Maria Gazouli

Sequence variants in IL10, ARPC2 and multiple other loci contribute to ulcerative colitis susceptibility

Inflammatory bowel disease (IBD) typically manifests as either ulcerative colitis (UC) or Crohns disease (CD). Systematic identification of susceptibility genes for IBD has thus far focused mainly on CD, and little is known about the genetic architecture of UC. Here we report a genome-wide association study with 440,794 SNPs genotyped in 1,167 individuals with UC and 777 healthy controls. Twenty of the most significantly associated SNPs were tested for replication in three independent European case-control panels comprising a total of 1,855 individuals with UC and 3,091 controls. Among the four consistently replicated markers, SNP rs3024505 immediately flanking the IL10 (interleukin 10) gene on chromosome 1q32.1 showed the most significant association in the combined verification samples (P = 1.35 × 10−12; OR = 1.46 (1.31–1.62)). The other markers were located in ARPC2 and in the HLA-BTNL2 region. Association between rs3024505 and CD (1,848 cases, 1,804 controls) was weak (P = 0.013; OR = 1.17 (1.01–1.34)). IL10 is an immunosuppressive cytokine that has long been proposed to influence IBD pathophysiology. Our findings strongly suggest that defective IL10 function is central to the pathogenesis of the UC subtype of IBD.

Expression of microRNAs, miR-21, miR-31, miR-122, miR-145, miR-146a, miR-200c, miR-221, miR-222, and miR-223 in patients with hepatocellular carcinoma or intrahepatic cholangiocarcinoma and its prognostic significance.

MicroRNAs are a class of non‐coding molecules found to regulate a variety of cellular functions in health and disease. Dysregulation of microRNAs is involved in liver disease, especially hepatocarcinogenesis. Since primary hepatic malignancies are typically characterized by late diagnosis, frequent recurrence, and poor response to adjuvant therapy, there is a need for the discovery of novel biomarkers in order to achieve earlier diagnosis, predict tumor aggressiveness and response to adjuvant therapy. The purpose of this study is to evaluate the expression of certain microRNAs (miR‐21, ‐31, ‐122, ‐145, ‐146a, ‐ 200c, ‐221, ‐222 and ‐223) in patients with hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC), as well as to assess their prognostic significance. Micro‐RNA expression was assessed by reverse transcription and real‐time PCR (RT‐PCR). Clinicopathological data and survival rates were retrieved and analyzed. According to our results, miR‐21, miR‐31, miR‐122, miR‐221, miR‐222 were significantly up‐regulated in HCC tissues, whereas miR‐145, miR‐146a, miR‐200c, and miR‐223 were found to be down‐regulated. Concerning ICC samples, miR‐21, miR‐31, and miR‐223 were found to be over‐expressed, whereas miR‐122, miR‐145, miR‐200c, miR‐221, and miR‐222 were down‐regulated. Additionally, expression of miR‐21, miR‐31, miR‐122, and miR‐221 in HCC correlated with cirrhosis, while miR‐21 and miR‐221 associated with tumor stage and poor prognosis. In ICC tissues, miR‐21, miR‐31, and miR‐223 were found to be over‐expressed, but no correlation with clinicopathological features was found.

Genome-wide association study for ulcerative colitis identifies risk loci at 7q22 and 22q13 (IL17REL)

We performed a genome-wide association analysis of 1,897,764 SNPs in 1,043 German ulcerative colitis (UC) cases and 1,703 controls. We discovered new associations at chromosome 7q22 (rs7809799) and at chromosome 22q13 in IL17REL (rs5771069) and confirmed these associations in six replication panels (2,539 UC cases and 5,428 controls) from different regions of Europe (overall study sample Prs7809799 = 8.81 × 10−11 and Prs5771069 = 4.21 × 10−8, respectively).

Circulating MicroRNA in inflammatory bowel disease

BACKGROUND MicroRNAs (miRNAs) consist of a group of small noncoding RNAs that partially regulate gene expression. We investigated the expression patterns of commonly deregulated miRNAs in Crohns disease (CD) and ulcerative colitis (UC) in peripheral blood samples of inflammatory bowel disease patients. PATIENTS AND METHODS This study consisted of 128 CD and 88 UC patients, as well as 162 healthy controls. The expression patterns of the miRNA species were quantitatively assayed using reverse transcription and real-time RT-PCR. Stem-loop complementary DNAs (cDNAs) were synthesized using looped reverse transcription primers specific for each miRNA. RESULTS MiR-16, miR-23a, miR-29a, miR-106a, miR-107, miR-126, miR-191, miR-199a-5p, miR-200c, miR-362-3p and miR-532-3p were expressed at significantly higher levels in the blood from patients with CD compared with the healthy controls. No significant differences were observed when the CD patients were classified according to disease location and phenotype. In the UC cases three miRNAs (miR-16, miR-21, miR-28-5p, miR-151-5p, miR-155 and miR-199a-5p) were significantly increased compared to healthy controls. miR-155 was the most highly expressed of the UC-associated miRNA in blood samples. CONCLUSIONS Our results suggest that several miRNAs could distinguish CD from UC by real-time PCR. This further highlights the putative role of miRNAs as contributors to IBD pathogenesis. They may help develop new non-invasive biomarkers to distinguish UC and CD.

Expression of microRNAs in patients with pancreatic cancer and its prognostic significance.

Objectives Investigation of expression profile of well-established microRNAs in pancreatic adenocarcinoma, and its correlation with clinicopathological factors. Methods Eighty-eight samples of ductal pancreatic adenocarcinoma and 98 control samples were analyzed by real-time polymerase chain reaction for miR-21, miR-31, miR-122, miR-145, miR-146a, miR-155, miR-210, and miR-222 expressions. The results were normalized and then statistically analyzed using nonparametric statistical tests. Results According to our results, miR-21, miR-155, miR-210, miR-221, and miR-222, were overexpressed in diseased tissues than in the control samples, whereas miR-31, miR-122, miR-145, and miR-146a were underexpressed. Additionally, the expressions of miR-21 and miR-155 were associated with tumor stage and poor prognosis. Conclusions The tumorigenic role of miR-21 and miR-155 was confirmed, whereas down-regulation of miR-31, miR-145, and miR-146a, in dispute with current literature, renders necessary the revision of use of microRNAs as biological markers.

COMMON POLYMORPHISMS IN THE VASCULAR ENDOTHELIAL GROWTH FACTOR GENE AND COLORECTAL CANCER DEVELOPMENT, PROGNOSIS, AND SURVIVAL

Angiogenesis plays an important role in growth, progression, and metastasis of tumors. The most important regulator of angiogenesis is vascular endothelial growth factor (VEGF). VEGF expression has been associated with advance stage and poor survival of several cancers. In the present study we evaluated the association of functional polymorphisms in the VEGF gene with colorectal cancer development, prognosis, and survival. Three hundred twelve consecutive patients with surgically treated colorectal adenocarcinoma were enrolled in the present study. The genomic DNA was extracted from paraffin‐embedded tissue and five VEGF (−2578C>A, −1154G>A, −634G>C, −460T>C, and +936C>T) gene polymorphisms were determined using a polymerase chain reaction‐restriction fragment length polymorphism assay. VEGF −2578C>A, −1154G>A, −634G>C, −460T>C, and +936C>T genotype and allele frequencies were similar among patients and controls. There was a trend showing carriers of the −2578A and +936T alleles more frequent among patients with CRC, but these differences did not reach statistical significance. Furthermore, no correlation was found between all these variants and tumor characteristics like size, histological grading, positive regional lymph node metastases or tumor stage. However, the −2578AA, −634CC, and +936TT genotypes found to be related with a significantly lower overall survival in our study. In conclusion, VEGF gene polymorphisms were found to be an independent prognostic marker for Greek CRC patients.

Detection of Mycobacterium avium subsp. paratuberculosis in Retail Cheeses from Greece and the Czech Republic

ABSTRACT We investigated the presence of Mycobacterium avium subsp. paratuberculosis in retail cheeses from Greece and the Czech Republic. We found that 31.7% and 3.6% of our samples reacted positive by PCR and culture, respectively. Consumption of these cheeses is likely to result in human exposure to M. avium subsp. paratuberculosis, albeit at a low level for viable cells.

Common variation at 2p13.3, 3q29, 7p13 and 17q25.1 associated with susceptibility to pancreatic cancer.

Pancreatic cancer is the fourth leading cause of cancer death in the developed world. Both inherited high-penetrance mutations in BRCA2 (ref. 2), ATM, PALB2 (ref. 4), BRCA1 (ref. 5), STK11 (ref. 6), CDKN2A and mismatch-repair genes and low-penetrance loci are associated with increased risk. To identify new risk loci, we performed a genome-wide association study on 9,925 pancreatic cancer cases and 11,569 controls, including 4,164 newly genotyped cases and 3,792 controls in 9 studies from North America, Central Europe and Australia. We identified three newly associated regions: 17q25.1 (LINC00673, rs11655237, odds ratio (OR) = 1.26, 95% confidence interval (CI) = 1.19–1.34, P = 1.42 × 10−14), 7p13 (SUGCT, rs17688601, OR = 0.88, 95% CI = 0.84–0.92, P = 1.41 × 10−8) and 3q29 (TP63, rs9854771, OR = 0.89, 95% CI = 0.85–0.93, P = 2.35 × 10−8). We detected significant association at 2p13.3 (ETAA1, rs1486134, OR = 1.14, 95% CI = 1.09–1.19, P = 3.36 × 10−9), a region with previous suggestive evidence in Han Chinese. We replicated previously reported associations at 9q34.2 (ABO), 13q22.1 (KLF5), 5p15.33 (TERT and CLPTM1), 13q12.2 (PDX1), 1q32.1 (NR5A2), 7q32.3 (LINC-PINT), 16q23.1 (BCAR1) and 22q12.1 (ZNRF3). Our study identifies new loci associated with pancreatic cancer risk.

Survivin -31G/C promoter polymorphism and sporadic colorectal cancer

IntroductionSurvivin is an apoptotic inhibitor, plays an important role in cell cycle regulation, and may be involved in the development and progression of cancer. A common polymorphism at the survivin gene promoter (-31 G/C) has been shown to influence survivin expression and the risk for cancer.AimThe aim of the present study was to investigate whether this polymorphism could be involved in the sporadic colorectal cancer (CRC) development, prognosis, and survival.Materials and methodsThe -31G/C polymorphism of survivin promoter was analyzed by polymerase chain reaction (PCR) restriction fragment length polymorphism method in biopsies from 312 patients with sporadic CRC and 362 healthy individuals. Survivin messenger RNA (mRNA) expression in CRC tissues was detected by quantitative reverse transcriptase PCR.Results and discussionThe genotype frequencies for -31GG, -31GC, and -31CC were 21.79%, 41.99%, and 36.22% in CRC patients and 33.98%, 45.03%, and 20.99% in healthy subjects, respectively. The frequencies of the survivin -31C allele and CC genotype were significantly higher in CRC patients than in healthy subjects (p < 0.0001). Homozygotes for the -31CC survivin genotype, expressed 1.6-fold higher mRNA levels of survivin compared to cases with the -31GG and -31GC genotypes.ConclusionThe -31CC genotype of survivin promoter is associated with CRC and may be a risk factor for CRC.

Assessment of Mycobacterial, Propionibacterial, and Human Herpesvirus 8 DNA in Tissues of Greek Patients with Sarcoidosis

ABSTRACT The causes of sarcoidosis are unknown. In this study, we report the presence of Mycobacterium tuberculosis complex and Propionibacterium granulosum DNA in a significant proportion of Greek patients with sarcoidosis. Human herpesvirus 8 DNA was not detected in sarcoid tissues from Greek patients. Our findings are discussed.