mortality/aging
• some mice die between 9 and 18 months of age; these mice have no evidence of tumors but have severe extramedullary hematopoiesis
|
immune system
• lymphocytes exhibit increased proliferation upon mitogenic stimulation
|
• increase in levels of mature B cells in spleen and lymph nodes
|
• enlarged marginal zones
|
• reactive lymph nodes characterized by prominent secondary follicles
|
• enlarged germinal centers
|
• mutants exhibit lymphoproliferative disorders
|
neoplasm
• 8.2% incidence of tumors
• however, mutants do not show increased incidence of chemically-induced tumors
|
• adenocarcinomas of the lung and pancreas
|
• 73% of tumors are of connective tissue origin, including angiosarcomas and skin fibrosarcoma
|
hematopoietic system
• in the spleen
|
• lymphocytes exhibit increased proliferation upon mitogenic stimulation
|
• increase in levels of mature B cells in spleen and lymph nodes
|
• enlarged marginal zones
|
cellular
• MEFs are susceptible to ras oncogenic transformation
|
• MEFs exhibit a higher proliferation rate and plating efficiency than wild-type MEFs
• serum starved MEFs re-enter the cell cycle more efficiently than wild-type MEFs
|
growth/size/body