Laboratory) were maintained in AALAC-accredited facilities and all procedures
approved by the Institutional Animal Care and Use Committee (IACUC) at the
University of Pennsylvania (Philadelphia, PA). To propagate fibrosarcoma
syngeneic tumors, 5×105 cells from a sarcoma line established
from the
LSL-KrasG12D/wt;p53FL/FLGEMM model (C57BL/6 background) at the 5th passage or
3×105 cells of the established RIF mouse sarcoma cell line
(C3H/HeJ background, RRID:IMSR_JAX:000659) at the 9th passage were
injected subcutaneously or intramuscularly in the right thigh. Cells from the
LSL-KrasG12D/wt;p53FL/FLGEMM model were recently isolated for the purpose of this research. The
established RIF cell line has been maintained in the laboratory of Dr. Busch for
more than 20 years and originated from cells of the same line at Roswell Park
Cancer Institute in Buffalo, NY. Both cell lines were authenticated and tested
mycoplasma negative by IDEXX BioAnalytics (CellCheck 19 plus) in 2021. Tumors
were irradiated upon reaching 100 mm3 in volume. Tumor size was
measured utilizing calipers and volume was calculated as: (Length ×
Width2)/2.