynthetic pathway. It catalyzes the NADPH-specific reduction of ketoisovaleric acid to hydroxyisovalerate. However, little is known about the bioinformatics’ data about the 2-Kiv reductase in Fusarium. To date, heterologous production of the gene KivRFp from Fusarium has not been achieved.
The KivRFp gene was subcloned and expressed in Escherichia coli BL21 using the pET expression system. The gene KivRFp contained a 1,359 bp open reading frame (ORF) encoding a polypeptide of 452 amino acids with a molecular mass of 52 kDa. Sequence analysis indicated that it showed 61% and 52% amino acid identities to ketoisovalerate reductase from Beauveria bassiana ATCC 7159 (ACI30654) and Metarhizium acridum CQMa 102 (EFY89891), respectively; and several conserved regions were identified, including the putative nucleotide-binding signature site, GXGXXG, a catalytic triad (Glu405, Asn184, and Lys285). The KivRFp exhibited the highest activity at 35°C and pH 7.5 respectively, by reduction of ketoisovalerate. It also exhibited the high level of stability over wide temperature and pH spectra and in the presence of metal ions or detergents.
A new ketoisovalerate reductase KivRFp was identified and characterized from the depsipeptide-producing fungus F. proliferatum. KivRFp has been shown to have useful properties, such as moderate thermal stability and broad pH optima, and may serve as the starting points for future protein engineering and directed evolution, towards the goal of developing efficient enzyme for downstream biotechnological applications.
2-Kiv Reductase; Beauvericin; Fusarium proliferatum LF061
Diamagnetic levitation is a technique that uses a strong, spatially varying magnetic field to simulate an altered gravity environment, as in space. In this study, using Streptomyces avermitilis as the test organism, we investigate whether changes in magnetic field and altered gravity induce changes in morphology and secondary metabolism. We find that a strong magnetic field (12T) inhibit the morphological development of S. avermitilis in solid culture, and increase the production of secondary metabolites.
S. avermitilis on solid medium was levitated at 0 g*, 1 g* and 2 g* in an altered gravity environment simulated by diamagnetic levitation and under a strong magnetic field, denoted by the asterix. The morphology was obtained by electromicroscopy. The production of the secondary metabolite, avermectin, was determined by OD245 nm. The results showed that diamagnetic levitation could induce a physiological response in S. avermitilis. The difference between 1 g* and the control group grown without the strong magnetic field (1 g), showed that the magnetic field was a more dominant factor influencing changes in morphology and secondary metabolite production, than altered gravity.
We have discovered that magnetic field, rather than altered gravity, is the dominant factor in altered gravity simulated by diamagnetic levitation, therefore care should to be taken in the interpretation of results when using diamagnetic levitation as a technique to simulate altered gravity. Hence, these results are significant, and timely to researchers considering the use of diamagnetic levitation to explore effects of weightlessness on living organisms and on physical phenomena.
Mutant libraries of avermectin-producing Streptomyces avermitilis strains were constructed by different mutagenesis strategies. A metric was applied to assess the mutation spectrum by calculating the distribution of average phenotypic distance of each population. The results showed for the first time that a microgravity environment could introduce larger phenotype distribution and diversity than UV and N-methyl-N-nitro-N-nitrosoguanidine (NTG) could.
Heterogeneous surface expression of Thy-1 in fibroblasts modulates inflammation and may thereby modulate injury and repair. As a paradigm, patients with idiopathic pulmonary fibrosis, a disease with pathologic features of chronic inflammation, demonstrate an absence of Thy-1 immunoreactivity within areas of fibrotic activity (fibroblast foci) in contrast to the predominant Thy-1 expressing fibroblasts in the normal lung. Likewise, Thy-1 deficient mice display more severe lung fibrosis in response to an inflammatory injury than wildtype littermates. We investigated the role of Thy-1 in the response of fibroblasts to the pro-inflammatory cytokine TNF-α. Our study demonstrates distinct profiles of TNF-α-activated gene expression in Thy-1 positive (Thy-1+) and negative (Thy-1−) subsets of mouse embryonic fibroblasts (MEF). TNF-α induced a robust activation of MMP-9, ICAM-1, and the IL-8 promoter driven reporter in Thy-1− MEFs, in contrast to only a modest increase in Thy-1+ counterparts. Consistently, ectopic expression of Thy-1 in Thy-1− MEFs significantly attenuated TNF-α-activated gene expression. Mechanistically, TNF-α activated Src family kinase (SFK) only in Thy-1− MEFs. Blockade of SFK activation abrogated TNF-α-activated gene expression in Thy-1− MEFs, whereas restoration of SFK activation rescued the TNF-α response in Thy-1+ MEFs. Our findings suggest that Thy-1 down-regulates TNF-α-activated gene expression via interfering with SFK- and NF-κB-mediated transactivation. The current study provides a novel mechanistic insight to the distinct roles of fibroblast Thy-1 subsets in inflammation.
Conclusion: Chinese patients have a higher rate of lymphoepithelial carcinoma (LEC) and salivary duct carcinoma (SDC). Comprehensive use of diagnostic modalities, neck dissection, and postoperative radiation will improve the treatment results for salivary gland tumors (SGTs). Objectives: To study the clinicopathological characteristics of SGTs in a Chinese population. Methods: The records of SGT patients operated in a tertiary cancer hospital of China were retrieved. Results: From December 1997 to December 2007, 289 malignant and 887 benign SGTs were operated at Cancer Hospital, Shanghai, China. Pleomorphic adenoma and Warthin's tumor were the most common types of SGT. Mucoepidermoid carcinoma (24.6% of malignant cases) and adenoid cystic carcinoma (18.0%) were the most frequent malignant cases, followed by acinic cell carcinoma (12.1%), LEC (9.7%), and SDC (9.3%). The sensitivity and specificity of ultrasound scan, fine needle aspiration biopsy, and frozen section were 58.3 and 88.6%, 87.2 and 96.7%, 86.9 and 99.6%, respectively. Neck dissections and postoperative radiation were carried out for 48.6 and 48.0% of carcinomas, respectively. The percentage of tumors by pathologic TNM stage were 23.7% for stage I, 32.9% for stage II, 17.3% for stage III, and 26.1% for stage IV. The 5-year overall survival rate was 88.0%.
Lymphoepithelial carcinoma; salivary duct carcinoma; incidence; fine needle aspiration; frozen section