Predominant p53 G→A Transition Mutation and Enhanced Cell Proliferation in Uterine Sarcomas of CBA Mice Treated with 1,2-Dimethylhydrazine

Abstract

A B S T R A~Mouse uterine tumors were examined for genetic alterations in the rus proto-oncogene and p53 tumor suppressor gene and for other biologically relevant immunohistochemical markers that may increase our understanding of the events that occur in uterine cancer. Fourteen dimethylhydrazine (DMH)-induced uterine sarcomas, including 3 primary malignant fibrous histiocytomas (MFH). 7 transplanted MFH, 3 stroinal sarcomas, and 1 undifferenthed sarcoma; were first screened by immunohistochemistry for p53 missense mutations, followed by single strand conformation polymorphism analysis and DNA sequencing for the identification of point mutations. There was 1 0 0 8 correlation between p53 protein immunopositivity and subsequent detection of p53 mutations in DMH-induced malignant fibrous histiocytomas. All M R I had a characteristic p53 G:C+A:T transition mutation. consistent with 06-methylguanine mispairing with thymine, the most common DNA lesion caused by alkylating agents. DMH-induced uterine MFH with p53 mutations also had a higher proliferative rate (qualitatively evaluated by immunohistochemical detection of proliferating cell nuclear antigen) when compared with other DMH-induced sarcomas. Uterine sarcomas were further evaluated for biological end points, such as estrogen receptor and desmin. Neoplastic cells from stromal sarcomas (SS), undifferentiated sarcomas (US), and MFH did not stain for desmin.The estrogen receptor was detected in normal uteri and a small portion of MFH, SS, and US. Our data suggest that DIMH-induced uterine sarcomas are not consistent with smooth muscle cell origin and that a subset of these tumors, specifically DIMH-induced malignant fibrous histiocytomas, have unique p53 G:C-tA:T transitions and a high proliferative rate.

Mechanisms of oral carcinogenesis induced by dibenzo[a,l]pyrene: An environmental pollutant and a tobacco smoke constituent

“…A total of five frozen tumor tissues were homogenized and the isolation of DNA was carried out using a Qiagen genomic DNA isolation procedure as previously described . Amplification of evolutionary conserved exons 5–8 of p53 by PCR was conducted with the primers and conditions reported in literatures: denaturation at 94°C for 60 sec, followed by 35 cycles of amplification (30 sec at 94°C, 60 sec at 71°C for exons 5, 7, and 8; 60 sec at 70°C for exon 6) and an additional extension (70°C or 71°C for 5 min). PCR products were purified with QIAquick PCR purification kit and subjected to direct DNA sequencing on ABI 3130XL capillary sequencer.…”

“…The model may also serve to evaluate the chemopreventive efficacy of agents, which modulate critical molecular mediators such as p53 or COX-2 involved in oral carcinogenesis. (25). After washing, the slides were incubated with 1:50 dilution of the rabbit polyclonal primary antibody, p53 (CM5, Novocastra) or COX-2 (Cayman) for 30 min at room temperature, incubated with Dako Envision 1TM anti-rabbit labeled polymer conjugated with HRP for 20 min at room temperature, developed using Dako DAB 1TM , and counterstained with Meyer's modified hematoxylin.…”

Hemangiosarcoma in Mice Administered Pregabalin: Analysis of Genotoxicity, Tumor Incidence, and Tumor Genetics

“…to produce these mutation patterns (Basu et al, 1989;Cooke et al, 2003;Firestein et al, 1997;Rossman and Goncharova, 1998;Souici et al, 2000;Trukhanova et al, 1998). That these mutations arose through endogenous mechanisms is further supported by pregabalin's lack of activity in an extensive battery of genetic toxicity assays.…”

Genetic alterations in K‐ras and p53 cancer genes in lung neoplasms from Swiss (CD‐1) male mice exposed transplacentally to AZT

“…DNA was isolated and extracted from these tumor-bearing sections and amplified by PCR. Details of the use of nested primers for K-ras and p53 genes have been described previously [Hegi et al, 1993;Sills et al, 1995;Trukhanova et al, 1998]. Positive controls for K-ras and p53 mutations and controls lacking DNA were run with all sets of reactions.…”