Methylation of O<sup>6</sup>-Methyl Guanine Methyltransferase Gene Promoter in Meningiomas - Comparison between Tumor Grades I, II, and III

Larijani, Leila; Madjd, Zahra; Samadikuchaksaraei, Alí; Younespour, Shima; Zham, Hanieh; Rakhshan, Azadeh; Mohammadi, F; Rahbari, Ali; Moradi, Abdolvahab

doi:10.7314/apjcp.2014.15.1.33

Cited by 18 publications

(10 citation statements)

References 38 publications

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“…Of the 39 mixed-population studies, 21 were conducted in Tehran province [39–41, 43, 45–46, 48–49, 51–54, 59–61, 64–66, 72–73, 75], specifically at Tehran University of Medical Sciences (n = 16) [39–41, 43, 45–46, 48–49, 51, 59–61, 65–66, 73, 75] or Shahid Beheshti University of Medical Sciences (n = 5) [52–54, 64, 72]. The study objectives were categorized as genetic (n = 9 articles [38, 44, 50, 56, 62, 65–66, 70–71], 449 patients), epidemiologic (n = 7 articles [47, 49, 60–61, 63, 69, 74], 13,193 patients), pathologic (n = 7 articles [46, 48, 52, 55, 67–68, 72], 4,365 patients), clinical (n = 6 articles [39, 41, 43, 45, 57, 76], 393 patients), radiologic (n = 4 articles [, 86 patients), radiotherapy (n = 3 articles [54, 58–59, 73], 54 patients), surgical (n = 2 articles [42, 51], 44 patients), or virologic [75] (n = 1, 58 patients).…”

Section: Resultsmentioning

confidence: 99%

“…The study objectives were categorized as genetic (n = 9 articles [38, 44, 50, 56, 62, 65–66, 70–71], 449 patients), epidemiologic (n = 7 articles [47, 49, 60–61, 63, 69, 74], 13,193 patients), pathologic (n = 7 articles [46, 48, 52, 55, 67–68, 72], 4,365 patients), clinical (n = 6 articles [39, 41, 43, 45, 57, 76], 393 patients), radiologic (n = 4 articles [, 86 patients), radiotherapy (n = 3 articles [54, 58–59, 73], 54 patients), surgical (n = 2 articles [42, 51], 44 patients), or virologic [75] (n = 1, 58 patients).…”

Section: Resultsmentioning

confidence: 99%

“…PSI was evaluated in only one study [41], which was reported in 2004. Seven articles described the follow-up of patients [41, 51, 53, 57, 64–65, 75]. …”

Section: Resultsmentioning

confidence: 99%

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Comprehensive analysis of Iranian reports of pediatric central nervous system tumors

Mehrvar

Akbari

et al. 2017

Childs Nerv Syst

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Purpose Iran lacks a national registry reporting the data of central nervous system (CNS) tumors in children. Consequently, treatment success and failure rates are unknown, and a centralized system for disease-management recommendations does not exist. Methods To critically evaluate the current state of pediatric CNS tumor studies and reporting in Iran, we performed an extensive retrospective analysis of all known reports identified with multiple search engines. Results Of 409 initially retrieved articles, we evaluated 123 matching our inclusion criteria. We further narrowed these reports to 74 by excluding studies pertaining to adult patients only, non-CNS tumors, or brain metastases. We also excluded studies that were performed outside of Iran or that did not contain relevant data from our analysis. We divided the remaining studies into those describing exclusively pediatric patients (3,484 patients) and those describing mixed populations of adults and children (18,641 patients). In total, our analysis included 22,125 patients. Conclusions We identified many limitations in the reporting of studies describing the treatment or prevalence of CNS tumors in children in Iran. Our results may guide future efforts in Iran to improve the care for children with CNS tumors and may provide a valuable template for other comprehensive country- and disease-specific retrospective analyses.

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Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

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Comprehensive analysis of Iranian reports of pediatric central nervous system tumors

Mehrvar

Akbari

et al. 2017

Childs Nerv Syst

View full text Add to dashboard Cite

show abstract

“…In the past, several studies focused on investigating promoter methylation mainly using a targeted approach for a limited number of genes [4,6–8,11,30,14,15,34,38,47]. With time, molecular advances allowed interrogation at a larger number of CpG loci [35] culminating with the methylation assays from Illumina (27k and 450k) interrogating approximately 27.000 and 450.000 CpG loci [74,21].…”

Section: Discussionmentioning

confidence: 99%

Global epigenetic profiling identifies methylation subgroups associated with recurrence-free survival in meningioma

Olar

Wani

Wilson³

et al. 2017

Acta Neuropathol

157

118

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Meningioma is the most common primary brain tumor and carries a substantial risk of local recurrence. Methylation profiles of meningioma and their clinical implications are not well understood. We hypothesized that aggressive meningiomas have unique DNA methylation patterns that could be used to better stratify patient management. Samples (n=140) were profiled using the Illumina HumanMethylation450 BeadChip. Unsupervised modeling on a training set (n=89) identified 2 molecular methylation subgroups of meningioma (MM) with significantly different recurrence free survival (RFS) times between the groups: a prognostically unfavorable subgroup (MM-UNFAV) and a prognostically favorable subgroup (MM-FAV). This finding was validated in the remaining 51 samples and led to a baseline meningioma methylation classifier (bMMC) defined by 283 CpG loci (283-bMMC). To further optimize a recurrence predictor, probes subsumed within the baseline classifier were subject to additional modeling using a similar training/validation approach, leading to a 64-CpG loci meningioma methylation predictor (64-MMP). After adjustment for relevant clinical variables [WHO grade, mitotic index, Simpson grade, sex, location, and copy number aberrations (CNA)] multivariable analyses for RFS showed that the baseline methylation classifier was not significant (p=0.0793). The methylation predictor however was significantly associated with tumor recurrence (p<0.0001). CNA were extracted from the 450k intensity profiles. Tumor samples in the MM-UNFAV subgroup showed an overall higher proportion of CNAs compared to the MM-FAV subgroup tumors and the CNAs were complex in nature. CNAs in the MM-UNFAV subgroup included recurrent losses of 1p, 6q, 14q and 18q, and gain of 1q, all of which were previously identified as indicators of poor outcome. In conclusion, our analyses demonstrate robust DNA methylation signatures in meningioma that correlate with CNAs and stratify patients by recurrence risk.

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“…MGMT (O6-methyl gyuanine methyl transferase) is an important DNA repair enzyme which specifically repairs the DNA adducts caused by alkylating agents like nitrosamines (Du et al, 2013). It specifically removes the alkyl group from the O6 position of guanine residue by transferring it to specific cytosine residue within the MGMT protein itself (Larijani et al, 2014). Impaired activity of the DNA repair enzyme MGMT may result in impaired DNA repairing capacity thereby resulting in accumulation of damaged DNA causing tumor growth.…”

Section: Introductionmentioning

confidence: 99%

Promoter Methylation of MGMT Gene in Serum of Patients with Esophageal Squamous Cell Carcinoma in North East India

Das

Sharma²,

Sekhon³

et al. 2014

Asian Pacific Journal of Cancer Prevention

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Methylation of O⁶-Methyl Guanine Methyltransferase Gene Promoter in Meningiomas - Comparison between Tumor Grades I, II, and III

Cited by 18 publications

References 38 publications

Comprehensive analysis of Iranian reports of pediatric central nervous system tumors

Comprehensive analysis of Iranian reports of pediatric central nervous system tumors

Global epigenetic profiling identifies methylation subgroups associated with recurrence-free survival in meningioma

Promoter Methylation of MGMT Gene in Serum of Patients with Esophageal Squamous Cell Carcinoma in North East India

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Methylation of O6-Methyl Guanine Methyltransferase Gene Promoter in Meningiomas - Comparison between Tumor Grades I, II, and III

Cited by 18 publications

References 38 publications

Comprehensive analysis of Iranian reports of pediatric central nervous system tumors

Comprehensive analysis of Iranian reports of pediatric central nervous system tumors

Global epigenetic profiling identifies methylation subgroups associated with recurrence-free survival in meningioma

Promoter Methylation of MGMT Gene in Serum of Patients with Esophageal Squamous Cell Carcinoma in North East India

Contact Info

Product

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Methylation of O⁶-Methyl Guanine Methyltransferase Gene Promoter in Meningiomas - Comparison between Tumor Grades I, II, and III