PA 31. Examination OF MGMT METHYLATION AND Long run SURVIVAL IN Patients WITH GLIOBLASTOMA MULTIFORME Zita A. Sibenaller, Carey L. Allen, Craig J. Kilburg, and Timothy C. Ryken, University of Iowa Carver School of Medicine, Iowa City, IA, USA Tumorigenesis is established not merely from the DNA sequence of precise genes but in addition from the epigenetic code that regulates their expression. 1 way that expression of genes is epigenetically regulated is by means of DNA methylation, particularly while in the promoter region. It’s been reported the MGMT promoter is methylated in about 40% of grade III and IV glioma tissue, which prevents transcription on the gene. The loss with the MGMT protein results during the cells inability to fix alkylation adducts while in the DNA, culminating in cell death. Also reported is known as a survival advantage for individuals taken care of with an alkylating agent and radiotherapy in which the MGMT gene is inactivated.
There exists an ongoing debate as on the greater representation from the epigenetic code, tissue samples created up of different cell varieties, or cell lines established from your tumor tissue containing 1 cell variety, grown in vitro, that might have undergone a modify during the epigenetic tags. Applying microarray engineering, we examined MGMT expression in twenty key cell lines established from sufferers i was reading this diagnosed with glioblastoma KW-2449 multiforme. Even though MGMT expression varied involving each sample, our data identified a patient group with an common ten fold lessen in MGMT gene expression. Every patient received BCNU wafers and an alkylating agent in the time of their first surgical procedure and the normal program of follow up therapy, but their prognosis was poor. Whilst the sample dimension was minor, the information propose that the result of MGMT methylation may well be separate from that of alkylating agents.
PA 32. INTRAOPERATIVE STAGING FOR POSTERIOR FOSSA BRAIN TUMORS M. M. Souweidane,1 I. J. Dunkel,two M. A. Edgar,three M. Manaqibwala,four Paul J. Christos,five L. Becker,6 and J. T. Rutka7, one,5The Weill Healthcare School of Cornell University, New york, NY, USA, 1,two,3Memorial Sloan Kettering Cancer Center, Ny, NY, USA, 4Robert Wood Johnson Healthcare College, New Brunswick, NJ, USA, six,7Hospital for Sick Kids, Toronto, Canada Cerebrospinal fluid and arachnoid sampling in the course of tumor resec tion may perhaps provide prognostic information and facts. CSF and arachnoid tissue had been sampled at the time of major posterior fossa tumor resection. The results have been tabulated by tumor variety. Sufferers have been assigned to group A or group B. The outcomes of intraoperative staging for group A patients have been in contrast with typical staging techniques and analyzed with respect to illness end result. From a cohort of 73 patients, 67 individuals had CSF, 69 had arachnoid, and 63 had each sampled.