Why does cancer cell division continue unchecked even with significant DNA damage and absent growth factor signaling?

💡 Explanation

Cancer cells bypass normal growth factor and DNA damage checkpoints because mutations in checkpoint proteins, like p53, disable the cell cycle arrest mechanisms. Therefore, damaged DNA is not repaired, rather than apoptosis occurring, because the cell proceeds through division without regulation.

• Why does drug tolerance increase rapidly within the nucleus accumbens during addiction?
• Why does plaque buildup in arterial vessels increase the risk of hypertension more than a similar buildup in venous vessels?
• A woman with endometriosis experiences increased pain during menstruation. Which mechanism explains why this phenomenon occurs in the reproductive system?
• If a patient with retinitis pigmentosa experiences increasing peripheral vision loss, what explains why gene therapy targeting photoreceptor survival might fail to fully restore vision?
• As aging progresses, why does bone fracture risk increase disproportionately compared to the overall decline in bone mineral density when subjected to impacts?
• What causes increased susceptibility to infections when vitamin A deficiency impairs mucociliary clearance in the respiratory tract?