植物細胞會癌變嗎？植物體內有沒有癌細胞？脫分化與癌變的區別是？
查了百度的相關回答，只有植物瘤，但只是一種植物無性繁殖保護方式，實際是脫分化。有人說植物細胞不會癌變，原因可能與細胞壁有關。問題如題，想了解更清楚一些
惡性腫瘤（癌）與良性腫瘤的重要區別是惡性腫瘤可以轉移。植物細胞的細胞壁結構恰恰阻止了植物細胞向其他部位擴散。因此，植物只會得良性腫瘤，不會得惡性腫瘤（癌）。
另外，植物脫分化是正常的過程。腫瘤是非正常的，因此不是脫分化（當然，可能會伴隨一些脫分化的特徵）。一般情況下，植物的腫瘤是由病毒或細菌引起的。@xiaopeng xiong
http://www.nature.com/nrc/journal/v10/n11/full/nrc2942.htmlA major difference between plants and
animals is that plant cells are surrounded by
an extracellular matrix (ECM) — the cell
wall — that is much more rigid than the ECM
of an animal cell. The interaction between
a precancerous cell and the ECM is important
at several stages in cancer progression,
especially in maintaining cell identity and
preventing metastasis. In plants, the tight
adhesion between cells not only precludes
metastasis but recent evidence also suggests
that the ECM is a key component required to
maintain organized development. Mutations
in TUMOROUS SHOOT DEVELOPMENT
(TSD) genes lead to a progressive loss of cell–
cell adhesion, disorganized growth and perturbation
of the meristem. The corresponding
genes encode cell wall-modifying proteins:
TSD1 is a glucanase thought to be involved
in cellulose (a major component of the cell
wall) synthesis117 or modification, and TSD2
is a putative pectin methyltransferase that
affects cell–cell adhesion118. Recently, RBR
has been shown to have a role in maintaining
cell–cell adhesion in the shoot meristem53,
as conditional knock down leads to separation
between neighbouring cell layers. Genes
encoding ARABInOGAlACTIn proteins,
ECM components that are implicated in cell
adhesion, are rapidly downregulated after
RBR knockdown53, possibly contributing to
the loss of adhesion and the associated loss of
cell layer organization. RBR is clearly crucial
for multicellular organization in plants at several
levels, and the comparison with mammalian
systems is likely to provide information
about the logic of the underlying strategies
used in these two systems.
至少我搜索出的文獻里沒有植物腫瘤轉移的案例報道。
然後一些小的科普文
http://www.nytimes.com/2013/07/16/science/can-plants-get-cancer.html?_r=0http://www.huntington.org/uploadedFiles/Files/PDFs/GIB-DoPlantsGetCancer.pdf最後再說說知乎里另外的那個問題。也是看了你給的鏈接才知道已經有人回答過了。但排名最高的答案里對癌的定義我並不十分認可。What Are Tumors?總體而言，腫瘤分為良性和惡性。癌是惡性腫瘤的別稱。惡性腫瘤不僅需要侵略性，還需要可轉移性。所以，像Fibromatosis這種在原位點滲透性很強的腫瘤，由於缺乏可轉移性，仍被認為是良性腫瘤。那個回答引用了一篇1919年的文獻，稱植物腫瘤分為良性和惡性，劃分依據大概是腫瘤是否對植物有致死性。但這種劃分並不符合現代的定義。（1919年，科學家對腫瘤和癌症的研究尚處於起步階段，因此定義與現在存在偏差也是正常現象）。
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