On the other hand, we have demonstrated that K14Cre; RbloxP/loxP; TP53loxP/loxP mice (pRb-; p53-) and K14Cre; TP53loxP/loxP mice (p53-) develop highly undifferentiated and very aggressive spontaneous squamous cell carcinoma in the skin [30] that display a high lung metastatic capacity (submitted). This evidence concerns the gene TP53 and squamous cell carcinoma.