Final answer:
Tumor-suppressor proteins, such as RB1, p53, and p21, are encoded by tumor suppressor genes and can prevent uncontrolled cell division, reducing the risk of cancer. They differ from oncogenes, which promote cell division and cancer. Cancer research often focuses on these proteins to develop targeted therapies.
Step-by-step explanation:
Tumor-suppressor proteins are the type of proteins that can suppress cancer. These proteins are encoded by tumor suppressor genes, which function as crucial regulators of cell division. When activated, they can prevent cells from undergoing uncontrolled division, acting as a roadblock to cell cycle progression. The best-understood tumor suppressor proteins include retinoblastoma protein (RB1), p53, and p21. These proteins are essential for ensuring that cell division does not occur when there are errors in the DNA or other forms of cellular stress.
It is important to note that these tumor suppressor proteins are different from oncogenes, which when mutated, can lead to increased cell division and cancer. Moreover, genetic mutations, such as those induced by human papillomavirus (HPV), can affect p53 activity, leading to an increased risk of cervical cancer. Thus, targeting the function of tumor suppressor proteins is a crucial aspect of cancer research and therapy.