In addition, co-expression of twist1a+/kras+ in zebrafish that had been exposed to LPS was found to exacerbate metastasis compared with twist1a+/kras+ zebrafish that had not been exposed to LPS, indicating that LPS could activate liver tumor progression and metastasis in kras mutants in vivo by cooperating with the twist1a gene. The gene discussed is KRAS; the disease is Neoplasm of the liver.