Expression In Neoplastic Tissues Research Articles

Prostate epithelial cell intrinsic C3 represses MYC-driven tumorigenesis

Abstract The synthesis of complement component C3 within the tumor microenvironment has been implicated as a pivotal modulator in oncogenesis and is emerging as an attractive therapeutic target. Historically, tumor-infiltrating immune cells have been recognized as principal contributors to intra-tumoral C3, with resultant activation fragments primarily facilitating tumor progression via immunosuppression and induction of angiogenesis. Despite the ubiquity of C3 expression in neoplastic tissues, the implications of cancer cell autonomous C3 during oncogenesis remain inadequately characterized. Here we show that loss of steady-state, endogenous C3 expression, C3a generation, and C3a receptor engagement in human prostate epithelial cells (PECs) mark a salient transition towards malignancy. We reveal that tonic intrinsic C3a-C3aR engagement in non-transformed PECs serves to restrain phosphoinositide 3-kinase delta activity, which inhibits the oncogenic MYC cascade and MYC-driven ribosomal biogenesis and nucleolar dynamics to maintain normal cell homeostasis. Further, comprehensive analyses show that C3 transcript and C3 protein levels are widely suppressed across human prostate cancers. Collectively, these findings ascribe a non-traditional, tumor-suppressor function to cell intrinsic C3 and advocate for dissection of the context-specific roles of complement, a strategy that may inform the development of targeted cancer therapies.

MiRNA Expression Profiles in Ovarian Endometriosis and Two Types of Ovarian Cancer-Endometriosis-Associated Ovarian Cancer and High-Grade Ovarian Cancer.

Endometriosis-associated ovarian cancer (EOC) consisting of endometrioid cancer and clear-cell ovarian cancer could be promoted by many factors. miRNAs, which are small, non-coding molecules of RNA, are among them. The aim of this study was to detect miRNAs connected with the malignant transformation of endometriosis. FFPE (formalin-fixed, paraffin-embedded) samples of 135 patients operated on for endometriosis and different types of ovarian cancer (EOC and HGSOC-high-grade serous ovarian cancer) were studied. Healthy ovarian tissue was used as a control group. From the expression panel of 754 miRNAs, 7 were chosen for further tests according to their ROC (receiver operating characteristic) curves: miR-1-3p, miR-125b-1-3p, miR-31-3p, miR-200b-3p, miR-502-5p, miR-503-5p and miR-548d-5p. Furthermore, other potentially important clinical data were analysed, which included age, BMI, Ca-125 concentration, miscarriages and deliveries and concomitant diseases such as hypertension, type 2 diabetes and smoking. Among the miRNAs, miR200b-3p had the lowest expression in neoplastic tissues. miR31-3p had the highest expression in women without any lesions in the ovaries. miR-502-5p and miR-548-5p did not differ between the studied groups. The examined miRNA panel generally distinguished significantly normal ovarian tissue and endometriosis, normal ovarian tissue and cancer, and endometriosis and cancer. The malignant transformation of endometriosis is dependent on different factors. miRNA changes are among them. The studied miRNA panel described well the differences between endometriosis and EOC but had no potential to differentiate types of ovarian cancer according to their origin. Therefore, examination of a broader miRNA panel is needed and might prove itself advantageous in clinical practice.

Investigating the association between neoplasms and MOG antibody-associated disease

IntroductionThe association of myelin oligodendrocyte glycoprotein (MOG) antibody associated disease (MOGAD) and tumors has seldom been reported. We aim to investigate the occurrence of tumors in a cohort of patients with MOGAD and to describe their clinical features, in addition to previously reported cases.MethodsWe retrospectively identified patients with MOGAD (i.e., compatible clinical phenotype and positive MOG antibodies analysed with a live cell-based assay) from 1/1/2015 to 1/1/2023 who had a neoplasm diagnosed within 2 years from MOGAD onset. Furthermore, we performed systematic review of literature to identify previously reported cases. Clinical, paraclinical and oncological findings were collected and reported as median (range) or number (percentage).ResultsTwo of 150 MOGAD patients (1%) had a concomitant neoplasm in our cohort. Fifteen additional cases were retrieved from literature. Median age was 39 (16–73) years-old, 12 patients were female. ADEM (n= 4;23.5%), encephalomyelitis (n= 3;17.6%), and monolateral optic neuritis (n= 2;11.8%) were the most frequent phenotypes. Median number of treatments was 1 (range 1–4), improvement was reported in 14/17 cases (82.4%). Oncological accompaniments were teratoma (n= 4), CNS (n= 3), melanoma (n= 2), lung (n= 2), hematological (n= 2), ovary (n= 1), breast (n= 1), gastrointestinal (n= 1), and thymic (n= 1) neoplasms. Median time from tumor diagnosis to MOGAD onset was 0 (range − 60 to 20) months. MOG expression in neoplastic tissue was reported in 2/4 patients. Median PNS-CARE score was 3 (range 0–7): 11 patients were classified as “non-PNS,” 5 as “possible PNS,” and 1 as “probable PNS.”DiscussionOur study confirms that MOG is a low-risk antibody for paraneoplastic neurological syndromes and that the clinical presentation and oncological accompaniments are extremely variable. Most of these patients were classified as non-PNS, whereas only a minority was diagnosed with possible/probable PNS, frequently in association with ovarian teratoma. These findings support the notion that MOGAD is not a paraneoplastic disease.

Abstract 5457: Prevalence of “low” HER2 expression is frequent in breast cancer but also in cancers of other origin: A tissue microarray study on 131 tumor types

Abstract HER2 is a receptor tyrosine-protein kinase coded by the ERBB2 gene. The HER2 status is routinely assessed to select patients eligible for targeted therapy with anti-HER2 drugs. HER2 positivity was restricted to cancers with a 3+ score at immunohistochemistry (IHC) and/or gene amplification. The successful use of HER2 antibody-drug conjugates in tumors with IHC scores of 1+ (HER2 low) or 0 with incomplete and faint staining in ≤10% of tumor cells (HER2 ultralow) is currently changing the traditional dichotomy of HER2 testing in breast cancer. To determine HER2 expression in neoplastic tissues, a tissue microarray containing one 0.6mm tissue spot each from 7,505 tumor samples from 131 different tumor types and subtypes was analyzed by immunohistochemistry. IHC scoring included 3+, 2+, 1+, and a category “+” (faintly positive in less than 10% of tumor cells; ultralow). The cohort included 310 breast cancers for which the HER2 amplification was also assessed by fluorescence in situ hybridization. Among 555 evaluable breast cancers, HER2 IHC was 3+ in 7.6%, 2+ in 3.2%, 1+ in 14.6%, “+” in 15.9% and 0 in 58.7%. The HER2 amplification rate was in 95.8% of 3+, 61.5% of 2+, 18.2% of 1+, but 0% in “+” and HER2 0 breast cancers. Among 4,912 non-breast cancers, the HER2 status was 3 in 0.6%, 2 in 0.7%, 1 in 3.3%, “+” in 2.3%, and 0 in 93.2%. In these tumors, 3+ positivity was largely restricted to gastric/esophageal adenocarcinoma, urothelial carcinoma, ovarian cancer as well as adenocarcinomas of the lung, colon, and pancreas. A 2+ positivity was mostly seen in tumor entities that had also 3+ cases. A 1+ or “+” HER2 positivity was found in 50 of 147 analyzed non-breast cancer categories. HER2 low and ultralow (1+ or “+”) was most commonly seen in basal cell carcinoma of the skin (52.2%), clear cell carcinoma of the ovary (33.3%), urothelial carcinoma of the renal pelvis (33.3%), gallbladder adenocarcinoma (26.7%), muscle-invasive urothelial carcinoma of the bladder (24.5%), prostatic adenocarcinoma, Gleason 4+4 (23.3%), endometrial serous carcinoma (22.7%), prostatic adenocarcinoma, Gleason 5+5 (19.2%), carcinosarcoma of the ovary (18.8%), renal oncocytoma (17.9%), serous carcinoma of the ovary (17.8%), gastric adenocarcinoma, intestinal type (13.2%), neuroendocrine tumor (NET) of the lung (11.1%), carcinosarcoma of the uterus (11.1%), endometrioid carcinoma of the ovary (11.1%), squamous cell carcinoma of the larynx (10.7%), parathyroid gland adenoma (10%), endometrioid endometrial carcinoma (9.7%), adenocarcinoma of the esophagus (9.5%), cholangiocarcinoma of the liver (9.3%), and pancreatic/ampullary adenocarcinoma (8.6%). While 3+ IHC is limited to only few cancer types, there is a much broader range of tumor entities that can show HER2 low and ultralow expression. HER2 antibody-drug conjugates may therefore be successful drugs in a large variety of different tumor entities. Citation Format: Maximilian Lennartz, Florian Viehweger, David Dum, Ria Uhlig, Andrea Hinsch, Doris Hoeflmayer, Christoph Fraune, Christian Bernreuther, Patrick Lebok, Soeren Weidemann, Guido Sauter, Till Sebastian Clauditz, Frank Jacobsen, Till Krech, Andreas H Marx, Sarah Minner, Ronald Simon, Natalia Gorbokon, Stefan Steurer, Eike Burandt. Prevalence of “low” HER2 expression is frequent in breast cancer but also in cancers of other origin: A tissue microarray study on 131 tumor types. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5457.

Evaluation of TERT mRNA expression using RNAscope®: A potential histopathologic diagnostic and prognostic tool

BackgroundTelomerase reverse transcriptase (TERT) activation has been shown to be an important cancer hallmark; the activation and expression of TERT has been documented in >90% of tumors and TERT activation has been touted as a prognostic marker in many cancers. However, there is currently no simple testing modality to detect TERT mRNA expression in surgical pathology specimens. In this study we aim to evaluate and validate the utility and reliability of the TERT RNAscope® in-situ hybridization (ISH) assay for the detection of TERT mRNA expression in formalin-fixed, paraffin embedded tissue. Methods and MaterialsRNAscope® detection for TERT was performed on a Leica Biosystems BOND III research staining robot using the Hs-TERT-O1 (ACD, 481968) probe. Twenty three samples containing 48 tissue types were assessed. TERT genomic alterations were determined by targeted next generation sequencing (NGS), while TERT mRNA expression was determined by both targeted RNA-sequencing and TERT RNAscope® and the results compared. Manual vs automated TERT expression quantification methodologies were evaluated for the ISH assay. The expression levels in normal vs. neoplastic tissues were also compared. ResultsThe RNAscope® assay showed high TERT expression in neoplastic tissues, while most normal tissues have no or very low expression levels (p-value= 0.0001, AUC: 0.99). In addition, there was good correlation of TERT expression between the RNAscope® assay and RNA-sequencing. For RNAscope® quantification, manual calculation of TERT signal/cell ratio based on a count of 100 cells was superior compared to automated signal detection. ConclusionTERT RNAscope® assay is a simple and reliable tool for the evaluation of TERT mRNA expression. TERT signal/cell ratio based on a count of 100 cells is a reproducible and accurate interpretation approach for evaluation of TERT expression.

Significance of immunohistochemistry biomarkers in prediction of malignant transformation of oral lichen planus: A systematic review.

Background Oral lichen planus (OLP) is a chronic inflammatory disorder with increased risk for malignant transformation. Biomarker validation is a pivotal step in moving newly discovered biomarkers towards clinical implementation. We performed a systematic review of studies on biomarkers related to OLP, wherein biomarkers have been described in at least two independent studies. Our aim was to determine whether any of these biomarkers might be promising in predicting the increased risk of malignant transformation of OLP.Material and Methods We searched the following databases until August 2021: PUBMED, EMBASE, and Web of Science. Due to high heterogeneity, a qualitative rather than quantitative assessment was conducted. Only proteins that consistently showed a significantly high level of expression in neoplastic tissues versus OLP in two or more publications were considered as promising markers.Results Initial database researches identified 1671, of which 24 articles were included in the final analysis. The most frequently reported proteins were p53, Bcl-2 and Ki-67, though there were controversies. PCNA and P21 were the only proteins that showed consistent evidence of clinical usefulness as cancer predictors to be considered as promising markers. Extensive methodological variations in the evaluation of expressions and statistical analyses of the included markers were observed, which hampered comparisons of the results.Conclusions Multiple levels of heterogeneity with a scarcity of high-quality studies were identified. PCNA and P21 were identified as promising predictive markers for evaluating the risk of malignant transformation of OLP, but they require further validation. The focus of future research on validation of predictive biomarkers of OLP should be considered as a high priority because it will accelerate the introduction of newly discovered markers into the clinical setting. Key words:Oral lichen planus, Immunohistochemistry, biomarkers, malignant transformation, PCNA, P21, p53, BCl-2.

Immunoexpression of PTEN, HER2/neu, and Ki-67 in endoscopic gastric carcinoma biopsies; their correlation with histological subtypes and one-year survival.

Gastric carcinoma is a major cause of cancer-related morbidity and mortality worldwide. Gastric neoplasms arise from genetic and epigenetic changes in various genes. Present study evaluates the immunoexpression of PTEN, HER2/neu, and Ki-67 in endoscopic gastric carcinoma biopsies and correlates the expression of these proteins with clinicopathological features. Adequate endoscopic biopsies of 27 cases of gastric carcinoma were evaluated for World Health Organization (WHO) and Lauren's classification subtypes along with HER2/neu, PTEN, and Ki-67 immunoexpression. HER2/neu immunostaining was scored as proposed in the Trastuzumab for gastric cancer (ToGA) trial while PTEN staining and downregulation were assessed using an immunoreactive score. The cut-off for Ki-67 expression was taken as 90th percentile of the values in adjacent non-neoplastic tissue. All statistical analysis was done at 5% level of significance with SPSS v22 statistical software. Tubular adenocarcinoma was the commonest WHO histological subtype and 56% of cases were of intestinal type as per Lauren's classification. 55.6% of cases showed a complete loss of PTEN expression in neoplastic tissue. 17 of the 19 cases with adjacent non-neoplastic tissue showed PTEN downregulation in neoplastic tissue. 81.5% of cases had a high Ki-67 index and HER2/neu overexpression was noted in 36% of cases. All the four cases who died had high Ki-67 proliferation indices; 3 patients had loss of PTEN expression and HER2/neu overexpression. We conclude that these immunomarkers can play important role in the behavior of gastric carcinomas and can be targeted for new therapies.

The role of heat shock proteins in neoplastic processes and the research on their importance in the diagnosis and treatment of cancer.

Heat shock proteins (HSPs) are chaperones with highly conservative primary structure, necessary in the processes of protein folding to the most energetically advantageous conformation and maintaining their stability. HSPs perform a number of important functions in various cellular processes and are capable of modulating pathophysiological conditions at the cellular and systemic levels. An example is the high level of HSP expression in neoplastic tissues, which disrupts the apoptosis of transformed cells and promotes the processes of proliferation, invasion, and metastasis. In addition, an increasing amount of information is appearing about the participation of HSPs in the formation of multidrug resistance.This paper provides a review of the current state of research on the fundamental importance as well as the diagnostic and prognostic role of various classes of HSP in cancer treatment. It presents the prospects for using HSPs as biological markers of disease progression and targets in various cancer treatment strategies. However, the need for additional research is quite high. Only numerous joint efforts of research groups will allow the effective use of HSPs as a tool to combat cancer.

A41 LOSS OF SATB2 EXPRESSION IN COLORECTAL CANCER IS ASSOCIATED WITH DURATION OF INFLAMMATORY BOWEL DISEASE

Abstract Background Patients with inflammatory bowel disease (IBD) are at higher risk for developing colitis-associated colorectal cancer (CAC). Clinical and endoscopic features are used to stratify the risk of CAC, but new biomarkers are necessary to improve this stratification. Recent studies have shown that loss of expression of special AT-rich sequence binding protein 2 (SATB2) is frequent in CAC compared to sporadic colorectal cancer and this SATB2 status is found in pre-cancerous dysplastic lesions as well. However, the relationship of known clinical risk factors for CAC and loss of SATB2 has not been explored. Aims To assess the association of loss of SATB2 expression in CAC with clinical characteristics of IBD. Methods Patients with a known diagnosis of ileocolonic or colonic Crohn’s disease (CD), ulcerative colitis (UC), or IBD unclassified (IBDU) who underwent colectomy between October 2010 and December 2017 for CAC were included. SATB2 expression in neoplastic tissue was evaluated using immunohistochemistry (IHC), where less than 5% of tumor cells showing staining was considered loss of SATB2. Tumor grade, P53 and mismatch repair (MMR) status were assessed as well. Available clinical data such as sex, smoking status, IBD diagnosis (CD, UC or IBDU), age at IBD diagnosis, duration of IBD, extent of colitis and previous medications were collected. We used a generalized linear model to assess the association between these biomarkers and clinical data. Results A total of 58 patients with mean age at CAC diagnosis of 50.3 ±13 years, 27 (46%) females were analyzed. Mean IBD duration was 17.6 ±10 years and 22 (37.9%), 34 (58.6%) and 2 (3.4%) were CD, UC and IBDU, respectively. Thirty-two (55.2%) CACs had loss of SATB2 expression. There was no association between age at CAC diagnosis or grade of the tumor and loss of SATB2. However, longer duration of IBD (21.2 ± 9 years vs 13.7 ± 9 years, p = 0.01) was significantly associated with loss of SATB2. There was no association between SATB2 status and other explored clinical or endoscopic variables. Tumors with P53 mutation were associated with a younger age at diagnosis of CAC (47.2 ±13 vs 55.0 ±12 years, p = 0.03), but no other associations of this marker or MMR with clinical or endoscopic variables of IBD were found. Conclusions Loss of SATB2 expression is significantly associated with IBD duration, a well-known risk factor for CAC. This association with duration of IBD could denote an effect of longer chronic inflammation on SATB2 status. Given the previously reported association of loss of expression of SATB2 with pre-cancerous lesions in IBD patients, this could be a potential biomarker for risk of CAC. Funding Agencies National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Identification of human miR-1839-5p by small RNA-seq, a miRNA enriched in neoplastic tissues.

MicroRNAs (miRNAs) modulate gene expression through destabilization or translational inhibition of cytoplasmic transcripts or by transcriptional regulation through binding to genomic DNA. Although miRNAs are globally down-regulated in cancer, some are overexpressed in neoplastic tissues, playing key roles in tumorigenesis (oncomiRs), sometimes behaving as effective cancer markers. Using total RNA from human uterus adenocarcinoma and non-neoplastic uterus, we conducted a small RNA-sequencing experiment followed by prediction of novel miRNAs using MirDeep* software. Synteny analysis and whole genome alignments were performed using BLAST. We also evaluated expression by a reverse transcriptase-polymerase chain reaction (RT-PCR) in normal tissues of the FSD2 gene, which spans the human miR-1839-5p gene in the opposite direction. MirDeep* analysis predicted a miRNA not previously annotated in databases, identical to and likely the orthologue of mouse miR-1839-5p. Whole-genome local alignments of this miRNA revealed a single perfect hit that is indeed syntenic to mouse miR-1839-5p. Alignments with other mammalian orthologues showed considerable conservation. We validated the prediction via a stem-loop RT-PCR assay, also employed to screen RNA samples from several additional normal and cancer tissues, showing increased expression in neoplastic tissues compared to their respective non neoplastic counterparts. Human heart tissue expresses both miR-1839-5p and FSD2. Human tissues express an orthologue of mouse miR-1839-5p and, given its expression pattern, we suggest that this miRNA could be explored as a potential oncomiR or cancer marker. Also, according to the genomic organization of miR-1839-5p and FSD2, perfect complementarity exists between the two elements, making possible miRNA-directed cleavage in human cardiac tissue.

PanCD44 Immunohistochemical Evaluation in Prostatectomies from Patients with Adenocarcinoma.

Introduction CD44 has been proposed as a prognostic marker and a stem cell marker but studies in patients with prostate cancer have yielded inconsistent results. Patients and Methods Patients submitted to radical prostatectomy between 2008 and 2013 at a university hospital were followed with biannual serum PSA tests to determine the biochemical recurrence (BR). Archived paraffin blocks with neoplastic and nonneoplastic tissue were evaluated immunohistochemically for a panCD44 and MYC. Results Sixty-nine patients completed follow-up and were included. CD44 positivity was observed in inflammatory cells (42%), nonneoplastic epithelium (39.7%), and neoplastic tissue (12.3%). In nonneoplastic tissues staining was observed in basal and luminal cells with the morphology of terminally differentiated cells. In neoplastic tissues, CD44 negativity was correlated with higher Gleason scores (Rho = −0.204; p = 0.042) and higher preoperative serum PSA levels when evaluated continuously (p = 0.029). CD44 expression was not associated with tumor stage (p = 0.668), surgical margin status (p = 0.471), or BR (p = 0.346), nor was there any association between CD44 and MYC expression in neoplastic tissue (p = 1.0). Conclusion In the bulk of cells, the minority of cancer stem cells would not be detected by immunohistochemistry using panCD44. As a prognostic marker, its expression was weakly correlated with Gleason score and preoperative PSA level, but not with surgical margin status, tumor stage, or BR.

Investigation of E2, E5, and E6 gene expression and DNA in situ fragmentation findings associated with progressive and regressive changes in benign neoplastic cutaneous lesions arising naturally from bovine papillomavirus-1 infection

This study investigated the progressive and regressive phases of bovine papillomavirus (BPV)-1-induced papilloma and fibropapilloma in terms of the distribution of viral antigenicity; E2, E5, and E6 gene activity and expression; and apoptosis (evaluated using DNA in situ fragmentation). All samples from 74 bovine cases of cutaneous lesions with suspected neoplastic changes collected from different skin areas were evaluated. The lesions were diagnosed as papilloma or fibropapilloma using routine hematoxylin–eosin and Mallory’s trichrome staining protocols. Feulgen reactions suggested a possible viral entity, and BPV-1 antigenicity was immunohistochemically observed in 22 cases. E gene expression in neoplastic tissues was evaluated using chromogenic in situ hybridization and reverse-transcription polymerase chain reaction, and the TUNEL method was used to evaluate DNA in situ fragmentation. Differences between progressive and regressive phases in these lesions were analyzed. Ultimately, the number of cases in the progressive phase (18) and regressive phase (4) were determined. Although E2 and E5 gene expression was observed in both phases, E6 gene distribution differed from the other E genes distribution in the progressive phase. E5 gene expression appeared stronger in oncogenic fibrocytes and fibroblasts, whereas E2 and E6 gene expression was weaker in epidermal cells and cells in the regressive phase. Apoptosis, considered the best indicator of neoplastic regression, was found to be associated with the regressive phase but was observed insufficiently in epidermal and dermal samples of the progressive-phase cases. In conclusion, this work provides significant insights on the molecular and immunopathological features of BPV-1.

Involvement of Cytochrome P450 in Reactive Oxygen Species Formation and Cancer.

This review examines the involvement of cytochrome P450 (CYP) enzymes in the formation of reactive oxygen species in biological systems and discusses the possible involvement of reactive oxygen species and CYP enzymes in cancer. Reactive oxygen species are formed in biological systems as byproducts of the reduction of molecular oxygen and include the superoxide radical anion (∙O2-), hydrogen peroxide (H2O2), hydroxyl radical (∙OH), hydroperoxyl radical (HOO∙), singlet oxygen ((1)O2), and peroxyl radical (ROO∙). Two endogenous sources of reactive oxygen species are the mammalian CYP-dependent microsomal electron transport system and the mitochondrial electron transport chain. CYP enzymes catalyze the oxygenation of an organic substrate and the simultaneous reduction of molecular oxygen. If the transfer of oxygen to a substrate is not tightly controlled, uncoupling occurs and leads to the formation of reactive oxygen species. Reactive oxygen species are capable of causing oxidative damage to cellular membranes and macromolecules that can lead to the development of human diseases such as cancer. In normal cells, intracellular levels of reactive oxygen species are maintained in balance with intracellular biochemical antioxidants to prevent cellular damage. Oxidative stress occurs when this critical balance is disrupted. Topics covered in this review include the role of reactive oxygen species in intracellular cell signaling and the relationship between CYP enzymes and cancer. Outlines of CYP expression in neoplastic tissues, CYP enzyme polymorphism and cancer risk, CYP enzymes in cancer therapy and the metabolic activation of chemical procarcinogens by CYP enzymes are also provided.

MiRNA-21, miRNA-10b, and miRNA-34a Expression in Canine Mammary Gland Neoplasms

Abstract The expression of miRNA-21, miRNA-10b, and miRNA-34a in malignant and benign tumours and non-neoplastic lesions in canine mammary gland, using real-time PCR with TaqMan probes was determined. The expression in normal tissues was compared to neoplastic and non-neoplastic lesions using one-way ANOVA test. Significant changes in miRNA expression in neoplastic tissues, as compared to normal ones, were demonstrated. In all neoplastic tissues, the miRNA-21 expression increased while in non-neoplastic lesions slightly decreased in comparison to normal ones. MiRNA-10b expression in malignant and benign tumours increased in comparison to normal tissues and non-neoplastic lesions. MiRNA-34a expression profile in neoplastic and non-neoplastic tissues differed from other examined miRNAs (miRNA-21 and miRNA-10b). In all samples miRNA-34a expression level decreased in comparison to normal tissues.

PRL-3 and E-cadherin show mutual interactions and participate in lymph node metastasis formation in gastric cancer

E-cadherin, a transmembrane adhesion molecule, and phosphatase of regenerating liver 3 (PRL-3) protein, a member of the family of tyrosine phosphatases, seem to be responsible for cancer cell migration. Therefore, the study objective was to determine a correlation between PRL-3 and E-cadherin, to assess their expression in neoplastic tissue and normal mucosa of the stomach, to analyze their effect on cancer advancement, and to evaluate their potential as prognostic markers in gastric cancer. The expressions of PRL-3 and E-cadherin were assessed immunohistochemically in 71 patients with gastric cancer. Positive expression of PRL-3 was observed in 42.2 % of gastric cancer cases, whereas E-cadherin expression was abnormal in 38 % of cases. The study revealed that the positive PRL-3 expression and abnormal E-cadherin expression were associated with mucinous gastric carcinoma and lymph node involvement. The former was also related to the infiltrating type of tumor and abnormal E-cadherin expression. The expression of PRL-3, but not of E-cadherin, was associated with shorter survival of patients. PRL-3 and E-cadherin exhibit interactions in gastric cancer and are involved in the formation of lymph node metastases. The PRL-3 protein can be an independent predictive factor of overall survival in gastric cancer patients.

FOXE1 and SYNE1 Genes Hypermethylation Panel as Promising Biomarker in Colitis-associated Colorectal Neoplasia

Colitis-associated colorectal cancer affects individuals with inflammatory bowel disease (IBD) more often and earlier than cancer in the general population. Colonoscopy provides the surveillance gold standard. Changes to the surveillance intervals depending on endoscopic activity have been made, given data demonstrating that this is an important predictor of future dysplasia or cancer, but adjuvant, noninvasive clinical tools are still warranted to improve surveillance outcomes and to assist in management and interpretation of dysplasia. Methylation markers may be able to do this. SYNE1, FOXE1, NDRG4, and PHACTR3 genes were screened using methylation-specific PCR that permit the methylation status of the genes to be determined directly on biopsies. Ninety-three patients with long-standing IBD undergoing a cancer surveillance program, and 30 healthy controls were studied. These included colorectal adenocarcinomas on a background of IBD of various stages (n = 25), IBD-associated dysplastic lesions (n = 29), adenomas arising on a background of ulcerative colitis (n = 8), samples from patients with no evidence of dysplasia or cancer but long-standing IBD (n = 31), and symptomatic patients found to have normal colonoscopy (controls) (n = 30). Gene promotor hypermethylation of SYNE1 and FOXE1 genes varied significantly between the groups and was increasingly likely with increased disease severity. Neither occurred in controls, whereas promotor hypermethylation was detected in biopsies of 60% of patients with colitis-associated colorectal cancer for FOXE1 and 80% for SYNE1. Promotor hypermethylation of either gene was highly significantly different between the groups overall. FOXE1 and SYNE1 hypermethylation markers demonstrated significantly increased expression in neoplastic tissue. Promoter methylation analysis of these genes might be a useful marker of neoplasia in long-standing IBD.

PTU-064 Identification of Syne1 and Foxe1 Hypermethylation to improve Diagnosis and Management of Colerectal Neoplasia in Inflammatory Bowel Disease

IntroductionColitis-associated colorectal cancer (CAC) affects individuals with inflammatory bowel disease (IBD) more often and younger than cancer in the general population. Colonoscopy provides the surveillance gold standard. Changes to surveillance...

Su1257 Identification of Syne1 and Foxe1 Hypermethylation to Improve Diagnosis and Management of Colerectal Neoplasia in Inflammatory Bowel Disease

Introduction Colitis-associated colorectal cancer (CAC) affects individuals with inflammatory bowel disease (IBD) more often and younger than cancer in the general population. Colonoscopy provides the surveillance gold standard. Changes to surveillance intervals have been made given data demonstrating that endoscopic appearance is an important predictor of future dysplasia or cancer, but adjuvant, non-invasive clinical tools are still warranted to improve surveillance outcomes and to assist in management and interpretation of dysplasia. Methylation markers may be able to do this. Material and methods Methods using reexpression profiles of colon cancer cell lines, candidate genes were identified; promising markers were tested on tissue using the Base5 methylation-profiling platform. Promoter sequences were linked with gene expression to identify epigenetically silenced genes. Marker candidates were screened using methylation specific PCR assays to assess the methylation status of 2 gene promoters (FOXE1, SYNE1) in biopsies from 93 longstanding IBD patients and 30 healthy controls. Samples included colitis-associated colorectal adenocarcinomas (n = 25); IBD-associated dysplastic lesions (n = 29); adenomas arising on a background of UC (n = 8); samples from IBD patients with no neoplasia (n = 31) and healthy controls (n = 30). Results The presence of the 2 genes significantly varied between the groups. Both were increasing likely with increased disease severity. Neither occurred in controls, whilst 60% of CAC patients had FOXE1, and 80% of CAC patients had SYNE1. Conclusion FOXE1- SYNE1 methylation markers panel demonstrated significantly increased expression in neoplastic tissue. Syne1 was highly represented in CAC. Methylation of these promoter genes might be considered a potentially useful pathology marker of neoplasia in longstanding inflammatory bowel disease. Disclosure of Interest None Declared

Su1261 Expression of Interleukins 22 and 33, Matrix Metalloproteinases 9 and 13, Mast Cell Markers and Hypoxia-Inducible Factor 1α in Crohn's Disease Associated Fistulae

Background and aim : Colitis-associated colorectal cancer (CAC) affects individuals with inflammatory bowel disease (IBD) more often and younger than cancer in the general population. Colonoscopy provides the surveillance gold standard. Changes to surveillance intervals have been made given data demonstrating that endoscopic appearance is an important predictor of future dysplasia or cancer, but adjuvant, non-invasive clinical tools are still warranted to improve surveillance outcomes and to assist in management and interpretation of dysplasia. Methylation markers may be able to do this. Material and methods : Methods: using reexpression profiles of colon cancer cell lines, candidate genes were identified; promising markers were tested on tissue using the Base5 methylation-profiling platform. Promoter sequences were linked with gene expression to identify epigenetically silenced genes.Marker candidates were screened using methylation specific PCR assays to assess the methylation status of 2 gene promoters (FOXE1, SYNE1) in biopsies from 93 longstanding IBD patients and 30 healthy controls. Samples included colitis-associated colorectal adenocarcinomas (n= 25); IBD-associated dysplastic lesions (n=29); adenomas arising on a background of UC (n= 8); samples from IBD patients with no neoplasia (n=31) and healthy controls (n=30). Results : The presence of the 2 genes significantly varied between the groups. Both were increasing likely with increased disease severity. Neither occurred in controls, whilst 60% of CAC patients had FOXE1, and 80% of CAC patients had SYNE1. Conclusions : FOXE1SYNE1 methylation markers panel demonstrated significantly increased expression in neoplastic tissue. Syne1 was highly represented in CAC. Methylation of these promoter genes might be considered a potentially useful pathology marker of neoplasia in longstanding inflammatory bowel disease.

Su1258 The Role of the Leucine-Rich Repeat Kinase 2 (LRRK2) in Development and Severity of Inflammatory Bowel Disease (IBD)

Background and aim : Colitis-associated colorectal cancer (CAC) affects individuals with inflammatory bowel disease (IBD) more often and younger than cancer in the general population. Colonoscopy provides the surveillance gold standard. Changes to surveillance intervals have been made given data demonstrating that endoscopic appearance is an important predictor of future dysplasia or cancer, but adjuvant, non-invasive clinical tools are still warranted to improve surveillance outcomes and to assist in management and interpretation of dysplasia. Methylation markers may be able to do this. Material and methods : Methods: using reexpression profiles of colon cancer cell lines, candidate genes were identified; promising markers were tested on tissue using the Base5 methylation-profiling platform. Promoter sequences were linked with gene expression to identify epigenetically silenced genes.Marker candidates were screened using methylation specific PCR assays to assess the methylation status of 2 gene promoters (FOXE1, SYNE1) in biopsies from 93 longstanding IBD patients and 30 healthy controls. Samples included colitis-associated colorectal adenocarcinomas (n= 25); IBD-associated dysplastic lesions (n=29); adenomas arising on a background of UC (n= 8); samples from IBD patients with no neoplasia (n=31) and healthy controls (n=30). Results : The presence of the 2 genes significantly varied between the groups. Both were increasing likely with increased disease severity. Neither occurred in controls, whilst 60% of CAC patients had FOXE1, and 80% of CAC patients had SYNE1. Conclusions : FOXE1SYNE1 methylation markers panel demonstrated significantly increased expression in neoplastic tissue. Syne1 was highly represented in CAC. Methylation of these promoter genes might be considered a potentially useful pathology marker of neoplasia in longstanding inflammatory bowel disease.