Molecular cytogenetic analyses of hTERC (3q26) and MYC (8q24) genes amplifications in correlation with oncogenic human papillomavirus infection in Czech patients with cervical intraepithelial neoplasia and cervical carcinomas

Abstract

It is known that cervical cancer develop from precancerous intraepithelial neoplasia (CIN) which is characterized by series of genetic abnormalities. The progression of CIN to cervical carcinoma has been associated especially with the genomic integration of oncogenic human papilloma virus (HPV) and gain of the human telomerase RNA gene hTERC (3q26) and MYC (8q24).In this study, cytology specimens of cervical intraepithelial neoplasia and cervical carcinoma from 74 Czech women were analyzed using the triple-color Cervical FISH Probe Kit designed for identification of HPV infected cells and copy number aberration of the hTERC and MYC genes. HPV-positivity exhibited 70% of patients with premalignant lesions (CIN I -CIN III, carcinoma in situ), chromosomal changes were found in 53.3% of cases -MYC amplification had 33.3% of women with CIN I -CIN III and 50% with carcinoma in situ. Amplification of hTERC was detected in 16.7% of patient with CIN I, in 50% with CIN II, in 58.3% with CIN III and in 66.7% with carcinoma in situ. Based on HPV-positivity and the occurrence of chromosomal aberrations, patients were divided into high-, intermediate-and low-risk group.Among women with cervical carcinomas, HPV infection was detected in 90.1% of specimens and chromosomal aberrations were found in 87.5% of samples. Amplification of MYC gene was detected in 25% and hTERC gene in 62.5% of patients. According to the histopathological grade of tumors, MYC gene amplification occurred more frequently in specimens of spinocellular carcinoma than adenocarcinoma (p=0.029). We found no association between the frequency of cytogenetic lesions and the incidence of lymphangiogenesis or lymph node metastases in cervical carcinoma patients. Simultaneous hTERC and MYC genes amplification was significantly more frequent in samples of cervical carcinomas than in premalignant lesions (p=0.008).In a cohort of 26 patients with cervical carcinoma we used oligo-based GGH+SNP microarray technique for the high resolution mapping of copy number changes of hTERC and MYC genes. We found that recurrent gain of genetic material in chromosome 3q26 area carrying hTERC gene of size 43.6 Mb between 3q25.1-3qter and duplication of 3q were the most common genomic identifications of amplified gene. In MYC locus array-CGH profiling identified duplication of 8q and trisomy 8 as frequent genomic changes.Our work confirmed that in cervical carcinoma gains of hTERC and MYC genes are specific genomic changes associated with developing of malignant phenotype. We also showed that in premalignant stages HPV-FISH assay can be used as an effective diagnostic procedure to identify patients carrying highly risking HPV infection and chromosomal aberrations associated with this malignancy.

Identification of SEC62 as a potential marker for 3q amplification and cellular migration in dysplastic cervical lesions

“…These results agree with previous studies reporting a comparable incidence for the amplification of the entire 3q26 region in precancerous cervical lesions and cervical cancer [41], suggesting that the SEC62 gene harbors an oncogenic function. However, there are other potential 3q26-encoded oncogenes with a similar pattern of amplification and overexpression in dysplastic cervical lesions including hTERC , LAMP3 and PIK3CA [42–45]. Kuglik et al reported that gains of the hTERC gene are specific genomic changes in cytological specimens of the uterine cervix associated with the progression to a malignant phenotype [42].…”

“…However, there are other potential 3q26-encoded oncogenes with a similar pattern of amplification and overexpression in dysplastic cervical lesions including hTERC , LAMP3 and PIK3CA [42–45]. Kuglik et al reported that gains of the hTERC gene are specific genomic changes in cytological specimens of the uterine cervix associated with the progression to a malignant phenotype [42]. Furthermore, a meta-analysis of 12 studies evaluating the diagnostic value of hTERC in dysplastic cervical lesions found that the detection of hTERC amplification is a valuable marker for high-grade cervical lesions and invasive cancer [43].…”

Detection of oncogenic mutations in cervical carcinoma using method High Resolution Melting (HRM)

“…Molecular cytogenetic analysis by FISH technique was accomplished using the commercial kit Vysis Cervical FISH Probe (Abbott Molecular, Illinois, USA). The kit enables the simultaneous detection of HPV-infected cells and the amplification of chromosomal regions 3q26 (hTERC gene) and 8q24 (MYC gene) as described previously [7,25]. For the whole-genome screening of chromosomal abnormalities by array-CGH, we used a platform of oligonucleotide-based DETECTION OF MUTATIONS IN CERVICAL CARCINOMA By METHOD HRM DNA microarrays SurePrint G3 CGH+SNP Array 180K (Agilent Technologies, Santa Clara, CA, USA).…”

“…Consequently we evaluated the results of mutation analysis in the relationship to clinical characteristics of the disease. Simultaneously, we studied possible correlations between the gene mutations or DNA sequence changes and the presence of chromosomal abnormalities which were detected by methods of HPV-FISH (fluorescence in situ hybridization for the detection of human papillomavirus in cells) and array-CGH (array-based comparative genomic hybridization) realized in the scope of our previous studies [7,25].…”

Prognostic value of fluorescence in situ hybridization assay for neoplastic changes in the cervix uteri

“…Не менее важным маркером при высокой степени неоплазии и инвазивном раке шейки матки оказалась также амплификация локуса 8q24 (ген С-MYC) [42]. Хотя у пациенток с цервикальной карциномой амплификация этого гена наблюдалась в меньшей степени по сравнению с ча-стотой гена hTERC (25 и 62,5% соответственно) [50].…”