TY - JOUR
T1 - Overexpression and amplification of c-myc in the Syrian hamster kidney during estrogen carcinogenesis
T2 - A probable critical role in neoplastic transformation
AU - Li, Jonathan J.
AU - Hou, Xiaoying
AU - Banerjee, Sushanta K.
AU - Liao, De Zhong Joshua
AU - Maggouta, Frederiki
AU - Norris, James S.
AU - Li, Sara Antonia
PY - 1999/5/15
Y1 - 1999/5/15
N2 - An estrogen receptor-driven, multistep process for estrogen carcinogenesis in the Syrian hamster kidney is proposed. Because in this species the reproductive and urogenital tracts arise from the same embryonic germinal ridge, it is evident that the kidney has carried over genes that are responsive to estrogens. Using in situ hybridization, overexpression of early estrogen-response genes, i.e., c-myc and c-fos, has been shown to be localized preferentially in early renal tumor foci after 3.5-4.0 months of estrogen treatment. This event coincides with an increased number of S-phase proliferating cell nuclear antigen-labeled cells in these tumor foci, along with a rapid rise in aneuploid frequency in the kidney. Western blot analyses of c-MYC and c-FOS protein products support the overexpression of these genes. Amplification of c-myc, 2.4-3.6-fold, but not of c-fos, was detected in 67% of the primary renal tumors examined, by Southern blot analyses. Consistent chromosomal gains, common to both diethylstilbestrol- and estradiol-induced renal neoplasms, were observed in chromosomes 1, 2, 3, (6), 11, (13), 16, 20, and 21 (chromosome number alterations are indicated in parentheses). Using fluorescence in situ hybridization, the c-myc gene was localized to hamster chromosome 6qb. Chromosome 6 exhibited a high frequency of trisomies and tetrasomies in the kidney after 5.0 months of estrogen treatment and in primary renal tumors. The data presented indicate that estrogen-induced genomic instability may be a key element in carcinogenic processes induced by estrogens.
AB - An estrogen receptor-driven, multistep process for estrogen carcinogenesis in the Syrian hamster kidney is proposed. Because in this species the reproductive and urogenital tracts arise from the same embryonic germinal ridge, it is evident that the kidney has carried over genes that are responsive to estrogens. Using in situ hybridization, overexpression of early estrogen-response genes, i.e., c-myc and c-fos, has been shown to be localized preferentially in early renal tumor foci after 3.5-4.0 months of estrogen treatment. This event coincides with an increased number of S-phase proliferating cell nuclear antigen-labeled cells in these tumor foci, along with a rapid rise in aneuploid frequency in the kidney. Western blot analyses of c-MYC and c-FOS protein products support the overexpression of these genes. Amplification of c-myc, 2.4-3.6-fold, but not of c-fos, was detected in 67% of the primary renal tumors examined, by Southern blot analyses. Consistent chromosomal gains, common to both diethylstilbestrol- and estradiol-induced renal neoplasms, were observed in chromosomes 1, 2, 3, (6), 11, (13), 16, 20, and 21 (chromosome number alterations are indicated in parentheses). Using fluorescence in situ hybridization, the c-myc gene was localized to hamster chromosome 6qb. Chromosome 6 exhibited a high frequency of trisomies and tetrasomies in the kidney after 5.0 months of estrogen treatment and in primary renal tumors. The data presented indicate that estrogen-induced genomic instability may be a key element in carcinogenic processes induced by estrogens.
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M3 - Article
C2 - 10344741
AN - SCOPUS:0033563246
SN - 0008-5472
VL - 59
SP - 2340
EP - 2346
JO - Cancer Research
JF - Cancer Research
IS - 10
ER -