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55

There are different reasons why cancer patients are mostly excluded from donating organs. Although the probability of transmitting cancer is small, it is not zero. Also tumors tend to form metastases over time, which spread throughout the body. It is possible that a cancer has formed metastases in other, distant organs, which are too small to detect. Since ...


42

Laetrile/Amygdalin has been claimed to be a suitable treatment for 'cancer' (which is a summary term for an extremely heterogeneous class of diseases). Even though laetrile/amygdalin in these claims is often called a vitamin, it in fact is not a vitamin as the molecule is not essential for the metabolism (Greenberg (1980)). The claimed effects of laetrile/...


36

Can a cancer cells from someone else's body cause cancer in a healthy person? No. Cancer cells from another person cannot cause cancer in a healthy person. The rare cases of transmissible tumors all involve unhealthy or not yet developed persons. Transmission of tumor cells from one individual to another happens, but is quite rare, and in all cases ...


28

Before OP edited his/her question, it was a little unclear whether the question was only about humans. The following answer is more general than asked as it also considers cancers in non-humans Most cancers are not transmissible but some are. We call them (clonally) transmissible cancers. Transmissible cancers The most famous case of transmissible cancer ...


24

On of the main reasons why cancers are normally not transmissible between different people is basically the same reason as why organ transplants are difficult: histocompatibility. Every human cell carries a set of human leukocyte antigens on its surface, and (except for identical twins) every person's cells carry a different set of antigens. Any cells that ...


21

Short Answer: No. Background: First of all, there is no such thing as vitamin B17. The compound, amygdalin or laetrile, which is referred to by this term, is not a vitamin1. Amygdalin is indeed a cyanogenic glycoside (like glucosinolates, see this answer) which is poisonous to organisms including humans, because it forms cyanide which is toxic2. See this ...


19

A tumour is simply a space-occupying lesion (something that should not be there, that is; a "lump") caused by abnormal cell replication. (In medicine, the word "tumour" literally means "swelling", and can sometimes refer to that instead, but that's a different story). Cancer is a disease in which cell replication is totally out of control. What causes ...


17

Rather than 'breaks' caused by high energy radiation, UV radiation causes chemical modifications of the bases ('letters') that make up DNA. There are four bases in the DNA alphabet abbreviated to A,T,G or C belonging to two classes. A & G are guanines while T & C are pyrimidines. When you have pyrimidine bases next to each other on a DNA strand, they ...


16

Such projections are more formally known as spiculations. Most commonly, we talk about spiculations with respect to the radiographic appearance of malignant breast and lung lesions. This paper* describes the correlation between the mammorgraphic appearance of spiculated breast lesions and their pathology (microscopic appearance), which is a reasonable start ...


15

The HeLa cell line is undoubtedly the most used and investigated human immortal tumor cell line. Extracted from a cervical tumor from Henrietta Lacks in 1951 at Johns Hopkins hospital, Baltimore, MD these cells proved immortal and are still used in many, many labs worldwide today. It is the oldest human cell line in use and, therefore, the oldest human ...


15

There are very many photochemical reactions: Up to 50–100 mutagenic reactions on DNA per second might occur in a skin cell during exposure to sunlight, but are usually corrected within seconds by photolyase reactivation or nucleotide excision repair. (That's just DNA, excluding O2 and other cell constituents) chemist ref and wiki ref Molecules that absorb ...


14

The methodology behind homeopathy is scientific nonsense. If you dilute anything a billion times, it will have no chemical effect, not even if you shake it all the while. So no, homeopathy does nothing for cancer, or any medical condition at all. Of course plants can have active compounds in them, once scientists have identified those compounds, they can ...


14

Short version: This is nonsense, cancer does not arise from nutritional deficiencies. Long version: The substance is called Amygdalin, a poisonous cyanogenic glycoside. It can be found in higher concentration in the kernels of several plants including apricots, plums, bitter almonds, peach, plum. The semisynthetic, modified form is called Laetrile. Taking ...


13

Interesting question. I believe it definitely is an evolutionary process. unicellularity breaking away from a multicellular life. There are two examples that I can think of, which can support this argument: Hela cells: Hela cells have been classified as a different organism because they have the ability to grow outside the host indefinitely and their ...


13

Short answer All mutagens are potential carcinogens unless the mutagen is highly specific to a site. As noted in the question, carcinogens need not be mutagenic. HPV causes oncogenic transformation of a cell because of certain proteins that it expresses. HPV is considered a carcinogen by the IARC. Some retroviruses are oncogenic: they might carry an ...


13

How can a non-mutagenic agent be carcinogenic? An agent that causes overexpression of oncogenes or inhibition of tumor suppressors, would be carcinogenic but not mutagenic. HPV, for instance, produces proteins that cause inactivation and degradation of tumor suppressors, p53 and pRb[1]. Regarding alcohol. As you guessed, alcohol is metabolized to form ...


12

This is a great question. Just to make it clear people with DS do have a reduced risk of solid cancers and an increased risk of blood cancers, (B-ALL and AML). You are correct in picking out DSRC1 because of its angiogenic implications. The current hypothesis centers around people with DS being less capable of driving angiogenesis, and therefore having an ...


12

Short answer Large animals do get cancer. They may contract cancer with an incidence less than that estimated by absolute cell numbers, but there seems to be a lack of data on cancer rates in large animals to support this hypothesis conclusively. Background Whales contract cancer (Martineau et al, 2002). There does, however, seem to be a lack of correlation ...


12

Alcohol itself is non-mutagenic because it does not directly alter DNA. (Additionally ethanol enhances carcinogenesis and is itself not a carcinogen - updated) There are similar non-mutagenic carcinogens such as estrogen - which is a carcinogen. Another important thing to realize is that a non-mutagenic carcinogen may not alter DNA, but instead alter ...


10

This is a specific version of the great cancer question: "Why are some cancers more common than others?" The answer is either "Some have more common causes", and (or) "Some are cured spontaneously more often". So now all you are asking is "What causes cancer?" and "How do we cure it?" Given that, I don't expect a general definitive answer will be ...


10

The cells never died in the sense that they kept replicating, individual cells still died. They were safely cultured in petri dishes before Henrietta Lacks died. The cells came from a tumor that developed from her cervix. The cervical cancer cells had developed high telomerase activity. Telomerase builds telomeres on the ends of DNA, protecting the ...


9

Cancer cells and normal cells differ on the genetic basis but they share the same genetic background, so they have not different DNA in the sense of two different people. They have to be different, since cancer cells have to accumulate mutations on a number of genes to become a cancer cell, which can survive and will not be directed into apoptosis. These are ...


9

Interesting question. My answer is no, but it requires a rather science-fiction style answer - at least it's beyond current technology, but here goes: My Assumptions I make the simplifying assumption that ageing is only related to telomere length. Thus by "avoid ageing" I assume you mean "avoid telomere shortening". Also to clarify things for others, I'll ...


9

Cigarette smokers are most certainly prone to cancer. See Cecil Medicine, Chapter 183, on the epidemiology of cancer, exposure to tobacco is the most important environmental risk factor for cancer development, at least in the US: Exposure to tobacco is the single largest cause of cancer in the United States... All forms of tobacco can cause cancer. ...


8

Ewing's sarcoma is a bone cancer. As such, it does not arise as a primary tumor in the heart. Ewing's sarcoma does metastasize. Like any metastatic cancer, it seeds along it's venous return to the heart, "taking root" in suitable tissue. Cardiac metastases of Ewing's sarcoma are exceedingly rare, with only a few reported cases. Since all blood returns to ...


8

Good question. There are many organisms that are technically biologically immortal. However, I would like to point out that the definition of biological immortality is this: ...cells that are not limited by the Hayflick limit, where cells no longer divide because of DNA damage or shortened telomeres. (That's from here.) So biological immortality ...


7

There's a 2003 paper published in the Journal of Korean Medical Science describing a case of a 'homunculus' within a teratoma: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3055135/ It contained some hair, brain tissues, cranial and other bones, but no internal organs.


7

Sharks sense their prey with the normal senses, they see, hear and smell them. They have a remarkable sensitive sense of smelling, which enables them to sense highly diluted traces of prey. They can also use their smelling to determine the direction where a certain smell comes from. This is achieved by the timing in which the senses arrive in different ...


7

Cancer cells can be and are used in cell culture. HeLa cells were the first human cell line to be grown in culture and they were derived from a cervical tumor. That being said, Cancer cell lines would not necessarily be used for stem cell work. They have sustained too many mutations to study the type of questions that stem cells are used to study, though as ...


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