Final answer:
Cancer cells exhibit a loss of contact inhibition, allowing them to continue dividing despite having no additional space, leading to tumorous growth and potential metastasis due to a lack of proper cell communication and junction formation.
Step-by-step explanation:
Cancer cells exhibit loss of contact inhibition, which means when there is no more room, the cells still continue to divide. This loss of control over the cell cycle results in the cells rapidly dividing without the ability to stop, even when they come into contact with other cells. In normal cells, contact inhibition signals cells to stop dividing when they form a complete single layer, as in tissue formation. However, cancer cells lack the necessary gap junctions, integrins, and cadherins, failing to communicate and form proper junctions, and thus continue to divide uncontrollably, leading to tumorous growth and potential metastasis.