Discussion of all aspects of cellular structure, physiology and communication.
Well, I'm not sure about meiosis, but during the G1 phase of the cell cycle, cells pass through a checkpoint and the signals that the cell receives from its surrounding environment will cause a healthy, normal cell to either enter the G0 phase or into normal mitosis. Mutated cells often have a defect in the GI checkpoint, and rather than going into either G0 or mitosis, they enter a state of wild, unequal division, leading to cancer.
There are 10 types of people in this world. Those who understand binary, and those who don't.
I am nearly sure that meiosis do not cause cancer. the cells produced in meiosis are not a permanent part of the body. I mean they are used or given out of the body. It would be nonsense to become cancerous. there would be no metastasis available.
Cancer is defined as "uncontrolled cell division." Someone correct me if I am wrong, but I am almost positive that once a cell undergoes meosis, it lacks the nuclear components to be able to divide again even if it wanted to.
During meiosis there is a crossing over process.
I think during this process, there is no defined program that what genes or what segments to be recombined.
One thing i have read is that there is one gene that triggers apoptosis process when the time is come for one cell.
Another is that, there is proof-reading gene (p53) during gene expression.
What if these genes are damaged during meiosis?
But the probability of occuring so may be very small.
But it is possible isn't it?
So, it may sometimes (sometimes) lead to cancer, i think.
This is only my opinion.
I really apologize from you. I found some info about these kind of tumors. they are called GERM CELL TUMORS. hope this is what you want.
here is the link:
http://web1.tch.harvard.edu/cfapps/A2Zt ... l%20Tumors
With the exception of crossing over, the first half of meosis is identical to mitosis. For cancer to work, cells must completely go through cell division. If these germ cells only undergo half of meosis, then the chromosomes will duplicate as well.
While it might be said that these cells are repeating the first half of meosis over and over again, but I say that they are going through a corrupted form of mitosis...and we all know that cancer is another corrupted form of mitosis.
Show me more evidence and I will accept your hypothesis.
I will try to find some more and send it. here is the one I just found. there is a sentence like this: (pay attention):
"Although cancer is a very complex disease, it has recently become clear that many of our very own genes that are supposed to be working in our cells to control cell division (mitosis and meiosis) are responsible for the cancer epidemic."
here is the link:
And another one:
"It is significant, however, that chorionepithelioma is not always confined to the reproductive organs nor is it found only in the female. Testicular chorionepithelioma as well as primary extra-genital chorionepitheliomas in both sexes present cytotrophoblast that is indistinguishable from that of the normal pregnancy trophoblast. It is generally accepted that testicular chorionepithelioma arise from germ-cells (diploid totipotent cells2), but the fact is usually overlooked that such cells must first undergo meiosis to produce the trophoblast-competent gametogenous cell that has, as the only alternative to death, the initiation (by division) of a genetically unique life-cycle through the initial production of trophoblast. It is thus of the utmost theoretical importance that the trophoblast cell has never been found outside the canalization of normal pregnancy except as one of the most malignant exhibitions of cancer. And unlike all other cells of the life-cycle, the trophoblast cell is the only cell that has never been found ectopically except as cancer. "
and the link:
"As early as 1879 Arnold observed gametoid (meiotic) mitosis in malignant tissue. About twenty years later Farmer, Moore and Walker reported the occurrence of meiosis (heterotypic mitosis) at the border of malignant tumors. In 1929 Evans and Swezy described in inflamed somatic tissue changes "strikingly similar to those of meiotic mitosis." In 1936 Hearne observed meiotic changes in tissues cultured with methylcholanthrene and Molendorff made similar observations in 1939 with estrone."
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