CCND1 and bone neoplasm: Western blot analysis further revealed that bone tumors of H2‐c‐fosLTR/ColAREG mice displayed elevated activation of the EGFR downstream proteins pRSK2, pCREB and c‐Fos resulting in elevated proliferation with increased cyclin D1 protein expression (Fig 5F) and decreased apoptosis as shown by reduced cleaved caspase‐3 levels (Fig 5G).