Experimental Study On Promoter Methylation Of Survivin Gene In Infancy Hemangioma

Objective: To investigate the promoter methylation status of survivingene in different periods of hemangioma and normal skin tissues by usingbisulfite sequencing PCR (BSP).The role of survivin genetic methylationin proliferative and involuting hemangiomas also will be discussed.Methods:(1)The expression of survivin were examined by S-Pimmunohistochemistry in paraffin-embedded tissues from30cases ofproliferative hemangiomas,30cases of involuting hemangiomas,10casesof normal foreskin.(2)Genomic DNA were extracted and purificated inparaffin-embedded tissues from different samples,bisulfite sequencingPCR (BSP) technique were used to analyze the methylation status of theCpG island in the survivin gene promoter region in30cases ofproliferative hemangiomas,30cases of involuting hemangiomas and10cases of normal foreskin.Results:(1)The positive expression rate of survivin protein inproliferative hemangiomas,involuting hemangiomas and normal foreskintissues was76.6%(23/30),33.3%(10/30) and20%(2/10).The survivinprotein expression was significantly greater in proliferative hemangiomasthan in involuting hemangiomas(x~2=7.16， P<0.05).there was not astatistical difference between involuting hemangiomas and normal foreskin tissues(x~2=3.98，P>0.05);(2)The methylation status of the CpGisland in the survivin gene promoter region has a significantlydifference between proliferative hemangiomas, involuting hemangiomasand normal foreskin tissues. In10cases of normal foreskin tissues,onlyone cases(10%) was demethylated,9cases(90%) was methylated;in30cases of involuting hemangiomas,8cases(26.6%) was demethylated,22cases(73.3%) was methylated;in30cases of proliferative hemangiomas,24cases(80.0%) was demethylated,6cases(20%) was methylated; thesurvivin gene promoter region in80%proliferative hemangiomas wasdemethylated,the demethylated rate was significantly lower inproliferative hemangiomas than in involuting hemangiomas(x~2=11.53，P<0.05);the survivin gene promoter region in normal foreskin tissues wasalmost methylated.(3) The CpG island in the survivin gene promoterregion was unmethylated in31cases of the33hemangiomas expressedsurvivin protein, the CpG island in the survivin gene promoter region wasmethylated in26cases of the27hemangiomas unexpressed survivinprotein.There was a closely relationship between the methylation status ofsurvivin and the protein expression of survivin.The demethylation ofthe promoter CpG island was positively correlated with the survivinprotein expression(r=0.915,2=9.84,P<0.05),and the methylation wasnegatively correlated with the survivin protein expression(r=-0.879,x~2=9.27,P<0.05).Conclutions:(1) The survivin protein expression was significantly greater in proliferative hemangiomas than in voluting hemangiomas;(2)The methylation status of the CpG island in the survivin gene promoterregion has a significantly difference between proliferative hemangiomas,involuting hemangiomas and normal foreskin tissues;(3) The methylationstatus of survivin gene promoter was correlated with the survivin proteinexpression in hemangiomas;(4) Aberrant methylation of the CpG island inthe survivin gene promoter region maybe play a role in the proliferationand involution of hemangiomas.