Comparison of gene expression in cisplatin resistant tumors to chemonaive tumors from a lung cancer mouse model

Using a mouse model of non-small cell lung cancer driven by activated Kras and loss of p53 (KrasG12D;p53fl/fl), we sought to determine which genes change expression in the bulk tumor after repetitive treatment with cispatin. After tumors were treated multiple times with cisplatin and show no further response, we isolated RNA from tumors treated with cisplatin or a vehicle control (PBS) to determine which genes significantly change in expression in chemoresistant bulk tumors. 5 replicates of two conditions were tested. In one condition, KP mice with tumors were treated with Cisplatin (7mg/kg) once a week for three weeks until tumors were resistant to Cisplatin. Tumors were microdissected and combined for RNA extraction and hybridization to arrays. In the second condition, chemonaive mice were treated with a vehicle control (PBS) and untreated tumors were harvested for RNA extraction and hybridization to arrays. All samples were analyzed relative to a reference control.