Editing Metastasis (section)

==Research==
Although metastasis is widely accepted to be the result of the tumor cells migration, there is a [[hypothesis]] saying that some metastases are the result of inflammatory processes by abnormal immune cells.<ref>{{Cite journal |vauthors=Shahriyari L |date=2016 |title=A new hypothesis: some metastases are the result of inflammatory processes by adapted cells, especially adapted immune cells at sites of inflammation |journal=F1000Research |volume=5 |pages=175 |doi=10.12688/f1000research.8055.1 |pmc=4847566 |pmid=27158448 |doi-access=free}}</ref>  The existence of metastatic cancers in the absence of primary tumors also suggests that metastasis is not always caused by malignant cells that leave primary tumors.<ref>{{Cite journal |vauthors=López-Lázaro M |date=2015-01-01 |title=The migration ability of stem cells can explain the existence of cancer of unknown primary site. Rethinking metastasis |journal=Oncoscience |volume=2 |issue=5 |pages=467–475 |doi=10.18632/oncoscience.159 |pmc=4468332 |pmid=26097879}}</ref>

The research done by Sarna's team proved that heavily pigmented [[melanoma]] cells have [[Young's modulus]] about 4.93, when in non-pigmented ones it was only 0.98.<ref name="Sarna_2019">{{Cite journal |vauthors=Sarna M, Krzykawska-Serda M, Jakubowska M, Zadlo A, Urbanska K |date=June 2019 |title=Melanin presence inhibits melanoma cell spread in mice in a unique mechanical fashion |journal=Scientific Reports |volume=9 |issue=1 |pages=9280 |bibcode=2019NatSR...9.9280S |doi=10.1038/s41598-019-45643-9 |pmc=6594928 |pmid=31243305}}</ref> In another experiment they found that [[Elasticity (physics)|elasticity]] of melanoma cells is important for its metastasis and growth: non-pigmented tumors were bigger than pigmented and it was much easier for them to spread. They showed that there are both pigmented and non-pigmented cells in melanoma [[Neoplasm|tumors]], so that they can both be [[Drug resistance|drug-resistant]] and metastatic.<ref name="Sarna_2019" />