Application Of Multicolor Fluorescence In Situ Hybridization To Early Detection Of Chromosome Aberrations In Colorectal Cancer

[Background and Purpose] Detection of chromosome aberrations has been applied to the diagnosis of some cancers. However, there are still no chromosomal markers in colorectal cancer, which accounts for the second death rank of malignancy of women and forth of men in China. This study aimed to reveal the aberrations of some chromosomes in colorectal cancer (CRC) and its premalignant lesions- colorectal adenoma by using multicolor fluorescence in situ hybridization (M-FISH), in order to explore the feasibility and effectiveness of M-FISH in the early diagnosis of CRC and the evaluation of tendency of malignant transformation of the colorectal adenoma.[Patients and Methods] M-FISH was performed in 183 colcrectal lesion biopsy specimens of 161 cases, which included 65 adenoma tissues, 19 adenoma adjacent adenocarcinoma and 99 adenocarcinoma biopsy specimens. Meanwhile, 8 colorectal adenoma biopsy specimens and 8 colorectal cancer biopsy specimens were evaluated with array Comparative Genomic Hybridization (CGH). The relationship between chromosomal aberrations and clinicopathologic parameters was also analyzed.[Results] The copy number gains of chromosomes 7, 8, 12 and 20 were 82.1%(55/67), 70.1%(47/67), 60.9%(56/92) and 72.8%(67/92) in the adenocarcinoma tissues, 76.5%(13/17), 41.2%(7/17), 50%(9/18) and 72.2%(13/18) in the adenoma tissues accompanied adjacent adenocarcinomas.Chromosomal 7 and 20 presented high frequently consistent alterations in adenoma and adenocarcinoma of the same patients.According to the results of array CGH, colorectal adenomas and adenocarcinomas have consistent changes in 10 chromosomal domains, which included 20p, 20q, 7p and 7q. Chromosomes 7 and 20 amplified at the same time is also higher.[Conclusions] High aneuploidy rate of chromosomes 7, 8, 12 and 20 were detected in both colorectal adenocarcimas and adenomas. Aneuploidy rate of Chromosome 7 and 20 may be early warning signs of colorectal cancer. M-FISH may be helpful in the early diagnosis of colorectal adenocarcimas.