PTPRC and neoplasm: Regardless of origin, the biological activity of these chemoattractants, the rapid infiltration of CD45-positive leukocytes into lung adenocarcinomas after p53 reactivation, and the subsequent fibroblast recruitment during tumor regression suggests that p53 orchestrates an immune reaction in the lung microenvironment that leads to the surveillance and destruction of cancer cells by the innate immune system followed by a fibrotic healing process.