title: Loss of heterozygosity of a locus in the chromosomal region 17p13.3 is associated with increased cell proliferation in astrocytic tumors.
abstract: We had previously reported that loss of heterozygosity (LOH) of the D17S379 locus on 17p13.3 was significantly more frequent in high-grade gliomas (anaplastic astrocytoma, AA; glioblastoma multiforme, GBM) than in those of a low-grade diffuse astrocytoma (DA); however, this was independent of alterations at the TP53 locus, We also showed that LOH of D17S379 was associated with positive staining for p53 protein on immunohistochemistry, but LOH of the TP53 gene had no such association. In this work we show that cell proliferation as determined by MIB-1 labeling index (LI) was significantly higher in tumors with LOH of D17S379 than those with no LOH (NLOH). In accord with our previous results, p53 protein immunopositivity was also associated with increased MIB-1 LI; however, we observed no such association of LI with TP53 LOH. The results further confirm that alteration of one or more putative tumor suppressor loci at 17p13.3 is associated with increased proliferation in astrocytic tumors.
authors.affiliation: Department of Pathology, All India Institute of Medical Sciences, 110029, New Delhi, India. sarkarcs@hotmail.com
authors.forename: Chitra
authors.initials: C
authors.lastname: Sarkar
authors.forename: Parthaprasad
authors.initials: P
authors.lastname: Chattopadhyay
authors.forename: Angela Mercy
authors.initials: AM
authors.lastname: Ralte
authors.forename: Ashok K
authors.initials: AK
authors.lastname: Mahapatra
authors.forename: Subrata
authors.initials: S
authors.lastname: Sinha
mesh_terms: D000328:Adult; D000367:Age Factors; D001254:Astrocytoma / Q000235:genetics* / Q000473:pathology; D002455:Cell Division; D002886:Chromosomes, Human, Pair 17; D016158:Genes, p53; D006801:Humans; D019394:Ki-67 Antigen / Q000032:analysis; D019656:Loss of Heterozygosity; D008875:Middle Aged; D009154:Mutation
chemical_list: D019394:Ki-67 Antigen