What are the fundamental differences between a malignant cell and a benign cell?

The fundamental difference between a malignant cell and a benign cell lies in their behavior. Malignant cells have the ability to invade surrounding tissues, form metastases (spread to distant locations in the body), and evade detection by the immune system. Benign cells, on the other hand, grow slowly and stay localized with no ability to spread or become cancerous.

Malignant cells are often characterized by uncontrolled mitotic division which can lead to an increase of malignant tumor mass. They can also multiply indefinitely; that is, they don't run out of cellular energy unlike benign tumors which stop growing after they reach a certain size due to limited energy supply.

Unlike benign cells, malignant ones have lost their normal contact inhibition capability – meaning that they continue dividing without respect for normal boundaries between each other and can even penetrate into nearby organs or vessel walls before eventually spreading through the bloodstream or lymphatic system if not treated timely. Furthermore, these altered cancerous cells often fail to undergo apoptosis (programmed death) when they should – this causes them to accumulate over time leading to further progression of disease state.

At a molecular level, malignant cells may demonstrate changes in membrane proteins involved in adhesion such as integrins; DNA damage from exposure to carcinogenic agents; genetic mutations; and expression of abnormal growth-regulating proteins like oncogenes/tumor suppressors as well as proto-oncogenes whose levels are profoundly altered compared with those found in benign cancer versions albeit usually involving only one gene instead of multiple genes at once - thus highlighting the complexity behind it all!