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A critical event in the later stages of carcinogenesis is the reactivation of the enzyme telomerase. Telomerase is usually only active during development when it sets up a normal length of telomeres in all of our cells before and immediately after we are born. Cancer cells, however, use telomerases to avoid death by telomere shortening. When cancer cells evade tumour suppression, it continues dividing and suffer telomere shortening until it reaches a state called 'crisis' when normal cells would automatically die. Cancer cells, however, can endure crisis at the cost of losing its telomeres. When telomeres are lost, repair mechanisms attach chromosomes to each other to avoid further shortening of the chromosomes. However, this highly anomalous event only causes the chromosomes to rip apart at random locations during the next replication cycle and induce genomic instability. This result of the instability is the random relocalization of fradments of chromosomes and eventually this can lead to the death of the cell or the reactivation of telomerase due to a random mutation (such as one that puts the telomerase gene under the promotion of a highly transcribed gene). This model has been scientifically verified since most malignant cancers are telomerase positive and interestingly, some laboratories that immortalize human cells for study also had to reactivate telomerase in these cells through a process of induced crisis.
What else can I help you with?
Is the percentage of cells in the resting stage is higher in cancerous cells than normal cells?
No, cancer cells are more active than normal cells. Cancer cells are always dividing at a faster rate than normal cells.
What does the presence of telomere caps give cancer cells?
Immortality. "A hallmark of cancer cells is immortality. The only cells in the body that are usually 'immortal' are germ cells and some stem cells. Other cells in the body are not immortal and can divide only a limited number of times before they either cease dividing or die. One block to unlimited cell division is a specialized structure at the end of each chromosome called the telomer." (Huether, McCance 2008, p 231)
Does the cell cycle become uncontrolled in cancer?
Yes
How is the behaviour of cancer cells different from that normal cells?
Cancer cells have the ability to grow and divide uncontrollably, whereas normal cells grow and divide in a regulated manner. Cancer cells can also invade surrounding tissues and spread to other parts of the body, a process known as metastasis, which normal cells do not do. Additionally, cancer cells may evade the body's immune system and resist cell death signals that would normally eliminate damaged cells.
What is the difference between cancer cells and normal cells?
Cancer cells normally have a defect in their receptor proteins on the membrane. There are several growth receptors on the surface of cells, and if one of them is faulty, cancer may form. The cancerous mass will continue to divide if there is no negative feedback from the cells surrounding it. In addtition to not being able to receive normal signals that regulate the cell cycle, cancer cells do not stop dividing when growth factors are depleted, simply put cancer cells don't require nutrients to grow, however they may still receive nutrients. As long as a cancer cell is provided with nutrients they may grow indefinately until some random point in the cycle where they may stop, rather then stopping at checkpoints in the normal cell cycle, making them somewhat "immortal". These are the most common differences in cancer cells and normal cells.
Can you get cancer if you get hit but your going through puberty?
No, this doesnt cause cancer. Cancers are caused by mutations of the normal cells, there is no mutation in puberty.
Do all cell types divide limitless times?
No, because of the telomere shortening cells have a limited number of divisions. The exception is with cancer cells that divide indefinitely.
What does bladder cancer do to the normal cells?
Bladder cancer will force normal cells to divide uncontrollably.
What is the link between telomeres and aging?
Telomeres shorten with each cellular replication; telomere length is inversely proportional to age. While telomere extension does tend to make cells "young again", telomere extension is problematic for a treatment for age because many kinds of cancer replicate indefinitely due in part to the fact they have overactive telomerase, a protein that extends the telomeres. Until the link between cancer and telomeres is understood, telomere extension therapy will not be feasible.
Do cancer cells divide at a faster rate than normal cells?
Yes, cancer cells typically divide at a faster rate than normal cells.
What does cells and mitosis has to do with cancer?
it doesnt re-tard
What are the differences between normal cells and cancer cells in terms of their characteristics and behavior?
Normal cells and cancer cells differ in several ways. Normal cells have a controlled growth and division rate, while cancer cells grow uncontrollably. Normal cells have a specific function in the body, while cancer cells lose their specialized function. Additionally, normal cells undergo programmed cell death when necessary, but cancer cells evade this process. Finally, normal cells have a limited ability to spread to other parts of the body, while cancer cells can invade nearby tissues and metastasize to distant organs.
Is the percentage of cells in the resting stage is higher in cancerous cells than normal cells?
No, cancer cells are more active than normal cells. Cancer cells are always dividing at a faster rate than normal cells.
What does the presence of telomere caps give cancer cells?
Immortality. "A hallmark of cancer cells is immortality. The only cells in the body that are usually 'immortal' are germ cells and some stem cells. Other cells in the body are not immortal and can divide only a limited number of times before they either cease dividing or die. One block to unlimited cell division is a specialized structure at the end of each chromosome called the telomer." (Huether, McCance 2008, p 231)
Explain telomere erosion and the role of telomerase?
Telomere erosion is the shortening of the protective caps at the end of chromosomes called telomeres, which occurs with each cell division and is associated with aging and cell senescence. Telomerase is an enzyme that helps to maintain telomere length by adding repetitive DNA sequences to the ends of chromosomes. It is particularly active in stem cells and cancer cells, allowing them to continue dividing without undergoing senescence or apoptosis.
What is the medical definition of telomere?
A telomere in medical terminology means the end of a chromosome that is used to regenerate cells. Every time a cell dies the telomere regenerates the cell.
Do cancer cells have a long or short interphase?
In the cell cycle of cancer cells interphase is still the longest phase. However, interphase is shorter in cancer cells than in normal cells.
