The following is not a feature of malignant transformation by cultured cells-

Malignant transformation is the process by which cells acquire the propeies of cancer. This may occur as a primary process in normal tissue, or secondarily as malignant degeneration of a previously existing benign tumor. Causes of malignant transformation There are many causes of primary malignant transformation, or tumorigenesis. Most human cancers in the United States are caused by external factors, and these factors are largely avoidable.