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N observed that in patients affected by several neoplastic diseases plasma DNA contains longer fragments than in healthy subjects [4?0] reflected by the increase of DNA integrity index.Cell-Free DNA Biomarkers in MelanomaThe above mentioned parameters can obviously be KDM5A-IN-1 web considered as non-specific biomarkers, since the increase of cfDNA concentration and integrity is common to the large majority of human solid cancers. When cfDNA is used to detect genetic and epigenetic modifications in a specific tumor, it is necessary to select definite molecular targets that are expected to be altered in affected patients. In cutaneous melanoma, the oncogene BRAF is frequently mutated. BRAF is a serine hreonine protein kinase involved in the RAS AF EK RK pathway [11] which regulates cell growth, survival, differentiation and senescence [12]. The oncogene BRAF is frequently mutated in other human cancers constitutively activating the MAPK pathway. The most common BRAF mutation, which accounts for more than 90 of cases of cancer involving this gene, is the T1799A transversion, converting valine to glutamic acid at position 600 (V600E) [13]. BRAF somatic mutations have been reported in 66 of malignant melanomas [13] and are likely to be a crucial step in the initiation of melanocytic neoplasia, as they are found also in melanocytic nevi [14]. BRAF mutations are an attractive target for therapeutic interventions, as they represent an early event in melanoma pathogenesis and are preserved throughout tumor progression [15]. Specific inhibitors of mutant BRAF, such as PLX4032, were developed and tested in clinical trials showing response rates of more than 50 and improved rates of overall and progression-free survival in patients with metastatic melanoma with the BRAFV600E genetic variant [16]. BRAFV600E mutation has been investigated as a marker in cfDNA from melanoma patients by Daniotti et al. [17] and Yancovitz et al. [18]. Finally, it is 301353-96-8 site widely demonstrated that a limited number of genes is epigenetically disregulated in cutaneous melanoma. RASSF1A (Ras association domain family 1 isoform A) is a tumor suppressor gene, which regulates mitosis, cell cycle and apoptosis [19]. It is inactivated mostly by inappropriate promoter methylation in many types of cancers [19]. RASSF1A promoter is methylated in 55 of cutaneous melanomas [20]. Methylation of RASSF1A increases significantly with advanced clinical stage, suggesting that inactivation of this gene is associated with tumor progression [21]. RASSF1A promoter hypermethylation has been detected in cfDNA from melanoma patients [22?3] in association with a worse response to therapy and reduced overall survival [24?5]. Previous studies [3] assessed the diagnostic performance of each of the above mentioned biomarkers singularly considered in selected case-control comparative surveys. The aim of the present study was to identify a sequential multi-marker panel in cfDNA able to increase the predictive capability in the diagnosis of cutaneous melanoma in comparison with each single marker alone. To this purpose, we tested total cfDNA concentration, cfDNA integrity, BRAFV600E mutation and RASSF1A promoter methylation associated to cfDNA in a series of 76 melanoma patients and 63 healthy controls.Table 1. Clinicopathological characteristics of melanoma cases.Parameter Total Location Head and neck Limbs Chest Acral Genital Thickness In situ #1 mm 1.01?.0 mm 2.01?.0 mm .4 mm Clark Level I II III IV Ulceration Absent.N observed that in patients affected by several neoplastic diseases plasma DNA contains longer fragments than in healthy subjects [4?0] reflected by the increase of DNA integrity index.Cell-Free DNA Biomarkers in MelanomaThe above mentioned parameters can obviously be considered as non-specific biomarkers, since the increase of cfDNA concentration and integrity is common to the large majority of human solid cancers. When cfDNA is used to detect genetic and epigenetic modifications in a specific tumor, it is necessary to select definite molecular targets that are expected to be altered in affected patients. In cutaneous melanoma, the oncogene BRAF is frequently mutated. BRAF is a serine hreonine protein kinase involved in the RAS AF EK RK pathway [11] which regulates cell growth, survival, differentiation and senescence [12]. The oncogene BRAF is frequently mutated in other human cancers constitutively activating the MAPK pathway. The most common BRAF mutation, which accounts for more than 90 of cases of cancer involving this gene, is the T1799A transversion, converting valine to glutamic acid at position 600 (V600E) [13]. BRAF somatic mutations have been reported in 66 of malignant melanomas [13] and are likely to be a crucial step in the initiation of melanocytic neoplasia, as they are found also in melanocytic nevi [14]. BRAF mutations are an attractive target for therapeutic interventions, as they represent an early event in melanoma pathogenesis and are preserved throughout tumor progression [15]. Specific inhibitors of mutant BRAF, such as PLX4032, were developed and tested in clinical trials showing response rates of more than 50 and improved rates of overall and progression-free survival in patients with metastatic melanoma with the BRAFV600E genetic variant [16]. BRAFV600E mutation has been investigated as a marker in cfDNA from melanoma patients by Daniotti et al. [17] and Yancovitz et al. [18]. Finally, it is widely demonstrated that a limited number of genes is epigenetically disregulated in cutaneous melanoma. RASSF1A (Ras association domain family 1 isoform A) is a tumor suppressor gene, which regulates mitosis, cell cycle and apoptosis [19]. It is inactivated mostly by inappropriate promoter methylation in many types of cancers [19]. RASSF1A promoter is methylated in 55 of cutaneous melanomas [20]. Methylation of RASSF1A increases significantly with advanced clinical stage, suggesting that inactivation of this gene is associated with tumor progression [21]. RASSF1A promoter hypermethylation has been detected in cfDNA from melanoma patients [22?3] in association with a worse response to therapy and reduced overall survival [24?5]. Previous studies [3] assessed the diagnostic performance of each of the above mentioned biomarkers singularly considered in selected case-control comparative surveys. The aim of the present study was to identify a sequential multi-marker panel in cfDNA able to increase the predictive capability in the diagnosis of cutaneous melanoma in comparison with each single marker alone. To this purpose, we tested total cfDNA concentration, cfDNA integrity, BRAFV600E mutation and RASSF1A promoter methylation associated to cfDNA in a series of 76 melanoma patients and 63 healthy controls.Table 1. Clinicopathological characteristics of melanoma cases.Parameter Total Location Head and neck Limbs Chest Acral Genital Thickness In situ #1 mm 1.01?.0 mm 2.01?.0 mm .4 mm Clark Level I II III IV Ulceration Absent.

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Author: Squalene Epoxidase