MGMT promoter methylation analysis for allocating combined CCNU/TMZ chemotherapy: Lessons learned from the CeTeG/NOA-09 trial

The CeTeG/NOA-09 trial showed a survival benefit for combined CCNU/TMZ therapy in MGMT-promoter-methylated glioblastoma patients (quantitative methylation-specific PCR [qMSP] ratio > 2). Here, we report on the prognostic value of the MGMT promoter methylation ratio determined by qMSP and evaluate the concordance of MGMT methylation results obtained by qMSP, pyrosequencing (PSQ) or DNA methylation arrays (MGMT-STP27). A potential association of qMSP ratio with survival was analyzed in the CeTeG/NOA-09 trial population (n = 129; log-rank tests, Cox regression analyses). The concordance of MGMT methylation assays (qMSP, PSQ and MGMT-STP27) was evaluated in 76 screened patients. Patients with tumors of qMSP ratio > 4 showed superior survival compared to those with ratios 2-4 (P = .0251, log-rank test). In multivariate analysis, the qMSP ratio was not prognostic across the study cohort (hazard ratio [HR] = 0.88; 95% CI: 0.72-1.08). With different cutoffs for qMSP ratio (4, 9, 12 or 25), the CCNU/TMZ benefit tended to be larger in subgroups with lower ratios (eg, for cutoff 9: HR 0.32 for lower subgroup, 0.73 for higher subgroup). The concordance rates with qMSP were 94.4% (PSQ) and 90.2% (MGMT-STP27). Discordant results were restricted to tumors with qMSP ratios <= 4 and PSQ mean methylation rate <= 25%. Despite a shorter survival in MGMT-promoter-methylated patients with lower methylation according to qMSP, these patients had a benefit from combined CCNU/TMZ therapy, which even tended to be stronger than in patients with higher methylation rates. With acceptable concordance rates, decisions on CCNU/TMZ therapy may also be based on PSQ or MGMT-STP27

Cytokine networks in neuroinflammation

Cytokines provide cells with the ability to communicate with one another and orchestrate complex multicellular behaviour. There is an emerging understanding of the role that cytokines play in normal homeostatic tissue function and how dysregulation of these cytokine networks is associated with pathological conditions. The central nervous system (CNS), where few blood-borne immune cells circulate, seems to be particularly vulnerable to dysregulated cytokine networks. In degenerative diseases, such as proteopathies, CNS-resident cells are the predominant producers of pro-inflammatory cytokines. By contrast, in classical neuroinflammatory diseases, such as multiple sclerosis and encephalitides, pro-inflammatory cytokines are mainly produced by tissue-invading leukocytes. Whereas the effect of dysregulated cytokine networks in proteopathies is controversial, cytokines delivered to the CNS by invading immune cells are in general detrimental to the tissue. Here, we summarize recent observations on the impact of dysregulated cytokine networks in neuroinflammation