Flexible rotation of linear polarization conversion with a frequency selective surface.

A high-efficiency transmitted polarization converter based on a frequency selective surface (FSS) is proposed in this paper. The FSS-based polarization converter (FSS-PC) is designed based on receiving-via-transmitting (RVT) structure. The receiving and transmitting antenna structures are interconnected by the transmission line, designed in the form of metallized via holes. For any linearly polarized (LP) electromagnetic wave, our proposed FSS-PC has the capability to convert it into another LP electromagnetic wave. This converted wave will have a counterclockwise rotation angle of 2φ relative to the incident wave at 11 GHz. This is achieved by adjusting the relative azimuth φ between the polarization plane of the incident LP wave's electric field and the converter. Meanwhile, the FSS-PC can achieve exceptionally high polarization conversion above -0.30 dB at the central frequency of 11 GHz. Furthermore, as the azimuth of the incident electric field varies, this high-efficiency polarization conversion capability remains stable. The prototype has been fabricated and measured, and the measured results agree well with the simulated ones, thus confirming the effectiveness of the proposed design.

Design of a Reconfigurable Ultra-Wideband Terahertz Polarization Rotator Based on Graphene Metamaterial.

In this work, a reconfigurable ultra-wideband transmissive terahertz polarization rotator based on graphene metamaterial is proposed that can switch between two states of polarization rotation within a broad terahertz band by changing the Fermi level of graphene. The proposed reconfigurable polarization rotator is based on a two-dimensional periodic array of multilayer graphene metamaterial structure, which is composed of metal grating, graphene grating, silicon dioxide thin film, and a dielectric substrate. The graphene metamaterial can achieve high co-polarized transmission of a linearly polarized incident wave at the off-state of the graphene grating without applying the bias voltage. Once the specially designed bias voltage is applied to change the Fermi level of graphene, the polarization rotation angle of linearly polarized waves is switched to 45° by the graphene metamaterial at the on-state. The working frequency band with 45-degree linear polarized transmission remaining above 0.7 and the polarization conversion ratio (PCR) above 90% is from 0.35 to 1.75 THz, and the relative bandwidth reaches 133.3% of the central working frequency. Furthermore, even with oblique incidence at large angles, the proposed device retains high-efficiency conversion in a broad band. The proposed graphene metamaterial offers a novel approach for the design of a terahertz tunable polarization rotator and is expected to be applied in the applications of terahertz wireless communication, imaging, and sensing.

Binary geometric phase metasurface for ultra-wideband microwave diffuse scatterings with optical transparency.

Diffuse scatterings of electromagnetic (EM) waves by thin-thickness metasurfaces have promising prospects in many fields due to their abilities of significantly reducing the backward scatterings of targets. One of the major challenges is to further improve the working bandwidth. Here, we propose a binary geometric phase metasurface with high optical transparency to realize ultra-wideband backward scattering reduction through diffuse scatterings. A multi-layered reflective meta-structure is used as the basic building block while its out-of-phase counterpart is achieved through a geometric rotating operation. The proposed metasurface shows a polarization-insensitive wave-diffusion property with about 10 dB scattering reduction in an ultra-wide frequency band from 3.5 GHz to 16.6 GHz, reaching a fractional bandwidth of 130%. As the experimental demonstration, prototype is fabricated and measured that is in agreement with simulated results. The proposed metasurface provides an efficient way to tailor the exotic scattering features with simultaneously high optical transmittance, which can offer crucial benefits in many practical uses, for example, window stealth applications.

Tannin-based biosorbent encapsulated into calcium alginate beads for Cr(VI) removal.

A composite biosorbent (AC-TFR) prepared by encapsulating tannin-formaldehyde resin (TFR) into calcium alginate (AC) beads was used to remove Cr(VI) from an aqueous solution. Various influencing factors, such as TFR dosage, pH, initial Cr(VI) concentration, contact time, temperature and presence of co-ions in the medium, were investigated. The structures and adsorption performances of the adsorbents were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Compared with other AC-TFR adsorbents, AC-TFR-2 (mass ratio of AC:TFR = 1:1) showed an excellent adsorption capacity based on the efficiency of Cr(VI) removal. The kinetic data fitted to pseudo-second-order and intra-particle diffusion models suggested that the adsorption process was subject to a rate-controlling step. The equilibrium adsorption data fitted well to the Langmuir isotherm model, and the maximum adsorption capacities of AC-TFR-2 were 145.99, 167.22 and 174.52 mg/g at 288, 298, and 308 K, respectively. The thermodynamic parameters revealed that Cr(VI) removal by AC-TFR-2 was endothermic and spontaneous, and the process was chemical adsorption. The mechanism of Cr(VI) removal consisted first of reduction to Cr(III), which has a low toxicity, and then chelation onto AC-TFR-2 via ion exchange.

Full control of conical beam carrying orbital angular momentum by reflective metasurface.

Conical beams have recently attracted much attention due to their excellent performances and potential applications in wireless and satellite-based communication technology. Here, reflective metasurfaces composed of Pancharatnam-Berry (PB) phase elements are demonstrated to have the ability to be flexible and to fully control the conical beam generation with desirable orbital angular momentum (OAM) modes. The theoretical model is developed to analyze the behavior of the conical beam radiation from the reflective metasurface and especially to predict the cone angle, one of the most important factors in the conical beam design. Analysis shows that arbitrary combinations of the cone angle and the OAM mode can be obtained by synthesizing the spatial phase distribution of the metasurface. Finally, two prototypes of microwave metasurfaces, with working bands from 14 GHz to 17 GHz, are fabricated and measured, and the results agree well with the theoretical predictions and simulations. This work demonstrates that metasurfaces can be used for controlling the conical beam generation with desirable OAM modes to potentially enable high capacity data communication, paving the way for novel devices with an appealing low-profile in wireless communication applications.

Optically transparent metasurface Salisbury screen with wideband microwave absorption.

We present an optically transparent broadband microwave absorber based on the concept of metasurface Salisbury screen (MSS). The metasurface with optimized reflection phase profiles is used as the ground plane to excite multi-MSS resonances that are required for achieving continuous wide absorption bandwidth. Meanwhile, by employing indium tin oxide (ITO) film and glass dielectric substrate, high optical transparency and wideband microwave absorption can be obtained simultaneously. Both full-wave electromagnetic simulations and experiments demonstrate that the transparent MSS can perform an efficient absorption over 89% in an ultra-wide frequency band ranging from 4.1 GHz to 17.5 GHz with a sub-wavelength thickness. In addition, good angular performances are observed for all wave polarizations. The proposed MSS may provide a powerful platform for efficiently designing broadband absorption in microwave region with advantages of light weight, thin thickness, and high optical transparency, which could further find potential uses in many real-world applications.

Long noncoding RNAs POLR2E rs3787016 C/T and HULC rs7763881 A/C polymorphisms are associated with decreased risk of esophageal cancer.

Worldwide, rates of esophageal cancer have been keeping highly in recent decades. Genetic variants in multiple cellular pathways might play an important role in altering risk of esophageal carcinoma. In this study, long noncoding RNAs (lncRNAs) functional single nucleotide polymorphisms (SNPs) were investigated in Chinese Han populations. We have genotyped the ANRIL rs2151280 T/C, POLR2E rs3787016 C/T, and HULC rs7763881 A/C SNPs in 380 esophageal squamous cell carcinoma (ESCC) cases and 380 cancer-free controls. POLR2E rs3787016 C/T was associated with a significantly decreased risk for ESCC (CT vs. CC: OR 0.62, 95 % CI 0.44-0.87, P = 0.005; adjusted OR 0.62, 95 % CI 0.44-0.87, P = 0.005). The other SNP, HULC rs7763881, also showed a suggestive association (AC vs. AA: OR 0.70, 95 % CI 0.50-0.98, P = 0.037; adjusted OR 0.69, 95 % CI 0.49-0.97, P = 0.031). ANRIL rs2151280 T/C SNP was not associated with risk of ESCC. In the future, larger studies with other ethnic populations, tissue-specific biological characterization, and detailed individual information should be undertaken to validate current findings.

Variant TP53BP1 rs560191 G>C is associated with risk of gastric cardia adenocarcinoma in a Chinese Han population.

OBJECTIVE: To investigate the association between gastric cardia adenocarcinoma (GCA) and ten functional single nucleotide polymorphisms (SNPs), including TP53BP1 rs560191 G>C, CASP8 rs1035142 G>T, CASP7 rs3127075 G>C, CASP7 rs7907519 C>A, and six C1orf10/CRNN variants. We performed a hospital-based case-control study to evaluate the genetic effects of these SNPs. METHODS: Two hundred and forty-three GCA cases and 476 controls were enrolled in this study. A custom-by-design 48-Plex SNPscan(TM) Kit was used to determine their genotypes. RESULTS: When the TP53BP1 rs560191 GG homozygote genotype was used as the reference group, the GC genotype was associated with a significantly increased risk of GCA. The CC genotype was not associated with the risk of GCA compared with the GG genotype. None of the CASP8 rs1035142 G>T, CASP7 rs3127075 G>C, CASP7 rs7907519 C>A or the six C1orf10/CRNN polymorphisms showed a significant difference in genotype distributions between the cases and the controls. CONCLUSIONS: The results demonstrated that the functional polymorphism TP53BP1 rs560191 G>C might contribute to GCA susceptibility. However, the statistical power of our study was limited. Large, well-designed studies and further functional investigations are needed to confirm our findings.

Interleukin 15 receptor alpha rs2228059 A > C polymorphism decreased risk of gastric cardiac adenocarcinoma in a Chinese population.

Gastric cardiac adenocarcinoma (GCA) is one of the common malignant tumors in the world and has a high incidence in China. Both environmental risk factors and genetic factors might play an essential role in the GCA carcinogenesis. We performed a hospital-based case-control study to evaluate the genetic effects of interleukin 15 (IL15) and IL15 receptor alpha (IL15RA) functional single nucleotide polymorphisms (SNPs) on the pathogenesis of GCA. A total of 243 GCA cases and 476 controls were enrolled in this study. The genotypes were determined using a custom-by-design 48-Plex SNPscan(TM) Kit. When the IL15RA rs2228059 AA homozygote genotype was used as the reference group, the CC genotype was correlated with a significantly decreased risk for GCA (CC vs. AA: adjusted OR = 0.61, 95 % CI = 0.37-0.98, p = 0.042). Our results revealed that functional variant IL15RA rs2228059 A > C might attenuate individual's risk of GCA. However, there was no significant association between the other five IL15 SNPs and GCA susceptibility. This present study demonstrated that IL15RA rs2228059 A > C polymorphism might modify GCA susceptibility. The results were based on a limited sample size; future larger studies with more rigorous designs are warranted to validate our findings.

The variant interleukin 1f7 rs3811047 G>A was associated with a decreased risk of gastric cardiac adenocarcinoma in a Chinese Han population.

To investigate the association between gastric cardiac adenocarcinoma (GCA) and six functional single nucleotide polymorphisms (SNPs) including interleukin 1A (IL1A) rs1800587 C>T, IL1B rs16944 G>A, IL1f7 rs3811047 G>A, IL3 rs40401 C>T, IL3 rs2073506 G>A, and IL7Rα rs6897932 A>G. We performed a hospital-based case-control study to evaluate the genetic effects of these SNPs. A total of 243 GCA cases and 476 controls were enrolled in this study. A custom-by-design 48-Plex SNPscan(TM) kit was used to determine the genotypes. The IL1f7 rs3811047 G>A polymorphism was significantly associated with a decreased risk of GCA either in the single locus analyses or the recessive genetic model. However, there was no significant association between the other five SNPs and GCA risk. These results elucidated that the functional polymorphism, IL1f7 rs3811047 G>A, might contribute to GCA susceptibility. However, the statistical power of our study was limited, large well-designed studies and further functional investigations are needed to confirm our findings.

NQO1 rs1800566 C>T polymorphism was associated with a decreased risk of esophageal cancer in a Chinese population.

BACKGROUND. Esophageal cancer was the fifth most commonly diagnosed cancer and the fourth leading cause of cancer-related death in China in 2009. Esophageal squamous cell carcinoma (ESCC) accounts for more than 90% of esophageal cancers. Genetic factors may play an important role in the carcinogenesis of ESCC. METHODS. We conducted a hospital-based case-control study to evaluate functional NAD(P)H: quinone oxidoreductase 1 (NQO1) rs1800566 C>T and NQO2 rs2070999 G>A single-nucleotide polymorphisms on the risk of ESCC. A total of 629 patients with ESCC and 686 controls were recruited for this study. The genotypes were determined using the ligation detection reaction method. RESULTS. When the NQO1 rs1800566 CC homozygote genotype was used as the reference group, the TT genotype was associated with a significantly decreased risk of ESCC. In the recessive model, when the NQO1 rs1800566 CC/CT genotypes were used as the reference group, the TT homozygote genotype was associated with a 31% decreased risk of ESCC. A significantly decreased risk of ESCC was evident in patients with the NQO1 rs1800566 C>T polymorphism among females, those of a younger age (<63 years), those who had never smoked, those who consumed alcohol and those who did not. There was no association found between the NQO2 rs2070999 G>A polymorphism and ESCC risk. CONCLUSION. The NQO1 rs1800566 TT genotype was associated with a decreased risk of ESCC in a Chinese population. The association was evident among female patients, younger patients, patients who had never smoked, patients who consumed alcohol and those who did not. These findings need to be confirmed by repeating the study in a larger cohort of patients.

IL-15 receptor alpha rs2228059 A>C polymorphism was associated with a decreased risk of esophageal cancer in a Chinese population.

Esophageal cancer is the sixth leading cause of cancer-related deaths worldwide. Esophageal cancer is very aggressive; genetic polymorphisms may explain in part the individual differences in esophageal cancer susceptibility. We conducted a hospital based case-control study to evaluate the genetic effects of functional single nucleotide polymorphisms (SNPs) in the interleukin (IL)-15 and IL-15 receptor alpha (IL-15RA) gene on the development of esophageal cancer. A total of 380 esophageal squamous cell carcinoma (ESCC) cases and 380 controls were recruited for this study. The genotypes were determined using a custom-by-design 48-Plex SNPscan(TM) kit. The IL-15RA rs2228059 A>C polymorphism was associated with a decreased risk of ESCC in a recessive genetic model; However, there was no significant association between the other five SNPs and ESCC risk. Stratified analyses indicated a significantly decreased risk of ESCC associated with the IL-15RA rs2228059 A>C polymorphism was evident among male, older, non-smoker, and non-drinker patients. These findings indicated that the functional polymorphism, IL-15RA rs2228059 A>C, might contribute to ESCC susceptibility. However, the statistical power of our study was limited because of the moderate sample size and absence of a validation cohort. Large well-designed studies are warranted to confirm our findings.

Caspase8 rs1035142 G>T polymorphism was associated with an increased risk of esophageal cancer in a Chinese population.

Esophageal cancer is one of the ten most common cancers in the world and has poor prognosis. Apoptosis is considered a fundamental component in cancer pathogenesis. We conducted a hospital-based case-control study to evaluate the genetic effects of 16 apoptosis associated single nucleotide polymorphisms (SNPs) on esophageal cancer development. A total of 380 esophageal squamous cell carcinoma (ESCC) cases and 380 controls were recruited for this study. Genotypes were determined using a custom-by-design 48-Plex SNPscan™ Kit. The caspase8 (CASP8) rs1035142 G>T polymorphism was associated with increased risk of ESCC by heterozygote comparison, homozygote comparison, a dominant genetic model and a recessive genetic model. However, no significant association was detected between the other 15 SNPs and ESCC risk. Stratified analyses indicated a significantly increased risk of ESCC associated with CASP8 rs1035142 G>T polymorphism was evident among all subgroups. These findings indicated that the functional polymorphism CASP8 rs1035142 G>T might contribute to ESCC susceptibility.

Association of LAMA1 Single-Nucleotide Polymorphisms with Risk of Esophageal Squamous Cell Carcinoma among the Eastern Chinese Population.

Introduction: LAMA1, also known as laminin subunit α1, is a member of the laminin family, which is widely reported to be a key basement membrane molecule that affects various biological activities and is associated with many kinds of diseases. We aimed to investigate the association between LAMA1single-nucleotide polymorphisms and the occurrence and progression of esophageal squamous cell carcinoma in the Chinese population. Method: 2,186 participants were collected retrospectively between October 2008 and January 2017, including 1,043 ESCC patients and 1,143 noncancer patients. A 2 mL blood sample was obtained intravenously for the LDR for SNP analysis. The 6 SNP loci of LAMA1 were selected and examined. We analyzed the association of several genetic models of 6 LAMA1 SNP loci, sex, age, smoking and drinking status, and the occurrence of esophageal squamous cell carcinoma. Results: In the rs62081531 G > A locus, genotype GA was a protective factor for ESCC compared with GG (OR: 0.830, P=0.046), especially among the younger and nondrinkers. At rs607230 T > C, genotype TC was linked with a lower risk of ESCC compared with TT. (OR: 0.613, P=0.034). Haplotype Frequencies revealed that Ars62081531Grs621993Ars539713Trs566655Ars73938538Crs607230 (OR: 0.803, P=0.028) and Grs62081531Grs621993Ars539713Trs566655Crs73938538Crs607230 (OR: 0.679, P=0.010) were strongly associated with lower susceptibility of ESCC. Conclusion: The LAMA1 rs62081531, rs539713, rs566655, and rs607230 polymorphisms were demonstrated to be related to susceptibility to ESCC in the Chinese population. LAMA1 SNPs may have a significant impact on the occurrence of esophageal cancer and may serve as potential diagnostic biomarkers.

Replication study of PLCE1 and C20orf54 polymorphism and risk of esophageal cancer in a Chinese population.

Esophageal cancer is one of the most aggressive cancers in the world. Recent large-scale genome-wide association studies (GWAS) reported that functional genetic variations in the phospholipase C epsilon gene (PLCE1) were strongly associated with risk of esophageal squamous cell carcinoma (ESCC) and gastric cardia adenocarcinoma (GCA) in Chinese population. For C20orf54 rs13042395 genotype and risk of esophageal cancer, the results were inconsistent. We conducted a replication case-control study to evaluate the genetic effects of these two functional single nucleotide polymorphisms (SNPs) on the development of esophageal cancer. A total of 380 cases and 380 controls were recruited for this study. The genotypes were determined by matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF MS). The variant alleles of the functional polymorphism, PLCE1 rs2274223 SNP was associated with the increased risk of esophageal cancer [adjusted odds ratio (OR) = 1.95, 95 % confidence interval (CI) = 1.05-3.59 for PLCE1 rs2274223 GG vs. AA]. However, there was no significant association between the C20orf54 rs13042395 genotype and esophageal cancer risk (adjusted OR = 0.99, 95 % CI = 0.63-1.57 for C20orf54 rs13042395 TT vs. CC). Stratified analyses indicated a significantly increased risk of esophageal cancer associated with the PLCE1 rs2274223 AG genotype was more evident among females, younger patients and never drinkers, compared with the PLCE1 rs2274223 AA genotypes. Stratified analyses also indicated a significantly increased risk of esophageal cancer associated with the PLCE1 rs2274223 GG genotype was more evident among never smokers and never drinkers compared with the PLCE1 rs2274223 AA genotypes. These findings indicated that functional polymorphisms PLCE1 rs2274223 might contribute to esophageal cancer susceptibility.

Variant allele of CHEK2 is associated with a decreased risk of esophageal cancer lymph node metastasis in a Chinese population.

Growing evidence suggests that the checkpoint kinase 2 (CHEK2) signaling pathway occupies a central position in the signaling networks of DNA-damage signaling. Many functional and molecular epidemiological studies have evaluated the association between genetic variants of CHEK2 and various cancers. To evaluate the relationship between CHEK2 functional genetic variants and esophageal cancer risk and the risk of lymph node metastasis among a Chinese population. We genotyped CHEK2 rs738722, rs2236141 and rs2236142 single nucleotide polymorphisms (SNPs) using the matrix assisted laser desorption/ionization time-of-flight mass spectrometry assay in a case-controlled study, including 380 esophageal cancer cases and 380 healthy controls in a Chinese population. We found that none of the three polymorphisms achieved significant difference in their distributions between esophageal cancer cases and controls. Multiple logistic regression analyses revealed that esophageal cancer risk was not associated significantly with the variant genotypes of the three CHEK2 polymorphisms as compared with their wild-type genotypes. However, we found that functional variant rs738722 and rs2236142 in CHEK2 might contribute to susceptibility to lymph node metastasis. Our data did not support a significant association between CHEK2 SNPs and the risk of esophageal cancer. Functional variant CHEK2 rs738722 and rs2236142 might contribute to lymph node metastasis susceptibility. The CT allele of SNP rs738722 and the GC allele of SNP rs2236142 might be a protective factor of the risk for lymph node metastasis of esophageal cancer.

A Connexin-Based Biomarker Model Applicable for Prognosis and Immune Landscape Assessment in Lung Adenocarcinoma.

Purpose: Gap junction protein (Connexin) family is the basic unit of cellular connection, whose multiple members were recently demonstrated to be associated with tumor progression. However, the expression pattern and prognostic value of connexin in lung adenocarcinoma (LUAD) have not yet been elucidated. Methods: Consensus cluster algorithm was first applied to determine a novel molecular subtype in LUAD based on connexin genes. The differentially expressed genes (DEGs) between two clusters were obtained to include in Cox regression analyses for the model construction. To examine the predictive capacity of the signature, survival curves and ROC plots were conducted. We implemented GSEA method to uncover the function effects enriched in the risk model. Moreover, the tumor immune microenvironment in LUAD was depicted by CIBERSORT and ssGSEA methods. Results: The integrated LUAD cohort (TCGA-LUAD and GSE68465) were clustered into two subtypes (C1 = 217 and C2 = 296) based on 21 connexins and the clinical outcomes of LUAD cases in the two clusters showed remarkable discrepancy. Next, we collected 222 DEGs among two subclusters to build a prognostic model using stepwise Cox analyses. Our proposed model consisted of six genes that accurately forecast patient outcomes and differentiate patient risk. GSEA indicated that high-risk group was involved in tumor relevant pathways were activated in high-risk group, such as PI3K/AKT signaling, TGF-ß pathway, and p53 pathway. Furthermore, LUAD cases with high-risk presented higher infiltration level of M2 macrophage and neutrophil, suggesting high-risk group were more likely to generate an immunosuppressive status. Conclusion: Our data identified a novel connexin-based subcluster in LUAD and further created a risk signature which plays a central part in prognosis assessment and clinical potency.

Case-control study on TP73 rs1801173 C > T gene polymorphism and susceptibility to gastric cancer in a Chinese Han population.

BACKGROUND: This study investigated the role of TP73 gene polymorphism, rs1801173on risk of gastric cancer. METHODS: We conducted a case-controlled study including 577 primary gastric cancer and 678 normal control cases. The target gene fragment was amplified using PCR using blood samples collected from patients. Allele analysis and genotyping were performed using snapshot method. RESULTS: The findings showed that the control group had consistent genotype frequency distribution and presented Hardy-Weinberg equilibrium. The results showed no significant differences in sex, drinking history and age distributions between subjects with the polymorphism and subjects in the control group. Smoking status was correlated with incidence of gastric cancer (P = 0.006). The rs1801173 locus of TP73 gene contained 3 genotypes including: TT, CT, and CT. Logistic regression analysis showed that distribution of recessive model and dominant model was comparable between the two groups before (P = 0.688; 0.937) or after (P = 0.703; 0.990) adjusting for confounders. The distribution frequency in case group was not significantly different relative to that of the control group (P = 0.763). CONCLUSION: Smoking can independently influence the risk of gastric cancer. TP73 gene rs1801173 polymorphism was not significantly correlated with risk of gastric cancer.

The Single Nucleotide Polymorphisms of AP1S1 are Associated with Risk of Esophageal Squamous Cell Carcinoma in Chinese Population.

Background: The σ1A subunit of the adaptor protein 1 (AP1S1) participates in various intracellular transport pathways, especially the maintenance of copper homeostasis, which is pivotal in carcinogenesis. It is therefore rational to presume that AP1S1 might also be involved in carcinogenesis. In this hospital-based case-control study, we investigated the genetic susceptibility to ESCC in relation to SNPs of AP1S1 among Chinese population. Methods: A database containing a total of 1303 controls and 1043 ESCC patients were retrospectively studied. The AP1S1 SNPs were analyzed based on ligation detection reaction (LDR) method. Then, the relationship between ESCC and SNPs of AP1S1 was determined with a significant crude P<0.05. Then the logistic regression analysis was used for the calculation for adjusted P in the demographic stratification comparison if a significant difference was observed in the previous step. Results: AP1S1 rs77387752 C>T genotype TT was an independent risk factor for ESCC, while rs4729666 C>T genotype TC and rs35208462 C>T genotype TC were associated with a lower risk for ESCC, especially in co-dominant model and allelic test for younger, male subjects who are not alcohol-drinkers nor cigarette smokers. Conclusion: AP1S1 rs77387752, rs4729666 and rs35208462 polymorphisms are associated with susceptibility to ESCC in Chinese individuals. AP1S1 SNPs may exert an important role in esophageal carcinogenesis and could serve as potential diagnostic biomarkers.

Research Progress of Circular RNA in Gastrointestinal Tumors.

circular RNA (circRNA) is a closed ring structure formed by cyclic covalent bonds connecting the 5'-end and 3'-end of pre-mRNA. circRNA is widely distributed in eukaryotic cells. Recent studies have shown that circRNA is involved in the pathogenesis and development of multiple types of diseases, including tumors. circRNA is specifically expressed in tissues. And the stability of circRNA is higher than that of linear RNA, which can play biological roles through sponge adsorption of miRNA, interaction with RNA binding protein, regulation of gene transcription, the mRNA and protein translation brake, and translation of protein and peptides. These characteristics render circRNAs as biomarkers and therapeutic targets of tumors. Gastrointestinal tumors are common malignancies worldwide, which seriously threaten human health. In this review, we summarize the generation and biological characteristics of circRNA, molecular regulation mechanism and related effects of circRNA in gastrointestinal tumors.