Task: Named Entity Recognition
Input (English):  To better understand the relationship between expression of an oncogene and genetic instability , we have studied a cell line expressing an activated human Ha - ras under the control of bacterial lactose operon regulatory elements for changes in methotrexate resistance and dihydrofolate reductase ( dhfr ) gene amplification following mutant Ha - ras induction .
Output (English): dihydrofolate reductase