Final answer:
A single cell transformation within tissue can lead to tumor formation, resulting from genetic alterations. These tumors may be benign or progress to become malignant, potentially causing cancer. The transformation can result in unlimited growth and the creation of immortal cell lines like the HeLa cell line.
Step-by-step explanation:
When a single cell in the tissue undergoes a transformation, it often leads to the development of a mass of cells known as a tumor.
This transformation is the result of accumulated genetic damage to genes that control cell growth and division, such as proto-oncogenes and tumor-suppressor genes. Mutations and epigenetic changes can provoke a normal cell to divide abnormally, potentially leading to the formation of tumors. Some tumors remain benign and do not pose a significant risk to health; they maintain the property of controlled growth. However, others may progress to malignancy, forming cancerous tumors that invade surrounding tissues, promote angiogenesis, and can metastasize to different parts of the body. The altered cells in these malignant tumors may have chromosomal rearrangements, deletions, and a lack of contact inhibition, which can lead to unlimited growth in culture, resembling eternal cell lines such as the HeLa cell line.