scholarly journals Correlation Between MYCN Gene Status and MYCN Protein Expression in Neuroblastoma: A Pilot Study To Propose the Use of MYCN Immunohistochemistry in Limited-Resource Areas

2019 ◽  
pp. 1-7
Author(s):  
Teresa Santiago ◽  
Nidale Tarek ◽  
Fouad Boulos ◽  
Caleb Hayes ◽  
Sima Jeha ◽  
...  

PURPOSE The most significant adverse risk factor for neuroblastoma (NB) is MYCN gene amplification, which strongly associates with high-risk disease. Fluorescent in situ hybridization (FISH) is considered the best method to evaluate MYCN gene status. However, it requires a laboratory that can perform highly complex testing, specialized personnel, and costly reagents. Herein, we aimed to investigate the feasibility of using immunohistochemistry (IHC) to detect MYCN protein expression in lieu of FISH, a strategy potentially useful in areas with limited resources. METHODS A pilot cohort of 78 patients with NB, including 34 of Middle Eastern descent (MED) who had a higher prevalence of MYCN gene amplification (44.11%) and 44 of North American descent (NAD), nine (20.45%) of whom had MYCN amplification, was evaluated with IHC for MYCN protein. Correlations of FISH results and protein expression are presented. RESULTS A positive correlation between MYCN gene amplification and protein expression by IHC was seen in 22 (91.66%) of the 24 MYCN-amplified NB cases—14 (93.33%) of 15 patients of MED and eight (88.88%) of nine patients of NAD. Agreement between negative FISH and negative IHC results was noted in 18 (94.73%) patients of MED and 34 (97.14%) patients of NAD. Two cases had weak protein expression but no gene amplification (MED: n = 1; 5.0%; NAD: n = 1; 2.9%). CONCLUSION An excellent overall correlation between MYCN gene status by FISH and MYCN protein expression by IHC was confirmed. MYCN IHC in NB with reflexing to FISH in equivocal cases is potentially useful in a limited-resource setting. Evaluation of effectiveness using a larger cohort and optimization to perform MYCN IHC manually is needed.

2018 ◽  
Vol 56 (2) ◽  
pp. 230-238 ◽  
Author(s):  
Luisa Vera Muscatello ◽  
Enrico Di Oto ◽  
Giuseppe Sarli ◽  
Valentina Monti ◽  
Maria Pia Foschini ◽  
...  

Human epidermal growth factor receptor 2 (HER2) is a tyrosine kinase receptor overexpressed in a subset of breast cancer due to HER2 gene amplification. HER2 protein is expressed in feline mammary carcinomas, but little is known about its cytogenetic alterations. The aim of this study was to evaluate HER2 gene amplification status and its correlation with HER2 protein expression in feline mammary carcinomas. Feline mammary carcinomas were retrospectively selected and immunohistochemically (IHC) evaluated for HER2 protein expression. All the HER2 IHC-positive (3+) and equivocal (2+) cases and a subset of negative cases (0/1+) were selected for fluorescence in situ hybridization (FISH). Dual-core tissue microarrays were prepared for FISH. IHC and FISH were evaluated according to the 2013 American Society of Clinical Oncology/College of American Pathologists guidelines. The study included 107 feline mammary carcinomas from 88 queens. HER2 protein expression was positive (3+) in 7 cases (6.5%), equivocal (2+) in 48 cases (45%), and negative (0/1+) in 52 cases (48.5%). HER2 status was indeterminate in 8 feline mammary carcinomas (12%), amplified in 3 (4%), equivocal in 4 (6%), and nonamplified in 53 (78%). HER2 gene amplification and protein expression were significantly positively correlated ( R = 0.283; P < .0001). HER2 gene is amplified in a subset of feline mammary carcinomas despite the HER2 positive or equivocal protein expression, but it remains to be determined if the HER2 amplification is a gene alteration that drives mammary tumor carcinogenesis or only a bystander passenger mutation.


2007 ◽  
Vol 25 (18_suppl) ◽  
pp. 6023-6023
Author(s):  
P. Weinberger ◽  
A. Psyrri ◽  
P. Kountourakis ◽  
T. Rampias ◽  
C. Sasaki ◽  
...  

6023 Background: EGFR overexpression correlates with recurrence and with treatment resistance in HNSCC. The mechanisms of EGFR protein overexpression are poorly understood. Nonetheless, previous investigators have not demonstrated a correlation between EGFR gene copy number and protein content, using conventional immunohistochemistry (IHC). The aim of this study was to evaluate the relationship of EGFR gene copy number and protein expression utilizing fluorescence in situ hybridization (FISH) and AQUA, a novel, immunohistochemical method of automated quantitative in situ proteomic analysis which permits subcellular localization. Methods: A tissue microarray composed of 137 HNSCC treated with (chemo)radiation was constructed and analyzed for EGFR copy number by FISH (Vysis/Abbot) and EGFR protein expression (DAKO antibody) using AQUA analysis of EGFR staining scored on a scale of 0–255 and by conventional IHC. Agreement was assessed using kappa. Results: Sixteen (15%) of one-hundred six tumors with FISH results demonstrated EGFR high polysomy and/or gene amplification (FISH+). AQUA demonstrated a range of 3.6–102.2; protein levels assessed by AQUA in the FISH amplified cases were significantly higher (p =0.008) than in the FISH non- amplified ones. Using the EGFR 75th percentile as a cut-off, AQUA and FISH showed significant agreement (percentage of overall agreement 82%, kappa=0.458, p=0.003). To the contrary there was no concordance between FISH and conventional IHC results in this series. Conclusions: The discrepancy between EGFR gene amplification rate and protein expression by IHC reported previously may be due to the limitations and nonquantitative nature of conventional IHC. EGFR protein content correlates with gene copy number if protein content is quantitated and automatically analyzed, as with AQUA. No significant financial relationships to disclose.


2019 ◽  
Vol 7 (12) ◽  
pp. 1917-1925
Author(s):  
Ali Hussein Mohammed Ali ◽  
Alaa Qasim Yahya ◽  
Haider Latteef Mohammed

BACKGROUND: The rapidly growing knowledge regarding factors controlling tumour growth, with the new modalities of therapy acting on the biological activity of the tumours draw the attention of most cancer researches nowadays and represent a major focus for clinical oncology practice. For the detection of HER2/neu protein overexpression and gene amplification, immunohistochemistry (IHC) and in-situ hybridisation (ISH) is the recommended techniques, respectively, with high concordance between the two techniques. The current United Kingdom recommendations for HER2/neu testing are either for a two-tier system using IHC with reflex ISH testing in equivocal positive cases, or a one-tier ISH strategy. AIM: To compare the results of HER2/neu gene status in patients with breast carcinoma obtained by chromogenic in situ hybridisation with those obtained by immunohistochemistry, and to compare these results with hormonal receptors expression by immunohistochemistry and with age of patients.METHODS: Immunohistochemistry technique was used for evaluation of status of estrogen receptors (ER) and progesterone receptors (PR) and HER2/neu protein expression in 448 Iraqi patients with invasive breast carcinoma with different grades and histological types and then chromogenic in situ hybridization (CISH) technique was applied for all scores of HER2/neu to detect the gene status and compare the results in all negative, equivocal and positive cases by immunohistochemistry (IHC). The cases were referred from different centres, and IHC and CISH techniques were done in central public health laboratory in Baghdad over 28 months, from July 2013 to November 2015. A comparison of the results was made to find the relationship between HER2/neu and hormone receptors status and other clinical parameters like patients age. RESULTS: The mean age of the study cases was 49.08 years, ranging from 24 to 83 years. Of the 448 cases of breast carcinoma, 44 (9.8%) cases were of score 0 by IHC, none of them (0%) showed HER2/neu gene amplification by CISH. 71(15.8%) cases were of score 1 by IHC, 15 (21.12%) of them showed HER2/neu gene amplification by CISH, all were of low amplification. There were 306 (68.3%) cases of score 2 by IHC, of which 102 (33.33%) cases showed HER2/neu gene amplification by CISH, with 79 (25.81%) of them with low amplification and 23 (7.51%) cases with high amplification, while only one case (0.32%) remained in equivocal category. In score 3, all the 27 (6.0%) cases showed gene amplification with 12 (44.44%) cases with low amplification and 15 (55.55) cases with high amplification with overall percentage of gene amplification in score 3 of 100%. There was a significant inverse relationship between hormone receptors (ER and PR) status and HER2/neu gene amplification. No significant relationship was found between the patient’s age and HER2/neu gene amplification.CONCLUSION: Although immunohistochemistry is a widely used, less expensive and reliable test, we strongly advice performance of chromogenic in situ hybridization in assessment of HER2/neu gene status in all cases diagnosed with breast carcinoma as significant number of cases that were reported as negative by immunohistochemistry showed positive amplification by chromogenic in situ hybridization and can get benefit from anti-HER2 targeted treatments.


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