• Korean Journal of Veterinary Pathology
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• v.7 no.1
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• pp.11-15
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• 2003

Antigen retrieval (AR) techniques were widely used to recover the antigenicity from the fixed tissues, which were guided by the philosophy of rendering immunohistochemistry (IHC) applicable to routine formalin-fixed, paraffin-embedded tissues for wide application of IHC in research and clinical filed for morphological observation like as anatomy, histology and pathology. Protease antigen recovery (PAR) is an AR technique, which is obtained the antigen retrieve by using enzyme digestion, and commonly used in IHC field. However, during the IHC for the detection of ovine herpesvirus 2 (OvHV-2) antigen, we noted lymphocyte-like cells-specific staining in the infiltrated cells into various organs like as liver and kidney, which was also shown in the IHC tissues with isotype control. However, those signals were not observed in the tissues conducted with in situ hybridization. Therefore, we analyzed the specificity of the IHC detection results. We found that PAR may induce false-positive result during IHC in lymphocyte-like cells, which were infiltrated mainly around vessels and in interstitial tissues. Through the Phenotyping, we realized that those false-positive cells were B-cell-related cells. These results suggest that PAR, a AR using protease, may induce non-specific false-positive reactions during IHC.

• Journal of Gastric Cancer
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• v.16 no.3
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• pp.141-151
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• 2016

Purpose: The aim of the present study was to elucidate the clinicopathological significance and diagnostic accuracy of immunohistochemistry (IHC) for determining the mesenchymal epidermal transition (c-MET) expression in patients with gastric cancer (GC). Materials and Methods: The present meta-analysis investigated the correlation between c-MET expression as determined by IHC and the clinicopathological parameters in 8,395 GC patients from 37 studies that satisfied the eligibility criteria. In addition, a concordance analysis was performed between c-MET expression as determined by IHC and c-MET amplification, and the diagnostic test accuracy was reviewed. Results: The estimated rate of c-MET overexpression was 0.403 (95% confidence interval [CI], 0.327~0.484) and it was significantly correlated with male patients, poor differentiation, lymph node metastasis, higher TNM stage, and human epidermal growth factor receptor 2 (HER2) positivity in IHC analysis. There was a significant correlation between c-MET expression and worse overall survival rate (hazard ratio, 1.588; 95% CI, 1.266~1.992). The concordance rates between c-MET expression and c-MET amplification were 0.967 (95% CI, 0.916~0.987) and 0.270 (95% CI, 0.173~0.395) for cases with non-overexpressed and overexpressed c-MET, respectively. In the diagnostic test accuracy review, the pooled sensitivity and specificity were 0.56 (95% CI, 0.50~0.63) and 0.79 (95% CI, 0.77~0.81), respectively. Conclusions: The c-MET overexpression as determined by IHC was significantly correlated with aggressive tumor behavior and positive IHC status for HER2 in patients with GC. In addition, the c-MET expression status could be useful in the screening of c-MET amplification in patients with GC.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7997-8002
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• 2015

Gene amplification is an important mechanism in the development and progression of cancer. Currently, gene amplification status is generally determined by in situ hybridization (ISH). Multiplex ligation-dependent probe amplification (MLPA) is a PCR-based method that allows copy number detection of up to 50 nucleic acid sequences in one reaction. The aim of the present study was to compare results for HER2, CCND1, MYC and ESR1 gene amplification detected by MLPA with fluorescent in situ hybridization (FISH) and chromogenic in situ hybridization (CISH) as clinically approved methods. Tissue samples of 170 invasive breast cancers were collected. All were ER positive. Tissue samples had previously been tested for HER2 using immunohistochemistry. Amplification of the selected genes were assessed using MLPA, FISH and CISH and results were compared. HER2 MLPA and ISH results were also compared with HER2 immunohistochemistry (IHC) which detects protein overexpression. Amplification of HER2, CCND1, MYC and ESR1 by MLPA were found in 9%, 19%, 20% and 2% of samples, respectively. Amplification of HER2, CCND1, MYC and ESR1 by FISH was noted in 7%, 16%, 16% and 1% of samples, respectively. A high level of concordance was found between MLPA/FISH (HER2: 88%, CCND1: 88%, MYC: 86%, ESR1: 92%) and MLPA/CISH (HER2: 84%). Of all IHC 3+ cases, 91% were amplified by MLPA. In IHC 2+ group, 31% were MLPA amplified. In IHC 1+ group, 2% were MLPA amplified. None of the IHC 0 cases were amplified by MLPA. Our results indicate that there is a good correlation between MLPA, IHC and ISH results. Therefore, MLPA can serve as an alternative to ISH for detection of gene amplification.

• Korean Journal of Veterinary Research
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• v.44 no.4
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• pp.539-549
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• 2004

Mean death time of inoculated embryonated egg is one of the methods to determine the virulence of the Newcastle disease viruses (NDV). Evaluation of tissue tropism of NDV in the host has been proposed as an another way to determine the pathogenicity of NDV based on the principal site of viral replication. To evaluate the tissue tropism among NDV, an immunohistochemistry(IHC) technique using monoclonal antibody was applied in one-day-old SPF chickens inoculated with different ND vaccine strains such as Ulster 2C, VG/GA and B1 viruses by eye drop instillation. The tissues used for this comparison were trachea, intestine, Harderian gland and cecal tonsil, which were collected at 0.5, 1, 2, 3, 5, 8, 10, 14 days post inoculation. Among test groups, chickens inoculated with B1 viurs, which is known to replicate in the respiratory system, have IHC positive staining mainly in the trachea and those inoculated with Ulster 2C have IHC positive staining mainly in the intestine. However, chickens inoculated with VG/GA strain have IHC positive staining in both the trachea and intestine. Therefore, a differences in tissue tropism among ND vaccine strains has been proved by the IHC technique. Based on this results, the IHC staining technique could be used to classify the NDV or to study the pathogenesis of NDV in chickens.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8395-8400
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• 2014

In Saudi Arabia, cancer of breast is ranked the most frequent neoplasm and second source of cancer death in the female population. Breast cancer (BC) fast diagnosis, prognosis and medication management necessitate, these days, immunohistochemistry (IHC) assessment of hormone receptors and HER2 expression profile. The present report defines the IHC profile of ER, PR and HER2 in Saudi female breast neoplasms of ductal and lobular types and associations ER, PR and HER2 expression patterns with various clinicopathological factors (age, type of tumor, size, laterality, histological grade, and involvement of axillaries lymph nodes). Ninety nine cases of breast tumors were recruited from the pathology department archive of King Abdulaziz University Hospital, Kingdom of Saudi Arabia. ER, PR and HER2 expression was assessed using IHC staining. Ductal carcinomas with a variety of histological grades constituted 88 (88.8%) of total cases. Seventy four (77.8%), 59 (62.1%), and 35 (36.8%) of ductal carcinomas showed positive staining for ER, PR and HER2, in that order. Remaining breast cancer cases were four (4%) lobular carcinomas and two (2%) mixed form of ductal and lobular types, which were ER+, PR+, and HER2-. Breast cancer expression pattern of ER, PR and HER2 in Saudi female is different from that of Tunisian and Jordanian female populations and closer to the expression pattern of Egyptian, Lebanese, Iraqi and western country females. Furthermore, the present study found two IHC patterns of breast cancer ER+/PR-/HER2+ (5%) and ER+/PR-/HER2- (11.1%), which had not been reported in other Arabic studies. Thus the rates of IHC expression patterns in breast cancer show some variation among Arabic female populations.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.2
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• pp.421-425
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• 2015

Background: This study was performed to evaluate the amplification of HER-2/neu in patients with melanoma. Materials and Methods: Amplification of HER-2/neu was evaluated in a group of patients with melanoma, referred to two referral centers in Tehran, using immunohistochemistry (IHC) and chromogenic in situ hybridization (CISH) techniques. Results: Forty patients with mean age $57.9{\pm}19.5years$ were enrolled in this study. The most frequent type of melanoma was acral, while lower limbs were the most frequent sites. The amplification of HER2/neu was negative in 97.5% of patients with IHC and in 100% of patients with CISH technique. Only one case (2.5%) shows weak positive staining (+2) in IHC method. Fifty five percent of melanoma was ulcerative, and the most common stages of tumors were stages 4b and 3b. More than 47% of cases were in Clark level III, while the mean of Breslow thickness was $3.56{\pm}2.87mm$. The stage of the case that showed weakly positive staining (2+) in IHC was 4b. Conclusions: The amplification of HER2/neu biomarker was negative in patients with melanoma, using both CISH and IHC techniques.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.5731-5734
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• 2013

Background: The object of this study was to examine whether a new protocol including step-sectioning and immunohistochemistry (IHC) staining of axillary sentinel nodes (SN) would lead to detection of more metastases in patients with breast cancer. Materials and Methods: Sixty-nine tumor free sentinel lymph nodes were examined. Step frozen sectioning was performed on formalin fixed SN and stained both by hematoxylin and eosin (H and E) and cytokeratin markers using IHC. Any tumoral cell in IHC stained slides were considered as a positive result. Metastases up to 0.2 mm were considered as isolated tumor cells and 0.2 up to 2 mm as micrometastasis. Results: Mean age of the patients was $48.7{\pm}12.2$ years. Step sectioning of the SN revealed 11 involved by metastasis which was statistically significant (p<0.001). Furthermore, 15 (21.7%) of the patients revealed positive results in IHC staining for pan-CK marker and this was also statistically significant (p=0.001). Ten patients had tumoral involvement in lymph nodes harvested from axillary dissection and 4 out of 15 lymph nodes with positive result for CK marker were isolated tumor cells. However, 4 of 10 patients with tumor positive lymph nodes in axillary dissection were negative for CK marker and in contrast 6 of the pan-CK positive SN were in patients with tumor-free axillary lymph nodes. Conclusions: Both IHC and step sectioning improve the detection rate of metastases. Considering the similar power of these two methods, we recommend using either IHC staining or step sectioning for better evaluation of harvested SNs.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5477-5482
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• 2012

Background: The HER-2/neu gene is altered in 15-20% of breast cancer patients. Immunohistochemistry (IHC) is considered to be the most cost-effective method for HER-2 detection in many countries. Approximately 8,000 new cases of breast cancer are observed annually in Iran. The aims of this study were to conduct a systematic review of the literature on the rate of HER-2-positive breast cancer diagnosed by IHC in Iran. Methods: A systematic search of the medical literature using the Medline/PubMed, ISI and SID databases revealed articles published in the English and Persian languages evaluating HER-2-positive breast cancer in Iran. Results: From 22 studies, 3,033 patients were evaluated, of whom 1,350 were diagnosed as HER-2-positive by IHC HER-2 testing. The mean percentage of HER-2-positive patients was 44.5%, which is higher than that recorded in international statistics. Results of this meta-analysis showed a significant heterogeneity between ratios. There was a statistically significant difference between the results of pre- and post implementation of 2007 American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) guideline. IHC HER-2 testing has been performed in Iran for over 10 years. Similar to many other countries, before establishment of an infrastructure for IHC diagnostic tests, HER-2 testing was routinely performed in Iran. Our study showed that the statistics reported from Iran varied widely; for instance, the rate of HER-2-positive cases varied from 23.3% to 81.0%. Conclusions: Our results demonstrate that the lack of standardization and harmonization of this test have led to marked variations in breast cancer diagnosis in Iran.

• Journal of Gastric Cancer
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• v.23 no.2
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• pp.264-274
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• 2023

Purpose: In this study, polymerase chain reaction (PCR)-based microsatellite instability (MSI) testing was comprehensively analyzed and compared with immunohistochemistry (IHC) for mismatch repair (MMR) protein expression in patients with gastric cancer (GC). Materials and Methods: In 5,676 GC cases, PCR-based MSI testing using five microsatellites (BAT-26, BAT-25, D5S346, D2S123, and D17S250) and IHC for MLH1 were performed. Reevaluation of MSI testing/MLH1 IHC and additional IHC for MSH2, MSH6, and PMS2 were performed in discordant/indeterminate cases. Results: Of the 5,676 cases, microsatellite stable (MSS)/MSI-low and intact MLH1 were observed in 5,082 cases (89.5%), whereas MSI-high (MSI-H) and loss of MLH1 expression were observed in 502 cases (8.8%). We re-evaluated the remaining 92 cases (1.6%) with a discordant/indeterminate status. Re-evaluation showed 1) 37 concordant cases (0.7%) (18 and 19 cases of MSI-H/MMR-deficient (dMMR) and MSS/MMR-proficient (pMMR), respectively), 2) 6 discordant cases (0.1%) (3 cases each of MSI-H/pMMR and MSS/dMMR), 3) 14 MSI indeterminate cases (0.2%) (1 case of dMMR and 13 cases of pMMR), and 4) 35 IHC indeterminate cases (0.6%) (22 and 13 cases of MSI-H and MSS, respectively). Finally, MSI-H or dMMR was observed in 549 cases (9.7%), of which 47 (0.8%) were additionally confirmed as MSI-H or dMMR by reevaluation. Sensitivity was 99.3% for MSI testing and 95.4% for MMR IHC. Conclusions: Considering the low incidence of MSI-H or dMMR, discordant/indeterminate results were occasionally identified in GCs, in which case complementary testing is required. These findings could help improve the accuracy of MSI/MMR testing in daily practice.

• Korean Journal of Veterinary Research
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• v.53 no.1
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• pp.1-5
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• 2013

The obligatory intracellular protozoan parasite Toxoplasma gondii is a major world wide cause of infectious ovine abortion. In some different diagnostic techniques that are being used to detect this pathogen in ovine fetuses, immunohistochemistry (IHC) is a very sensitive and expensive one. Histopathology is not truly a specific and sensitive test for Toxoplasma infection but it can be helpful to choose some suspected tissues for IHC. In this study 9.5% of 200 samples (aborted ovine fetuses internal organs such as brain, liver, heart, lung, kidney, spleen) (4.6~14.4% with 95% CI) were positive in IHC with a very good logical agreement among different diagnostic techniques (${\kappa}=0.73$, 0.8) and with no significant difference among different fetal age groups (p > 0.05).