After the administration of TMZ concomitant with and adjuvant to RT in patients with GBM, the pattern of, and time to, recurrence are strictly correlated with MGMT methylation status.
BackgroundOral squamous cell carcinoma (OSCC) is usually diagnosed at an advanced stage and is commonly preceded by oral premalignant lesions. The mortality rates have remained unchanged (50% within 5 years after diagnosis), and it is related to tobacco smoking and alcohol intake. Novel molecular markers for early diagnosis are urgently needed. The purpose of this study was to evaluate the diagnostic value of methylation level in a set of 18 genes by bisulfite next-generation sequencing.MethodsWith minimally invasive oral brushing, 28 consecutive OSCC, one squamous cell carcinoma with sarcomatoid features, six high-grade squamous intraepithelial lesions (HGSIL), 30 normal contralateral mucosa from the same patients, and 65 healthy donors were evaluated for DNA methylation analyzing 18 target genes by quantitative bisulfite next-generation sequencing. We further evaluated an independent cohort (validation dataset) made of 20 normal donors, one oral fibroma, 14 oral lichen planus (OLP), three proliferative verrucous leukoplakia (PVL), and two OSCC.ResultsComparing OSCC with normal healthy donors and contralateral mucosa in 355 CpGs, we identified the following epigenetically altered genes: ZAP70, ITGA4, KIF1A, PARP15, EPHX3, NTM, LRRTM1, FLI1, MIR193, LINC00599, PAX1, and MIR137HG showing hypermethylation and MIR296, TERT, and GP1BB showing hypomethylation. The behavior of ZAP70, GP1BB, H19, EPHX3, and MIR193 fluctuated among different interrogated CpGs. The gap between normal and OSCC samples remained mostly the same (Kruskal-Wallis P values < 0.05), but the absolute values changed conspicuously. ROC curve analysis identified the most informative CpGs, and we correctly stratified OSCC and HGSIL from normal donors using a multiclass linear discriminant analysis in a 13-gene panel (AUC 0.981). Only the OSCC with sarcomatoid features was negative. Three contralateral mucosa were positive, a sign of a possible field cancerization. Among imprinted genes, only MIR296 showed loss of imprinting. DNMT1, TERC, and H19 together with the global methylation of long interspersed element 1 were unchanged. In the validation dataset, values over the threshold were detected in 2/2 OSCC, in 3/3 PVL, and in 2/14 OLP.ConclusionsOur data highlight the importance of CpG location and correct estimation of DNA methylation level for highly accurate early diagnosis of OSCC.Electronic supplementary materialThe online version of this article (doi:10.1186/s13148-017-0386-7) contains supplementary material, which is available to authorized users.
To evaluate the effect of adjuvant chemotherapy in patients with local-regional nasopharyngeal carcinoma (NPC) (squamous or undifferentiated) in complete remission at the end of curative radiotherapy (RT) 229 patients were randomized from 1979 to 1983 in a multicenter study to no further therapy (116 patients) or a combination of vincristine, cyclophosphamide, and Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH) (VCA) for six monthly cycles (113 patients). The RT and RT + VCA groups were well balanced for median age (50 v 49 years), histology (undifferentiated carcinoma, 73% v 70%), tumor extent (tumor limited to nasopharynx, 57% v 57%), and nodal extent (negative nodes 26% v 24%, nodes in the lower cervical levels, 17% v 16%). RT was delivered to the nasopharynx, the base of the skull, and bilateral cervical nodes using a split course technique over 10 weeks up to the dose of 60 to 70 Gy in involved sites and 50 Gy to negative nodes. Response to RT was evaluated within 65 days post-RT treatment. Analysis at 48 months did not show significant difference between the two treatment groups in terms of relapse-free survival (RT, 55.8%, RT + VCA, 57.7%, P = .45) and overall survival (RT, 67.3%, RT + VCA, 58.5%, P = .13). The pattern of relapse was similar in the two treatment arms. Distant metastases were the cause of treatment failure in about 50% of relapsing patients. Although the results of the present study did not show any benefit from VCA administered after curative RT, combined systemic chemotherapy should be further explored due to the high incidence of local and distant failure after intensive RT.
O(6)-methylguanine DNA-methyltransferase (MGMT) promoter methylation status is a prognostic factor in newly diagnosed glioblastoma patients. However, it is not yet clear whether, and if so how, MGMT methylation status may change. Moreover, it is unknown whether the prognostic role of this epigenetic feature is retained during the disease course. A retrospective analysis was made using a database of 614 glioblastoma patients treated prospectively from January 2000 to August 2008. We evaluated only patients who met the following inclusion criteria: age > or = 18 years; performance status 0-2; histological diagnosis of glioblastoma at both first and second surgery for recurrence; postoperative treatment consisting of: (i) radiotherapy (RT) followed by adjuvant temozolomide (TMZ) until 2005 and (ii) TMZ concurrent with and adjuvant to RT after 2005; a time interval > or = 3 months between first and second surgery. MGMT status was evaluated at first and second surgery in all 44 patients (M:F 32:12, median age: 49 years, range: 27-67 years). In 38 patients (86.4%), MGMT promoter status was assessable at both first and second surgery. MGMT methylation status, changed in 14 patients (37%) of second surgery samples and more frequently in methylated than in unmethylated patients (61.5% vs 24%, P = .03). The median survival was significantly influenced only by MGMT methylation status determined at first surgery (P = .04). Significant changes in MGMT methylation status during the course of GBM occur more frequently in MGMT methylated than unmethylated cases. MGMT methylation status determined at first surgery appears to be of prognostic value; however, it is not predictive of outcome following second surgery.
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