Secondary genetic alterations overcome tumor suppressive mechanisms and allow the progression to intermediate lesions characterized by TERT-p mutation or to invasive melanomas displaying disruption of tumor suppressor genes.
Our data provides additional evidence that UV-induced <i>TERT</i> promoter mutation frequencies vary depending on melanoma subtype, but preserves its prognostic value.
Hot spot mutations in the promoter region of telomerase reverse transcriptase (TERT promoter mutations) occur frequently in tumors of neuroectodermal origin such as melanoma and glioma.
The recent identification of a high frequency of driver mutations in the promoter of the telomerase reverse transcriptase (TERT) gene in cutaneous melanoma led us to investigate whether these mutations also occur in SNMM.
In particular, mutations of the telomere binding proteins alpha thalassemia/mental retardation syndrome X-linked (ATRX) or death-domain associated protein (DAXX) have been shown to underlie a telomere maintenance mechanism not involving telomerase (alternative lengthening of telomeres), and point mutations in the promoter of the telomerase reverse transcriptase (TERT) gene increase telomerase expression and have been shown to occur in melanomas and a small number of other tumors.
The recent technological advances have allowed the identification of new genes involved in melanoma susceptibility: breast cancer 1 (BRCA1), BRCA1-associated protein 1 (BAP1), and telomerase reverse transcriptase (TERT).Tests on these genes allow to identify a larger number of high-risk individuals with a potential of developing familial melanoma and primary multiple melanomas.
TERT mutations were found in 68% of primary melanomas and 64% of metastases, and the mutation status was discordant between primary tumour and metastasis in 24% of the cases.
TERT positivity as a test for melanoma versus nevus had an accuracy of 87.3% [95% confidence interval (CI), 81.1-92.1], a sensitivity of 77.9% (95% CI, 68.9-85.4), a specificity of 98.6% (95% CI, 95.8-100), a positive predictive value of 98.5% (95% CI, 95.6-100), and a negative predictive value of 78.9% (95% CI, 72.6-85.4).
We observed statistically significant associations with melanoma for two lung cancer SNPs in the TERT-CLPTM1L locus (Bonferroni-corrected p<2.8x10-4), replicating known pleiotropic effects at this locus.
In the melanoma dataset, two pancreatic cancer susceptibility variants were associated: NR5A2 (rs12029406; OR, 1.39; 95% CI, 1.01-1.92; P = 0.04) and CLPTM1L-TERT (rs401681; OR, 1.16; 95% CI, 1.01-1.34; P = 0.04).
The recent identification of driver mutations in the promoter of the telomerase reverse transcriptase (TERT) gene with UV-induced cytidine-to-thymidine transitions in cutaneous melanoma prompted us to investigate whether these mutations also occur in uveal melanoma.
Recurrent and mutually exclusive C>T or CC>TT transition mutations were identified in the promoter region of the reverse transcriptase catalytic subunit of the telomerase gene (TERT) in melanoma recently, and it was suggested that they enhanced the expression of TERT gene and played important roles in the melanoma pathogenesis.
Two recurrent point mutations in the promoter region of telomerase reverse transcriptase (TERT)--the key subunit of telomerase--have recently been identified in melanoma as well as a small sample of bladder cancer cell lines.
In this study, we investigated the impact of the subtypes of TERT mutations on disease-free and melanoma-specific survival in 287 patients with stage I/II nonacral melanoma.
Leukemia cell lines K-562, its vincristine-resistant derivative K-562-Lucena1 and daunorubicin-resistant derivative FEPS; gastric adenocarcinoma lines AGP01, ACP02 and ACP03; melanoma SK-Mel-103 cells; and MN01 and MRC5, two non-neoplastic cell lines were analyzed by real-time polymerase chain reaction in order to evaluate hTERT gene expression.
We investigated the regulation of TERT expression in melanoma cell lines and our results show that promoter mutations render TERT expression dependent on MAPK activation due to oncogenic BRAF or NRAS mutations.
To elucidate this question, ETS1 and TERT immunohistochemistry were performed on a panel of benign (n=27) and dysplastic nevi (n=34), radial growth phase (n=29), vertical growth phase (n=25) and metastatic melanomas (n=27).