title: Relationship between hypermethylated MGMT gene and osteosarcoma necrosis rate after chemotherapy.
abstract: To investigate the relativity of MGMT(O-6-methylguanine-DNA methyltransferase) gene methylation from patients with protein expression and osteosarcoma necrosis rate after chemotherapy. Fifty-one oteosarcoma tissues were collected, Methylation of MGMT gene promoter was detected by methylation-specific PCR method, and protein expression of MGMT was examined by immunohistochemistry procedure, the relationship between methylated MGMT gene expression and patients response to chemotherapy was analyzed. The positive ratio of methylation MGMT gene promoter in 51 patients was 23.5% (12 in 51). Negative percentage of protein expression of MGMT was 27.5% (14 in 51). It seemed that methylation of MGMT gene in osteosarcoma tissues had no evident relationship with the patient's age, sexuality, and the size and type of neoplasms, etc. The necrosis rates of methylated MGMT of osteosarcoma (tumor grade from I to IV) were 0 (0/51), 3.9% (2/51), 5.9% (3/51), 13.7% (7/51), respectively. In contrast, the necrosis rates of unmethylated MGMT of osteosarcoma (tumor grade from I to IV) were 45.1% (23/51), 25.5% (13/51), 3.9% (2/51), 2.0% (1/51), respectively. It suggest that methylated and unmethylated MGMT gene of osteosarcoma have significant difference in protein expression. The unmethylated MGMT gene has higher positive protein expression (u = -4.92, P < 0.001). Methylation of MGMT gene has higher tumor necrosis rate in osteosarcoma patients. Methylation in MGMT promoter may be important for judging the effect of chemotherapy in Osteosarcoma patients.
authors.affiliation: Department of Orthopedics, the Affiliated Hospital of Academy of Military Medical Sciences, PLA 307th Hospital, Beijing, 100071, China.
authors.forename: Qiu
authors.initials: Q
authors.lastname: Cui
authors.forename: Weihao
authors.initials: W
authors.lastname: Jiang
authors.forename: Jun
authors.initials: J
authors.lastname: Guo
authors.forename: Cheng
authors.initials: C
authors.lastname: Liu
authors.forename: Dingfeng
authors.initials: D
authors.lastname: Li
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Wang
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Zeng
mesh_terms: D000293:Adolescent; D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001859:Bone Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology*; D002648:Child; D002945:Cisplatin / Q000008:administration & dosage; D019175:DNA Methylation / Q000187:drug effects*; D015254:DNA Modification Methylases / Q000235:genetics* / Q000378:metabolism; D045643:DNA Repair Enzymes / Q000235:genetics* / Q000378:metabolism; D004273:DNA, Neoplasm / Q000235:genetics; D004317:Doxorubicin / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007069:Ifosfamide / Q000008:administration & dosage; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D009336:Necrosis; D012516:Osteosarcoma / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology*; D011379:Prognosis; D025521:Tumor Suppressor Proteins / Q000235:genetics* / Q000378:metabolism; D055815:Young Adult
chemical_list: D004273:DNA, Neoplasm; D025521:Tumor Suppressor Proteins; D004317:Doxorubicin; D015254:DNA Modification Methylases; C515491:MGMT protein, human; D045643:DNA Repair Enzymes; D002945:Cisplatin; D007069:Ifosfamide