Identification of novel biomarkers with potential for diagnosis and prognosis of gastric cancer: a bioinformatics approach

INTRODUCTION: Gastric cancer (GC) is the fifth most diagnosed neoplasia and the third leading cause of cancer-related deaths. A substantial number of patients exhibit an advanced GC stage once diagnosed. Therefore, the search for biomarkers contributes to the improvement and development of therapies. OBJECTIVE: This study aimed to identify potential GC biomarkers making use of in silico tools. METHODS: Gastric tissue microarray data available in Gene Expression Omnibus and The Cancer Genome Atlas Program was extracted. We applied statistical tests in the search for differentially expressed genes between tumoral and non-tumoral adjacent tissue samples. The selected genes were submitted to an in-house tool for analyses of functional enrichment, survival rate, histological and molecular classifications, and clinical follow-up data. A decision tree analysis was performed to evaluate the predictive power of the potential biomarkers. RESULTS: In total, 39 differentially expressed genes were found, mostly involved in extracellular structure organization, extracellular matrix organization, and angiogenesis. The genes SLC7A8, LY6E, and SIDT2 showed potential as diagnostic biomarkers considering the differential expression results coupled with the high predictive power of the decision tree models. Moreover, GC samples showed lower SLC7A8 and SIDT2 expression, whereas LY6E was higher. SIDT2 demonstrated a potential prognostic role for the diffuse type of GC, given the higher patient survival rate for lower gene expression. CONCLUSION: Our study outlines novel biomarkers for GC that may have a key role in tumor progression. Nevertheless, complementary in vitro analyses are still needed to further support their potential.

Expression and prognostic significance of sodium-coupled neutral amino acid transporter 1 in esophageal squamous cell carcinoma / 第二军医大学学报

Objective To investigate the expression of sodium-coupled neutral amino acid transporter 1 (SNAT1) in esophageal squamous cell carcinoma (ESCC) tissues, and to evaluate its prognostic value in patients with ESCC. Methods The tissue microarray including 183 ESCC tissues and their corresponding adjacent tissues was subjected to immunohistochemistry detection and Western blotting analysis of SNAT1 expression, and their correlation with the clinicopatho logical parameters and overall survival time was analyzed. Results SNAT1 was highly expressed in ESCC tissues, with the positive rate being 45. 4% (83/183); we also noticed that t was not expressed in normal squamous epithelium tissues. Our analysis results indicated that overexpression of SNAT1 was significantly correlated with tumor size (P=0.023), lymph node metastasis (P=0.007) and tumor stage (P=0.003). The Kaplan-Meier analysis showed that patients with overexpression of SNAT1 had significantly worse outcome than those with negative SNAT1 expression (P=0.001). Cox regression analysis revealed that over expression of SNAT1 was an independent factor for prognostic of patients with ESCC (P=0.004). Conclusion The expression of SNAT1 is abnormally increased in ESCC tissue, indicating that SNAT1 expression may serve as an important biomarker for prognosis evaluation in patients with ESCC.

Gastric biomarker study using proteomic method

Biomarker is defined as biological variables that correlate with biologic outcome. This review will discuss investigations into gastric cancer (GC) biomarkers by proteomic analysis. Proteomic analysis consists of 3 steps. The first step is the digestion and separation process using 2-dimensional electrophoresis gel or liquid chromatography. The second step is mass analysis using mass spectrometry. The third step is protein identification using databases. Clinical validation of proteins identified can help estimate expressions of cancer tissue and cancer cell line using Western blot and immunohistochemistry. Researchers can validate the association between protein expression and clinical data (tumor stage, cell type, survival, and recurrence), which helps identify the possibility of biomarkers for GC. After clinical validation, the next step is functional analysis in vitro and in vivo. This step is commonly performed by knock-in and knock-out studies on the proliferation, migration, and invasion using the cancer cell line. Animal studies also provide indirect evidence for the role of the proteins in tumor growth and metastasis in vivo. In conclusion, the proteomic analysis is one of the useful methods for detecting biomarkers for GC. Multidisciplinary approaches to protein, DNA, RNA, and epigenetics are crucial to the investigation for molecular biomarkers for GC.

Prognostic Implication of Semi-quantitative Immunohistochemical Assessment of CD20 Expression in Diffuse Large B-Cell Lymphoma

BACKGROUND: Immunohistochemical demonstration of CD20 in diffuse large B-cell lymphoma (DLBCL) is prerequisite not only for the diagnosis but also for assigning patients to rituximab-containing chemotherapy. However, little is known about the impact of abundance of CD20 expression assessed by immunohistochemistry on the clinical outcome of DLBCL. We performed a semi-quantitative immunohistochemical analysis of CD20 expression in DLBCL to examine the prognostic implication of the level of CD20 expression. METHODS: Pre-treatment diagnostic tissue samples from 48 DLBCL patients who were treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) regimen were represented in a tissue microarray and immunostained for CD20. The relative abundance of CD20 expression was semi-quantitatively scored using a web-based ImmunoMembrane plug-in. Receiver operating characteristic curve analysis was used to determine a prognostically relevant cut-off score in order to dichotomize the patients into CD20-high versus CD20-low groups. RESULTS: The levels of CD20 expression were heterogeneous among the patients, with a wide and linear distribution of scores. Patients in CD20-low group showed significantly poor clinical outcome. CONCLUSIONS: The levels of CD20 expression in DLBCL are heterogeneous among the patients with DLBCL. A subgroup of the patients with CD20 expression levels below the cut-off score showed poor clinical outcome.

High Notch1 Expression Correlates with Tumor Stage and Size in Clear Cell Renal Cell Carcinoma

PURPOSE: Although the influence of Notch signaling on several types of malignancies has been studied, the role of Notch signaling in clear cell renal cell carcinoma (ccRCC) remains unclear. In this study, we evaluated the levels of Notch1 and Jagged1 and their significance in ccRCC. MATERIALS AND METHODS: Tumor tissue and matched normal adjacent kidney tissue from 49 ccRCC cases were obtained. The expression of Notch1 and Jagged1 was analyzed using real-time polymerase chain reaction (PCR) and Western blotting. Tissue samples were divided into several groups according to clinicopathological features, and the relative expression of Notch1 and Jagged1 was assessed. RESULTS: Real-time PCR revealed increased Notch1 expression in tumor tissues compared with that in adjacent normal tissues (p=0.044). Based on the pathological stage, a significant difference in Notch1 expression was observed between tumor and normal kidney tissues in pT2 and pT3 ccRCC (pT2, p=0.041; pT3, p=0.001). Notch1 expression in ccRCC relative to that in normal tissue was higher in later-stage ccRCC and larger ccRCC. Notch1 expression showed significant positive correlation with the maximal diameter of the primary renal tumor (mRNA, p<0.001; protein, p=0.001). High Notch1 expression was associated with recurrence and disease-specific death, although the difference was not significant. Jagged1 level was not significantly correlated with any of the factors examined. CONCLUSIONS: Notch1 may play a significant role in the tumorigenesis and progression of ccRCC. Notch signaling may be a potential target for chemopreventive or adjuvant therapeutics for ccRCC.

Prognostic and Clinicopathological Significance of Transducer-Like Enhancer of Split 1 Expression in Gastric Cancer

PURPOSE: Transducer-like enhancer of split 1 (TLE1) is a member of the Groucho/TLE family of transcriptional co-repressors that regulate the transcriptional activity of numerous genes. TLE1 is involved in the tumorigenesis of various tumors. We investigated the prognostic significance of TLE1 expression and its association with clinicopathological parameters in gastric cancer (GC) patients. MATERIALS AND METHODS: Immunohistochemical analysis of six tissue microarrays was performed to examine TLE1 expression using 291 surgically resected GC specimens from the Soonchunhyang University Cheonan Hospital between July 2006 and December 2009. RESULTS: In the non-neoplastic gastric mucosa, TLE1 expression was negative. In GC, 121 patients (41.6%) were positive for TLE1. The expression of TLE1 was significantly associated with male gender (P=0.021), less frequent lymphatic (P=0.017) or perineural invasion (P=0.029), intestinal type according to the Lauren classification (P=0.024), good histologic grade (P<0.001), early pathologic T-stage (P=0.012), and early American Joint Committee on Cancer stage (P=0.022). In the Kaplan-Meier analysis, the TLE1 expression was significantly associated with longer disease-free (P=0.022) and overall (P=0.001) survival rates. CONCLUSIONS: We suggested that TLE1 expression is a good prognostic indicator in GCs.

Aquaporin 1 Is an Independent Marker of Poor Prognosis in Lung Adenocarcinoma

BACKGROUND: Aquaporin 1 (AQP1) overexpression has been shown to be associated with uncontrolled cell replication, invasion, migration, and tumor metastasis. We aimed to evaluate AQP1 expression in lung adenocarcinomas and to examine its association with clinicopathological features and prognostic significance. We also investigated the association between AQP1 overexpression and epithelial-mesenchymal transition (EMT) markers. METHODS: We examined AQP1 expression in 505 cases of surgically resected lung adenocarcinomas acquired at the Seoul National University Bundang Hospital from 2003 to 2012. Expression of AQP1 and EMT-related markers, including Ecadherin and vimentin, were analyzed by immunohistochemistry and tissue microarray. RESULTS: AQP1 overexpression was associated with several aggressive pathological parameters, including venous invasion, lymphatic invasion, and tumor recurrence. AQP1 overexpression tended to be associated with higher histological grade, advanced pathological stage, and anaplastic lymphoma kinase (ALK) translocation; however, these differences were not statistically significant. In addition, AQP1 overexpression positively correlated with loss of E-cadherin expression and acquired expression of vimentin. Lung adenocarcinoma patients with AQP1 overexpression showed shorter progression-free survival (PFS, 46.1 months vs. 56.2 months) compared to patients without AQP1 overexpression. Multivariate analysis confirmed that AQP1 overexpression was significantly associated with shorter PFS (hazard ratio, 1.429; 95% confidence interval, 1.033 to 1.977; p=.031). CONCLUSIONS: AQP1 overexpression was thereby concluded to be an independent factor of poor prognosis associated with shorter PFS in lung adenocarcinoma. These results suggested that AQP1 overexpression might be considered as a prognostic biomarker of lung adenocarcinoma.

Expression of CCL26 in esophageal squamous cell carcinoma tissues and its clinical significance / 中国癌症杂志

Background and purpose: Chemokines play an important role in cancer occurrence and development. However, little about the function of CCL26 in esophageal squamous cell carcinoma (ESCC) is reported. This study was designed to observe and study the expression of chemokine CCL26 in ESCC tissues and to analyze their association with pathological features of ESCC. Methods: Expressions of chemokine CCL26 in 197 ESCC tissues and their corresponding paraneoplastic normal esophageal tissues were determined by tissue array and immunohistochemistry (IHC) technique, and its correlations to age, gender, lymph nodes metastasis, TNM stage, general classification and 5-year survival rate of ESCC patients were further analyzed. Results: ①CCL26 was expressed in both ESCC and paraneoplastic normal esophageal tissues. The expression of CCL26 in ESCC tissues was signiifcantly higher than that in paraneoplastic normal esophageal tissues (61.8%vs 20.6%, P0.05).③Survival analysis showed that the abnormal expression of CCL26 was associated with 5-year survival rate of patients with ESCC. The 5-year survival rate of ESCC patients with CCL26 positive expression was obviously lower than that of ESCC patients with CCL26 negative expression. Conclusion: CCL26 upexpression might play an important role in the progression and development of ESCC patients. The high level of CCL26 expression is correlated with lymph node metastasis and poor survival. Detection of CCL26 expression may have important prognostic values in ESCC patients.

Prognostic Significance of Tissue Leptin Expression in Colorectal Cancer Patients

PURPOSE: Leptin is encoded by the ob gene and is involved in the control of food intake and energy expenditure. Recent studies have implicated leptin expression to be an indicator of tumor features and prognosis. The purpose of this study was to investigate the association of tissue expression of leptin with the clinicopathological characteristics and clinical outcomes in colorectal cancer patients. METHODS: Patients who had undergone a curative surgical resection for a colorectal adenocarcinoma from 2000 to 2004 were included in the study. Immunohistochemical analyses of leptin expression were performed, and clinicopathological parameters were evaluated. RESULTS: Clinical data and tumor tissues of 146 patients were evaluated. The mean age was 68.6 +/- 11.3 years, and 61.0% were men. Immunohistochemically, the rates of negative, weak, moderate, and strong leptin expression were 2.7% (4 of 146), 5.5% (8 of 146), 43.2% (63 of 146), and 48.6% (71 of 146), respectively. We compared the negative, weak, and moderate expression group (group A) with the strong expression group (group B). Leptin expression was inversely associated with nodal stage (P = 0.007) between the two groups. Leptin expression was not significantly associated with differentiation (P = 0.37), T stage (P = 0.16), and American Joint Committee on Cancer stage (P = 0.49), and no significant differences in the disease-free and the overall survivals (P = 0.78 and P = 0.61) were observed. CONCLUSION: Results demonstrated an inverse association of nodal stage with high leptin expression. Higher leptin expression level might predict better oncologic outcome. However, further studies are warranted to identify the exact role of leptin expression in colorectal cancer.

Estudo das alterações na expressão gênica dos ependimomas / Study of gene expression alterations in ependymomas

Ependimomas são tumores gliais raros. Podem ser encontrados em qualquer localização do sistema nervoso central e, apesar de histologia similar, parecem apresentar alterações genômicas distintas. As variáveis clínicas são intercorrelacionadas e, geralmente, incapazes de predizer o curso da doença. O objetivo do presente estudo foi analisar a expressão aumentada de genes e proteínas em ependimomas e correlacionar com dados clínicos dos pacientes. Foram estudados casos de pacientes com ependimoma submetidos à ressecção cirúrgica no Hospital das Clínicas, Universidade de São Paulo, no período entre 1996 e 2011 (33 amostras de tecido congelado para análise de expressão gênica por PCR quantitativo em tempo real e 149 amostras com tecido incluído em parafina, correspondentes a 121 casos devido a recidivas, para análise de proteína por imuno-histoquímica de tissue microarrays). As reações de imuno-histoquímica foram analisadas semiquantitativamente e graduadas com um índice de marcação calculado pelo produto da porcentagem de núcleos marcados pela intensidade de marcação. Oitenta e um casos eram adultos (média de 27,2 anos). Havia 60 casos intracranianos e 61 intramedulares, dos quais 10 eram mixopapilares, 92 grau II e 19 grau III. Ressecção completa foi possível em 62% dos casos e recidiva foi confirmada em 41,1%. Observou-se menor tempo para recidiva em crianças e tumores intracranianos, supratentoriais (p < 0,001 em ambos), histologia anaplásica e ressecções incompletas (p < 0,05 em ambos). Os seguintes genes foram selecionados em dados públicos de SAGE e literatura: ARMC3, CCND1, CHST5, DNALI1, FGFRL1, GNA13, IGF2, MSX1, NOTCH1 e RSPH3. ARMC3, RSHL3, CHST5 e DNALI1 apresentaram maiores níveis de expressão em ependimomas intramedulares (p < 0,05), e FGFRL1, NOTCH1 e CCND1 nos casos supratentoriais (p < 0,01). IGF2 apresentou maiores níveis de expressão em crianças e CHST5 em adultos (p < 0,05 em ambos). Foram observados maiores níveis de expressão de FGFRL1...

Ependymomas are rare glial cell-derived tumors. They can be found in any central nervous system localization and despite the histological similarity, they seem to display distinct genomic abnormalities. Clinical variables are intercorrelated and they are usually unable to predict the disease course. We aimed to analyze increased gene and protein expression in ependymomas and to correlate with patients' clinical data. We studied patients with ependymoma submitted to surgical resections at Hospital das Clinicas, University of São Paulo, from 1996 to 2011 (33 fresh-frozen samples for gene expression analysis by quantitative real-time PCR and 149 formalin-fixed, paraffin-embedded samples, relative to 121 patients due to relapses, for protein analysis by tissue microarray immunohistochemistry). Immunohistochemical reactions were analyzed semi-quantitatively and scored with a labeling index (LI) calculated as the product of the percentage of the positively stained nuclei by the intensity of staining. Eighty-one cases were adults (mean 27.2 years). There were 60 intracranial and 61 spinal cases, of which 10 tumors were myxopapillary, 92 were grade II and 19 were grade III. Gross total resection was achieved in 62% of cases and relapse was confirmed in 41.4% of cases. We observed a shorther time to relapse in children and supratentorial intracranial tumor localization (p<0.001 for both), anaplastic histology and incomplete resections (p<0.05 for both). The following genes were selected based on public SAGE database and literature: ARMC3, CCND1, CHST5, DNALI1, FGFRL1, GNA13, IGF2, MSX1, NOTCH1 and RSPH3. ARMC3, RSHL3, CHST5 and DNALI1 presented higher expression levels in intramedullary ependymomas (p < 0.05) and FGFRL1, NOTCH1 and CCND1 in supratentorial cases (p < 0.01). IGF2 presented higher expression levels in pediatric cases and CHST5 in adults cases (p < 0.05 in both). Higher expression levels of FGFRLI1 (p < 0.05), CCND1 and IGF2...

RING Finger Proteins Are Involved in the Progression of Barrett Esophagus to Esophageal Adenocarcinoma: A Preliminary Study

BACKGROUND/AIMS: To investigate the differential expression of RING finger (RNF) proteins in Barrett esophagus (BE) and esophageal adenocarcinoma (EAC). METHODS: The differential expression of RNFs in normal esophagus (NE), BE, and EAC was screened using microarray assay. Real-time quantitative polymerase chain reaction (PCR), tissue microarray assay, and Western blot analysis were independently performed to detect the mRNA and protein expression of screened RNFs. RESULTS: The expression of nine RNFs in the BE or EAC was 2-fold higher than those in NE. Among these proteins, the RNF32 and RNF121 expression in BE was 20.3-fold and 16.4-fold higher, respectively, than that in NE, and the expression of RNF24, RNF130, RNF141, RNF139, RNF11, RNF14, and RNF159 was upregulated more than 2-fold compared with NE. The expression of nine RNFs was not only upregulated in the EAC but was also positively related to the RNF expression in BE. The PCR results also indicated increased expression of these RNFs in BE and EAC compared to NE. Furthermore, the mRNA expression of all RNFs, except for RNF141 in EAC, was dramatically higher than those in the BE. Similar results were also obtained from the Western blot analysis. CONCLUSIONS: A total of nine RNFs play critical roles in the progression of BE to EAC.

Carbonic Anhydrase IX is Not a Predictor of Outcomes in Non-Metastatic Clear Cell Renal Cell Carcinoma - A Digital Analysis of Tissue Microarray

Introduction The knowledge about the molecular biology of clear cell renal cell carcinoma (ccRCC) is evolving, and Carbonic Anhydrase type IX (CA-IX) has emerged as a potential prognostic marker in this challenging disease. However, most of the literature about CA-IX on ccRCC comes from series on metastatic cancer, with a lack of series on non-metastatic cancer. The objective is to evaluate the expression of CA-IX in a cohort of non-metastatic ccRCC, correlating with 1) overall survival, and 2) with established prognostic parameters (T stage, tumor size, Fuhrman nuclear grade, microvascular invasion and peri-renal fat invasion). Materials and Methods This is a retrospective cohort study. We evaluated 95 patients with non-metastatic clear cell renal cell carcinoma, as to the expression of CA-IX. The analyzed parameters where: overall survival (OS), TNM stage, tumor size (TS), Fuhrman nuclear grade (FNG), microvascular invasion (MVI), peri-renal fat invasion (PFI). We utilized a custom built tissue microarray, and the immunoexpression was digitally quantified using the Photoshop® software. Results: Th e mean follow-up time was 7.9 years (range 1.9 to 19.5 years). The analysis of CA-IX expression against the selected prognostic parameters showed no correlation. The results are as follows: Overall survival (p = 0.790); T stage (p = 0.179); tumor size (p = 0.143); grouped Fuhrman nuclear grade (p = 0.598); microvascular invasion (p = 0.685), and peri-renal fat invasion (p = 0.104). Conclusion Carbonic anhydrase type IX expression does not correlate with overall survival and conventional prognostic parameters in non-metastatic clear cell renal cell carcinoma. .

Detection of phosphorylated signal transducer and activator of transcription 3 in extravillous trophoblast cells of preeclampsia by placental tissue microarray / 中华围产医学杂志

Objective To construct extravillous trophoblast(EVCT) tissue microarray and detect the expression of phosphorylated signal transducer and activator of transcription 3 (pStat3) in EVCT and to explore the role of Stat3 signal transduction pathway in the pathogenesis of preeclampsia.Methods Placentas of 80 pregnant women with preeclampsia and 58 normal pregnant women hospitalized in the Third Affiliated Hospital of Zhengzhou University from December 12,2007 to December 31,2010 were recruited for constructing EVCT tissue microarray.Vimentin,cytokeratin and human leukocyte antigen-G were used to verify EVCT tissue microarray immunohistochemically.The difference of pStat3 expression was detected between preeclampsia patients and normal pregnant women by immunohistochemical staining.Rank sum test,Kruskai-Wallis H test,t-test and Chisquare test were used for statistical analysis.Results Placental tissues from 57 preeclampsia patients (109 tissue cores) and 31 normal pregnant women (65 tissue cores) were suitable for constructing EVCT tissue microarray.The target tissue was positive for both cytokeratin and human leukocyte antigen-G staining and negative for vimentin,which was in accordance with the characters of EVCT tissue.Totally 86.4％(76/88) samples retained the target EVCT tissues,which meant EVCT tissue microarray was constructed successfully.The expression of pStat3 was significantly decreased in EVCT of preeclampsia patients (51.1％,24/47),the early onset (50.0％,19/38) and severe preeclampsia patients(52.3％,23/44) as compared to normal pregnant women (72.4％,21/29) (U=492.00,473.00 and 401.00,P＜0.05 respectively).Conclusions EVCT tissue microarray has been successfully constructed,and could be used to detect pStat3 expression.pStat3 signal transduction pathway may be involved in the development of preeclampsia.

Expressão diferencial de marcadores relacionados ao ciclo celular e à morte celular entre doença de Alzheimer sintomática e assintomática em cérebros humanos post-mortem / Differential expression of cell cycle and cell death markers between symptomatic and asymptomatic Alzheimer´s disease in post-mortem human brains

A doença de Alzheimer (DA) é caracterizada por um declínio cognitivo progressivo associado ao acúmulo de peptídeo β-amilóide (placas neuríticas), proteína tau hiperfosforilada (emaranhados neurofibrilares), degeneração sináptica e morte neuronal no hipocampo e em outras regiões corticais. Vários estudos apontam uma reativação do ciclo celular em neurônios pós-mitóticos na DA, o que levaria à morte neuronal. Porém, ainda não existe um estudo que avalie marcadores do ciclo celular em indivíduos portadores da neuropatologia típica da DA, mas que não apresentem evidências de comprometimento cognitivo (DA assintomática). Diante disso, este trabalho pretende verificar se existe diferença entre indivíduos com DA sintomática, DA assintomática e indivíduos normais em relação a marcadores do ciclo celular e de morte celular. Nossos resultados mostram alterações significantes de marcadores do ciclo e morte celular nos indivíduos com DA sintomática comparados aos com DA assintomática e aos normais, enquanto que, entre os indivíduos com DA assintomática e sujeitos normais, não existem diferenças significativas. Este trabalho sugere associação entre o controle da maquinaria do ciclo celular nos neurônios pós-mitóticos, e a manutenção do status cognitivo normal...

Alzheimer's disease (AD) is characterized by progressive cognitive decline associated with accumulation of amyloid-β peptide (neuritic plaques), hyperphosphorylated tau protein (neurofibrillary tangles), synaptic degeneration and neuronal death in the hippocampus and in other cortical regions. Several studies indicate a reactivation of the cell cycle in AD post-mitotic neurons, leading to neuronal death. However, studies evaluating cell cycle markers in patients with AD neuropathology, but with no evidence of cognitive impairment (asymptomatic AD) are lacking. Therefore, this study intends to investigate whether there are differences among subjects with symptomatic AD, asymptomatic AD and normal individuals in relation to cell cycle and cell death markers. Our results show significant changes in both cell cycle and cell death markers in subjects with symptomatic AD compared to asymptomatic AD and normal individuals, while between asymptomatic AD individuals and normal subjects, there were no significant differences. This study suggests an association between the control of cell cycle machinery in post-mitotic neurons, and maintenance of normal cognitive status...

In-house Manual Construction of High-Density and High-Quality Tissue Microarrays by Using Homemade Recipient Agarose-Paraffin Blocks

BACKGROUND: Self-made tissue punches can be effectively used to punch holes in blank recipient paraffin blocks and extract tissue cores from the donor paraffin blocks for the low-cost construction of tissue microarrays (TMAs). However, variable degrees of section distortion and loss of the tissue cores can occurs during cutting of the TMAs, posing technical problems for in-house manual construction of high-density TMAs. We aimed to update the method for in-house manual TMA construction to improve the quality of high-density TMAs. METHODS: Blocks of agarose gel were subjected to the standard tissue processing and embedding procedure to prepare recipient agarose-paraffin blocks. The self-made tissue punches and recipient agarose-paraffin blocks were used to construct TMAs, which were completely melted and re-embedded in paraffin to make finished TMA blocks. RESULTS: The donor tissue cores were completely integrated into the surrounding paraffin of the recipient blocks. This method enabled us to construct high-density TMAs with significantly less section distortion or loss of tissue cores during microtomy. CONCLUSIONS: Simple and inexpensive construction of high-density and high-quality TMAs can be warranted by using paraffinized agarose gels as recipient blocks.

An Immunohistochemical Study on the Expression of SUMO-2/3 in the Colorectal Carcinoma

OBJECTIVE: The incidence of colorectal carcinomas continues to rise in Korea due to the westernized life style. However, the precise colorectal carcinogenic mechanisms remain to be elucidated. The protein products of oncogenes and cancer suppressor genes play important roles in the carcinogenesis. The effects of the proteins are influenced by post-translational modifications as phosphorylation, acetylation, methylation, and ubiquitination. The aberrant sumoylation plays some roles in carcinogenesis. However, the expression pattern of small ubiquitin-related modifier (SUMO)-2/3 in the colorectal cancer has not been reported. We assessed the expression of SUMO-2/3 and evaluated the expression pattern in colorectal cancer. METHODS: The SUMO-2/3 expression was tested in one normal colon mucosal cell line and 5 colorectal cancer cell lines by Western blot. We collected 322 cases of colorectal cancer operated from January 2000 to December 2010 at Soonchunhyang University Cheonan Hospital. We fabricated the tissue microarray and the expression of SUMO-2/3 was evaluated by immunohistochemistry. The results were analyzed with clinicopathologic parameters. RESULTS: The SUMO-2/3 was not expressed in the normal colon mucosal cell line. However, it was expressed highly in all the 5 colorectal cancer cell lines as the beta-actin. The SUMO-2/3 was expressed in 68.3% of the colorectal cancers and its expression was correlated with the pathological tumor stage stage (odds ratio, 2.89; 95% confidence interval, 1.10 to 7.55; P=0.031). CONCLUSION: The SUMO-2/3 plays some roles in carcinogenesis and progression of the colorectal cancer.

Construction of High-Density Tissue Microarrays at Low Cost by Using Self-Made Manual Microarray Kits and Recipient Paraffin Blocks

BACKGROUND: Advances of tissue microarray (TMA) technology have enabled simultaneous in situ analysis of biomarker expression in a large number of archived pathology specimens. However, the relatively high cost of TMA construction may hamper many researchers from using this essential tool of modern pathology research. We discuss methods for making TMA kits and recipient blocks for manual construction of high-density TMAs at low cost. METHODS: Ordinary cannula piercing needles, hypodermic needles, bone marrow biopsy needles, metallic ink cartridges of ballpoint pens, and disposable skin biopsy punches were used to construct self-made manual TMA kits. The recipient blocks were manufactured by boring holes in the conventional bare paraffin blocks. A mini electric hand drill and a microcompound table assembled on a drill stand were used to maximize the capacity of the recipient blocks. RESULTS: By using TMA kits made from cannula piercing needles (16- and 18-gauge), it was possible to construct TMAs with 1 mmx140 cores, 0.6 mmx320 cores, 2 mmx70 cores, 3 mmx35 cores, and 5 mmx12 cores. The capacity of the recipient blocks could be dramatically increased by drilling holes. CONCLUSIONS: Construction of TMAs using self-made TMA kits is an inexpensive alternative to construction of TMAs using commercial devices.

IMP3 expression and its relationship with clinicopathological characteristics in breast carcinoma / 临床与实验病理学杂志

Purpose To investigate the expression of IMP3 and its relationship with clinicopathological characteristics in breast cancer.Methods By the tissue microarray technique and immunohistochemical EliVision two-step method, expression of IMP3 was detected in 214 cases of breast carcinoma.Results Of the 214 breast cancer cases,IMP3 expression was seen in 31(14.49%). IMP3 expression in the tumor cells was positively correlated with histological grade (P=0.005), proliferative index labeled by Ki-67 (P=0.033) and triple negative phenotype (P0.05).Conclusions Expression of IMP3 is correlated with higher histologic grade, higher proliferative activity and triple negative breast carcinoma.Our findings indicate that IMP3 plays an important role in breast cancer progression, and IMP3 could be an adjuvant diagnostic marker in triple negative breast carcinoma.

Expression of γ-synuclein in primary osteosarcoma / 第二军医大学学报

Objective: To detect the expression of γ-synuclein in primary osteosarcoma, so as to assess the diagnostic value of γ-synuclein in diagnosis of primary osteosarcoma. Methods: The expression of γ-synuclein in 31 primary osteosarcoma specimens(from 31 patients in our department from Jan. 2004 to Dec. 2005) and 10 benign bone tumor specimens were investigated by tissue array and immunohistochemical method. Results: The expression or overexpression of γ-synuclein was found in 30 of the 31 osteosarcoma specimens; only one female patient's specinmen was negative of it, with a positive rate of 96.8%. All the benign bone tumor specimens had negative expression of γ-synuclein. The positive rate of γ-synuclein was not correlated with age or gender of patients. Conclusion: The γ-synuclein may serve as a marker for osteosarcoma and may be valuable in diagnosis, typing, and prognosis of primary osteosarcoma.

Decreased XAB2 expression and gastric cancer / 第二军医大学学报

Objective: To investigate the changes of XAB2 mRNA and protein expression in gastric cancer tissues, so as to discuss its possible relationship with the development of gastric cancer. Methods: XAB2 mRNA expression in 34 gastric cancer tissues and the matched adjacent normal tissues was examined by real-time RT-PCR. Meanwhile, tissue biochip and immunohistochemistry were employed to examine XAB2 protein expression in gastric cancer tissues, matched adjacent normal tissues, and gastritis tissues. The expression of XAB2 in different tissues and its clinical significance was analyzed. Results: XAB2 mRNA expression in the gastric cancer tissues was significantly lower than that in corresponding adjacent normal tissues (P 0. 05). Conclusion: The lower XAB2 expression might be closely associated with the development and progression of gastric cancer, and further studying may benefit the diagnosis and therapy of gastric carcinoma patients.