▁but ▁in hib its ▁migration ▁of ▁normal ▁o var ian ▁surface ▁ep ith el ial ▁cells . ▁Most ▁( more ▁than ▁ 9 0 %) ▁o var ian ▁can cers ▁arise ▁from ▁the ▁ep ith el ium ▁of ▁the ▁ov ary . ▁Therefore , ▁ext rac ell ular ▁S 1 P ▁could ▁have ▁an ▁important ▁role ▁in ▁cancer ▁pro gression ▁by ▁prom oting ▁migration ▁of ▁ep ith el ial ▁o var ian ▁cancer ▁cells . ▁ ▁O zon ization ▁of ▁human ▁blood ▁is ▁associated ▁with ▁increased ▁concentr ations ▁of ▁S 1 P ▁in ▁the ▁pl asma . ▁ ▁In ▁addition , ▁ ▁S 1 P ▁mod ul ates ▁the ▁pro l ifer ation ▁of ▁skin ▁cells . ▁This ▁in ▁particular ▁applies ▁to ▁ker atin ocy tes ▁while ▁fib ro bl asts ▁are ▁not ▁addressed ▁in ▁this ▁way , ▁apart ▁from ▁cell ▁growth ▁and ▁different iation ▁ ▁While ▁S 1 P ▁suppress es ▁e pid erm al ▁pro l ifer ation ▁as ▁the ▁gl uc oc ort ico ids ▁do , ▁it ▁diff ers ▁from ▁them ▁in ▁so ▁far , ▁as ▁pro l ifer ation ▁of ▁der mal ▁fib ro bl asts ▁is ▁not ▁reduced . ▁In ▁fact , ▁S 1 P ▁even ▁activ ates ▁fib ro blast - der ived ▁ext rac ell ular ▁matrix ▁protein ▁production . ▁ ▁As ▁a ▁drug ▁Administration ▁of ▁S 1 P ▁has ▁been ▁shown ▁to ▁protect ▁o ocy tes ▁from ▁chem other ape ut ic ▁agents ▁in ▁vit ro , ▁as ▁well ▁as ▁in ▁v ivo ▁from