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Phenotypes Associated with This Genotype
Genotype
MGI:5432250
Allelic
Composition
Tg(MMTV-rtTA)1Lach/0
Tg(tetO-MYC)1Lach/0
Genetic
Background
involves: FVB
Find Mice Using the International Mouse Strain Resource (IMSR)
No mouse lines available in IMSR.
See publication links below for author information.
phenotype observed in females
phenotype observed in males
N normal phenotype
neoplasm
• chronically doxycycline induced females develop mammary tumors with high penetrance (86%) following an average of 22 weeks of induction (J:67498)
• mice fed doxycycline after weaning develop solitary mammary tumors with a median latency of 26 weeks after induction (J:133578)
• mammary tumors in chronically doxycycline induced females are invasive mammary adenocarcinomas
• withdrawal of doxycycline from chronically induced tumor-bearing mutants results in rapid regression of a subset of invasive mammary adenocarcinomas (14 days) but another subset of tumors decrease in size but then resume growth
• tumors that continue to grow after doxycycline removal show undetectable expression of the MYC transgene but increased endogenous Myc expression and exhibit mutations in Kras or Nras

integument
• mammary epithelium of mutants induced with doxycycline exhibits increased proliferation
• mammary glands of mutants induced with doxycycline for 4 months exhibit atypical lobuloalveolar growths (dysplasia)
• non-tumor bearing mammary glands of mutants induced with doxycycline for 30 weeks (chronically induced) exhibit numerous epithelial hyperplasts and dysplasts, however when doxycycline is withdrawn for 12 weeks, most epithelial ducts appear normal
• chronically doxycycline induced females develop mammary tumors with high penetrance (86%) following an average of 22 weeks of induction (J:67498)
• mice fed doxycycline after weaning develop solitary mammary tumors with a median latency of 26 weeks after induction (J:133578)
• mammary tumors in chronically doxycycline induced females are invasive mammary adenocarcinomas
• withdrawal of doxycycline from chronically induced tumor-bearing mutants results in rapid regression of a subset of invasive mammary adenocarcinomas (14 days) but another subset of tumors decrease in size but then resume growth
• tumors that continue to grow after doxycycline removal show undetectable expression of the MYC transgene but increased endogenous Myc expression and exhibit mutations in Kras or Nras
• mammary glands of mutants induced with doxycycline for 30 days are hyperplastic
• mammary glands of mutants induced with doxycycline for 4 months exhibit focal hyperplasia
• mammary epithelium of mutants induced with doxycycline exhibits increased apoptosis

endocrine/exocrine glands
• mammary epithelium of mutants induced with doxycycline exhibits increased proliferation
• mammary glands of mutants induced with doxycycline for 4 months exhibit atypical lobuloalveolar growths (dysplasia)
• non-tumor bearing mammary glands of mutants induced with doxycycline for 30 weeks (chronically induced) exhibit numerous epithelial hyperplasts and dysplasts, however when doxycycline is withdrawn for 12 weeks, most epithelial ducts appear normal
• chronically doxycycline induced females develop mammary tumors with high penetrance (86%) following an average of 22 weeks of induction (J:67498)
• mice fed doxycycline after weaning develop solitary mammary tumors with a median latency of 26 weeks after induction (J:133578)
• mammary tumors in chronically doxycycline induced females are invasive mammary adenocarcinomas
• withdrawal of doxycycline from chronically induced tumor-bearing mutants results in rapid regression of a subset of invasive mammary adenocarcinomas (14 days) but another subset of tumors decrease in size but then resume growth
• tumors that continue to grow after doxycycline removal show undetectable expression of the MYC transgene but increased endogenous Myc expression and exhibit mutations in Kras or Nras
• mammary glands of mutants induced with doxycycline for 30 days are hyperplastic
• mammary glands of mutants induced with doxycycline for 4 months exhibit focal hyperplasia
• mammary epithelium of mutants induced with doxycycline exhibits increased apoptosis

cellular
• mammary epithelium of mutants induced with doxycycline exhibits increased proliferation

Mouse Models of Human Disease
DO ID OMIM ID(s) Ref(s)
breast cancer DOID:1612 OMIM:114480
J:67498 , J:133578


Contributing Projects:
Mouse Genome Database (MGD), Gene Expression Database (GXD), Mouse Models of Human Cancer database (MMHCdb) (formerly Mouse Tumor Biology (MTB)), Gene Ontology (GO)
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last database update
03/19/2024
MGI 6.23
The Jackson Laboratory