title: Allelic imbalance of 12q22-23 associated with APAF-1 locus correlates with poor disease outcome in cutaneous melanoma.
abstract: Cutaneous melanoma is a highly aggressive tumor that is relatively resistant to chemotherapy and radiotherapy. This resistance may be in part due to inhibition of apoptosis. Apoptotic protease activating factor-1(APAF-1), a candidate tumor suppressor gene, mediates p53-induced apoptosis, and its loss promotes oncogenic transformation. To determine whether loss of the APAF-1 locus influences tumor progression, we assessed loss of heterozygosity microsatellites on the APAF-1 locus (12q22-23) in 62 primary and 112 metastatic melanomas. We discovered that frequency of allelic imbalance was significantly higher in metastatic tumors (n = 36 of 98; 37%) than in primary melanomas (n = 10 of 54; 19%; P = 0.02). In metastatic melanomas, APAF-1 loss significantly correlated with a worse prognosis (P < 0.05) in the patients, and its loss during melanoma tumor progression suggests that APAF-1 is a tumor suppressor gene. Furthermore, loss of heterozygosity was frequent in the 12q22-23 chromosome region centromeric to the APAF-1 locus suggesting that other tumor-related genes may be present in the 12q22-23 region. In summary, the study demonstrates that allelic imbalance in the 12q22-23 region is a genomic surrogate of poor disease outcome for cutaneous melanoma patients.
authors.affiliation: Department of Molecular Oncology, John Wayne Cancer Institute, Saint John's Health Center, 2200 Santa Monica Boulevard, Santa Monica, CA 90404, USA.
authors.forename: Akihide
authors.initials: A
authors.lastname: Fujimoto
authors.forename: Hiroya
authors.initials: H
authors.lastname: Takeuchi
authors.forename: Bret
authors.initials: B
authors.lastname: Taback
authors.forename: Eddy C
authors.initials: EC
authors.lastname: Hsueh
authors.forename: David
authors.initials: D
authors.lastname: Elashoff
authors.forename: Donald L
authors.initials: DL
authors.lastname: Morton
authors.forename: Dave S B
authors.initials: DS
authors.lastname: Hoon
mesh_terms: D017209:Apoptosis; D053477:Apoptotic Protease-Activating Factor 1; D002881:Chromosomes, Human, Pair 12; D019175:DNA Methylation; D004273:DNA, Neoplasm / Q000235:genetics; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D019656:Loss of Heterozygosity; D008297:Male; D008545:Melanoma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D018895:Microsatellite Repeats; D008875:Middle Aged; D011401:Promoter Regions, Genetic; D011506:Proteins / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D012334:RNA, Neoplasm / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012878:Skin Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D015996:Survival Rate
chemical_list: C506592:APAF1 protein, human; D053477:Apoptotic Protease-Activating Factor 1; D004273:DNA, Neoplasm; D011506:Proteins; D012333:RNA, Messenger; D012334:RNA, Neoplasm