Chromogenic in situ hybridization

A diagnostic method using fluorescence labeled DNA probes to detect and quantify the number complementary chromosomal sequences on a cellular resolution. A related technique that also allows assessment of gene amplifications, but without precise quantification of copy numbers is the chromogenic in situ hybridization (CISH). Here, instead of a fluorescent dye an enzyme that can generate a colored precipitate in the tissue samples is coupled to the DNA probe. 

The complexities of protocols for fluorescent and chromogenic in situ hybridization necessarily entail careful attention to controls. In particular, the possibility of native enzyme activity or the presence of endogenous biotin in the experimental tissue should be considered, though this can be addressed by exposing control tissue to the detection system in the absence of probe. The relative merits of digoxigenin versus biotin, and some of the technical problems associated with each, have been previously discussed (Chevalier et al., 1997 Luo and jackson, 1999). 

Kim H, Choe J, Yoo S et al (2011) Detection of ALK gene rearrangement in non-small-cell lung cancer a comparison of fluorescence in situ hybridization and chromogenic in situ hybridization with correlation of ALK protein expression. I Thorac Oncol 6 1359-1366... 

Yoshida A, Tsuta K, Nitta H et al (2011) Bright-field dual color chromogenic in situ hybridization for the diagnosis of EML4-ALK-postitive lung adenocarcinomas. J Thorac Oncol 6 1677-1686... 

Under such circumstances, the chromogenic in situ hybridization (CISH) technique has been attracting attention in recent years. It is a well-known technique and has already been approved for HER2 testing [15,16], There are two major CISH methods used in HER2... 

Lacroix-Triki M, Mounie E, Charafe-Jauffret E, et al. Double staining chromogenic in situ hybridization is a useful alternative to fluorescent in situ hybridization first comparative study of HER2 and TOP2A gene amplification in breast cancer. Proc. San. Antonio Breast Cancer Symp. 2007. 

Gong Y, Gilcrease M, Sneige N. Reliability of chromogenic in situ hybridization for detecting HER-2 gene status in breast cancer comparison with fluorescence in situ hybridization and assessment of interobserver reproducibility. Mod Pathol 2005 18(8) 1015-21. 

Hauser-Kronberger C, Dandachi N. Comparison of chromogenic in situ hybridization with other methodologies for HER2 status assessment in breast cancer. J Mol Histol 2004 35(6) 647-53. 

Bhargava R, Lai P, Chen B. Chromogenic in situ hybridization for the detection of HER-2/neu gene amplification in breast cancer with an emphasis on tumors with borderline and low-level amplification does it measure up to fluorescence in situ hybridization Am J Clin Pathol 2005 123(2) 237-43. 

Laakso M, Tanner M, Isola J. Dual-colour chromogenic in situ hybridization for testing of HER-2 oncogene amplification in archival breast tumours. J Pathol 2006 210(1) 3-9. 

Recent literature also explored chromogenic in-situ hybridization (CISH) as a method of choice for detection of EGFR copy number in FFPE tissue. The results showed good correlation with FISH analysis, however chromosome 7 polysomy cannot be readily distinguished from EGFR amplification. The importance of distinguishing polysomy from gene amplification is still uncertain. 

FISH, Fluorescence in situ hybridization CISH, chromogenic in situ hybridization (generally DAB as chromogen) SISH, silver in situ hybridization. 

Tarmer M, Gancberg D, Di Leo A, et al. Chromogenic in situ hybridization A practical alternative for fluorescence in situ hybridization to detect HER-2/neu oncogene amplification in archival breast cancer samples. Am J Pathol. 2000 157 1467-1472. 

Chromogenic in situ hybridization (CISH) is a recent methodology wherein the HER2/neu gene copies are detected by a silver reaction and visualized by light microscopy. A study that evaluated CISH on ThinPrep-processed hne-needle aspirate specimens found a good concordance between CISH performed on LBC specimens as compared to paraffin-embedded tissue specimens. 

Peiro G, Mayr D, Hillemanns P, et al. Analysis of HER-2/neu amplification in endometrial carcinoma by chromogenic in situ hybridization. Correlation with fluorescence in situ hybridization, HER-2/neu, p53 and Ki-67 protein expression, and outcome. Mod Pathol 2004, 17, 1-11. 

Dandachi N, Dietze O, Hauser-Kronberger C. Chromogenic in situ hybridization a novel approach to a practical and sensitive method for the detection of HER2 oncogene in archival human breast carcinoma. Lab Invest 2002, 82, 1007-1014. 

Zhao J, Wu R, Au A, et al. Determination of HER2 gene amplification by chromogenic in situ hybridization (CISH) in archival breast carcinoma. Mod Pathol 2002, 35, 657-665. 

Park K, Kim J, Lim S, et al. Comparing fluorescence in situ hybridization and chromogenic in situ hybridization methods to determine the HER2/neu status in primary breast carcinoma using tissue microarray. Mod Pathol 2003, 16, 937-943. 

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