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Since cancer cell retain their ability to trigger the immune system from their pre-cancerous state and any condition that causes an auto-immune reaction in a specific area of the body will attack any cells in that area then could an auto-immune reaction actually attack any cancer cells in that area also?

Noting that regular human cells are not able to avoid 'attacks' by an auto-immune response so the normal cells can not pass on any 'strategies' for avoiding an auto-immune disease attack to any cancerous cells they 'turn into'.. Is all this possible?

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There are several types of cancer immune evasion. Such as releasing immunesupressive cytokines, downregulation of MCH and comprising mutiations which are not immunogenic. If the cancer at a tissue is evading immune system by immunosupressive cytokines it may not be affected from auto-immune attack. However if the cancer is not attacked by the immune system just because it is not "different" enough from the nearby healthy tissues, then at this time auto-immune attack to the tissue may technnically attack the cancer also.

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  • $\begingroup$ Has there been instances where an auto-immune reaction has attacked tumour cells? $\endgroup$ – 201044 Jan 11 '16 at 3:15
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    $\begingroup$ I haven't read about such case. But it is more like "Has there been a car accident which treated cancer by removing the cancerous tissue (skin) "? Even if there is not known case, it does not make such "treatment" impossible. If normal immune system doesn't attack cancer just because it recognize cancer as "self" then when auto-immune disorder starts it will attack to "self" so to the cancer which is same as that "self". However if immune system already recognized and poised to attack the, but inhibited by inhibitory receptors and ligands, then autoimmune may fail to attack the cancer $\endgroup$ – TeoFriendly Jan 11 '16 at 14:03
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    $\begingroup$ PS: could not edit the previous comment for grammar correction. the last sentence should be "However if immune system already recognized and poised to attack the cancer, but inhibited by inhibitory receptors and ligands, then autoimmune may fail to attack the cancer" $\endgroup$ – TeoFriendly Jan 11 '16 at 17:43
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Mostly wrong, yet not a bad notion.

Most* (*all? Been too long.) forms of cancers turn off the natural identification scheme (self-MHC or major histocompatibility complex) as well as the limits on replication. This is because there is a self-kill switch attached to that system.

A cancer would need to release the stand-down signal in a timely fashion, which it cannot do if it is spending its resources on rapid growth.

This means most* cancers are already valid targets without needing an auto immune disorder.

At least one targeted anti-cancer treatment operates by turning MHC back on, causing them to die.

There may be some sorts where the ability to target native cells would help. Doubt it, but could be.

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  • $\begingroup$ Could a benign virus cause an auto-immune reaction in a persons right knee say and therefore cause all the cells in the knee to be attacked by the immune system including any cancer cell that are there ( even though they can avoid the 'regular' immune system attack?? $\endgroup$ – 201044 Jan 11 '16 at 2:50
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    $\begingroup$ Histamine triggers all sorts of nasty cell reactions. It is quite destructive, so it's fairly localized. It does real harm. A parasite would work by triggering that reaction and, potentially, by eating the cancer cells. Whether or or not that damage is recoverable is contingent on extent, much as with surgery. $\endgroup$ – The Nate Jan 11 '16 at 3:19
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    $\begingroup$ Auto immune reactions are often genetic, but that doesn't always mean heritable. Some forms can be triggered by expression errors like in MHC. There are chemical agents that can wreck the body's ability to trigger an immune response. Not totally sure how selective immunity restores itself, but there is some form of coordination between cells and immune system when the self MHC codes are set, so there is likely something that can hack that and change what's read. (This is a really involved topic, though, and better asked over on biology, methinks.) $\endgroup$ – The Nate Jan 11 '16 at 10:41
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    $\begingroup$ Theoretically, since transcription errors can naturally cause this, it should be possible via some form of DNA manipulating enzymes. (a retrovirus, say.) I assume it's possible other ways, too. $\endgroup$ – The Nate Jan 14 '16 at 8:14
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    $\begingroup$ Yes, that's theoretically possible. It would need to encode the changes directly or indirectly. (The enzymes to alter that gene expression region or the control signals to create those enzymes or force a situation that otherwise causes this.) I've no idea if that's a phenomenon actually found in nature. $\endgroup$ – The Nate Jan 14 '16 at 8:32

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