Diagnostic advantages of transrectal ultrasound with gastrointestinal agent instillation for rectal adenoma and early-stage rectal cancer: comparison of conventional transrectal ultrasound techniques.

Background: Despite being a major focus of medical research for decades, rectal cancer remains a major threat to human health. This study aimed to compare and analyze the diagnostic value of transrectal ultrasonography (TRUS) for rectal adenoma and early-stage rectal cancer before and after gastrointestinal agent instillation. Methods: In this prospective study, patients diagnosed with rectal adenomas and early-stage rectal cancer by ultrasound were randomly selected for inclusion. All patients underwent ultrasound examination at the Outpatient Department of the First Affiliated Hospital of China Medical University and underwent surgical treatment at the First Affiliated Hospital of China Medical University. Patients with a lesion located 13 cm or more from the edge of the anus, or history of surgery, and a history of radiation and chemotherapy were excluded. A gastrointestinal agent was directly instilled into the rectal cavity during conventional TRUS to compare and analyze the display of rectal lesions before and after such instillation and to evaluate the infiltration depth of rectal lesions. These findings were compared to the pathological findings to determine the diagnostic efficacy. Results: Both the conventional TRUS and TRUS with gastrointestinal agent instillation were able to show the rectal wall structure and rectal lesions; the detection rate of rectal lesions of the former was 75.0%, and that of the latter was 97.1% (P<0.001). Of the 27 rectal adenomas, conventional TRUS detected 10, and TRUS with gastrointestinal agent instillation detected 25 lesions. The accuracy [90.54%; 95% confidence interval (CI): 81.48-96.11%; P=1.05E-08], specificity (87.88%; 95% CI: 71.80-96.60%; P=1.09E-05), and sensitivity (92.68%; 95% CI: 80.08-98.47%; P=1.05E-08) of TRUS in diagnosing early-stage rectal cancer were consistent with the pathological findings (P<0.001). The accuracy (95.95%, 95% CI: 88.61-99.16%; P=3.82E-11), specificity (93.94%, 95% CI: 79.77-99.26%; P=1.31E-07), and sensitivity (97.56%, 95% CI: 87.15-99.94%; P=3.82E-11) of TRUS after gastrointestinal agent infusion in diagnosing early-stage rectal cancer were consistent with the pathological findings (P<0.001). The specificity (87.88%; 95% CI: 71.80-96.60%; P=1.09E-05) of TRUS in diagnosing rectal adenomas was consistent with the pathological finding (P<0.001), but the accuracy (65%; 95% CI: 51.60-76.87%; P=0.25) and sensitivity (37.04%, 95% CI: 19.40-57.63%; P=0.25) were not (P>0.05). Meanwhile, the accuracy (93.33%; 95% CI: 83.80-98.15%; P=5.65E-06), specificity (93.94; 95% CI: 79.77-99.26%; P=1.31E-07), and sensitivity (92.59%; 95% CI: 75.71-99.09%; P=5.65E-06) of TRUS after gastrointestinal agent infusion in diagnosing rectal adenomas were consistent with the pathological findings (P<0.001). Conclusions: TRUS with gastrointestinal agent instillation had significantly improved accuracy in diagnosing early-stage rectal cancer and detecting intrarectal adenomatoid lesions.

Clinical value of contrast-enhanced ultrasonography in focal hypoechogenic lesions of thyroid.

OBJECTIVE: The objectives of this study were to analyze the accuracy of contrast-enhanced ultrasonography (CE-US) in diagnosing focal hypoechogenic lesions of the thyroid (FHLT), and to explore the clinical value of CE-US in the diagnosis of FHLT. METHODS: Patients undergoing CE-US and ultrasound-guided fine needle aspiration (US-FNA) of FHLT at First Hospital of China Medical University between January 2017 and December 2018 were selected for the study; this included patients with papillary thyroid carcinoma (PTC), subacute thyroiditis (SAT) and focal Hashimoto thyroiditis (FHT). All patients underwent color Doppler ultrasonography (CD-US) after which thyroid image reporting and data system (TI-RADS) grading were done. Then, each patient underwent CE-US and US-FNA. The results of the CE-US were analyzed using descriptive statistics. The cytopathological results from the US-FNAs were the gold standard used to confirm the diagnoses. RESULTS: A total of 56 patients were selected for the study. In the PTC group (n = 16), grading was as follows: TI-RADS4a, n = 3; TI-RADS4b, n = 12; and TI-RADS4c, n = 1. More patients with PTC showed heterogeneous hypoenhancement (n = 15) than heterogeneous isoenhancement (n = 1) on CE-US. In the SAT group (n = 24), grading was as follows: TI-RADS3, n = 1; TI-RADS4a, n = 18; TI-RADS4b, n = 5. Fewer patients with SAT showed heterogeneous hypoenhancement (n = 2) than heterogeneous isoenhancement (n = 22) on CE-US. In the FHT group (n = 16), grading was as follows: TI-RADS3, n = 1; TI-RADS4a, n = 11; TI-RADS4b, n = 4. Of those in the FHT group, one patient showed heterogeneous isoenhancement, one patient showed heterogeneous hypoenhancement, and 14 showed uniform isoenhancement on CE-US. The diagnostic accuracy of CD-US alone differed significantly from that of CD-US + CE-US (p < 0.05). CONCLUSION: CE-US has a high diagnostic accuracy for FHLT and can be used to identify PTC, SAT, and FHT.

Curcumin combined with low-intensity ultrasound suppresses the growth of glioma cells via inhibition of the AKT pathway.

Malignant glioma is the most lethal form of brain cancer, and effective therapeutic modalities remain unavailable to date. We aim to investigate whether low-dose curcumin combined with low-intensity ultrasound (LIUS) effectively suppresses the growth of glioma cells and elucidate the underlying mechanisms. Glioma cells were treated with LIUS and curcumin. Subsequently, the effects of LIUS and curcumin on glioma cells were determined by CCK-8 assay, EdU assay, and flow cytometry analysis, respectively. Western blot analysis was performed to examine the levels of apoptosis-associated proteins and the proteins related to the AKT pathway. The proliferation assay showed that combined treatment with LIUS and curcumin synergistically decreased proliferation in glioma cells. And cell apoptosis was promoted after LIUS-curcumin combination treatment, characterized by the occurrence of more apoptotic cells and a significant increase in Bax level and attenuated Bcl-2 expression. Moreover, the role of LIUS-curcumin combination in downregulation of the AKT pathway was observed. The AKT pathway activator SC79 reversed apoptosis and anti-proliferation induced by combined treatment with LIUS and curcumin. Our findings show that LIUS in combination with low-dose curcumin synergistically suppresses the growth of glioma cells via inhibition of the AKT pathway. LIUS plus curcumin may be a promising therapeutic strategy for preventing glioma growth.

Associations of BRAF V600E, clinical pathology and imaging factors with the recurrence rate of papillary thyroid microcarcinoma.

In the present study, the recurrence rate of papillary thyroid microcarcinoma (PTMC) was assessed by analyzing postoperative follow-up data of affected patients and its associations with BRAF V600E, clinical pathology and imaging factors were explored. A total of 506 patients with PTMC were selected who underwent surgery from January 2014 to March 2016. The maximal diameter of thyroid nodules was ≤1 cm and all patients who underwent BRAF V600E testing and evaluation for lymph node metastasis. Postoperatively, each patient was regularly followed up to detect recurrence. Categorical variables were comparatively analyzed using univariate Cox linear regression analysis to screen for protective and adverse factors influencing recurrence of PTMC. A stepwise Cox proportional hazards regression model analysis was performed to explore risk factors affecting recurrence. Among the 506 patients, 477 were followed up, 29 were lost to follow-up and 26 patients experienced recurrence. The 5-year recurrent rate of PTMC was 5.45%. The univariate Cox regression analysis indicated that PTMC recurrence was influenced by BRAF V600E, sex, multifocality, capsular invasion and lateral cervical lymph node metastasis (P<0.05), but not by age, tumor location on the thyroid, size, single central lymph node metastasis, distant metastasis and operative approach (P>0.05). The significant factors associated with recurrent PTMC were subjected to stepwise multivariate Cox proportional hazards regression model analysis and the results indicated that BRAF V600E, sex, multifocality and lateral cervical lymph node metastasis were independent factors influencing recurrence in patients with PTMC, with a statistically significant difference (P<0.05). In conclusion, BRAF V600E, sex, multifocality and lateral cervical lymph node metastasis are independent risk factors for recurrent PTMC.

Greater Omentum Imaging-Reporting and Data System: establishing the grade of benign and malignant lesions of the greater omentum using ultrasonography.

OBJECTIVE: To establish Greater Omentum Imaging-Reporting and Data System (GOI-RADS) to evaluate the possibility of omental diseases being malignant. METHOD: A retrospective analysis was made of 883 patients who had undergone biopsy of the greater omentum in our center from October 2009 to October 2019. Twelve parameters of ultrasonographic images were evaluated, and the odds ratio of each group calculated. We assigned scores for the direct signs (omental echo, omental structure, and omental nodules) and indirect signs (separation of ascites, echo of ascites, mesenteric lymph nodes, and thickening of parietal peritoneum) of omental lesions. We created an omental score (OS) for each patient and receiver operating characteristic (ROC) curve to analyze its effectiveness in the differential diagnosis of benign and malignant omental diseases. RESULTS: The OS was divided into ≤5, 6, 7, 8, 9, 10, 11, 12, 13, and ≥ 14 points, and the malignant rate was 0, 1.85, 5.56, 30.36, 37.25, 87.72, 96.72, 98.28, 99.08, and 100%, respectively. The area under the ROC curve (AUC) was 0.976. When taking 10 points as the cutoff value to diagnose benign and malignant omental diseases, the sensitivity and specificity was 93.85 and 98.21%, respectively. A grading system was established: grade 1: omental score ≤ 5, malignant rate 0%; grade 2: omental score 6-7, malignant rate ≤ 5.56%; grade 3: omental score 8--9, malignant rate ≤ 37.25%; grade 4: omental score ≥ 10, malignant rate ≥ 87.72. CONCLUSION: GOI-RADS had high sensitivity and specificity in the differential diagnosis of benign and malignant omental lesions. We believe that GOI-RADS will aid the diagnosis of omental diseases based on objective and accurate interpretation of ultrasound features, and also to promote the ultrasonography of omental diseases in clinical application.

Correlation between FAK and EGF-Induced EMT in Colorectal Cancer Cells.

Epithelial-mesenchymal transition (EMT) plays an important role in the invasion and metastasis of colorectal cancer, which is mediated by FAK and EGF. However, whether FAK participates in EMT in colorectal cancer cells through the EGF/EGFR signaling pathway remains unknown. The aim of this study was to investigate the effector mechanisms of FAK in the process of EGF-induced EMT in colorectal cancer cells and to determine whether miR-217 is involved in this process. Caco-2 cancer cells were routinely cultured with and without treatment with 100 ng/mL EGF, and changes in cell morphology were observed using an inverted microscope. In addition, a transwell assay was used to detect cell migration under the condition of EGF treatment. The expression of FAK, pFAK, E-cadherin, vimentin, and ß actin was assessed by western blotting, and the expression of miR-217 was assessed using real-time PCR. We found that EGF induced EMT in colorectal cancer cells and enhanced cell migration and invasion ability. Moreover, FAK was involved in the EGF-induced EMT of colorectal cancer cells. EGF upregulated the expression of E-cadherin in colorectal cancer cells by activating FAK, and miR-217 was found to participate in EGF-induced EMT in colorectal cancer cells. Our findings indicate that EGF induces EMT in colorectal cancer cells by activating FAK, and miR-217 is involved in the EGF/FAK/E-cadherin signaling pathway.

Diagnostic Accuracy of Contrast-Enhanced Ultrasonography in Papillary Thyroid Microcarcinoma Stratified by Size.

We explored the diagnostic accuracy of ultrasonography (US) in papillary thyroid microcarcinoma (PTMC), studying nodular growths according to size via 3-D color Doppler US (3-DCDUS) and contrast-enhanced US (CEUS). A total of 109 patients undergoing CEUS and surgery of thyroid nodules at the First Hospital of China Medical University between January 2017 and December 2018 were selected for the study, including 77 with post-operative pathologically confirmed PTMC (test group) and 32 with nodular goiter (controls). All nodules were ≤1.0 cm in maximum diameter. After 3-DCDUS, each patient underwent Thyroid Imaging Reporting and Data System (TI-RADS) grading. In both groups, receiver operating characteristic curve analysis of anteroposterior (AP) nodule diameters was conducted, establishing a cutpoint for probable malignancy by CEUS. In the test group (n = 77), grading was as follows: TI-RADS 4a, 23; TI-RADS 4b, 40; TI-RADS 4c, 14. More patients had heterogeneous enhancement or hypo-enhancement (n = 55) than uniform hyper-enhancement or uniform iso-enhancement (n = 22) by contrast-enhanced ultrasonography (CEUS). Control group (n = 32) grading was as follows: TI-RADS 3, 1; TI-RADS 4, 21; TI-RADS 4b, 10. Fewer patients had heterogeneous enhancement or hypo-enhancement (n = 12) than uniform hyper-enhancement or uniform iso-enhancement (n = 20) by CEUS. The diagnostic accuracy of 3-DCDUS or CEUS differed significantly from that of 3-DCD-US + CEUS (p < 0.05), whereas 3-DCDUS and CEUS performed similarly (p > 0.05). At AP diameters of 0.66 cm, the Youden index for diagnosing malignancy by CEUS was maximal. When nodules below this threshold were excluded, both CEUS and 3-DCDUS + CEUS improved significantly in diagnostic accuracy (p < 0.05). CEUS is useful in determining the status (benign vs. malignant) of thyroid nodules, with significantly better accuracy at AP diameters ≥0.66 cm.

The anteroposterior diameter of nodules in the risk assessment of papillary thyroid microcarcinoma.

This study investigates the application of ultrasound, especially the anteroposterior diameter of nodules in the malignancy and metastasis risk assessment of papillary thyroid microcarcinoma through a retrospective analysis of 500 cases of thyroid nodule ultrasonography.We selected 500 patients with thyroid nodules (maximum nodule diameter ≤2.0 cm) that had been diagnosed clinically and graded TI-RADS 4c by ultrasonography and surgically treated. Among these, there were 258 cases of pathologically diagnosed papillary thyroid microcarcinoma, 72 cases of nodular goiter or adenoma, 137 cases of papillary thyroid carcinoma, 28 cases of acinar cell carcinoma, and 5 cases of undifferentiated carcinoma. In all cases, color Doppler ultrasonography had been performed preoperatively to determine the size and number of nodules, surrounding lymph node metastasis, and TI-RADS grading. Cases of papillary thyroid microcarcinoma diagnosed by pathology were selected as the study group, and cases of nodular goiter or adenoma as the control group. Each group was further subdivided based on the anteroposterior, vertical, and transverse nodule diameters. Intergroup statistical analysis was also performed. Receiver operating characteristic (ROC) curve analysis was conducted on the study and control groups based on the anteroposterior nodule diameters, and the optimal critical value for malignancy risk was determined. Thyroid nodules in the study group were divided into groups based on the presence or absence of lymph node metastasis. Based on the anteroposterior nodule diameter, ROC curve analysis was performed, and the optimal critical value for metastasis risk was determined.There were 500 cases of malignant nodules diagnosed by ultrasound. Among these, there were 428 cases of malignant nodules diagnosed by pathology. The coincidence rate of the ultrasound diagnosis with pathological diagnosis was 85.60%. While, interestingly, There was a significant statistical difference between the study and control groups based on the anteroposterior nodule diameter. When the anteroposterior nodule diameter was 0.7 cm, sensitivity of malignant diagnosis was 76.70% and specificity of that was 66.70%, and the Youden index was the highest. The lymph node metastasis rate for papillary thyroid microcarcinoma was 13.95%. Within this group, the lymph node metastasis rate for nodules ≥0.9 cm (anteroposterior diameter) was 38.46%. When the anteroposterior nodule diameter was equal to 0.9 cm, sensitivity of diagnosis was 83.30%, and specificity of that was 77.80%, and the Youden index was the highest.The anteroposterior diameter of thyroid nodules is more suitable for assessing their malignancy with 0.7 cm, which can be used as the critical value. Nodules ≥ 0.7 cm require surgical treatment, and those <0.7 cm can be observed. An anteroposterior diameter of 0.9 cm can be used as the critical value for assessing the metastasis risk of malignant thyroid nodules. During surgery, the dissection of central cervical lymph nodes is required for nodules ≥0.9 cm.

Clinical Application of Real-Time Shear Wave Elastography in Identifying the Histological Components of Parotid Adenolymphoma.

OBJECTIVE: This study aimed to investigate the relationship between the elastic modulus and the histological components of parotid adenolymphoma by using real-time shear wave elastography. METHODS: A total of 157 patients, histologically confirmed as having parotid adenolymphoma, were enrolled in the study. The maximum and the mean elastic modulus of the parotid mass were measured by using preoperative shear wave elastography. Parotid adenolymphoma was histopathologically subdivided into different types based on the relative proportion of stromal to cellular components. RESULTS: The maximal elasticity of parotid adenolymphoma ranged from 20.67 to 160.90 kPa, and the mean elasticity was 83.18 ± 39.15 kPa. The maximal elasticity of the 3 types of parotid adenolymphoma was 34.21 to 155.20, 20.67 to 104.20, and 45.89 to 160.90 kPa, respectively. The mean elasticity of the 3 types of parotid adenolymphoma was 89.16 ± 40.62, 63.24 ± 28.07, and 111.10 ± 37.85 kPa, respectively. The difference in the maximal elasticity among 3 groups was significant (P < 0.01). There was no significant difference in maximal elasticity of type II and type III as compared with type I adenolymphoma (P > 0.05). The maximal elasticity of type III adenolymphoma was significantly higher than that of type II (P < 0.05, t = 3.12). CONCLUSION: Shear wave elastography depicts parotid adenolymphoma with a variable appearance because of the relative proportions of stromal to cellular contents in the mass.

TRPA1 contributed to the neuropathic pain induced by docetaxel treatment.

Peripheral mechanical neuropathic pain is a serious side effect of docetaxel chemotherapy for cancer. However, the underlying mechanism for this side effect is unknown. In the present study, we found that docetaxel treatment induced mechanical allodynia in rats. We further revealed that the transient receptor potential ankyrin subtype 1 protein (TRPA1) protein level is upregulated and the TRPA1 activator allyl isothiocyanate induced larger ion currents in the dorsal root ganglion neurons from the docetaxel treated rats. In addition, application the TRPA1 blocker Ap18 reversed the docetaxel-induced mechanical hypersensitivity. We suggest that the docetaxel-induced mechanical allodynia is mediated by upregulation of TRPA1 in dorsal root ganglion neurons.

Expression and regulatory effects of microRNA-182 in osteosarcoma cells: A pilot study.

The aim of the present study was to evaluate the expression level of microRNA-182 (miRNA-182) in human osteosarcoma (OS) MG-63 cells and OS tissues, and to elucidate the effect of miRNA-182 on the biological activity of tumors. In the present study, the expression of miRNA-182 in human OS MG-63 cells, OS tissues and normal osteoblast hFOB1.19 cells was determined using quantitative polymerase chain reaction. Subsequently, a miRNA-182 mimic and inhibitor were utilized to regulate the expression level of this miRNA in MG-63 cells. Cell viability and proliferation were examined using cell counting kit-8 assays, and cell apoptosis was detected by flow cytometry. Cell invasion and migration assays were performed using Transwell chambers to analyze the biological functions of miRNA-182 in vitro. The present study demonstrated that the expression level of miRNA-182 in MG-63 cells and OS tissues was significantly increased compared with the hFOB1.19 cell line (P<0.05). The present study successfully performed cell transfections of miRNA-182 inhibitor and miRNA-182 mimic into MG-63 cells and achieved the desired transfection efficiency. The present study confirmed that upregulation of miRNA-182 promotes cell apoptosis and inhibits cell viability, proliferation, invasion and migration. The present findings additionally demonstrated that miRNA-182 is a tumor suppressor gene in OS. Therefore, regulating the expression of miRNA-182 may affect the biological behavior of OS cells, which suggests a potential role for miRNA-182 in molecular therapy for malignant tumors.

Clinical Implications of TßRII Expression in Breast Cancer.

OBJECTIVE: To explore the relationship between TßRII [type II TGFß (transforming growth factor ß) receptor] expression and clinicopathological characteristics, and to evaluate the prognostic significance of TßRII expression in breast cancer. METHODS: Clinicopathological data and prognostic information of 108 patients with histologically confirmed breast cancer who were surgically treated at China Medical University between January 2007 and September 2008 were reviewed and the association between the clinicopathological characteristics and TßRII expression was analyzed by chi-square test and multivariate analysis. The expression of TßRII was assessed by immunohistochemistry. RESULTS: Of the 108 patients, 60 cases were TßRII positive and 48 cases were negative. There was no significant association between TßRII expression of the patients older than 40 years and that of the younger than 40 years (56.0% vs 50.0%; P = 0.742). The TßRII expression rate was significantly increased in patients with lymph node metastasis compared to those without lymph node metastasis (67.40% vs 46.8%; P = 0.033). Statistically significant relationships were found between increasing tumor clinical stage and high TßRII expression (P = 0.011). TßRII expression was not associated with the expression of ER(estrogen receptor), PR, (progesterone receptor), Her-2 (human epidermal growth factor receptor 2) (P = 0.925,P = 0.861, and P = 0.840, respectively). Patients with high TßRII expression showed poorer 5-year disease-free survival (DFS) compared to those with low expression (66.7% vs 45.6%; P = 0.028) by univariate analysis. Survival analysis demonstrated that TßRII was associated with poor DFS (P = 0.011). Subgroup analysis revealed that TßRII expression was associated with shorter DFS in patients with lymph node metastasis, ER-positive, PR-positive or Her-2-negative tumors (P = 0.006, P = 0.016, P = 0.022, and P = 0.033, respectively). Cox regression analysis revealed that high TßRII expression was related to poor 5-year DFS, and it was an independent factor for predicting the poor outcome for breast cancer patients (P = 0.016). CONCLUSIONS: High levels of TßRII expression were associated with lymph node metastasis, increasing tumor clinical stage, and poorer 5-year DFS in patients with breast cancer. TßRII may be a potential prognostic marker for breast cancer.

Association between vacA genotypes and the risk of duodenal ulcer: a meta-analysis.

Epidemiological studies have reported the relationship between vacuolating cytotoxin A (vacA) s-/m- region genotypes and duodenal ulcer (DU), but the results remained inconclusive. We performed the present meta-analysis to investigate a more authentic association between vacA s-/m- region genotypes and DU. Literature search was performed by searching Embase, PubMed and ISI Web of Science databases as well as checking references from identified articles, reviews and the abstracts presented at related scientific societies meetings. The association was assessed by combined odds ratio (OR) with 95% confidence interval (CI). A total of 42 studies were included in our final meta-analysis. The combined ORs (95% CIs) showed that vacA s1 (OR = 2.96, 95% CI = 2.34-3.75), m1 (OR = 1.46, 95% CI = 1.05-2.04) and s1m1 (OR = 1.89, 95% CI = 1.47-2.42) were associated with increased DU risk significantly in the overall studied population. Subgroup analyses by ethnicity showed that vacA s1 increased the risk of DU in Asian countries (OR = 1.92, 95% CI = 1.30-2.83), European countries (OR = 3.58, 95% CI = 2.13-6.03) and Latin American countries (OR = 4.20, 95% CI = 2.21-7.98); vacA m1 increased the risk of DU in Latin American countries (OR = 2.98, 95% CI = 1.59-5.56); vacA s1m1 increased the risk of DU in Asian countries (OR = 2.04, 95% CI = 1.12-3.73) and Latin American countries (OR = 2.05, 95% CI = 1.20-3.48); vacA s2m1 increased the risk of DU in Latin American countries (OR = 2.30, 95% CI = 1.17-4.50). The data suggest that genotype testing of vacA s- and m- region will be useful in screening susceptible individuals for DU development.

No association between IL-1RN VNTR and the risk of duodenal ulcer: a meta-analysis.

The aim of this study was to perform a meta-analysis to investigate a more authentic association between interleukin-1 RN variable number of tandem repeats (IL-1RN VNTR) and duodenal ulcer (DU). Systematic searches of electronic databases Embase, PubMed and Web of Science were performed. Statistical analyses were conducted using software Stata 11.0. The pooled odds ratios (ORs) with 95% confidence intervals (95% CIs) were applied. Publication bias was tested by Begg's funnel plot and Egger's regression test. A total of 16 studies including 2115 cases and 3622 controls were included in our final meta-analysis. There was no evidence of significant association between IL-1RN VNTR and DU (allelic model: OR = 1.04, 95% CI = 0.87-1.26; additive model: OR = 0.85, 95% CI = 0.62-1.16; dominant model: OR = 1.06, 95% CI = 0.92-1.23; and recessive model: OR = 0.83, 95% CI = 0.61-1.12). Significant protective associations were found in additive model (OR = 0.51, 95% CI = 0.31-0.83) and recessive model (OR = 0.45, 95% CI = 0.28-0.73) in Caucasian subgroup. In conclusion, our meta-analysis suggests that there is no evidence of significant association between IL-1RN VNTR and DU with or without Helicobacter pylori infection in overall population, whereas significant association is found by subgroup analyses which showed protective effect of IL-1RN allele 2 against DU risk in Caucasian population.