Malignant transformation is a complex multistep process involving numerous genetic changes, which include loss of tumor suppressor gene function, oncogene activation and alteration of modifier genes.

• 恶性转化是复杂的、渐变的过程,涉及许多遗传改变,包括抑癌基因失活、癌基因激活和其他调节基因功能改变。