etic ▁alter ations ▁and ▁mut ations ▁affect ▁the ▁cell ular ▁mach in ery ▁that ▁may ▁cause ▁the ▁cell ▁to ▁rep licate ▁at ▁a ▁higher ▁rate ▁or ▁result ▁in ▁the ▁cell ▁avoid ing ▁apo pt osis , ▁and ▁thus ▁contribute ▁to ▁li ver ▁disease . ▁ ▁By ▁the ▁time ▁accum ulating ▁ep igen etic ▁and ▁mut ational ▁changes ▁eventually ▁cause ▁he pat oc ell ular ▁car cin oma , ▁ep igen etic ▁alter ations ▁appear ▁to ▁have ▁an ▁even ▁larger ▁role ▁in ▁car cin ogen esis ▁than ▁mut ations . ▁ ▁Only ▁one ▁gene , ▁T P 5 3 , ▁is ▁mut ated ▁in ▁more ▁than ▁ 2 0 % ▁of ▁li ver ▁can cers ▁while ▁ 4 1 ▁gen es ▁each ▁have ▁hyper m eth yl ated ▁prom ot ers ▁( re press ing ▁gene ▁expression ) ▁in ▁more ▁than ▁ 2 0 % ▁of ▁li ver ▁can cers . ▁ ▁Al co hol ▁consumption ▁in ▁excess ▁causes ▁a ▁build - up ▁of ▁ac etal de hy de . ▁ ▁Ac etal de hy de ▁and ▁free ▁radical s ▁generated ▁by ▁met abol izing ▁alco hol ▁indu ce ▁DNA ▁damage ▁and ▁ox id ative ▁stress . ▁ ▁In ▁addition , ▁activation ▁of ▁neut roph ils ▁in ▁alco hol ic ▁li ver ▁disease ▁cont ributes ▁to ▁the ▁path ogen esis ▁of ▁he pat oc ell ular ▁damage ▁by ▁re le asing ▁re active ▁o xygen ▁species ▁( which ▁can ▁damage ▁DNA ). ▁ ▁The ▁level ▁of ▁ox id ative ▁stress ▁and ▁ac etal de