What is a characteristic feature of cancer cells compared to normal cells?

Cancer cells often exhibit uncontrolled growth and division, which is a key characteristic distinguishing them from normal cells. One of the critical features is their ability to create their own growth factors. Growth factors are proteins that stimulate cell proliferation and survival; normal cells typically require external signals for growth and division. In contrast, cancer cells can produce these signals themselves or may express growth factor receptors that are always active, leading to continuous proliferation even in the absence of the usual regulatory signals.

This self-sufficiency in growth signal production contributes to the hallmark of cancer known as "sustaining proliferative signaling." It allows cancer to bypass normal cellular controls that regulate the cell cycle, ultimately leading to tumor growth and the potential for metastasis.